fdex810e

PREFACE

This manual is valid for SOPHO Call@Net (previously known as SSW 810), running on all ISPBX models of the SOPHO iS3000 Series. All of these systems will further be referred to as "ISPBX".

LICENSING AGREEMENT

The licensing agreement for an ISPBX determines which facilities are available. It is therefore possible that a facility described here will not work on a specific ISPBX, even though it has been correctly configured. Check the relevant license agreement to determine what is available.

GENERAL NOTE

Fully Integrated Networks (FINs) are only supported by the iS3070/3090!

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1. INTRODUCTION

The primary function of ISPBX is to provide facilities to make voice communication between telephone sets possible. In most cases these telephone sets are normal analogue sets where the speech signal is transformed into an analogue electrical signal and transferred over a 2 wire twisted pair to the ISPBX, where it is converted into a 64 kbps digital signal. This signal is switched in digital form to the required destination. The digital signal is then converted back to analogue form and sent to the destination telephone set. Here the analogue electrical signal is translated back into an audible signal.

The ISPBX can be connected to other PBXs or to the public switched telephone network with analogue trunk or tie lines. A speech connection between telephone sets in different PBXs (or PSTN) uses these trunk or tie lines.

A connection can be made using the ISPBX, from one digital set to another. The same sort of telephone exchange facilities are then offered for digital connections. Various kinds of peripherals can be connected.

It is not necessary to install a dedicated data network on a plant for the transfer of digital information. The digital peripherals can be connected to the ISPBX using the existing telephone wiring. Alternatively, digital connections can be used.

1.1. DATA COMMUNICATION

For the transfer of digital information between two digital parties, terminals or peripherals, the same facilities are available as for voice communication. The ISPBX provides a transparent path between two ports and the terminals determine what kind of information is transferred between the terminals and if necessary what type of protocol is used between them.

1.1.1. Data Communication within the ISPBX

A digital connection can be established using analogue lines by using modems. A modem is connected to an Analogue Line Circuit (ALC) instead of a normal analogue telephone set. The connection between two data parties is established as if it was a normal speech call. The ISPBX is not aware that a digital connection has been made.

A purely digital connection is made by connecting the digital peripheral to a Data Terminal Adaptor which is in turn connected to a Digital Line Circuit (DLC) or a Digital Trunk and Extension (DTX). A Data Terminal Adaptor is a SOPHO-SET, SOPHO-LAM or LAM. Each digital peripheral is connected to a port identified by a directory number (DNR). Peripherals can make contact with each other by dialling the required DNR and if the devices are

compatible (regarding the communication protocol) a connection between the devices can be established. The connection is circuit switched, a continuously established connection between two data parties.

Without the modem higher communication speeds between two internal data parties can be obtained as the modem is often the limiting factor in data communication.

In larger systems, different ISPBX units are connected using 2 Mbps digital inter-unit links and the network acts as if it is one large PBX. The users are not aware of the separate units in the system. This applies both for voice and for data communication.

The terminals in the fully integrated network of these units can be located within one physical location. In this case all units are located on the same premises (interconnected via short 2 Mbps inter-unit lines). Such a network of terminals can be called a Local Area Network (LAN).

It is also possible that the units are located further apart (interconnected via leased 2 Mbps lines through the PSTN for instance) and that the terminals are spread over the entire ISPBX network. In such a case the network of terminals can be called a Wide Area Network (WAN).

1.1.2. Data Communication over an Analogue Route

A modem connection can be established over an analogue trunk or tie line to a data party located in another PBX or in the PSTN. The analogue trunk or tie line is connected to an Analogue Trunk Unit (ATU).

If the data party is connected via a modem to an ALC, then a data call to an ATU can be established as if it was a normal voice call. An outgoing call is made by dialling the trunk access code to the required destination and if necessary the external number of the data party. The dialled digits are transferred over the line in the form indicated by the bundle properties. An incoming call can be directly connected to the ALC after analysing the incoming number.

Operator assistance can be useful for setting up the call, since this type of data call is established using a speech connection. After the connection between the two parties is established the modems are inserted at both sides and the data transfer can take place.

If a data party is connected to a DLC, then conversion is required to enable data to be transferred over the analogue trunk line. A modem must therefore be inserted between the DLC and the analogue trunk line. This is accomplished using a Modem Line Unit (MLU) or a SOPHO-LAM P375.

If a trunk or tie line is dedicated for data calls then a modem can be permanently connected to the line.

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If the trunk or tie line is to be used for both voice and data then another procedure must be followed. Modems are grouped into a pool and are switched into a connection when required, i.e. when a data call is in progress.

1.1.3. Data Communication over a Digital Route

A data connection can be established over a digital trunk or tie line to a data party located in another PBX or in the PSTN. The digital trunk or tie line is connected to a Digital Trunk Unit (DTU).

If the data party is connected via a modem to an ALC, then the external party must also have a modem connection. The modem's modulated carrier signal is digitised by the ALC and are transferred over the digital route as `voice' samples. Incoming and outgoing data calls can be allowed without further requirements.

If a data party is connected to a DLC, then an outgoing data call is established by dialling the trunk or network access code of a digital route. The connection between the DLC and the DTU is made directly. An incoming call can be directly connected to the DLC after analysing the incoming number.

In this way a fully digital connection between the calling data party and the destination data party in different networks is possible.

If the external data party in the opposite network is connected via an analogue line to the external network, a modem must still be used. By means of compatibility check modem pool dialling is possible as described in the part above.

1.2. TEXT COMMUNICATION

The ISPBX offers a transparent path through a network (once a path has been established between two ports, the data that is transferred between the ports is not processed). Text can therefore be transferred as analogue or digital signals.

1.3. IMAGE COMMUNICATION

The ISPBX offers a transparent path through a network (once a path has been established between two ports, the data that is transferred between the ports is not processed). Images can therefore be transferred as analogue or digital signals.

1.4. BOUNDARIES, OPTIONS, TIMERS

For some facilities, certain boundaries, options or timers are important. These parameters are

mentioned in the concerning subjects in this manual together with an indication if it is network (NE) or local (LO) data. More information about these parameters can be found in the Second Line Maintenance Manual.

The boundaries are assigned a value during the projecting of the unit via the PEuu.POM file. When the value of a boundary, timer or option must be changed, this can be effected via a new projecting with an adapted PEuu.POM file.

Most of the options and timers can be changed in an operational system using the second line maintenance command EXSUBC sometimes activated by a hot-start. Boundaries can almost never be changed in an operational system because a change in a boundary results in a new partition of the CPU memory.

For more information: see Facility Implementation Manual; Networking and Routing.

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2. DATA COMMUNICATION WITHIN THE ISPBX

The ISPBX acts as a data network `infrastructure' for the interconnection of end user terminals, peripherals and host computers. Transparent analogue or digital connections are established between digital peripherals in much the same way as a voice connection is established between two telephone sets. The end user terminals may use any protocol for information transfer, provided the path has the capacity for the transmission.

Since the connection between two ports is established for the duration of the data call, this network acts as a Circuit Switched Data Network (CSDN).

A data connection is established, in general terms, as follows:

- The calling party dials the DNR of the required destination. Dialling can be either from the DTE keyboard, from the SOPHO-SET, SOPHO-LAM or LAM, automatically under control of a software program or from a telephone set if a modem is used.

- The ISPBX uses the dialled information to determine the destination, using number analysis. A facility such as `hot line' may also be used to determine the destination.

- The ISPBX checks if the connection is allowed. This involves checking traffic class of the caller, the IBSC of the caller and the BSPT of the destination and the compatibility value connection allowance.

- The called party is rung.- The called party answers. Answering can be either from the DTE keyboard, from the

SOPHO-SET, SOPHO-LAM or LAM, automatically under control of a software program or from a telephone set if a modem is used.

- If the two DTEs are compatible then data transfer can take place.- After data transfer (or even during data transfer), either party may break the connection.

This can be either from the DTE keyboard, from the SOPHO-SET, SOPHO-LAM or LAM, automatically under control of a software program or from a telephone set if a modem is used.

If the two DTEs are not located in the same unit, then the data is transferred between the two involved units over one or more inter-unit links.

The ISPBX supports V.24 and X.21 interfaces for connecting DTEs. The interface is used to transfer information from the DTE to the CPU for establishing the path to the destination port and to transfer the user-information through the network after the connection is established.

Glossary

- DTE means Data Terminal Equipment, which can be a data terminal, printer, Personal Computer, or any similar piece of equipment.

- DCE means Data Circuit terminating Equipment, which can be a modem or one of the range of Philips SOPHO-SET, SOPHO-LAM or LAM.

A DTE can be connected to the ISPBX using one of the following connections:

- The DTE can be connected to an Analogue Line Circuit (ALC) via a modem. In this case the modem is the DCE.ISPBX (ALC) - MODEM - DTEIn this case the ISPBX does not know that a DTE is connected; it is only an extension with a DNR assigned. Such a DTE can make data calls by sending dial information to the ALC. The ISPBX establishes a transparent `analogue' speech channel with another ALC with a modem connected. After answering a normal modem-modem connection is available.The characteristics of the modem determine the interface type between DTE and modem, the dialling and answering capabilities (for the call set-up and clearing) and the actual data transmission of user-to-user information (during the data transfer phase). The analogue part of the connection is often a limiting factor.

- The DTE can be connected to a Digital Line Circuit (DLC) via a SOPHO-SET, SOPHO-LAM or LAM. In this case the SOPHO-SET, SOPHO-LAM or LAM is the DCE.ISPBX (DLC) - SOPHO-SET, SOPHO-LAM or LAM - DTEThe DTE is identified by a DNR. Data is passed between DTEs in a transparent channel. The fully digital connection offers additional opportunities.The DTE is not connected directly to the digital line circuit but to a DCE. This can be a SOPHO-SET, SOPHO-LAM or LAM. The type of DCE determines the interface type between DTE and ISPBX network, the dialling and answering capabilities (for the call set-up and clearing) and the actual data transmission of user-to-user information (during the data transfer phase).The most common interface type between the digital line circuit and the DTE is V.24. Most information in this chapter will be dedicated to this type of interface. Most information will also be valid for the X.21 interface. In a special part in this chapter the special X.21 information will be discussed.

If an internal data party wishes to be connected to a party in a special type of data network and the ISPBX does not support the interface type then a gateway is required. Such a gateway can be connected to a DLC.

2.1. CONNECTING A DTE TO AN ALC

Digital peripherals can be connected to ISPBX using conventional analogue connections. This type of digital communication uses modems. The ISPBX does not know there is a digital terminal connected to the ALC and there is also no need to know. A transparent path between ALCs can be established irrespective the type of information transferred over the connection;

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voice or a modulated carrier with digital information.

The diagram below shows the connection of two DTEs using modems. Here a single unit configuration is illustrated (one switching network). A connection made between units uses 2 Mbps inter-unit links between the switching networks.

Figure 2-1 Analogue Connection between Terminals within the ISPBX.

The end user terminal is a DTE Equipment (DTE). The modem is a Data Circuit Terminating Equipment (DCE). A normal flat cable can be used for connecting both devices. By using two compatible modems two devices with any type of interface can be connected. The type of interface is of no interest as long as the ISPBX receives the call set-up information. For detailed information on the functioning of an interface, such as V.24, see the data communication literature.

The calling modem modulates the digital information from the calling data party on a carrier and this modulated carrier is transferred through the `analogue' network in the speech band. The receiving modem demodulates the incoming signal and the digital information is transferred to the destination data party. The two modems must be compatible with each other (use the same transmit and receive frequencies). In the case of full duplex communication Frequency Division Multiplexing is used. The calling data party uses the low frequency band (within the speech band) to send information while the called party uses the high frequency band as backward channel.

Depending on the type of modem, call set-up may be done using a normal telephone set (rotary dial or keytone), using keyboard dialling from the DTE or automatically under control of the DTE software. For example, V.25bis commands or AT-commands can be used for call set-up. The modem transfers the digits to the network as pulses or keytones. If a telephone

A DD A

DTE

V.24

DTE

DCE

64 kbps

5404CV0

Speech

Speech or modulated carrier Speech or modulated carrier

Compatible modemsCV0 CV0 : allowed

5404CV0

Speech

64 kbps

ALC

V.24MODEM MODEMSN

set is used for call set-up then the modem is connected to the line after the connection has been established.

A number of important points should be remembered to enable a modem-modem connection to be established:

- A modem can be connected to any type of ALC.- The ALC to which the modem is connected must be allocated a DNR.- The destination DNR must be included in the appropriate dialling tree of the calling party.- The traffic class of the calling party must at least have the same traffic class as the

destination number indicated in the dialling tree.- The IBSC 14=`SOPHO speech' should be allocated to the DNR.- The BSPT 14=`SOPHO speech' (or another voice BSPT) should be allocated to the DNR.- The CV of the DNR must be created as voice (CRCVAL or CHCVAL) and assigned to the

DNR (CHAGCV).- The compatibility value connection allowance between the CV of the calling and the CV

of the called party must be set to allowed (CHCVCA). For more information: see Appendix A.

- No facility class mark inhibits the connection.- The facilities offered by ̀ data protection' prevent a break-in attempt by another extension

or operator. A break-in to an established modem connection could disturb the data connection.

For more information on these mechanisms: see Facility Implementation Manual; Management.

2.2. CONNECTING A DTE TO A DLC/DTX

A DTE can be connected to the ISPBX using a Digital Line Circuit (DLC) or Digital Trunk and Extension (DTX) board and a DCE. The DCE is a SOPHO-SET, SOPHO-LAM or LAM.

The DLC-A, B, C, D or U is connected to a SOPHO-SET, LAM or PNT1 using a 2 wire, 2B+D S0 interface connection. This is a twisted pair connection over which two user (2B) channels of 64 kbps and a signalling (D) channel of 16 kbps are transferred. An additional 8 kbps synchronisation signal, makes the transmission speed 152 kbps. Existing twisted pairs (a-b wires, as used for analogue telephones) can be used for these data connections; no new wiring needs to be installed. The imperfections of the line are compensated for by using echo cancelling techniques for the transfer of digital information.

The DLC-I or DTX-I is connected to a SOPHO-SET or SOPHO-LAM using a 4 wire, ISDN 2B+D S{inf0} interface connection.

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For more information: see Hardware configuration Manual and Maintenance Manual, part 3: Board Interfaces and Strap Settings.

A number of important points should be remembered when making a connection between DTEs connected to DLCs:

- A DTE can be connected to the DLCs as listed earlier.- The DLC to which the DTE is connected must be allocated a DNR. In the case of a

SOPHO-SET, two DNRs must be allocated, one for the voice port and one for the data port.

- The destination DNR must be included in the appropriate dialling tree of the calling party.- The traffic class of the calling party must at least have the same traffic class as the

destination number indicated in the dialling tree.- The IBSC 00=`64 kbps unrestricted' should be allocated to the data DNR.- The BSPT 00=`64 kbps unrestricted' (or another data BSPT) should be allocated to the

data DNR.- The IBSC 14=`SOPHO speech' should be allocated to the voice DNR of a SOPHO-SET.- The BSPT 14=`SOPHO speech' (or another voice BSPT) should be allocated to the voice

DNR of a SOPHO-SET.- The data port of the SOPHO-SET, SOPHO-LAM or LAM used in the connection must be

correctly programmed. Both sides of the connection must be compatible.- The CV of the data DNR must be created as data (CRCVAL or CHCVAL) and assigned to

the DNR (CHAGCV). For a SOPHO-SET the CV for the voice DNR must be assigned as voice.

- The CV of a data DNR can be used to download the data port parameters of the SOPHO-SET, SOPHO-LAM or LAM. If this is required then the data port parameters are downloaded to the DNR using DOWNLD.

- The compatibility value connection allowance between the CV of the calling and the CV of the called party must be set to allowed (CHCVCA). For more information: see Appendix A.

- No facility class mark inhibits the connection.- Facility class mark FCM 12=`SOPHO-SET' must be allocated to the DNR of the DTE. For

a SOPHO-SET this must be done for both the voice and data DNRs. This indicates that the ISPBX must send call progress information (for instance ringing, answered, called by, call diversion address etc.), LED activation/de-activation signals and display information to the SOPHO-SET, SOPHO-LAM or LAM. Call progress information is used, for example, on the display of the SOPHO-SET, SOPHO-LAM or on the screen of the DTE.

2.3. DATA PORT

The data port of the SOPHO-SET, SOPHO-LAM or LAM acts as the interface between the

DTE and the ISPBX network and is therefore used as Data Circuit Terminating Equipment (DCE). A normal flat cable can be used for the connection.

The full digital connection for data communication within a FIN is illustrated in figure Figure 2-2 Full Digital Connection between Data terminals within the ISPBX.

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Figure 2-2 Full Digital Connection between Data terminals within the ISPBX.

The data port takes care that the user data (and some control signals if required and possible) is sent to the destination DTE. The conventions for the interface type only apply to the

DNR=5401CV=3, Data

64 kbps userchannel in 2B+D line

64 kbps userchannel in 2mbpsUSI / USO lines

DNR=5402CV=3, Data

DNR=5403CV=3, Data

DNR=5404CV=3, Data

DNR=5405CV=3, Data

DNR=5407CV=3, Data

DNR=5406CV=3, Data

DNR=5408CV=3, Data

DNR=5301CV=0,Speech

DNR=5302CV=0,Speech

CV3 - CV3 : allowedCV3 - CV0 : not allowed

V.24

V.24

LAMDCE

SOPHO-LAMDCE

SOPHO-LAMDCE

SOPHOSETDCE

SOPHOSETDCE

V.24

V.24

V.24

V.24

V.24

V.242B+D 2B+D

64 kbps

64 kbps

64 kbps

64 kbps

64 kbps

64 kbps

DTE DTE

DTE

DTE

DTE

DTE

DTE

DTE

64 kbps

2B+D

2B+D

2B+D2B+D

2B+D

2B+D2B+D

DCE DCE

SN

SN

SN

SN

SN

DLC/DTX-I

DLC/DTX-I

DLC/DTX-I

DLC/DTX-I

DLCPNT-1

DLC/DTX-I

DLCPNT-1

SN

interface between the DTE and the data port; NOT between the two DTEs.

Before a data call can be established, the data port must know if the DTE is ready to send or accept data. Therefore the normal on-line operations must be performed (V.24: CT 108 and CT 107 procedure; X.21: C and I procedure).

In the dialling phase the destination number is received by the DCE either from the keypad (not for the LAM) or from the connected DTE (either from the terminal keyboard or from the software program). The DCE transfers the number to the DLC-controller using a protocol-message in the D-channel. The DLC-controller initiates a call set-up request to the PPU and further to the CPU using the normal Internal Message Protocol (IMP).

For more information on the D-channel protocol: see Facility Implementation Manual; Networking and Routing.

If the call is allowed (number analysis, traffic classes, CV allowances and facility class marks) the ISPBX sends ringing current to the destination data port. The called data port receives a string from the CPU with the calling party identification. If required this string can be passed to the DTE.

If the called party answers the call, a transparent 64 kbps connection between the calling data port and the destination data port is established. If the two ports are located in the same unit only one switching network is involved. If the ports are located in different units, the 64 kbps connection is established between two or more switching networks connected together by a 64 kbps timeslot in 2 Mbps inter-unit links. For full duplex communication a reversed path from the called to the calling data port is also established. The calling data port receives a message to inform the port that the call has been answered.

After the transparent connection is established, the ISPBX is not involved in the data call any more until one of the data ports sends a message that the data call has finished. The ISPBX will then break down the connection.

The set-up of the complete data port can be defined by of programming the interface parameters. These include transmission speed and mode, separate signals of the interface control, method of data rate adaption, method used for dialling and the character format. Programming can be performed locally (using the keypad of the SOPHO-SET or SOPHO-LAM or by using the keyboard of the DTE) or remotely (by downloading the data compatibility value). The exact options available depend on the SOPHO-SET, SOPHO-LAM or LAM.

- DTE initiates activity.If the DCE is idle (i.e. not busy with a data connection), the DTE is able to communicate with the microprocessor of the DCE for dialling or data port programming. For local

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programming of the data port from the DTE keyboard, the DTE must be on-line (for instance, by setting the CT108 signal of the data port on).The microprocessor of the DCE prompts the DTE for input that can be dial information or a special command to enter programming mode. If keyboard dialling is selected then a number or name can be entered for dialling. If V.25 bis or AT-command dialling is selected, the microprocessor interprets the entered call set-up request and returns the result to the terminal.After the entry of dial information the microprocessor uses the D-channel protocol to send the dial information towards the ISPBX. After the destination party has answered the call, the data rate adaptor starts sending and receiving the frame pattern. After synchronisation the microprocessor connects the DTE to the data rate adaptor and the transparent DTE-DTE connection is established. If the user transmission rate is 64 kbps no synchronisation phase is necessary and the terminal is switched to the data rate adaptor when the opposite party has answered.

- ISPBX initiates activity.The microprocessor of the DCE is able to communicate with the CPU using D-channel messages. If an idle data party is called, the microprocessor receives a call set-up message. If required, the calling party identification (part of the call set-up message) can be sent to the DTE.The incoming call can be answered automatically (DCE answers the call autonomously) or manually (DTE answers the call). The data rate adaptor starts sending and receiving the frame pattern. After synchronisation the microprocessor connects the DTE to the data rate adaptor and the transparent DTE-DTE connection is established. If the user transmission rate is 64 kbps no synchronisation phase is necessary and the terminal is switched to the data rate adaptor when the opposite party has answered.

Note: If the data port supports synchronous communication, this only applies to the user - user data transfer phase. The communication between the DTE and the DCE is asynchronous and is used for programming and dialling the destination number. After the connection has been set-up to the destination DTE the transmission mode can be switched over to synchronous communication. If the DTE is not able to perform the switch-over the connection set-up can be performed automatically using the hot line facility.

A schematic overview of the data port configuration and its place in the SOPHO-SET, SOPHO-LAM or LAM is illustrated in the following figures.

Figure 2-3 Data port configuration within LAM 308 and LAM 309.

Figure 2-4 Data port configuration within SOPHO-LAM P375.

INTERFACECONTROL

INTERFACECONTROL

µP ECHOCANCELLER

2B+D152 kbps

Keyboard diallingData port programming

LAMPS

MEMORY

DATA RATEADAPTION

DATA RATEADAPTION

64 kbpsB-channel

V.24X.21

V.24X.21

16 kbpsD-channel

64 kbpsB-channel

MULTIPLEXER

INTERFACECONTROL

µP2B+D152 kbps

Keyboard diallingAT command diallingV.25bis diallingData port programming

LAMPS &DISPLAY

KEYPAD

MEMORY

DATA RATEADAPTION

64 kbpsB-channel

V.24

16 kbpsD-channel

MULTIPLEXER

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Figure 2-5 Data port configuration within SOPHO-SET 308, S375 D, P375 D and P370 D.

2.3.1. Interface Control and Data Rate Adaption

There are two systems of data transfer:

• With Data Rate AdaptionIf the transmission speed between the two DTEs is less than 64 kbps then the data rate must be adapted. Also some of the control signals of the interface between the DCE and the DTE can be transferred. The two DCEs use a frame structure to communicate with each other. The user data and interface control signals are located in fixed positions within that frame. The data rate adaption methods supported by SOPHO-SET, SOPHO-LAM and LAM are summarised below.

INTERFACECONTROL

µP ECHOCANCELLER

2B+D152 kbps

(SOPHO-SET 308and

S375 D only)

DATA RATEADAPTION

ANALOGUEDIGITAL

CONVERTOR

AUDIOINTERFACEHANDSET

64 kbpsB-channel

V.24

16 kbpsD-channel

64 kbpsB-channel

MULTIPLEXERLAMPS &DISPLAY

KEYPAD

MEMORY

Keyboard diallingAT command diallingV.25bis diallingData port programming

Table 2-1 Rate Adaptation Methods.

First the two data ports try to synchronise using a synchronisation pattern in the frame structure. If this pattern is detected without errors, then synchronisation is established. Synchronisation must be achieved in both directions. Once synchronisation is established the user-data and the interface control signals can be transferred between the two parties and the 64 kbps transparent channel is available to the DTEs.Each DCE receives the relevant interface signals (control signals and the user data) from the DTE and inserts them into the correct frame position in the 64 kbps user channel. This user channel is multiplexed by the DCE into the 152 kbps 2B+D line to the DLC. The DLC-line interface demultiplexes the 64 kbps user channel from the 2B+D line and inserts it in a timeslot in the 2 Mbps highway to the PSC/PMC. The 64 kbps signal is transferred to the opposite DLC, via the PSC/PMC and the switching network (and, if necessary, inter-unit links). The receiving DLC extracts the 64 kbps user channel from the 2 Mbps highway and multiplexes it into the user channel of the 2B+D line to the destination DCE. The data and control signals are extracted from the 2B+D line by the DCE and passed to the DTE. A transparent digital path has thus been established between the two DTEs.Data rate adaption is performed by a dedicated chip in ERGOLINE, SOPHO-SET, SOPHO-LAM or LAM; for SOPHO-SET, SOPHO-LAM or LAM the OQ 1505 or the OQ 1509. A summary of the most important features of these chips is given below.

PROPRIETARY X.30 V.110

Synchronous sampling frequency: 96kHz - -

Bits per frame : 32 80 80

Data : 24 48 48

Synchronisation : 4 17 17

Synchronisation status : 1 - -

State of CT105 / CT109: 3 2 2

Speed : - 3 3

NIC : - 3 3

600/1200 bps synchronisation adaption: - 1 1

State of CT108 / CT107: - 4 4

Flow control (CT106): - 2 2

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DATA OQ1505 OQ1509 Ergoline

Used in : LAM 308 SOPHO-SET S375 D

D340 with V.24 data port

LAM 309 SOPHO-SET P375 D

SOPHO-SET 308 SOPHO-SET P370 D

MLU SOPHO-LAM P375

Data rate adaptions supported:

Philips proprietary Philips proprietary

X.30 X30

V.110 V.110

Synchronous speeds supported:

600 600

1200 1200

(bps) 2400 2400

4800 4800

9600 9600

19200 19200

38400 38400

48000 48000 48000

56000 56000 56000

64000 64000 64000

Asynchronous speeds supported:

50

75

(bps) 110

150

200

300 300 300

600 600 600

1200 1200 1200

1200/75 1200/75

Table 2-2 Summary of Data Rate Adaptors.

• Without Data Rate AdaptionIf the transmission speed between the two DTEs is 64 kbps, then the full data channel is used for transferring user information; no control signals can be transferred. Since no control signals are transferred no synchronisation can be applied. The DTEs themselves must use some kind of frame structure to interpret the digital information.The DCE receives the user-data from the DTE and inserts it in the 64 kbps user channel. The user channel is multiplexed by the DCE into the 152 kbps 2B+D line to the DLC. The DLC-line interface demultiplexes the 64 kbps user channel from the 2B+D line and inserts it in a timeslot in the 2 Mbps highway to the PSC. The 64 kbps signal is transferred to the opposite DLC, via the PSC/PMC and the switching network (and, if necessary, inter-unit links). The receiving DLC extracts the 64 kbps user channel from the 2 Mbps highway and multiplexes it into the user channel of the 2B+D line to the destination DCE. The data is extracted from the 2B+D line by the DCE and passed to the DTE. A transparent 64 kbps digital path has thus been established between the two DTEs.

2.3.2. Profiles

This feature is only available in the SOPHO-SET S375 D, SOPHO-SET P375 D and the

75/1200

2400 2400 2400

3600

4800 4800 4800

7200

9600 9600 9600

12000

14400

19200 19200 19200

38400 *) 38400

48000 *)

56000 *)

64000 *)

*) Speeds higher than 19200 are not supported by LAMs or SOPHO-SET

DATA OQ1505 OQ1509 Ergoline

19

20

SOPHO-LAM P375.

Two data ports are only able to communicate correctly with each other if they use the same data port set-up. This is:

- Transmission mode (synchronous/asynchronous);- Conversation mode (full/half duplex);- Transmission speed;- Data format (byte length, stop bits, parity);- Terminal rate adaption method;- Terminal rate adaption options (flow control, Network independent Clock).

Only in this case are the data bits and the control signals transmitted and received in the same fixed positions in the frame structure.

It may be necessary for a DTE to be connected with other DTEs employing different data port set-ups. The use of `data profiles' makes it possible to connect normally incompatible parties.

A data profile is a data port set-up that can be used for the duration of a single data call. The profile is used to temporarily change the set-up of the local data port according to a set-up as used by another remote DTE. A data profile contains a complete data port set-up.

Four profiles can be defined. A profile must also be allocated to an entry in the name directory of the DCE.

When either an incoming call from or an outgoing call to another DTE is made, the DCE automatically changes the data port set-up to that of the profile; the two data ports are compatible.

When a call is initiated using the name directory and a profile is assigned to the name then the data port set-up is adjusted according to the information in the profile. With an incoming call, the DCE checks the received calling party identification. If the received number is stored in the directory and a profile is assigned to it, then the data port set-up is adjusted according to the information in the profile.

The information in the profile is only valid for the duration of one data call. After releasing the call, the set-up of the data port is restored to the local programming as was used before the profile changed the set-up.

More details on profiles are contained in the User Guide/Data Guide of the DCE.

2.4. X.21

X.21 is a protocol where the data transmission between the DTE and the DCE is synchronous. The transmission speeds between the DTE and DCE can be assigned between 600 and 64000 bps. The physical interface of X.21 comprises 6 lines: T-transmit data, R-receive data, S-signal element timing, B-byte timing, C-control, I-indicator.

The control (C) and indicator (I) lines perform the line signalling while the register signals (like dialled number) are transferred via the transmit (T) and receive (R) lines. The data on the transmit and receive lines, which is dedicated for the call control, is according to the International Alphabet No. 5 and has odd parity. For character synchronisation each call control data block is preceded by at least two SYN characters (Hexadecimal `16').

The connection of X.21 terminals to the SOPHO network is illustrated below.

Figure 2-6 X.21 Connections.

Two dialling options are offered for the LAM 309. The option is selected by an OM command parameter when creating the CV.

• Switched lineThe destination is `dialled' and a connection is made according to one of the following methods: - The LAM user `dials' the destination using a keyboard dialling command. The LAM

analyses the command and sends a D-channel message.- The number that is to be dialled can be stored in the LAM 309. When the DTE initiates

a `direct call', the LAM sends the stored number.(The direct call address, of up to 30 digits, can be downloaded to the LAM. For this purpose the DNR of the data port is assigned to a function key menu. In this menu the direct call address is programmed under function key number 0. After downloading to the DNR of the data port the direct call address is stored in the LAM.)

• Leased line

DNRCV

DNRCV

X.21

X.21

2B+D64 kbps

2B+D64 kbps

IMP64 kbps

IMP64 kbps

LAM309

LAM309

DLC

DLC

SN

21

22

The DNR of the LAM is configured as a `hot line'. When the DTE goes on-line, the LAM sends a message to the ISPBX. The ISPBX now initiates the hot line facility.

The ISPBX establishes a transparent connection between the DLC related to the B-channel of the dialling X.21 party and the DLC related to the B-channel of the internal X.21 destination. A synchronised frame structure is established in the B-channel. In this frame structure the user information and interface control signals are transferred from the sending to the receiving X.21 DTE.

After the call establishment phase, the ISPBX sends a message to the LAM. The two X.21 DTEs (synchronous) now try to synchronise. After synchronisation, the transparent data path is available.

A call is cleared either manually via the LAM or the DTE or by data guarding. In the latter case the LAM monitors the transmit and receive lines of the X.21 interface. If there is no activity on the lines during a specified time period, the LAM clears the call automatically. The data guarding option and the time limits can be specified in the CV related to the DNR. This can then be downloaded to the data port.

The parameter setting for the X.21 interface is described in appendix A.

2.5. GATEWAYS

This section describes the connection of a gateway server to the ISPBX network, but not the gateway server itself.

An internal data party may wish to be connected with a special type of data network. If the ISPBX does not support the interface type used within that network then a gateway is required. The internal party establishes a connection to the gateway server via which it transfers user-information. The gateway server takes care that the user-information is delivered to the data network in the correct format.

A gateway server is usually connected to a V.24 or X.21 interface of a LAM as illustrated below.

Figure 2-7 Gateway to Data Network.

The ISPBX data party dials (as for an internal data calls) the DNR of the LAM circuit which is connected to the gateway server. The gateway server answers the call. Now a transparent connection is established between this data party and the gateway server. The data party then selects the destination data party using, for instance, post dialling. The gateway server takes care of the connection through the data network. The gateway server now performs the conversion between the two interface types. The ISPBX data party can now communicate with the external data party, via the gateway server, using a protocol that is not supported by the ISPBX itself.

The LAMs which are connected to the gateway server can be assigned to a group arrangement with group hunting. In this case, the data party does not have to dial a free LAM-gateway but only the group DNR. Group hunting ensures that a free LAM-gateway circuit is accessed.

2.6. BASIC SERVICE PROFILES (BSP)

A Basic Service Profile is the combination of a DNR and a Basic Service Profile Type (BSPT) and is identified by a Basic Service Profile - Identifier (BSP-ID). This BSP-ID is assigned to a line circuit by OM: CHDNRC

One extension circuit (EHWA) can have several BSP-IDs assigned. These BSP-IDs may have different DNRs and different BSPTs.

A call to this circuit will be checked for compatibility. If the destination DNR and the IBSC of the caller match with more than one BSP-ID, the BSP-ID with the lowest numbered BSPT is selected.

A call, set up by a non-ISDN extension, will always use the BSP-ID with the lowest numbered BSPT. An ISDN extension, however, can differentiate between BSP-IDs.

DNRCV

DNRCV

V.24 / X.21 V.24 / X.212B+D

64 kbps2B+D

64 kbpsIMP

64 kbpsIMP

64 kbpsLAM LAM

GATEWAYSERVER

Other interface typese.g. X.25

Datanetwork

DLC DLC

SN

23

24

This setup can lead to the following applications:

This setup is very useful for a SOPHO-SET which uses B channel 0 for voice and B channel 1 for data, if there is a follow-me from BSP-ID0 to BSP-ID1. This configuration allows the extension to work with one DNR only, namely 2400. Voice calls to 2400 are connected to B channel 0 directly, whereas data calls are re-directed (because of the follow-me) from 2400 to 2401, which uses B channel 1. The follow-me relationship can only be changed by Operational Maintenance commands and not by dialling facility codes at the telephone set, because this only affects BSP-IDs for voice.

If callers must be able to discriminate between parties at an S{inf0} bus with the same service identifier, the facility Multiple Subscriber Number (MSN) must be used.

Example 2 : BSP-ID discriminates between a voice and a FAX call. An analogue telephone set has two BSP-IDs:

- DNR:2400 with BSPT:95 (voice/possibly voice)- DNR:2400 with BSPT:06 (telefax4)

The FAX machine has the following BSP-ID:

- DNR:2401 with BSPT:06 (telefax4)

A follow-me re-directs an incoming FAX call to DNR 2401, whereas a voice call goes directly to the analogue telephone. (see example 1 for additional remarks)

2.7. ISDN TERMINALS

See Facility Implementation Manual for Voice Facilities, chapter "S{inf0} Bus Terminals".

Example 1 : a voice/data terminal connected to an S0 bus:B channel 0 : - BSP-ID0=2400-95 (voice/possibly voice)

- BSP-ID1=2400-96 (data)B channel 1 : - BSP-ID1=2401-96 (data)

3. DATA COMMUNICATION OVER A ROUTE

In the ISPBX a DTE can be connected via a modem/ALC or via a DLC/SOPHO-SET, SOPHO-LAM or LAM as discussed in chapter 2. If the DTE requests a connection to an external DTE (i.e. one connected to another PBX or to the PSTN) then a trunk or tie-line must be used. An incoming data call, initiated by an external DTE, also uses a trunk or tie-line.

For an outgoing data call a connection to an external DTE can be established by dialling a trunk access code to a specific destination followed by the external number of the DTE.

For an incoming call, dial information (DDI) is received over the trunk or tie-line. By analysing this information in an analysis tree related to the route the connection set-up to an internal DTE is possible. If the connection set-up is performed using a speech connection before switching over to modems, both incoming and outgoing calls can be made with assistance of the operator.

The trunk line involved can be assigned to an analogue or to a digital route. This distinction is used in this chapter. Both a DTE connected via a modem to an ALC or a DTE connected via the data port of a SOPHO-SET, SOPHO-LAM or LAM to a DLC/DTX can gain access to the trunk line. For both types of parties the data communication aspects over an analogue route and over a digital route are discussed.

A number of trunks or tie-lines can be grouped into bundles, a number of bundles can be grouped into routes and a number of routes are related to a destination. The terms `line', `bundle', `route' and `destination' are used in OM for the allocation of various parameters.

In this chapter only the V.24 interface is described. For all other types of interfaces a gateway server has to be used. The connection between the DTE and the server is usually as for an internal data call and is therefore discussed in chapter 2.

For more information about the routing aspects: see Facility Implementation Manual; Networks and Routing.

3.1. DATA COMMUNICATION OVER AN ANALOGUE ROUTE

Various types of Analogue Trunk Units (ATUs) are used to connect ISPBX to the public network. There are many types to cater for the different transmission characteristics which are used throughout the world. All ATUs are used in the same way, as far as data communication is concerned.

25

26

3.1.1. Data Terminal Connected to an ALC

For a DTE connected to an ALC via a modem, the situation is straightforward. Because the output of the modem is an analogue signal it is possible to connect a modem directly to an ALC as indicated in figure Figure 3-1 Analogue Connection to an Analogue Trunk.. The digital information of the terminal is converted into an analogue signal by the modem and offered to the ALC. The ALC converts the analogue signal (carrier with the digital user information) into a digital 64 kbps signal which is switched through the FIN. The ATU converts the digital signal back into an analogue signal. The analogue signal on the trunk line now is the same analogue signal (modulated carrier) as at the modem side. The connection is formed between the internal modem and the modem of the external DTE.

Figure 3-1 Analogue Connection to an Analogue Trunk.

Two types of modems can be used:

- Automatic dialling modem.If the modem supports V.25 bis or Hayes commands, the user can type the trunk access code and the external number directly from the DTE for an outgoing call. The modem transfers this information as impulses or keytones to the ALC.

- Manual dialling modem.The user must dial the destination DNR from a telephone set connected to the modem. The telephone set transfers the dial information to the ALC as impulses or keytones. Once the `speech' path to the called party is established, the telephone line is switched through to the digital part of the modem. With a incoming data call the extension starts ringing and the extension user must answer the data call and switch the telephone line to the digital part of the modem. In this configuration the telephone can also be used for normal speech, although not at the same time a data connection is present.

Most modems offer an automatic answering option.

When the path is established the modems at both sides try to synchronise and if successful the

V.24

Modulated carrier (or speech)

TrunklineALC

IMP64 kbps

IMP64 kbps* *

*

DNRCV ATU CV

MODEMSN

data connection is present. The DTEs can send any type of digital information.

To make the data call with an external DTE possible the following conditions must be fulfilled:

- The modems must be compatible with each other.- The trunk access code must be included in the applicable dialling tree for the DNR for

outgoing callsand/orthe DNR must be included in the applicable dialling tree for the incoming traffic over the route (or assisted).

- The traffic class of the DNR must be sufficient to dial the trunk access codeand/orthe traffic class of the incoming route must be sufficient to dial the DNR.

- The CV-DNR to CV-trunk line connection allowance must be set to allowed (both ways). CVs are allocated to routes, all lines in the route have the same CV.

- The external number must be included in the DDO-tree.- The traffic class of the DNR must be sufficient to dial the external number.

Note: The last two conditions can be avoided for outgoing calls if the route option `direct switch through' is true. No number analysis is performed on the external number any more. After the trunk access code the speech path between the calling party and the trunk is established. The dialled digits for the external number are not regenerated by the ISPBX any more. The user can only dial an external number with keytones. The keytone information is directly transferred over the speech path to the opposite exchange.

3.1.2. Data Terminal Connected to a DLC/DTX (CONVERTORS)

A modem is required when a DTE is connected via a SOPHO-SET, SOPHO-LAM or LAM to a DLC/DTX, and a connection has to be made over an analogue trunk or tie-line. In this situation the signal from the DTE has to be modulated by a modem so it can be transferred over an analogue line. This modem interconnection is used in the following two configurations (see figure Figure 3-2 Leased Line and Switched Line configuration.):

- the leased Line configuration;- the switched line configuration.

27

28

Figure 3-2 Leased Line and Switched Line configuration.

These configurations are made by using a MLU or a SOPHO-LAM P375.

You can make a choice between the MLU and SOPHO-LAM convertor configuration. Generally you can make a choice based on the following characteristics:

• MLU convertor configurationAdvantages: - support of all synchronous speeds up to 64 kbit/s;- support of automatic convertor interconnection (only the destination DNR has to be

dialled);Disadvantages: - V.110 and X.30 Data Rate Adaption are not supported (Proprietary only).- Hayes modems are not supported because the modem has to operate in the CT108.1

mode.• SOPHO-LAM convertor configuration

Advantages:

V.24

V.24

V.24

V.24

DCE

DCE

DLC/DTX

DLC/DTX

ATU

MODEM

MODEM

ISPBX

ISPBX

Modulated carrier.

DCE-SOPHO-SET, SOPHO-LAM or LAM

Leased line configuration

Leased line

Switched line configuration

Trunkline

1

1

1

2

2

2

- support of almost all modems (including Hayes modems);- support of all current asynchronous speeds up to 19200 bits/sec;- support of V.110, X.30 and Proprietary Data Rate Adaption.Disadvantages: - full support of only three synchronous speeds (4800, 9600 and 19200 bits/s);- automatic convertor interconnection is not possible (convertor DNR and destination

DNR have to be dialled).

Leased Line Configuration with MLU

For trunk or tie-lines which are restricted for data use only, the line is connected directly to the modem. Voice calls are not possible over such lines. For this type of connection set-up the same requirements of number analysis, traffic classes and compatibility values must be fulfilled as for the DTE connected via a modem to the ALC.

In this case no ATU is needed and also no path from the MLU to the ATU through the switching network has to be set-up. The configuration of such a leased line connection is shown in figure Figure 3-3 Digital Connection to an Analogue Trunk with MLU Convertor (Leased Line).

Figure 3-3 Digital Connection to an Analogue Trunk with MLU Convertor (Leased Line).

Call progress is as follows:

- For an outgoing data call. When a DTE dials the trunk access code to the destination a free line (modem) is selected in the route to that destination and a direct data connection is established (a modem-modem connection). It is not possible to send additional dial information to the external network using the MLU and modem.

- For an incoming data call. When the modem is idle and detects a carrier on the line, an incoming seizure is initiated. It is not possible to receive additional dial information. The

V.24 2B+D V.24IMP

64 kbpsIMP

64 kbps

Trunkline

DCE DLC/DTX

MLU

SN

2B+D, B=64kbps, user channel.

Modulated carrier.


1

1

2

2

MODEM

29

30

route behaves like a route without DDI. A connection set-up to an operator (not very useful if digital information is directly sent over the trunk line) or permanent line extension (DTE) is possible.

This configuration implies that the MLU must be treated quite differently now because the analogue interface of the MLU, which is normally connected to the Modem, is not used any more. Now the MLU must be defined as a kind of ATU with a maximum of four trunk lines.

The following specifications apply for a MLU in leased line configuration:

- The MLU has to be projected with board type 22; signalling group 16XX; HW-type 255. The signalling group depends on the data speed and the direction of the call set-up.

- The circuits on the MLU are assigned a line number. This line is related to a bundle and the bundle to a route. This route is related to a destination which can be reached using a normal trunk access code. For more information on the line and routes: see Facility Implementation Manual; Networking and Routing.

- The outgoing route option Direct Switch Through must be set to true. The ISPBX does not wait for an answer signal over the `trunk line' but switches the trunk line directly to the destination party.

For more information on the MLU and leased lines: see Appendix B.

Leased Line Configuration with SOPHO-LAM P375

A SOPHO-LAM P375 convertor configuration can be used instead of an MLU. The configuration for such a leased line connection is shown in figure Figure 3-4 Digital Connection to an Analogue Trunk with SOPHO-LAM Convertor (Leased Line).

Figure 3-4 Digital Connection to an Analogue Trunk with SOPHO-LAM Convertor (Leased Line).

The DLC/DTX in this figure is one of the following boards:

- a DLC-I;- a DTX-I;- a DLC-U/PNT1 (release 1 or 2) combination;- a DLC-A(B)/PNT1 (release 1 or 2) combination;- a DLC-C(D)/PNT1 (release 1 or 2) combination.

An important difference between the SOPHO-LAM convertor configuration and the MLU convertor configuration is that the SOPHO-LAM configuration is projected as an extension and thus acts like an extension (including all extension related facilities). So, the SOPHO-LAM convertor has NOT to be defined as a kind of ATU.

In the convertor configuration the SOPHO-LAM must operate in the DTE mode. In this mode a DCE (modem) can be connected to the V.24 port of the SOPHO-LAM. Normally the SOPHO-LAM operates in the DCE mode. The SOPHO-LAM is set in the DTE-mode using a special signalling group for projecting the DLC or DTX-I (see Appendix C). Note that a special cable must be connected between the SOPHO-LAM and the modem (see appendix C).

Note that the leased line configuration can be used for both incoming and outgoing calls (call setup direction). The convertor settings for both configurations are the same. The switched line configuration can NOT be used for both directions of call setup (see section 3.1.2. Data Terminal Connected to a DLC/DTX (CONVERTORS)).

The following selection mechanisms can be used to select the SOPHO-LAM convertor:

V.24 V.242B+D 2B+DIMP

64 kbpsIMP

64 kbpsDCE SOPHO-LAM

DLC/DTX-I

DLC/DTX

SN

AnalogueTrunkline

2 3

4

1 1

MODEM

2B+D,( B=64kbps, user channel.

Special cable (See appendix C)

SOPHO-LAM P375 release 3 in DTE mode (!)

Modulated carrier.


1

3

2

4

31

32

- automatic convertor interconnection by Predefined Destination Dialling (PDD);- automatic convertor interconnection by hotline;- convertor pool selection by group DNR;- individual convertor selection.

Automatic convertor interconnection by PDD is used for incoming leased line calls. The predefined destination is a fixed internal destination DNR stored in the LAM convertor. When the LAM convertor detects an incoming call (for example an incoming carrier), it automatically dials the DNR which is stored in it's memory. Please refer to the user manual of the SOPHO-LAM P375 for programming the LAM.

PDD acts almost the same as DDI. With DDI the destination information is the incoming dial information, while PDD uses the programmed dial information in the SOPHO-LAM.

Automatic convertor interconnection by hotline is used for incoming leased line calls. The fixed relation between the trunk line and the internal destination is defined by projecting a hotline using OM command CHHOTL. The originator DNR is the DNR of the SOPHO-LAM convertor.

Note that it is not always necessary to use a fixed destination for incoming leased line calls; when the SOPHO-LAM is programmed for keyboard dialling, the external calling party can dial a destination DNR. In this situation the calling party uses the keyboard dialling protocol of the SOPHO-LAM to dial the destination. So, when the convertor modem detects an incoming call (for example an incoming carrier), it initiates a call request to the SOPHO-LAM. After the call request and after the connection between the modems is established, the SOPHO-LAM waits for dial information. The calling party sends the destination DNR using it's keyboard, after which the SOPHO-LAM sets up the connection.

Convertor pool selection by group DNR is used to access a pool of convertors. The group represents a convertor pool. When an internal party dials a group DNR it will be connected to one of the convertors out of the pool. After dialling the group DNR, in case of a leased line connection, the calling party is automatically connected to the destination. So, no destination information is required. All convertors must have the same destination. Otherwise the calling party does not know to which destination the data call is made.

Individual convertor selection is used to access one single convertor. This way of selection is especially for maintenance actions, such as changing the settings of the modem.

Normally only the maintenance engineer is allowed to use individual convertor selection. A user should use convertor pool selection by group DNR.

A single convertor is selected by dialling the convertor DNR. Individual convertor selection is

done the same way as making an ordinary call.

A so called `maintenance terminal' can be used to change convertor settings. This terminal must be able to make an ordinary call to an individual convertor in order to change the modem settings. A maintenance terminal is for example a SOPHO-SET S375D with a terminal connected to it.

Figure 3-5 Example of a Maintenance Terminal connection (Leased Line).

In case of a leased line configuration only the modem settings can be changed using a maintenance terminal, NOT the SOPHO-LAM settings. The reason for this is that the maintenance terminal has access to the V.24 interface of the modem, from the SOPHO-LAM towards the modem and not the other way around. So, for example, the modem settings can be changed by using Hayes commands (this depends on the modem used).

In order to change the settings of the SOPHO-LAM the maintenance terminal must have acces to the V.24 interface of the SOPHO-LAM, from the modem towards the SOPHO-LAM. This is not the case in the leased line configuration. Therefore in the leased line configuration the maintenance terminal can not be used to change the SOPHO-LAM settings. Another method has to be used. For example by using the key pad of the SOPHO-LAM or by downloading the SOPHO-LAM.

To change the modem settings, the maintenance engineer has to dial the convertor DNR. After dialling this DNR the connection is made between the maintenance terminal and the individual convertor. When the modem supports Hayes commands, the modem settings can be changed using Hayes commands.

Normally users are not allowed to dial individual convertors. To prevent that users can dial


64 kbpsIMP


DLC/DTX-I

DLC/DTX

SN

AnalogueTrunkline

MAINTENANCETERMINAL

2 3

4

1 1

MODEM




Modulated carrier.


1

3

2

4

33

34

individual convertors, compatibility values can be used. It is also possible to use modems of which the settings can be protected with a password.

The convertor modem has to be configured as follows:

- Leased line configuration;- CT108 always ON;- CT107 indicates the state of the analogue connection (according to V.24);- Automatic answering ON;- modem operates in silent mode (result codes disabled).

With this configuration there is a permanent connection between the modems as long as the remote terminal is operational. So, the connection is only cleared when the remote terminal is switched off.


• Outgoing callWhen the calling party dials the converter group DNR, one of the convertors is selected and a connection is made between the calling terminal and the corresponding SOPHO-LAM. Because the connection between the modems is already present, the calling terminal is directly connected to the remote terminal.

• Incoming callWhen the remote terminal is switched on, the remote modem sets up a connection to the convertor modem. After the connection between the modems is established, the remote terminal is connected to the SOPHO-LAM. The remote terminal can initiate a call request by typing a character (CT103 as call request). After the call request the SOPHO-LAM sets up the connection to a fixed destination using PDD or hotline calling.

The following specifications apply for a SOPHO-LAM leased line configuration:

- It is not allowed to define a convertor pool which is a mixture of MLU convertors and SOPHO-LAM convertors;

- A convertor pool may be located anywhere in the Fully Integrated Network;- Each convertor type has its own programmable data rate adaption method; Philips

Proprietary, X.30 or V.110. When different data rate adaption methods are required then different convertor types have to be installed, or one SOPHO-LAM with different profiles.

Use the following procedure for projecting a SOPHO-LAM convertor for leased lines (please refer to the OM command manual for detailed information):

- Use the SOPHO-LAM P375 release 3 or upwards;- Use PPU package 144.4 or upwards;

- Assign a DLC/DTX board using OM command ASBRDS and the correct sub-signalling groups (ASPCTB) to operate the SOPHO-LAM in DTE mode (see Appendix C);

- Set the board and circuits in service condition INS using OM command SETINS;- Assign DNRs to the line circuits of the DLC/DTX to which the convertors are connected

using OM command CHDNRC;- Assign IBSC `64 kbit/s unrestricted' (IBSC=0) to the DNRs of the SOPHO-LAM

convertors using OM command CHDNRS;- Assign the correct Terminal Endpoint Identifier to the SOPHO-LAMs used (TEI=0 or

TEI=1; first or second B-channel respectively). For programming the TEI value refer to the Customer Engineer Manual of the SOPHO-LAM P375.

- Define a group of convertors (a convertor pool) using OM command CRGRPA. GROUP-PROPS:

GROUP-DISPLAY=0;SUPERVISOR-DNR and PARK-POS are not used;

- Download the CV information towards the SOPHO-LAMs using OM command DOWNLD;

- If required, project a Permanent Line Extension using OM command CHPLEX;- If required, project a hotline relation using OM command CHHOTL;- If required, program the predefined destination DNR in the convertor SOPHO-LAM;- Ensure that the convertor modem is configured for leased line operation;- Ensure that the convertor modem operates in the silent mode (result codes disabled) You

can set this option using Hayes command ATQ1;- Ensure that CT108 of the convertor modem is continously on (108.2 mode; Data

Terminal Ready);- Ensure that CT107 indicates the condition of the analogue line (normal operation

according to V.24 specifications).This means the following: - CT107 is OFF in the idle state;- CT107 goes OFF when the Hang Up process is started;- CT107 goes ON as soon as the connection set-up is started;- CT107 goes ON in the V.25(bis) dialog mode.

- empty group allowed = no;- group hunting = yes;- hunting sequence = fixed or cyclic;- automatic COB = yes or no;- call pickup = no;- pickup to group only = no;- observation group = no;- ACD = no.

35

36

You can set this operation using Hayes command AT&S1;- Connect the SOPHO-LAM to the modem with the special cable described in appendix C.

Switched Line Configuration with MLU

If the analogue trunk or tie-lines are to be used for both voice and data connections, then the line cannot be directly connected to a modem. For this situation a number of modems are installed as a common resource in a `modem pool'. When a DTE connected to a DLC/DTX requires a trunk or tie-line, the ISPBX automatically accesses a free modem in the pool and switches the modem into the connection. For this type of connection set-up a number of requirements must be fulfilled for number analysis, traffic classes and compatibility values. Except for the CV connection allowance check the same requirements must be fulfilled as for the DTE connected via a modem to the ALC.

Figure 3-6 Digital Connection to an Analogue Trunk with MLU Convertor (Switched Line).

The modem has to be connected to a Modem Line Unit (MLU) (see figure Figure 3-6 Digital Connection to an Analogue Trunk with MLU Convertor (Switched Line).). An MLU is a board in a Unit Group of a PM. It can control a maximum of 4 modems. Each modem can be connected between any analogue tie or trunk line and any digital line circuit via the MLU.

Modems of the same type are placed in a modem pool. When a modem is required ISPBX looks for an available modem of the correct type in a particular modem pool. ISPBX determines what kind of modem is required for the calling party. For example: synchronous or asynchronous communication, speed, full or half duplex. How the correct modem type can be determined, is discussed in appendix A.

Modems are defined within ISPBX as follows:

- The MLU has to be projected with board type 33; signalling group 16XX; HW-type 255. The signalling group depends on the data speed and the direction of the call set-up. The

V.24 2B+D V.24IMP

64 kbpsIMP

64 kbps

IMP64 kbps

CVIMP

64 kbps

AnalogueTrunkline

DCE DLC/DTX

ATU

MLU

SN


Modulated carrier.


1

1

2

2

2

MODEM

MLU acts as the DTE in this configuration and controls the unattended modem (DCE). For more information on the MLU and convertors: see Appendix B.

Modem pools are created as follows:

- One MLU can handle different modem types; on one MLU, the modems can belong to different modem pools; the modems belonging to one modem pool can be divided over different MLUs.

- In a modem pool all the modems must be of the same type. This is known as the `convertor type'. The convertor type number is created with the command CRCTYP.

- When the convertor type number of the modems in the modem pool has been defined, the location of the modems in this pool must be told to the ISPBX. This is done by relating a EHWA of a MLU circuit (where the same type of modem is connected) to a convertor type number with the command ASCONV.

- Now the system knows which types of convertors (convertor type numbers) are present and where a convertor of a certain type can be found. Which type of modem must be used, is determined in the `CV-A - CV-B - convertor type number' array. This array is defined with the command ASCVCT. With this command the modem type that must be used when a connection between an internal DTE and an analogue trunk line is defined.

- In a FIN the number of modem pools (different modem types) is limited by the network boundary NEBOUND 033 (max. size of convertor compatibility list).

- Per unit the maximum number of MLU boards (each board has 4 circuits) is limited by the boundary LOBOUND 054 (max. nbr. of modem line units).

Switched Line Configuration with SOPHO-LAM P375

A SOPHO-LAM P375 convertor configuration can be used instead of an MLU. The configuration for such a switched line connection is shown in figure Figure 3-7 Digital Connection to an Analogue Trunk with SOPHO-LAM Convertor (Switched Line).

Some display commands:DICTYP : display the created convertor typesDICONV : display relation convertor type -- convertor EHWADICVCT : display relation CV-A -- CV-B -- convertor typeThe erase commands:ERCONV : erases convertor EHWA (circuit must be in NIN)ERCTYP : erases convertor type (all convertors must be deleted first)

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Figure 3-7 Digital Connection to an Analogue Trunk with SOPHO-LAM Convertor (Switched Line).

The DLC/DTX in this figure is one of the following boards:

- a DLC-I;- a DTX-I;- a DLC-U/PNT1 (release 1 or 2) combination;- a DLC-A(B)/PNT1 (release 1 or 2) combination;- a DLC-C(D)/PNT1 (release 1 or 2) combination.

In the convertor configuration the SOPHO-LAM must operate in the DTE mode. In this mode a DCE (modem) can be connected to the V.24 port of the SOPHO-LAM. Normally the SOPHO-LAM operates in the DCE mode. The SOPHO-LAM is set in the DTE-mode using a special signalling group for projecting the DLC or DTX-I (see Appendix C). Note that a special cable must be connected between the SOPHO-LAM and the modem (see appendix C).

Note that it is NOT possible to use the SOPHO-LAM convertor configuration for both incoming and outgoing calls. The SOPHO-LAM convertor is used either for incoming calls or for outgoing calls. So, at least two convertor pools should be created, one for incoming and one for outgoing calls.

The reason for this is that Hayes modems send strings to the SOPHO-LAM. In some situations this can give problems. For example, during an incoming call the modem sends the string `RING' to the SOPHO-LAM. The SOPHO-LAM does not understand this `command'. The SOPHO-LAM echoes the string back to the modem, and the modem also does not understand the command `RING'. Therefore for incoming calls the convertor modem should NOT send

V.24 V..242B+D 2B+DIMP


DLC/DTX

IMP64 kbps DLC/

DTX

IMP64 kbps

IMP64 kbps

ALC

ATU

SN

AnalogueTrunkline

CV

2 3

4

4

1 1

MODEM

2B+D,( B=64kbps, user channe)l.



Modulated carrier.


1

3

2

4

response strings (silent mode). This is not valid for outgoing calls, because then the convertor modem should send response strings to the SOPHO-LAM.

So, the convertor settings for incoming and outgoing calls are different. Therefore at least two convertor pools should be created.

The following selection mechanisms can be used to select the SOPHO-LAM convertor:

- convertor group selection by group DNR;- individual convertor selection.

Convertor pool selection by group DNR is used to access a pool of convertors. The group represents a convertor pool. When an internal party dials a group DNR it will be connected to one of the convertors out of the pool. After dialling the group DNR the calling party has to specify the destination information. This destination information is NOT handled by the ISPBX; the ISPBX is transparent for the destination information dialled after the convertor group DNR. So, the destination information must be handled on application level (end to end communication between calling party and convertor). For example, when a modem supports Hayes commands the destination information is specified using the ATD <destination DNR> Hayes command (refer to the user manual of the modem).

Unlike `automatic convertor interconnection by CV', the IBSC of the internal calling party can not be used for addressing the destination. The SOPHO-LAM convertor uses the IBSC of the output of the convertor (ALC side) for addressing the basic service profile of the destination.

Individual convertor selection is used to access one single convertor. This way of selection is especially for maintenance actions, such as changing the settings of the modem or SOPHO-LAM. Normally only the maintenance engineer is allowed to use individual convertor selection. A user should use convertor pool selection by group DNR.

A single convertor is selected by dialling the individual convertor DNR. This is done in the same way as making an ordinary call.

After the convertor is selected, the calling party must specify the destination. This destination information is NOT handled by the ISPBX. So, the destination information must be handled on application level (end to end communication between calling party and convertor).

Just like the leased line configuration the settings of the convertor in a switched line configuration can be changed using a maintenance terminal. Figure Figure 3-8 Maintenance Terminal connection for changing SOPHO-LAM settings (Switched Line). shows the configuration which can be used to change the SOPHO-LAM settings.

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Figure 3-8 Maintenance Terminal connection for changing SOPHO-LAM settings (Switched Line).

Of course the SOPHO-LAM settings can also be changed by using the keypad of the SOPHO-LAM or by downloading the SOPHO-LAM.

To change the modem settings, the maintenance engineer has to dial the convertor DNR. After dialling this DNR the connection is made between the maintenance terminal and the convertor. When the modem supports Hayes commands, the modem settings can be changed using Hayes commands.


• Outgoing callSOPHO-LAMWhen the calling party dials the convertor group DNR (pool for outgoing calls), one of the convertors is selected and the calling party is connected to a convertor modem via the SOPHO-LAM. Then the calling party has to specify the destination DNR. Depending on the modem, Hayes commands and/or V.25bis commands can be used. For example the DTE dials ATD<destination DNR>. The convertor modem now sets up the connection via the ALC.

• Incoming callThe calling party dials the convertor group DNR (pool for incoming calls). This is the group DNR of the ALC circuits to which the convertors are connected. Then the calling party is switched through to the analogue side of a convertor modem. When the convertor modem is idle and operates in the automatic answering mode, it detects the incoming call and establishes the connection with the remote modem (automatic answering). Now the

V.24 V.242B+DIMP

64 kbps

IMP64 kbps

IMP64 kbps SOPHO-

LAMALC

ALC

DLC/DTX

SN2 31

MODEM

4

4

MODEM

MAINTENANCETERMINAL




Modulated carrier.

1

3

2

4

remote modem is connected to the V.24 interface of the SOPHO-LAM convertor. Then the calling party has to specify the destination DNR using one of the dialling methods offered by the SOPHO-LAM.

The following specifications apply for a SOPHO-LAM switched line configuration:

- It is not allowed to define a convertor pool which is a mixture of MLU convertors and SOPHO-LAM convertors;

- A convertor pool may be located anywhere in the Fully Integrated Network;- Each convertor type has its own programmable data rate adaption method; Philips

Proprietary, X.30 or V.110. When different data rate adaption methods are required then different convertor types have to be installed, or one SOPHO-LAM with different profiles;

- There is NO logical relation between the DLC/DTX and the ALC of the convertor. For example a status change of one of the circuits (four example as a result of SETOUT) does not result in a status change of the other related circuit;

- When the analogue party at the other side of the trunk or tie line clears the call, then the internal digital party is informed about this via the convertor;

- When the internal digital party clears the call, then the analogue party at the other side of the trunk or tie line is informed about this via the convertor;

- The modem must be able to handle the destination information from the calling party. For example Hayes or V.25 bis.

- During the convertor interconnection the ISPBX checks the IBSC/BSPT compatibility and the CV compatibility. When a convertor is selected then the call is proceeded with the service characteristics of the convertor output circuit. For example when a call is made via a DPNSS trunk, then the Service Identification Code (SIC) sent to the other party is derived from the projected IBSC of the convertor output circuit;

Use the following procedure for projecting a SOPHO-LAM convertor for switched lines (please refer to the OM command manual for detailed information):

- Use the SOPHO-LAM P375 release 3 or upwards;- Use PPU package 144.4 or upwards;- Assign a DLC/DTX board using OM command ASBRDS and the correct sub-signalling

groups (ASPCTB) to operate the SOPHO-LAM in DTE mode (see Appendix C);- Assign a ALC board using OM command ASBRDS:- Assign an ATU board using OM command ASBRDS;- Set the boards and circuits in service condition INS using OM command SETINS;- Assign DNRs to the line circuits of the DLC/DTX to which the convertors are connected

using OM command CHDNRC;- Assign DNRs to the line circuits of the ALC to which the convertors are connected using

OM command CHDNRC;- Assign IBSC `64 kbit/s unrestricted' (IBSC=0) to the DNRs of the DLC/DTX using OM

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command CHDNRS;- Assign IBSC `3, 1 kHz audio' (IBSC=2) to the DNRs of the ALC using OM command

CHDNRS;- Assign the correct Terminal Endpoint Identifier to the SOPHO-LAMs used (TEI=0 or

TEI=1; first or second B-channel respectively). For programming the TEI value refer to the Customer Engineer Manual of the SOPHO-LAM P375.

- Define a group of convertors for either outgoing traffic (DLC/DTX side) or incoming traffic (ALC side) using OM command CRGRPA. Use the following parameter settings:GROUP-PROPS:

GROUP-DISPLAY=0;SUPERVISOR-DNR and PARK-POS are not applied;

- Download the CV information towards the SOPHO-LAM using OM command DOWNLD;

- Ensure that the convertor modem clears the connection when the state of CT108 changes from ON to OFF.You can set this option using Hayes command AT&D2;

- CT107 indicates the condition of the analogue line (normal operation according to V.24 specifications).This means the following: - CT107 is OFF in the idle state;- CT107 goes OFF when the Hang Up process is started;- CT107 goes ON as soon as the connection set-up is started;- CT107 goes ON in the V.25(bis) dialog mode.You can set this operation using Hayes command AT&S1;

- For a convertor pool for incoming calls, set the convertor modems in the `silent' mode (no strings send to the SOPHO-LAM).You can set this option using Hayes command ATQ1;

- For a convertor pool for incoming calls, set the convertor modem in the automatic answering mode using Hayes command ATS0=1;

- For a convertor pool for outgoing calls, set the convertor modems in the `non-silent' mode (send strings to the SOPHO-LAM).

- empty group allowed = no;- group hunting = yes;- hunting sequence = fixed or cyclic;- automatic COB = yes or no;- call pickup = no;- pickup to group only = no;- observation group = no;- ACD = no.

You can set this option using Hayes command ATQ0;- Connect the SOPHO-LAM to the modem with the special cable described in appendix C.

3.2. DATA COMMUNICATION OVER A DIGITAL ROUTE

Various types of Digital Trunk Units (DTUs) are used to connect ISPBX to the public network. The different types are summarised in section 3.3. DIGITAL ROUTES

3.2.1. Data Terminal Connected to an ALC

A DTE can be connected to an ALC via a modem (see figure Figure 3-9 Analogue Connection to a Digital Trunk.). The ALC samples and digitises the analogue signal from the modem (modulated carrier) to a 64 kbps signal. The 64 kbps signal can be transferred to a DTU/DTX via 2 Mbps links and the switching network. The DTU/DTX inserts the digitised signal into a free timeslot in the digital trunk or tie-line. For full duplex communication the reversed path must also be established.

Figure 3-9 Analogue Connection to a Digital Trunk.

For an outgoing call the internal DTE must be allowed to dial the applicable trunk access code. For an incoming call the external party must be allowed to dial the ALC-DNR. The connection allowance between the compatibility value of the internal DTE and the compatibility value or the trunk or tie-line must be set to allowed. The external DTE must use a compatible modem.

3.2.2. Data Terminal Connected to a DLC/DTX

The data of an internal party is transferred between the DTE and a SOPHO-SET, SOPHO-LAM or LAM via a V.24 or X.21 interface. The digital information is inserted in a user (B)

V.24

Trunkline

IMP64 kbps

DNRCV

IMP64 kbps

ALC DTU/DTX

SN21

MODEM

Modulated carrier.1

2 Digitised modulated carrier in a 64kbps user channel.2B+D, (DTU-BA or DTX-I) or 30B+D (other DTUs). B = user channel.

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channel in the 2B+D line to the DLC/DTX. The signalling information, such as the called number, is transferred as a message in the D-channel of the 2B+D line.

If the call set-up information indicates an access code towards a destination which can be reached via a DTU/DTX route, the ISPBX searches for a free circuit (timeslot) in the route and sends a message to the external network in the signalling channel. After acknowledgement the transparent 64 kbps path between the DTE and the external network is established.

With an incoming call the ISPBX receives an incoming seizure of a DTU/DTX circuit. It receives further dial information in the signalling channel and this information is analysed in the DDI-tree related to the route. If there is no DDI-traffic on the route the call is directed to the operator or to a PLE related to the trunk line. After call set-up is completed a transparent 64 kbps path between the external network and the internal user is established.

The opposite DTE can be connected to the external network by a digital interface or by a modem. This gives rise to the following configurations:

- Opposite DTE connected to a digital interface.No modem connection in the ISPBX has to be used. The 64 kbps data signal from the DLC/DTX can be transparently switched through to a circuit of the DTU/DTX. Here the 64 kbps signal (with the user data incorporated) is inserted in a free timeslot in the 2 Mbps link to the external network. For full duplex communication the reversed path must also be established between the DTE and the DTU/DTX circuit.

Figure 3-10 Digital Connection to a Digital Trunk.

A fully digital connection between the ISPBX (internal) DTE and the external DTE is established.The internal DTE must be allowed to dial the applicable trunk access code or the incoming call must be allowed to dial the DLC/DTX-DNR. The allowance between the compatibility value of the internal DTE and the compatibility value of the DTU/DTX-route must be set to allowed (3).

- Opposite DTE connected to a modem.

V.24 2B+D


2B+D, (DTU-BA or DTX-I) or 30B+D (other DTUs). B=64kbps user channel.

IMP64 kbps

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DCE DLC/DTX

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1 2

The internal DTE must also use a modem. In this case the normal modem pool dialling as discussed earlier is used. The 64 kbps signal from the DLC/DTX is sent to a MLU. The digital information from the DTE is retrieved from the 64 kbps signal and sent to the modem. The analogue signal from the modem is digitised and the resulting 64 kbps signal transferred to the DTU/DTX. Now the digitised modulated carrier signal from the modem is inserted into a timeslot in the route. For full duplex communication the reversed path must also be established between the DTE and the DTU/DTX.A modem-modem connection between internal and external DTE is established although the signal is transferred between the ISPBX network and the external network in digital format.

Figure 3-11 Digital Connection to a Digital Trunk (with Modem).

The internal DTE must be allowed to dial the relevant access code or the incoming call must be allowed to dial the DLC/DTX-DNR. The connection allowance between the CV of the internal DTE and the CV of the route must be set to `allowed with convertor' (2). The relation between the CVs must indicate which type of modem is to be used.For more information: see the modem pool dialling part with the analogue trunk or tie-lines.

3.3. DIGITAL ROUTES

There are two types of digital routes supported in ISPBX:

- 30B+D (Primary Rate).A 2 Mbps digital trunk or tie-line offering 30 user channels (timeslots) of 64 kbps each. Timeslot 16 is used for the signalling information for all user channels. Timeslot 0 is used for synchronisation purposes.

- 2B+D (Basic Access).

V.24 2B+D V.24IMP

64 kbpsIMP

64 kbps

IMP64 kbps

IMP64 kbps Trunk

line

DCE DLC/DTX

DTU/DTX

MLU

SN


Digitised modulated carrier in a 64kbps user channel.2B+D, (DTU-BA or DTX-I) or 30B+D (other DTUs). B = user channel.


1

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2

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MODEM

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A 192 kbps digital trunk or tie-line offering 2 user channels (timeslots) of 64 kbps each. A 16 kbps channel is used for the signalling for both user channels. There is 48 kbps of overhead (synchronisation etc.).

Digital links are used to connect the ISPBX to other digital public or private networks. The physical interface between the digital trunk line and the ISPBX is formed by the Digital Trunk Unit (DTU) or Digital Trunk and Extension (DTX). There are a number of different DTUs, supporting various signalling systems. Some DTUs performs the conversion between the the digital link signalling and the internal message protocol (IMP) as used in the SOPHO ISPBX. For other DTUs this task is performed by an ISDN Protocol Handler (IPH). Several digital signalling systems are discussed in the following sections.

The DTU/DTX link is projected as a route to which a CV is assigned. Any internal party can be allowed to use a timeslot in the link for data communication or speech when the CV connection allowance is 3 (allowed).

- For an outgoing call. After dialling the access code to a destination which can be reached via the digital route, the ISPBX accesses a free timeslot in the DTU/DTX link and establishes a transparent connection between the switching network and the external network. The access code will be a trunk access code for connection to the public network or a network access code for connection within a private network.

- For an incoming call. For an incoming call (DDI) the number is analysed in the DDI-tree related to the digital route. If the number indicates an internal number, ringing current is sent to the extension. After answering the incoming call, a transparent connection between the external network and the internal party is established.

For more information on the routing aspects: see Facility Implementation Manual; Networks and Routing.

3.3.1. DASS 2 Route

A Digital Access Signalling System No 2 (DASS 2) link is a 2Mbps line, 30B+D (timeslot 16 is used for signalling, timeslot 0 is used for synchronisation). It is used for connection to a public network. The signalling protocol is handled by an IPH or DTU-PH.

For determining if the related users in both private networks are compatible, a special parameter is transferred over the DASS 2 link with incoming or outgoing calls. This parameter is the Service Indicator Code (SIC). The SIC is a two byte code which is derived from the IBSC of the ISPBX internal party. The SIC can be assigned as voice or data together with some additional values for data such as speed and parity.

- For an incoming call, the SIC is translated into an Internal Service Identifier (ISI). The ISI

comprises an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC is passed through to the destination port. The IBSC is used for compatibility determination.

- For an outgoing call, the calling port supplies an ISIC, which together with the ports IBSC form an ISI. The ISI is translated into a SIC and passed over the DASS 2 link.

The translation tables used are given in appendix A.

For more information on the routing aspects and on the Service Indicator Code: see Facility Implementation Manual; Networks and Routing.

3.3.2. ISDN Route

An ISDN link is used for connection to a private or a public network. The link can be either:

- A 2Mbps line, 30B+D (timeslot 16 is used for signalling, timeslot 0 is used for synchronisation). This requires a DTU-PH which handles its own signalling protocol.

- A 192kbps line, 2B+D (16kbps D channel used for signalling, 48kbps overhead). This uses a DTU-BA or DTX-I. The signalling protocol handled is by the DTU-PH or DTX-I.

For determining if the related users in both networks are compatible, a special parameter is transferred over the ISDN link with incoming or outgoing calls. This parameter is the External Service Indicator (ESI). The ESI is a two byte code which is derived from the IBSC of the ISPBX internal party. The ESI can be assigned as voice or data together with some additional values for data such as speed and parity.

- For an incoming call, the ESI is translated into an Internal Service Identifier (ISI). The ISI comprises an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC is passed through to the destination port. The IBSC is used for compatibility determination.

- For an outgoing call, the calling port supplies an ISIC, which together with the ports IBSC form an ISI. The ISI is translated into a ESI and passed over the ISDN link.



3.3.3. DPNSS No.1 Route

A Digital Private Network Signalling System No.1 (DPNSS No.1) link is a 2Mbps line, 30B+D (timeslot 16 is used for signalling, timeslot 0 is used for synchronisation). It is used for

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connection to a private network. The signalling protocol is handled by an IPH, DTU-PH, DTU-BA, DTX-I. The DTU-VC can be used for DPNSS as well, but is only suited for voice connections.

For determining if the related users in both networks are compatible, a special parameter is transferred over the DPNSS No.1 link with incoming or outgoing calls. This parameter is the Service Indicator Code (SIC). The SIC is a two byte code which is derived from the IBSC of the ISPBX internal party. The SIC can be assigned as voice or data together with some additional values for data such as speed and parity.

- For an incoming call, the SIC is translated into an Internal Service Identifier (ISI). The ISI comprises an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC is passed through to the destination port. The IBSC is used for compatibility determination.

- For an outgoing call, the calling port supplies an ISIC, which together with the ports IBSC form an ISI. The ISI is translated into a SIC and passed over the DPNSS No.1 link.



3.3.4. 1TR6 Route

A 1 Technische Richtlinie 6 (1TR6) link is used for connection to a private or a public network. The link can be either:


- A 192kbps line, 2B+D (16kbps D channel used for signalling, 48kbps overhead). This uses a DTU-BA or DTX-I. The signalling protocol handled is by the DTU-BA or DTX-I.

For determining if the related users in both networks are compatible, a special parameter is transferred over the 1TR6 link with incoming or outgoing calls. This parameter is the 1TR6 Service Indicator (1TR6-SI). The 1TR6-SI is a two byte code which is derived from the IBSC of the ISPBX internal party. The 1TR6-SI can be assigned as voice or data together with some additional values for data such as speed and parity.

- For an incoming call, the 1TR6-SI is translated into an Internal Service Identifier (ISI). The ISI comprises an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC is passed through to the destination port. The IBSC is used for compatibility determination.

- For an outgoing call, the calling port supplies an ISIC, which together with the ports IBSC form an ISI. The ISI is translated into a 1TR6-SI and passed over the 1TR6 link.



3.3.5. VN2 Route

A VN2 link is used for connection to a private or a public network. The link can be either:


- A 192kbps line, 2B+D (16kbps D channel used for signalling, 48kbps overhead). This requires a DTU-BA which handles its own signalling protocol.

For determining if the related users in both public or private networks are compatible, a special parameter is transferred over the VN2 link with incoming or outgoing calls. This parameter is the VN2 Service Indicator (VN2-SI). The VN2-SI is a two byte code which is derived from the IBSC of the ISPBX internal party. The VN2-SI can be assigned as voice or data together with some additional values for data such as speed and parity.

- For an incoming call, the VN2-SI is translated into an Internal Service Identifier (ISI). The ISI comprises an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC is passed through to the destination port. The IBSC is used for compatibility determination.

- For an outgoing call, the calling port supplies an ISIC, which together with the ports IBSC form an ISI. The ISI is translated into a VN2-SI and passed over the VN2 link.



3.3.6. Channel Associated Route

A Channel Associated link is a 2Mbps line, 30B+D (timeslot 16 is used for signalling, timeslot 0 is used for synchronisation). The signalling protocol is handled by the DTU-CA or DTU-PU. It is used for connection to a public network.

No special parameters are transferred over the CA-link with incoming or outgoing calls to

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determine if the related users in both networks are compatible.

For an incoming call the fixed IBSC `3.1 kHz-audio non-ISDN' (IBSC=3) is passed to the destination port and used for conectivity checking.

For more information on routing aspects: see Facility Implementation Manual; Networking and Routing.

4. DATA FACILITIES

A data terminal connected to a line circuit (terminal connected via modem to ALC or terminal connected via SOPHO-SET, SOPHO-LAM or LAM to DLC) is regarded by the ISPBX as a normal extension. It does not distinguish between a data party and a voice party. ISPBX facilities are available for both types voice and data extensions. Some facilities however are not very useful for data parties.

In this chapter the facilities that are useful for data parties are discussed in more detail.

For a number of facilities the DNR of the extension must have a facility class mark assigned to it. Often this facility class mark can be directly assigned with the OM-command ASFACM or erased with the command ERFACM.

In some cases a special command must be used to assign or erase a facility class mark. These facility class marks are called Read-Only facility class marks as they are not assigned or erased with ASFACM or ERFACM. The correct OM-commands that must be used to assign the read-only facility class marks to a DNR are mentioned in the applicable facility description.

With the OM-command DIFACM all facility class marks that are assigned to a DNR can be displayed.

In a number of cases the extension user has to activate a facility by dialling a certain prefix from the extension (data terminal). In the facility description, the OM-command that must be used to assign the prefix in the correct analysis tree is mentioned. In this description a general knowledge of the ISPBX number analysis (analysis trees, analysis groups etc.) is assumed. For more information: see Facility Implementation Manual; Management.

With the OM-command MAKENU a prefix can be erased from an analysis tree. With the OM-command DINASD the number assigned in an analysis tree can be displayed.

4.1. ABBREVIATED DIALLING

The abbreviated dialling facilities offered for voice calls are also available for data calls, see Facility Implementation Manual, Voice Facilities.

4.2. AUTOMATIC ANSWER

A data terminal adaptor (SOPHO-SET, SOPHO-LAM or LAM) can be set to automatic answering. This is particularly useful for an unmanned data terminal or a data terminal with limited user control (such as a printer). This automatic answering option can be programmed

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locally either via the keypad, in the case of the SOPHO-SET or SOPHO-LAM or interactively from the keyboard of the data terminal.

It is also possible to program the option from the ISPBX. As the automatic answering option is part of the V.24 parameter in the CV, this option can be set in the compatibility value and downloaded to the data port of the SOPHO-SET, SOPHO-LAM or LAM.

4.3. CALL FORWARDING

The call forwarding facilities offered for voice calls are also available for data calls, see Facility Implementation Manual, Voice Facilities.

4.4. CALL WAITING INDICATION

The call waiting facility is available for both voice and data calls, see Facility Implementation Manual, Voice Facilities.

Note: A data terminal user cannot hear the call waiting tone burst and even the receipt of such a tone burst by a data terminal can disturb the synchronisation of the connection. The tone will not be sent to a busy terminal when the call of the busy DNR is data protected. A call can be data protected in 3 different ways as discussed in the `data protected' facility.Not only the call waiting tone burst is not sent towards the data terminal, it is even not possible to break in or listen in on the connection by either operator or other extension users.When FCM 35 (call waiting protected) is assigned to a DNR the call waiting tone burst is also not sent to the extension in case a call waiting is initiated for the busy extension. Break-in by the operator is still possible and if the operator dials the extension the tone burst is still sent.

4.5. CAMP ON BUSY

The camp on busy (COB) facility offered for voice calls is also available for data calls, see Facility Implementation Manual, Voice Facilities.

4.6. DATA GUARDING

This is a facility of the SOPHO-SET or LAM especially for data communication. The DCE (data port of SOPHO-SET or LAM) can be programmed to guard the connection for activity. If no

activity is detected over the transmit and/or receive lines within a certain, programmable time period, the SOPHO-SET or LAM sends a message to clear the call. This facility can be offered on outgoing and on incoming data calls.

4.7. DATA PROTECTION

A data connection between two data terminals uses synchronisation signals for the communication protocol. If a third party (for instance another extension, or an operator) is able to break-in on the connection, the synchronisation signals can be disturbed and the synchronisation between the data terminals is lost. Also a call waiting indication can have this effect. Therefore this interruption must prevented. This can be achieved in different ways:

- Both incoming and outgoing calls over a route are automatically data protected by setting the general route option `data protection applied' true.

- A DNR can be data protected by assigning FCM 04 (data protected) to the DNR. Every call made by or routed to the DNR is automatically data protected.

- A DNR can determine if the data protection must be applied. If the DNR is assigned FCM 05 (data protection entitled), the extension user can dial a prefix (initial or enquiry dialling) for dial up data protection. If this data protection is successful, the user receives dial tone and a normal call setup is possible. Only for this call the connection is data protected. After the call has been released the data protection mark is erased and must be set again for a next data protected call.

- If an IBSC is used that is not for speech then it is impossible for a speech oriented third party to break-in to the connection.

Note: The compatibility value with `data' indication is NOT used for making a call data protected. It is only used for the downloading of the interface parameters.

4.8. DOWNLOADING

Downloading is used for sending predefined settings from the ISPBX to a terminal. This downloaded data can be used to set the interface characteristics of a data terminal: either SOPHO SET or LAM.

Before the communication between the data port of the SOPHO-SET or the LAM and the data terminal can be correctly implemented, the interface between the two devices must be correctly programmed. This programming can be performed locally via the keypad of the SOPHO-SET or via the data terminal (interactively) connected via the interface. It is also possible to download the interface characteristics. In this case the settings of the interface are collected from the compatibility value that is assigned to the DNR of the data port.

Via the command CHAGCV the DNR of the data port can be assigned to a compatibility value.

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With the OM-command CRCVAL the compatibility can be defined as `data' and the interface parameters related to the compatibility value can be defined. Via the command CHCVAL the compatibility value and the interface parameters can be changed. The DNR of the data port of the SOPHO-SET or LAM is also assigned FCM 12 (SOPHO-SET) to indicate that the dial information is to be expected in a different way (no receiver keytone required) and the call progress information is to be sent towards the data port.

Note: The DNR of the data port is not related to a menu number: the function key data is only applicable for the voice port of the SOPHO-SET.

For more information, see Facility Implementation Manual, Voice Facilities.

4.9. FOLLOW-ME

The follow-me facilities offered for voice calls are also available for data calls, see Facility Implementation Manual, Voice Facilities.

4.10. GROUP HUNTING

The group hunting facilities offered for voice calls are also available for data calls, see Group Arrangements in the Facility Implementation Manual, Voice Facilities.

This facility is particularly useful for a pool of host computer ports, terminals or printers. Each data port has its own DNR; these ports must be collected in a group arrangement.

When a call is routed to the group-DNR a cyclic or fixed hunting sequence is started to find a free member of the group. The type of hunting sequence depends on the group properties assigned to the group arrangement.

Note: If group members are printer ports, they can not be switched absent/present. This must be done by a supervisor outside the group.For data groups involving SOPHO-SETs and LAMs it is advisable to disable the group display function. This prevents information being sent to the SOPHO-SET or LAM concerning the status of other group members. This information can not be used by the SOPHO-SET or LAM and has been known to cause problems.

4.11. HOT LINE DIALLING

The hot line facility offered for voice calls is also available for data calls, see Facility Implementation Manual, Voice Facilities.

Note: As the hot line option is also part of the V.24 parameter in the CV, this option can be set in the compatibility value and downloaded to the data port of the SOPHO-SET, SOPHO-LAM or LAM.If CT 108 is used as call request, it is advised only to use the delayed hot line facility. If the hot line call set-up is not successful and CT 108 remains active the data port immediately tries to set-up a new hot line call. If there is no delay between the retries, the continuous re-initiation of the hot line facility will increase the loading of the CPU.

4.12. KEYBOARD DIALLING

The number of another data terminal can be dialled from the keyboard of a DTE. The data port interface must be programmed either by downloading data from the ISPBX to the data port or by programming the data port locally on the LAM or SOPHO-SET. Keyboard dialling is the default condition for a DTE which is connected to a LAM. If the DTE is connected to a SOPHO-SET S375D, however, the SOPHO-SET must be programmed to allow keyboard dialling (see the appropriate manuals and user guides).

4.13. MNEMONIC / NUMBER DIALLING

The number of another data terminal can be dialled from the keyboard of the DTE by entering a mnemonic or code number. In the directory of the LAM or SOPHO-SET the code is translated into the real required number. This number is sent to the ISPBX for call set-up.

The directory is a facility of the LAM or SOPHO-SET. The directory can be defined / changed via the DTE. For more information: see applicable LAM or SOPHO-SET user guide.

4.14. PASSWORD PORT PROTECTION

To protect unauthorised use of data ports (host computers), password port protection may be required, see Facility Implementation Manual, Voice Facilities.

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A . CONNECTIVITY

The ISPBX acts as an integrated services PBX: it is possible to establish a digital 64 kbps transparent connection between any two ports in the fully integrated network irrespective if the parties connected to the ports are compatible. The system does not observe what is actually transferred over the connection between the ports. It accepts data bytes from a port and delivers this data byte to another port without processing the byte. Such a byte might for instance be a digitised voice sample or a byte of computer data.

To prevent connections between incompatible parties, the system manager must define which ports are allowed to be connected together. A number of tools are available for this purpose; number analysis, traffic classes, compatibility values, facility class marks, IBSCs and BSPTs. For more information on the use of these management tools: see Facility Implementation Manual; Management.

A.1. DETERMINING CONNECTIVITY

For a successful data connection it is necessary that both parties involved are compatible. A number of checks are done by ISPBX to ensure this compatibility. This section describes a number of important factors in determining connectivity.

- Internal Basic Service Category (IBSC).Each DNR has an IBSC allocated to it. - A default IBSC is allocated using NEBOUND 025. All DNRs get this IBSC unless

otherwise specified.- The IBSC of a DNR can be changed using the OM command CHDNRS.

- Basic Service Profile Type (BSPT).Each DNR and route has a BSPT allocated to it. - A default BSPT is determined using the IBSC as a reference as follows:

- The BSPT of a DNR can be changed using the OM command CHDNRS.- A route or bundle can have more than one BSPT allocated to it.- A BSPT can be assigned to a route using the OM command ASBSPR. For each BSPT

the route characteristics can be filled in with the OM commands CHRTCG, CHRTCI and CHRTCO,

- A BSPT can be added assigned to a bundle using the OM command ASBSPB. For each

IBSC: BSPT:Data oriented: 0, 2, 5... 13, 15... 17 94 (data/possibly data)Voice oriented: 1, 14, 18 95 (voice/possibly voice)Unknown: 3, 4, 19 98 (any)

BSPT the bundle characteristics can be filled in with the OM commands CHBNDC,- The maximum number of BSPTs per route is determined by NEBOUND 235.

- Basic Service Profile (BSP) - A Basic Service Profile (BSP) is a set of user characteristics, identified by a DNR and a

Basic Service. The Basic Service is indicated by an IBSC and a Basic Service Profile Type. The combination of DNR and BSPT is called a Basic Service Profile Identifier (BSP-ID) and is used as a parameter in several OM-commands to identify a BSP.

- A BSP is assigned to an EHWA using the OM command CHDNRC.

- Compatibility Value (CV). - A default CV is allocated to DNRs using NEBOUND 008.- A default CV is allocated to a route using NEROUTE 211.- The CV of a DNR can be changed using the OM command CHAGCV.- The CV of a route can be changed using the OM command CHRTCG.- The maximum number of CVs in the network is determined by NEBOUND 032.- The CV for a data port can be used to download the parameters of a DCE. Such a CV

can be created using the OM command CRCVAL or changed using CHCVAL. Downloading is done using DOWNLD.

The connection allowance of CVs is specified using the OM command CHCVCA.

Connectivity is determined as follows:

1. The IBSC of the calling party is compared with the BSPT of the called party according to table A.1. DETERMINING CONNECTIVITY. If a match is found then the two parties may be connected, unless prevented by the CV connection allowance.

2. The CV connection allowance is checked. If the connection allowance is 3, then the connection is allowed. If the connection allowance is 2, then a modem is required in the connection.

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58

BSPT IBSC PRIORITY DESCRIPTION

0 0 1 64 kBit/s unrestricted

1 1 1 Speech

2 2 1 3.1 kHz audio

3 3 1 3.1 kHz audio non-ISDN *

4 4 1 7 kHz audio

5 5 1 Teletex

6 6 1 Telefax4

7 7 1 Mixed mode

8 8 1 Videotex

9 9 1 Slow scan television

10 10 1 Fernwirken

11 11 1 GrafikTelefon

12 12 1 Bildschirmtext

13 13 1 Bildtelefon Bild

14 14 1 SOPHO speech *

15 15 1 SOPHO modem data *

16 16 1 X.21

17 17 1 X.25

18 18 1 Bildtelefon Ton

19 19 1 64 kBit/s unrestricted non-ISDN *

20...93 User definable

2 Free for use (CRBSPT command)

94 0, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17, 19

2 Data / possibly data

95 1, 3, 4, 14, 18, 19

2 Voice / possibly voice

Table A-1 BSPT and IBSC Connection Allowance.

A.2. SERVICE INDICATOR TRANSLATIONS

Some types of routes use an External Service Indicator (ESI) to identify the type of user information being sent. The ESI is handled by ISPBX as follows:

- For an incoming call. The External Service Indicator (ESI) received over a route is translated into an Internal Service Indicator (ISI). The ISI consists of an Internal Service Identification Code (ISIC) and an Internal Basic Service Category (IBSC). The ISIC, if available, is passed transparently to the internal port. The IBSC is used for the determination of compatibility within ISPBX.

- For an outgoing call. Information passed over the route must be accompanied by an External Service Indicator (ESI). The Lower Layer Compatibility (LLC) from the user port (if applicable) is incorporated into the ISIC. The ISIC and IBSC are combined into the ISI which is translated to an ESI.

The list below shows the route type and the name used to identify the ESI.

96 0, 2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17

3 Data

97 1, 14, 18 3 Voice

98 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19

4 Any (Default)

99 All BSPTs

Note: On a route only one BSPT with priority 2 is allowed. *=Non ISDN

Route type External Service Indicator (ESI)- ISDN External Service Indicator (ESI)- DASS 2 Service Indicator Code (SIC)- DPNSS No. 1 Service Indicator Code (SIC)

BSPT IBSC PRIORITY DESCRIPTION

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60

A.3. CONNECTION ALLOWANCE BETWEEN CVs

A CV can be assigned to an internal port as follows:

- ALC or DLC-circuits: each circuit is assigned a DNR. This DNR is assigned a CV with the OM-command CHAGCV;

- ATU or DTU-circuits: each circuit is assigned as a trunk or tie line in a route. This route is assigned a CV with the OM-command CHRTCG.

The CV is used as a tool for determining which ports can be connected together. The CV connection allowance can be:

- Not possible (0). The ports may not be connected and are not compatible.- Not allowed (1). The ports may not be connected (even though they may be compatible).- Allowed with convertor (2). A modem must be used to connect the two ports.- Allowed (3). The ports can be connected together.

The OM-command CHCVCA is used for defining the connection allowance between CVs. The command defines the connection allowance between the calling party (CV-A) and the called party (CV-B). To allow a connection to be set-up in both directions the command must be used twice, the allowance from party X to party Y and the allowance from party Y to party X.

For example: the following CV connection allowances have been defined in a FIN:

- 1TR6 1TR6-Service Indicator (1TR6-SI)- VN2 VN2-Service Indicator (VN2-SI)

Figure A-1 CV Connection Allowance Table.

A.4. CONVERTORS (MODEMS)

• ISPBX Determines Convertor Type UsedISPBX determines which type of convertor (modem) must be inserted in the data path. The system manager must define the convertor types and which type must be used in a certain data call.Connection Allowance.The internal DTE has a CV assigned to its DNR. The involved route also has a CV assigned to it. If the connection between the internal DTE and the route is only allowed when a modem is used then the CV connection allowance 2 is used, `allowed with convertor'. ISPBX knows that a modem has to be switched into the connection (between the DLC and the ATU).Convertor Type.The convertor type is determined by a table corresponding to the CV connection allowances. This table is defined by the system manager with the OM-command ASCVCT. This is a table indicating which convertor type must be used when CV-A is to be connected with CV-B. If the connection is to be set-up in both directions then the command must be used twice, once for outgoing data calls and once for incoming data calls.For example: the CV-CV convertor type table is defined as follows:

30

0

3

1

2

2

0

3

0

4

Called party

Calling partyCV-A

Digits inside the array:0 = Not Possible1 = Not Allowed2 = Convertor Required3 = Allowed

CV-B

31 3 0 0 3

22 0 3 0 2

03 0 0 3 3

04 3 2 3 3

61

62

Figure A-2 CV-CV Convertor Type Table.

A trunk line has a CV of 4 and the internal DTE has a CV of 2. The CV connection allowance is 2, which indicates `allowed with convertor' for both incoming and outgoing data calls. Looking at the convertor type table gives convertor type 23, which will be included in the data path for both an incoming and for an outgoing call.

• User Determines Convertor Type UsedIf the CV connection allowance indicates that a modem is required either the ISPBX or the extension user can indicate what type of modem must be used.If the ISPBX makes that decision the second table as described above is used. With this mechanism however, a DTE can only access the same convertor type every time the extension makes the same outgoing data call (dialling the trunk access code and the external number).If the extension user wishes to select another modem type, for instance with another data speed, then the user can select which convertor type is switched into the data path. The user has to dial the `Convertor Prefix' and `Convertor Type Number' followed by the trunk access code for the required destination and the external number. ISPBX now selects a modem from the pool with the dialled convertor type number, overruling the CV-CV convertor type table. - The convertor prefix (with res. id. 68) must be assigned in the analysis tree of the

calling party.- The convertor type number is defined using the OM command CRCTYP.

0

0 1

15

2 3 4Called party

Calling partyCV-A

Digits inside the array represents therequired MODEM Pool Type (0...254)for the CV-CV Combination.

CV-B

1

152 23

3

4 23

Convertor dialling can also be used internally or from DDI (prefix+convertor type+internal DNR).

A.5. CV USED FOR PROGRAMMING THE DATA PORT

If the CV is assigned as data then it can be related to a number of parameters which can be downloaded to a SOPHO-SET, SOPHO-LAM or LAM. The parameters are used for programming the data port of the SOPHO-SET, SOPHO-LAM or LAM.

The SOPHO-SET, SOPHO-LAM or LAM is connected to a DLC port via a 2B+D line. Each DLC port comprises 2 circuits which correspond to the user channels in the 2B+D line.

- For a SOPHO-SET the second user channel (corresponding to an odd DLC-circuit) corresponds with the data port.

- For a SOPHO-LAM either user channel (corresponding to the even and odd DLC-circuit) corresponds with the data port.

- For a LAM both user channels (corresponding to both the even and odd DLC-circuits) correspond with the data port.

The DLC-circuit corresponding to a data port is assigned a DNR. A CV is assigned to the DNR as described above. This CV must be for data and subsequently have the additional interface parameters.

The parameters are downloaded to the data port in the following circumstances:

- Manual request with OM-command DOWNLD.- If the DLC-circuit is transferred to the service condition INS.- Whenever the SOPHO-SET, SOPHO-LAM or LAM is connected to the telephone line.- Upon manual request of the user.- If the OM-command CHAGCV is used.

Downloading involves sending the parameters of the CV to the SOPHO-SET, SOPHO-LAM or LAM using the 2B+D protocol. The SOPHO-SET, SOPHO-LAM or LAM interprets the values and programs the setting of the data port accordingly.

The CV is created or changed using the OM-command CRCVAL or CHCVAL. It is assigned as either data (D) or voice (V). If the CV is assigned as data then the additional parameters can be defined. These additional parameters are separated into 4 groups: <V.24-circuits>, <speed+mode>, <miscellaneous>, <guard 1 + guard 2>.

The parameters and their ranges for the SOPHO-SET 308, SOPHO-SET S375 D, SOPHO-SET P375 D, SOPHO-SET P370 D, SOPHO-LAM P375 and LAM 308 are not all the same.

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Refer to the Customer Engineer Manual, User Guide or Data Guide for the set required.

The parameters and their ranges for the LAM 309 are given below.

A.5.1. LAM 309

The X.21 interface parameters for the data port of the LAM 309 are programmed in the same way as the V.24 interface parameters. In the applicable fields of the expanded CV for data, some parameters are treated differently as described for the V.24 interface. Refer to the Customer Engineer Manual for further details.

• V.24-CircuitsThe parameter field `V.24-Circuits' in the CV is a string of 12 parameters which can individually be set to yes (1) or to no (0). Out of this string only parameter A is used. - A. AUTO CLEAR.

This parameter is only used if the LAM 309 is programmed for leased line configuration (see miscellaneous parameters).• If set to 0, the LAM 309 will set-up and clear the hot line connection depending on the state of the data terminal connected to the port. When the X.21 DTE is ready the LAM 309 will send a message towards the ISPBXto set-up the hot line connection. When the X.21 DTE is not ready the LAM 309 will send a message towards the ISPBX to clear the hot line connection.• If set to 1, the hot line call set-up and clear request is done using the key on the front of the LAM 309.

• Speed+Mode

• MiscellaneousThe parameter field `Miscellaneous' is a string of 12 parameters which can individually be set to yes (1) or to no (0) or to a certain value. Out of this string only parameters B, D, E, F and G are used. Unused parameters should be set to 0. - B. SUBADDRESSING.

Set this parameter to 0.

This parameter is 2 or 3 digits. The first 1 or 2 digits indicates the terminal speed:7 = 600 Baud 17 = 19200 Baud8 = 1200 Baud 18 = 38000 Baud10 = 2400 Baud 19 = 48000 Baud12 = 4800 Baud 20 = 56000 Baud14 = 9600 Baud 21 = 64000 BaudThe last digit indicates the conversation mode1 = Full duplex, synchronous 5 = Simplex outgoing, synchronous3 = Half duplex, synchronous 7 = Simplex incoming, synchronous

- D. DIRECT CALL.This parameter defines if the call set-up must be performed via a hot line relation (leased line) or via the entry of dial information by the user.• If this option is set to YES, the hot line relation is used. The data port sends a call set-up request towards the ISPBX as soon as the X.21 data terminal becomes active or the terminal user presses the key on the LAM 309 (depending on the `V.24'-parameter Auto Clear).In the ISPBX a hot line must be defined between the originating DNR (LAM 309 data port) and the destination DNR. When the ISPBX receives the call set-up message the hot line facility is activated and the connection is established.To release the hot line connection the data port sends a clear message. This message will be sent when the X.21 data terminal switches inactive or when the terminal user presses the key on the LAM 309 (depending on the `V.24'-parameter Auto Clear).• If this option is set to NO, the data port waits for further dial information before it sends a call set-up request. The ISPBX uses the dial information for determining the call establishment between an originating DNR and a destination DNR. The destination number may be stored in the LAM 309 (see chapter Internal Data Communication).

- E. BYTE ORIENTED PROTOCOL.This parameter defines if the transfer of information between the data terminal and the data port is byte or bit oriented.• If this parameter is set to 0, the protocol is bit oriented. In this case the value for parameter 6 (wordlength) is not important. The subsequent bits do not represent a byte. The bits are just placed one after the other and this way the digital information is transferred to the destination party.• If this parameter is set to 1, the protocol is byte oriented. The number of bits in a byte is determined in the next parameter (wordlength).

- F. WORD LENGTH (5, 6, 7 or 8 bits).This parameter defines the length of the actual data word.Set this parameter to 7.

- G. PARITY (no, even or odd parity).This parameter defines if a parity bit is sent after the data word.Set this parameter to 2, (odd parity)

• Guard 1 + Guard 2This parameter consists of exactly 6 digits, MMMSSS, and can be divided into two parts: - MMM for GUARD 1, the dataguarding time in minutes, (000...255).

If there is no activity on both the receive and transmit lines for a certain time period, the call is cleared autonomously by the data port of the LAM 309. The applicable time period is defined here.

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Note: If the timer is assigned the value 000, the timer is not used any more. The data guarding is NOT active.

- SSS for GUARD 2. Not used for a LAM 309. Enter 000.

B . MODEM LINE UNIT

A modem line unit (MLU) is a board that is used to make it possible to use a modem as a common pool resource. This board controls a maximum of 4 modems. The communication between the MLU and the modem can be synchronous or asynchronous.

For each modem the MLU has two ports: one port with the V.24 interface to the modem and one port with the analogue (2 or 4 wire) interface to the same modem. Both ports are available at F122 front connectors:

Table B-1 Front connector positions on MLU.

In the Hardware Manual and in the Installation Manual the layout of the front connector for the V.24 interface is illustrated.

The analogue line to the modem can be 2-wire or 4-wire and this type must be set accordingly by means of straps on the MLU. The straps are numbered X1.1 to X1.8:

- X1.1 and X1.2 for modem number 0;- X1.3 and X1.4 for modem number 1;- X1.5 and X1.6 for modem number 2;- X1.7 and X1.8 for modem number 3.

The board positions of the straps and the correct settings for 2-wire or 4-wire operation are given in the Maintenance Manual.

To be able to adapt the receive level of the input signal on the analogue line of a modem, the PAD belonging to this line can be set to one of three levels: -25 dBr, -28 dBr or -31 dBr. By means of one strap the detection level can be determined per modem. The straps are numbered X2.1 to X2.4:

- X2.1 for the detection level for modem number 0;- X2.2 for the detection level for modem number 1;

MODEM V.24 PORT AT ANALOGUE LINE AT

NUMBER CONNECTOR CONNECTOR

0 FBA FCA

1 FBB FCB

2 FBC FCC

3 FBD FCD

67

68

- X2.3 for the detection level for modem number 2;- X2.4 for the detection level for modem number 3.

The board positions of the straps and the correct settings for the detection levels are given in the Maintenance Manual.

A schematic overview of the MLU is given in figure Figure B-1 Schematic Overview of MLU circuit with connected Modem., with one modem connected. For the V.24 interface the modem acts as the DCE and the MLU as the DTE. The control of the board is performed by a microprocessor. This control is common for all modem-circuits. This control guards the status of the 4 modem-circuits on the board. The status changes of the modems are transferred to the PPU and further on to the CPU via the CODI and CODO 2 Mbps lines, on the back panel. The user information is transferred via the USI and USO 2 Mbps lines to the PSC/PMC and further on to the switching network., The card uses the clock signal from the back panel for timing purposes, to be able to access the correct position (timeslot) in the 2 Mbps lines USO/USI.

Figure B-1 Schematic Overview of MLU circuit with connected Modem.

The most important V.24 signals in the interface between the modem and the MLU affect the operation of the modem as illustrated in figure Figure B-2 Schematic Overview of Modem connected to MLU.

Dill Switches

2 Straps 1 Strap

CODO

CODEC

CODI

D

A

V.24DRIVER

V.24

Analoguefrom

modulator / to

demodulator

MODEM MLU

INPUTPORT

TIMING

µP CONTROL

CLOCKADAPT

DATARATE

ADAPTOR

OUTPUTPORT

103105113

107

142

104106115109

108.1111126140141102

TxDRTSTSET

DSR

T1

USO

USI

CLOCK

CDSLDSRSSTFRILLLGND

V.25 TONE GENERATOR1300 Hz CALLING TONE2100 Hz or 2225 HzANSWERING TONE

V.25 TONE DETECTOR2100 Hz or 2225 HzANSWERING TONE

V.24RECEIVER

RxDRFSRSETDCD

abcd

2 / 4SELECT

PAD

69

70

Figure B-2 Schematic Overview of Modem connected to MLU.

The V.24 signals mentioned are explained in more detail below.

- CT103 (TXD) transmitted data:Digital information that is to be modulated and transmitted.

MODEM MLUDATA/VOICECONTROL

RTS

RFS

TSET

RSET

DCD

RI

RILTILL

TXD

DSRS

STF

RxD

DSR

CDSL

CT105

CT106

CT113 *)

CT115 *)

CT109

CT125

CT140CT142CT141

CT103

CT111

CT126

CT104

CT107

CT108.1

TRANS/RECCONTROL

TRANSMITCLOCK

*) Only used with synchronous communication.

SHIFTREGISTER

SHIFTREGISTER

MOD

DEMOD

RECEIVECLOCK

CARRIERDETECT

RINGINDICATOR

TESTCONTROL

- CT104 (RXD) received data:Digital information that is received and demodulated.

- CT105 (RTS) request to send:The MLU wants to send digital information and initiates a request towards the modem.

- CT106 (RFS) ready for sending:If the MLU initiated a send request and the modem is able to send the digital information, the ready for sending signal indicates to the MLU that the information can be transmitted.

- CT107 (DSR) data set ready:This signal indicates that the analogue line is switched from the telephone to the modem.

- CT108.1 (CDSL) connect data set to lineThe command from the MLU towards the modem to switch the analogue line from the telephone set to the modem.It is not possible to use the CT108.2 (DTR) signal. This signal is just an indication to the modem the MLU is ready for operation. By means of a second condition (manual switch over or ring indicator) the modem switches the telephone line from the telephone to the data port. Because the ring indicator signal (CT125) is not supported by the MLU and because the modem must operate in the unattended mode this second condition cannot be fulfilled. CT108.1 (CDSL) must be used: this signal is a real command which does not need a second condition.

- CT109 (DCD) data carrier detect:This signal indicates to the MLU that an incoming carrier signal is detected.

- CT111 (DSRS) data signal rate selection:If the modem offers the possibility to operate with a high or a low speed, the MLU is able to select the high or the low speed by means of this signal. The lower speed can be selected if there are too many transmission errors detected.If this signal is true the high transmission speed is selected in the modem.If this signal is false the low transmission speed is selected in the modem.

- CT113 (TSET) transmit signal element timing:Only used in synchronous transmission. The MLU provides the transmit clock for the modem.

- CT115 (RSET) receive signal element timing:Only used in synchronous transmission. The modem sends the clock signal retrieved from the incoming data stream to the MLU.

- CT126 (STF) select transmit frequency:For an incoming call the modem receives data in the low frequency band (forward channel) and sends in the high band (backward channel).For an outgoing call the modem sends in the low frequency band (forward channel) and receives in the high band (backward channel).By means of this signal the MLU can determine if the modem sends in the low or in the high band.If this signal is true the high frequency band is selected for transmitting data (answering

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mode).If this signal is false the low frequency band is selected for transmitting data (calling mode).This signal must be available if the modem is used both for incoming and for outgoing calls. If the modem does not support this signal, the modem pool must be assigned a call direction: incoming calls only or outgoing calls only.If a modem does not support this signal, the MLU cannot tell the modem in what frequency band to transmit and to receive. The modem cannot be used in bothway operations, it must be used in one direction only: incoming or outgoing and the modem must be strapped accordingly.The centre frequency in the channels are 1200 Hz for the low channel and 2400 Hz for the high channel.

- CT140 (RIL) remote interface loop:The MLU can send a request to the opposite modem to force a remote loop back for test purposes.

- CT141 (LL) local loop:The MLU can send a request to the local modem to force a local loop back for test purposes. Only if the modem is able to connect CT103 and CT104 can the test mode be entered;

- CT142 (TI) test indicator:The modem indicates to the MLU that the test mode is entered after a loop request.

Note: The MLU does not support the RI - ring indicator signal (CT125).

B.1. V.25 CALLING AND ANSWERING TONES

If a modem is equipped with an Automatic Calling Unit, the connected DTE can send a destination number to this ACU. The modem now transfers the digits to the network. When the opposite modem answers the call, calling and/or answering tones can be used for the synchronisation between the modems and for echo suppression in the network. The DTE can communicate with the modem by means of the V.25 commands and indications. With V.25 the CT200-series signals are available for this communication. With V.25 bis the communication is performed via the normal RXD and TXD (CT103 and CT104) lines.

In this part we are not interested in this DTE-DCE communication but what happens on the line: the calling and answering tones. The calling tone is repetition of a tone burst of 1300 Hz during 0.5 - 0.7 sec. followed by silence for 1.5 - 2.0 sec. The answering tone is a continuous tone of 2100 Hz during a maximum of 3.3 - 4.0 sec.

The transparent connection is established.

The procedure on the line is illustrated in figure Figure B-3 V.25 (bis) Calling and Answering Tones.

If the calling and answering tones are not used, the calling modem regards the received 2400 Hz carrier as the answering signal and starts sending the forward 1200 Hz carrier.

Calling party: When the calling party has fully dialled the number of the destination party, the network control establishes the call through the network and sends ring current to the called party.

Called party: The receiving modem detects the ring current and sends the signal ring indicator (CT125) to the DTE. The DTE switches the modem on line via CT108.

Calling party: The calling modem detects that the called party is off-hook and starts sending calling tone.

Called party: The called modem detects the calling tone and sends back the answering tone.

Calling party: When the calling modem detects the answering tone, it stops sending the calling tone.

Called party: The called modem detects the end of the calling tone and stops the answering tone. Now also the signal CT107 is returned to the DTE to indicate the modem is ready for operation. The DTE sends CT105 to the modem and the modem starts sending the carrier in the backward channel.

Calling party: When the calling modem detects the end of the answering tone, it returns CT107 to the DTE to indicate the modem is ready for operation. At the same time the carrier in the backward channel is received and CT109 indicates that the called party is present.The DTE sends CT105 to the modem and the modem starts sending the carrier in the forward channel. CT106 indicates that the called party is on-line and the DTE may start sending information.

Called party: When the called modem detects the carrier in the forward channel CT109 indicates that the calling party is on-line. CT106 indicates that the DTE may start sending information.

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Figure B-3 V.25 (bis) Calling and Answering Tones.

Note: If the calling modem does not provide the generation of the V.25 calling tone and/or the detection of the V.25 answering tone, the called party will send the answering tone for the maximum defined duration of 3.3 sec. followed by the carrier in the high band. The calling party will not respond to the answering tone but will detect the 2400 Hz carrier and consider it to be the indication that the called party is connected. After sending the 1200 Hz carrier the connection is established.

If the called modem does not provide the detection of the V.25 calling tone and/or the generation of the V.25 answering tone, the called party will not respond to the calling tone and immediately send the carrier in the high band. The calling modem will detect this 2400 Hz carrier and consider it to be the indication that the called party is connected. After sending the 1200 Hz carrier the connection is established. If neither the called modem nor the calling

V.24 +V.25 (bis)

V.24 +V.25 (bis)

MODEMNETWORKMODEM

Calling DTE Called DTECT108 on (CDSL)Off-hookDial toneTransfer dial informationEnd-of-dialling

Detect off hook

Send calling home

Detect answering tone

Stop calling tone

Detect end answering tone

CT107 on (DSR)

Data transfer phase

CT105 on (RTS)

CT109 on (DCD)

CT106 on (RFS)

CT107 on (DSR)

Data transfer phase

CT105 on (RTS)

CT106 on (RFS)

CT109 on (DCD)

Carrier 2400 Hz

Call establishment

Carrier 1200 Hz

Off hook

Detect calling tone

Send answering tone

Detect end calling tone

Stop answering tone

CT125 on (ring indicator)CT108 on (CDSL)

modem provide the generation/detection of the V.25 calling tone or the generation / detection of the V.25 answering tone, the called party will immediately send the carrier in the high band. The calling modem will detect this 2400 Hz carrier and consider it to be the indication that the called party is connected. After sending the 1200 Hz carrier the connection is established.

B.2. MODEM USED AS CONVERTOR IN POOL

If an analogue trunk line can be used for both voice and data calls, it is necessary to switch a modem into the connection for data calls. Such a modem can be located in a modem pool both for incoming and for outgoing calls. Only when such a trunk line is used for a data connection, is the modem to be used.

The modem is connected to the MLU by both the V.24 interface and the analogue line.

Note: The projecting signalling group for the MLU always indicates that the modem can be used for outgoing calls and for incoming calls. The MLU uses CT126 (STF) to set the modem in the answering or calling mode. If the modem does not support CT126, it must be strapped for one direction only. By means of the relation CV-A-CV-B-modem pool type, the modem must be assigned to a pool with modems with one direction: incoming or outgoing. The relation CV-trunk line-CV internal party (incoming) now uses a different modem pool type than for the relation CV-internal party-CV-trunk line (outgoing).

B.2.1. Incoming Call

Modem pool dialling with incoming calls is only possible for trunk lines which support Direct Dial In (DDI). If DDI is not possible, the call is routed to the operator or a Permanent Line Extension and modem pool dialling is not used. A call to a PLE can be routed to a modem which is determined by the CV matrix (route CV/PLE CV).

If a modem in the modem-pool is idle, all signals between the MLU and the modem are in the off-condition.

Call processing detects an incoming call over an analogue trunk line (with CV) via the line signals. The ISPBX retrieves the required destination number by the register signalling.

This number indicates a destination party to which a compatibility value is assigned. The compatibility check between the trunk-CV and the destination-CV is used to find out whether the party is a data party and which type of modem must be used for the connection. Now a free circuit on a MLU with the correct modem type is seized.

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Two data paths are established through the switching network:

- From the ATU circuit to the MLU:The analogue input signal from the trunk line is digitised (A/D convertor) on the ATU board into a standard 64 kbps signal. This digitised analogue signal is sent to the MLU, via the switching network, in the USO-line. The analogue signal is retrieved from the USO line and sent to the modem.

- From the MLU to the destination party:After demodulation the resulting user information is sent back in V.24 format to the MLU. The V.24 user information is transferred to the internal party, via the data rate adaptor, in 64 kbps format in a timeslot in the USI-line. The user information is retrieved and transferred to the SOPHO-SET, SOPHO-LAM or LAM, via the related DLC circuit, in a 64 kbps signal. Here the V.24 user information is retrieved from the 64 kbps signal and sent to the data party.

For full duplex data communication, the reversed path must also be established through the switching network.

Call processing sends ringing current to the destination party and starts waiting for the answering of the call. The call establishment is guarded by timers.

When the destination party answers the call, manually or automatically, the pool-modem is activated:

- CT108.1 (CDSL) forces the modem on-line.- CT111 (DSRS) is sent to the modem to indicate if the high or the low speed must be used-

depending on the projecting of the MLU-circuit.- CT126 (STF) is set in the on-situation to indicate the modem must send in the high-

frequency band and receive in the low-frequency band (answering mode).- The modem returns the signal CT107 (DSR) to the MLU circuit to indicate that the

modem is ready for operation.- If the V.25 tone sequence is used, either the modem or the MLU circuit sends answering

tone for 3.3 sec. If the V.25 tone sequence is not used, this step is skipped.- The MLU circuit forces CT105 to on and the modem starts sending the 2400 Hz carrier

(answering mode).- If the modem receives the 1200 Hz carrier from the remote modem, CT109 (DCD) goes

on to indicate that the DTE must be ready to accept data. The signal CT106 (RFS) from the modem indicates that the opposite party is on-line and that the DTE may start sending information.

The connection between the remote party and the local party is established.

Note: Depending on the projecting of the MLU it can switch the CT111 circuit (DSRS) to off or on to indicate to the modem that the low or the high speed must be used. For more information: see projecting aspects.

B.2.2. Outgoing Call

Modem pool dialling with outgoing calls is usually only applied on trunk lines which support DDO.

If a modem in the modem-pool is idle, all signals between the MLU and the modem are in the off-condition.

If a party (internal) initiates a call request to a destination (trunk access code to a destination via an analogue trunk line with CV), the compatibility check is used to find out that a modem of a specific type must be used for that trunk line. Now a free circuit on a MLU with the correct modem type is seized.

For an outgoing call, first the dial information is transferred over the trunk line in the applicable signalling type (bundle dependent!). The V.25 Automatic Calling Unit of the modem is not used.

Two data paths are established through the switching network:

- From the destination party to the MLU:The V.24 user data is incorporated in a 2B+D 64 kbps signal by a SOPHO-SET, SOPHO-LAM or LAM and transferred to the MLU circuit via the DLC-circuit and the switching network. The V.24 user data is retrieved from the 64 kbps signal and sent to the modem.

- From the MLU to the ATU circuit:After modulation the analogue modem signal is digitised and sent in a 64 kbps signal to the ATU circuit. Here the modulated user information is reconstructed back to analogue and sent over the trunk line.


Now call processing starts waiting for the call to be answered. The call establishment is guarded by timers.

When the call is answered by the destination party, the pool-modem is activated:

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- CT108.1 (CDSL) forces the modem on-line;- CT111 (DSRS) is sent to the modem to indicate if the high or the low speed must be used-

depending on the projecting of the MLU-circuit;- CT126 (STF) is set in the off-condition to indicate the modem must send in the low-

frequency band and receive in the high-frequency band (calling mode);- The modem returns the signal CT107 (DSR) to the MLU circuit to indicate the modem is

ready for operation;- If the V.25 tone sequence is used, either the modem or the MLU circuit sends calling tone

and starts waiting for the answer tone. If the answering tone is detected by the modem or the MLU circuit, the calling tone is stopped. If the V.25 tone sequence is not used, this step is skipped;

- The MLU circuit forces circuit CT105 (RTS) to on;- The modem starts waiting for the backward 2400 Hz carrier. If this carrier is detected the

modem knows the opposite party is on-line. The circuit CT109 (DCD) indicates to the DTE (MLU) that the DTE must also be ready to accept data. The modem now starts transmitting the 1200 Hz carrier in the forward channel and returns CT106 (RFS) to the DTE to indicate the DTE may starts sending.


Note: Depending on the projecting of the MLU it can switch the CT111 circuit (DSRS) to off or on to indicate to the modem that the low or the high speed must be used. For more information: see projecting aspects.

B.3. MODEM USED FOR LEASED LINES IN POOL

A modem can also be used in a pool when leased lines to a fixed data party (with a modem) are available. In this configuration it is not possible to send or receive dial information to or from the opposite party.

The analogue trunk line is only used for data connections, so they can have a fixed modem assigned to them. Only the connection between the related internal data party and a free modem must be established. The analogue interface of the modem is not connected to the MLU but directly to the leased line.

As the tone generators and detectors of the MLU are related to the analogue interface, the MLU cannot offer the V.25 calling and answering tone functions to the modem.

B.3.1. Outgoing Call

For an outgoing call over a leased line, the procedure is the same as the seizure of a free trunk line when making an outgoing -voice- call. Therefore the MLU-circuits with the modems connected, are assigned a line number and related to a bundle, route and destination. When an internal data party wants to have access to the external data party, only the trunk access code to the destination is enough (CV connection allowance: allowed) to seize a free line (including modem) to the external data party.

If the modem is idle, the MLU circuit still forces the modem on-line using CT108.1. The modem returns the signal CT107 to indicate that the modem is ready for operation.

Guarding of the line:

In some cases the remote data party offers a constant carrier on the line. In this case the signal CT109 from the modem indicates that the carrier is being received. If this carrier is not present, it may indicate a problem with the line and the MLU circuit is set into the ABL-FAIL condition. The guarding of the line can be enabled or disabled in the projecting data. For more information: see Projecting aspects.

If the send and receive frequency of the modem is controlled by the MLU by signal CT126 (STF), the constant carrier can only be in the high frequency band. If the modem is idle the signal CT126 is in the off-condition. The modem is set in the calling mode and only detects the carrier in the high-frequency band.

If the send and receive frequency is controlled by the modem itself (switchess and/or straps) the constant carrier can be in the high (modem in calling mode) or in the low (modem in answering mode) channel.

If a party initiates a call request to a destination (trunk access code), the compatibility check allows the connection. Now a free circuit on a MLU in the correct route is seized.

One data path is established through the switching network:

- From the calling party to the MLU:The V.24 user data is incorporated in a 2B+D 64 kbps signal by a SOPHO-SET, SOPHO-LAM or LAM and transferred to the MLU circuit via the DLC-circuit and the switching network. The V.24 user data is retrieved from the 64 kbps signal and sent to the modem.


The outgoing route option `direct switch through' must be yes. As no answer signal can be

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received over this ̀ trunk line' (not an ATU-circuit), call processing does not wait for an answer signal from the `trunk line' but immediately establishes the transparent connection between the remote and the local modem. The rest of the connection set-up must be performed by the MLU and the modem:

- CT111 (DSRS) is sent to the modem to indicate if the high or the low speed must be used-depending on the projecting of the MLU circuit;

- CT126 (STF) is sent to the modem to indicate if the modem must receive in the high frequency band and send in the low frequency band (calling mode) or receive in the low frequency band and send in the high frequency band (answering mode)-depending on the projecting of the MLU circuit;

- The MLU circuit forces circuit CT105 (RTS) to on;- The modem starts waiting for the carrier from the remote party. If this carrier is detected

the modem knows the opposite party is on-line. The circuit CT109 (DCD) indicates to the DTE that the DTE must be ready to accept data. Now the modem starts transmitting the carrier in the opposite channel. The modem returns CT106 (RFS) to the DTE to indicate the DTE may start transmitting data.


B.3.2. Incoming Call

For an incoming call over a leased line, the procedure is quite different from the convertor situation. Because there is no way of detecting an incoming call when the line is connected to the telephone set (unattended modem), the CDSL (CT108.1) signal must be continuously active. The modem is continuously connected to the telephone line. The CT107 signal (DSR) is returned to the MLU to indicate the modem is connected to the telephone line.

An incoming seizure on the MLU circuit is only possible if the circuit is projected for NO constant carrier-see Projecting Aspects.

If the pool-modem is idle and detects an incoming carrier, the signal DCD (CT109) to the MLU is activated and the MLU circuit sends a message to the SOPHO-S2500 CPU to indicate an incoming seizure.

If the send and receive frequency of the modem is controlled by the MLU by signal CT126 (STF), the incoming carrier can only be in the high frequency band. If the modem is idle the signal CT126 is in the off-condition. The modem is in the calling mode and detects only the carrier in the high-frequency band.

If the send and receive frequency is controlled by the modem itself (switches and/or straps) the incoming carrier can be in the high (modem in calling mode) or in the low (modem in

answering mode) channel.

After the incoming seizure the pool-modem is inserted into the call processing state. Over a leased line NO dialling information can be received by the modem and call processing does not receive any indialling information: the leased line behaves like a trunk line without DDI. Normally the call will be routed to an operator A-queue (incoming route option) but with digital information this will not be very useful. Another option is to assign a Permanent Line Extension (digital party) to the `trunk' lines in this route. This PLE-data terminal (can also be a group of terminals) answers the incoming calls over the leased line.

DDI with digit conversion to a complete number can also be used.

One data path is established through the switching network:

- From the MLU to the PLE:The analogue (modulated) signal now enters directly on the modem. The demodulated user information is sent in V.24 format to the MLU and the data rate adaptor incorporates the user information in the 64 kbps standard signal. The 64 kbps signal arrives at the SOPHO-SET, SOPHO-LAM or LAM (via the switching network and the DLC circuit). This device retrieves the user information from the 64 kbps signal and sends it to the data terminal.


The outgoing route option `direct switch through' must be yes.

As the analogue part of the MLU is not used the tone generation and detection circuits of the MLU are not available: the modem must be able to generate and detect the necessary tones.

When the call is answered by the destination party (PLE), the pool-modem is activated:

- CT111 (DSRS) is sent to the modem to indicate if the high or the low speed must be used-depending on the projecting of the MLU-circuit;

- CT126 (STF) is sent to the modem to indicate if the modem must receive in the high frequency band and send in the low frequency band (calling mode) or receive in the low frequency band and send in the high frequency band (answering mode)-depending on the projecting of the MLU circuit;

- The MLU circuit forces circuit CT105 (RTS) to on;- The modem starts waiting for the carrier from the remote party. If this carrier is detected

the modem knows the opposite party is on-line. The circuit CT109 (DCD) indicates to the DTE that the DTE must be ready to accept data. Now the modem starts transmitting the carrier in the opposite channel. The modem returns CT106 (RFS) to the DTE to indicate

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the DTE may start transmitting data.


B.4. DIL-SWITCH SETTINGS

The mode of operation of each modem can be specified using 2 groups of 8 DIL-switches (only switches 1 to 12 are used; switches 13 to 16 are not used).

Table B-2 Communication Speed for Modem.

- Switch 8: select synchronous or asynchronous communication.S8 off: asynchronous communication.

If the communication is asynchronous the speed of the communication is determined by the projecting of the MLU and the speed of the user terminal for the initiated call.

S8 on: synchronous communication.If the communication is synchronous the speed of the communication must be set with the DIL-switches 1 to 5: see table B.2.

SPEED S1 S2 S3 S4 S5

600 on off off off on

1200 off on off off on

2400 on on off off on

4800 on off on off on

9600 on on on off on

19200 on on off on on

38400 off off on on on

48000 on off on on on

56000 off on on on on

64000 on on on on on

Table B-3 V.25 tone generation options.

- Switch 7: select the convertor or the leased line mode of the MLU-circuit.This switch must be set the same for all circuits on the MLU: all modems on the MLU are used as leased line or as convertor. Mixed modem-use on one MLU (convertor and leased line) is not possible.

S7 off: modem used as convertor configuration.S7 on: modem used in leased line configuration.

If the modem is used in the convertor configuration (see switch 7) the following switches are used to determine the call control procedure:- Switch 11: select if CT106 or CT109 must be used as answer signal.

S11 off: CT106 or CT109 are not used as answer signals.S11 on: CT106 or CT109 are used as answer signals.

- Switches 9 and 10: select if modem or MLU generates the V.25 answer and calling tones.S10 off: modem generates the answering tone itself; switch 9 determines if

the MLU or the modem generates the calling tone.S9 off: modem also generates the calling tone itself; the MLU does not have

to generate any tone.S9 on: modem does not generate the calling tone; the MLU must generate

calling tone.S10 on: modem does not generate any tone itself; the MLU must generate

answering tone and calling tone; S9 must be on !

S9 S10 MEANING

off off modem generates calling and answering tones

no tone generation by MLU

on off modem generates answering tone but does not generate calling tone

calling tone generation by MLU

off on not valid

on on no tone generation by modem

MLU generates calling and answering tones

- Switch 6: select which frequency is used as answering tone.S6 off: MLU sends answering tone 2100 Hz.S6 on: MLU sends answering tone 2225 Hz.

- Switch 12: select the normal or the delayed CT108 operation.

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The board positions of the DIL switches and a flow diagram for the settings is given in the Maintenance Manual.

B.5. PROJECTING ASPECTS

Each modem-circuit on the MLU is projected with the signalling group 16XX. In the subsignalling group (XX) 7 bits (bits 0 to 6) are used to define the operation of the related modem and 1 byte (byte 0) is used to define the highest possible communication speed for that modem.

With some modem types the activation of CT108 will initiate a protocol between the DTE and the modem for dial information. In the modem pool use this is not useful. Therefore a delayed CT108 operation is introduced. When a modem out of a pool is to be inserted in the connection, first V.25 answer tone is sent to the modem and after a time period CT108 is activated. The modem detects the answer tone and the protocol is not initiated any more.

S12 off: normal CT108 operation.S12 on: delayed CT108 operation.

Bit 0 (leased line connection): This bit indicates if the modem is used for a leased line connection. 0 The modem is used as V.24 / analogue convertor and two paths through the switching

network must be established: from the DLC-circuit to the V.24 interface of the MLU circuit and from the analogue interface of the MLU circuit to the ATU-circuit. The MLU circuit must be assigned to a modem pool. In this case the board must be assigned with board type 33.

1 The modem is used for leased line connection and only one path through the switching network has to be established: from the DLC-circuit to the V.24 interface of the MLU circuit (the analogue interface of the MLU circuit is not used). The MLU circuit with the modem and leased line is regarded a normal trunk line by the SOPHO-S. In this case the board must be assigned with board type 22. A free MLU-circuit can be seized using a normal trunk access code to a destination with a leased line connected via a modem.

Bit 1 (constant carrier): only used with leased linesThis bit indicates if the modem expects a constant carrier on the leased line.0 The MLU regards a carrier signal on the line (indicated by the DCD signal from the

modem) as an incoming seizure of the leased line. Because the modem cannot receive any dial information from the trunk line `DDI' is not possible. The trunk line must be related to a -digital- PLE where the incoming call is directed to.

1 The MLU does not regard a carrier signal on the line (indicated by the DCD signal from the modem) as an incoming seizure.

Bit 2 (speed switching call dependent): only used when modem used as convertorThis bit indicates if the transmission speed of the modem can be switched between high-speed and low-speed. This switching can be invoked by setting the Data Signal Rate Selector (CT111) signal to the modem to true or false. This signal can be set true or false per call (speed switching call dependent) or fixed to the set or the reset value (speed fixed to high-speed or low-speed).0 The switching between low-speed and high-speed is not possible per call. The speed of

the call must now be fixed to the high-speed or the low-speed (see bit 3).1 The switching between low-speed and high-speed is possible per call. Every call holds

additional information which contains the speed. If the speed of the call is smaller than the projected byte 0 (see later on) the low-speed is used.If the speed of the call is higher than the projected byte 0 the high-speed is used.

Bit 3 (speed fixed to high-speed):This bit indicates if the transmission speed of the modem is fixed to high-speed or fixed to low-speed. This bit is used both for leased lines and when the modem is used as convertor.In case of a convertor this bit is only used when bit 2 is 0.0 The speed is fixed to low-speed by means of a constant value of the signal DSRS

(CT111).1 The speed is fixed to high-speed by means of a constant value of the signal DSRS

(CT111).Bit 4 (constant carrier with guarding): only used with leased lines & constant carrierThis bit indicates if the MLU must be blocked if no carrier is detected on the leased line.The MLU expects a constant carrier on the line according to bit 1.0 The service condition of the MLU-circuit is not changed when the DCD signal (CT109)

of the modem is reset. The line is not guarded.1 The service condition of the MLU-circuit is changed to ABL-FAIL when the DCD signal

(CT109) of the modem is reset. The line is considered out of order.Bit 5 (direction call dependent): only used with leased linesThis bit indicates if the MLU is able to set the modem in the calling or in the answering mode by signal Select Transmit Frequency (CT126). If the modem is in the calling modem, the low frequency band is used to send information and the high frequency band is used to receive information. If the modem is in the answering mode the frequency bands are reversed.0 The MLU-circuit is not able to force the modem in the calling or answering mode and

the direction must be fixed to incoming or outgoing (see bit 6).1 The MLU-circuit is able to force the modem in the calling or answering condition by

CT126. The MLU-circuit must be assigned a line number in a bundle with the direction bothway.

Bit 6 (direction fixed): only used with leased lines

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This bit is only used when bit 5 is 0 and the modem cannot be switched between calling and answering mode.0 The direction is fixed to outgoing and the modem is set in the calling mode (send in the

low band).1 The direction is fixed to incoming and the modem is set in the answering mode (send in

the high band).Byte 0 (high convertor speed): only used when modem used as convertorIf the modem is used as a convertor in a modem pool, bit 2 of the subsignalling group indicates if the speed can be switched between the high speed and the low speed by means of CT111 (DSRS). To be able to determine which speed (high or low) is to be used the ISPBX needs a reference. This reference is byte 0. The Compatibility Value for the data party also holds data transfer speed. If the CV-speed indicates that the speed of the call is smaller than the speed indicated by byte 0, the DSRS signal is used to set the modem in the low-speed mode. If the CV-speed indicates the speed of the call is higher (or the same) than the speed indicated by byte 0, the modem is set in the high-speed mode.For each call the calling party-CV is used to determine if the low or the high-speed is to be used. It the calling party-CV is voice (for instance trunk line) the called party-CV is used instead.The relation between the value of this byte and the reference transmission speed is given in table B.4.

Table B-4 Relation byte 0 - convertor speed.

Because the projecting bits of the subsignalling group are not all used for both the leased line and convertor configuration, it is useful to display the relation between these bits. This relation is displayed in diagram Figure C-8 . In this diagram also the standard signalling groups are indicated.

BYTE VALUE

HEXADECIMAL DECIMAL SPEED [bps]

0B 11 50

0C 12 75

0D 13 110

0E 14 150

0F 15 200

10 16 300

11 17 600

12 18 1200

13 19 2400

14 20 3600

15 21 4800

16 22 7200

17 23 9600

18 24 12000

19 25 1200 / 75

1A 26 14400

1B 27 19200

1C 28 38400

1D 29 48000

1E 30 56000

1F 31 64000

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B.6. STANDARD SIGNALLING GROUPS

A number of standard signalling groups are available where the projecting bits and byte are assigned the correct values for specific operation modes. See diagram Figure C-8 .

B.6.1. Modem used as Convertor

When the modem is used in the convertor configuration, the most important bit is bit 0 which determines if the modem is used as convertor or leased line. There are 4 standard signalling groups available for the MLU with the connected modem functioning as convertor. These 4 signalling groups are specified with the values for the projecting bits.

• 1604Modem is used as a pool-modem in the convertor configuration for both incoming and outgoing calls (STF - CT126 switched). The communication speed is fixed to the low speed of the modem (DSRS - CT111 fixed off).

• 1606Modem is used as a pool-modem in the convertor configuration for both incoming and outgoing calls (STF - CT126 switched). The communication speed is fixed to the high speed of the modem (DSRS - CT111 fixed on).

• 1608Modem is used as a pool-modem in the convertor configuration for both incoming and outgoing calls (STF - CT126 switched). The communication speed is call dependent (DSRS - CT111 switched). The speed is switched to the high speed if the CV-speed indicates the communication speed is 1200 bps or higher. The speed is switched to the low speed if the CV-speed indicates the communication speed is less than 1200 bps.

• 160AModem is used as a pool-modem in the convertor configuration for both incoming and outgoing calls (STF - CT126 switched). The communication speed is call dependent (DSRS

BIT 0 BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BYTE 00 0 0 0 0 1 0 H`FF'

don't care don't care don't care don't care don't care


don't care don't care don't care don't care don't care

BIT 0 BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BYTE 00 0 1 0 0 1 0 D`18'

don't care don't care don't care don't care don't care don't care

- CT111 switched). The speed is switched to the high speed if the CV-speed indicates the communication speed is 2400 bps or higher. The speed is switched to the low speed if the CV-speed indicates the communication speed is less than 2400 bps.

B.6.2. Modem used as Leased Line

When the modem is used in the leased line configuration, the most important bit is bit 0 which determines if the modem is used as convertor or leased line. There are 14 standard signalling groups available for the MLU with the connected modem functioning as trunk (leased) line. In the next part of this paragraph, the 14 signalling groups are specified together with the values for the projecting bits and byte.

• 160CModem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line but without guarding the line.When transmitting, the modem uses the low band (STF - CT126 off).The communication speed is fixed to low speed (DSRS - CT111 off).

• 160EModem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line and guards the line.When transmitting, the modem uses the low band (STF - CT126 off).The communication speed is fixed to low speed (DSRS - CT111 off).

• 1610Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line but without guarding the line.When transmitting, the modem uses the low band (STF - CT126 off).The communication speed is fixed to high speed (DSRS - CT111 on).

BIT 0 BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BYTE 00 0 1 0 0 1 0 D`19'

don't care don't care don't care don't care don't care don't care


don't care don't care



89

90

• 1612Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line and guards the line.When transmitting the modem uses the low band (STF - CT126 off).The communication speed is fixed to high speed (DSRS - CT111 on).

• 1614Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line but without guarding the line.When transmitting the modem uses the high band (STF - CT126 on).The communication speed is fixed to low speed (DSRS - CT111 off).

• 1616Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line and guards the line.When transmitting the modem uses the high band (STF - CT126 on).The communication speed is fixed to low speed (DSRS - CT111 off).

• 1618Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line but without guarding the line.When transmitting the modem uses the high band (STF - CT126 on).The communication speed is fixed to high speed (DSRS - CT111 on).

• 161A











Modem is used as a pool-modem in the leased line configuration for outgoing calls only: the MLU expects a constant carrier on the line and guards the line.When transmitting the modem uses the high band (STF - CT126 on).The communication speed is fixed to high speed (DSRS - CT111 on).

• 161CModem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses high or low band (STF - CT126 switched).The communication speed is fixed to low speed (DSRS - CT111 off).

• 161EModem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses high or low band (STF - CT126 switched).The communication speed is fixed to high speed (DSRS - CT111 on).

• 1620Modem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses low band (STF - CT126 off).The communication speed is fixed to low speed (DSRS - CT111 off).

• 1622Modem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses low band (STF - CT126 off).The communication speed is fixed to high speed (DSRS - CT111 on).




don't care don't care don't care don't care


don't care don't care don't care don't care


don't care don't care don't care

91

92

• 1624Modem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses high band (STF - CT126 on).The communication speed is fixed to low speed (DSRS - CT111 off).

• 1626Modem is used as a pool-modem in the leased line configuration for both incoming and outgoing calls: the MLU does not expect a constant carrier on the line.When transmitting the modem uses high band (STF - CT126 on).The communication speed is fixed to high speed (DSRS - CT111 on).







C . SOPHO-LAM CONVERTOR

The SOPHO-LAM P375 convertor can be used instead of the MLU convertor. This appendix describes the details of the SOPHO-LAM convertor configuration. Chapter 3 contains the general information.

C.1. DTE-MODE

When the SOPHO-LAM P375 (release 3) is used in a convertor configuration it has to operate in `DTE mode'. In this mode the V.24 interface of the SOPHO-LAM operates as a DTE, so a DCE (modem) can be connected. However, the interace does NOT exactly operate according to the V.24 recommendations. Therefore a special cable has to be used between the SOPHO-LAM and the convertor modem (see section C.2. V.24 CABLE BETWEEN SOPHO-LAM AND MODEM).

The SOPHO-LAM is set in the DTE-mode using special sub-signalling groups. These subsignalling groups are:

The basic functions of the SOPHO-LAM operating in DTE mode can be divided in three parts: basic functions during an incoming call, during an outgoing call and during idle state.

Note: active signal = ON-state of V.24 circuit;deactive signal = OFF-state of V.24 circuit.

• Incoming callWhen the modem detects an incoming call it activates CT125. This circuit is connected to CT141 of the SOPHO-LAM.The SOPHO-LAM detects an active signal at CT141 and in return activates CT107.CT107 is active as long as the call exists. When the call is cleared, the SOPHO-LAM deactivates CT107.CT107 is connected to CT108 of the modem.Now the modem detects an active signal at CT108 and in return activates CT107. This circuit is connected to CT108 of the SOPHO-LAM (the call is answered by the modem).

• Outgoing call

- for a DLC-A/B/C and D : 280C;- for a DTX-I, DLC-I and DLC-U: 0910.

93

94

When the SOPHO-LAM wants to make an outgoing call, it activates CT107.The modem detects an active signal on CT108, now there are two possibilities: - in CT108.1 mode (Connect Data Set to Line) the convertor modem sets up the

connection with the remote modem;- in CT108.2 mode (Data Terminal Ready) the modem waits for dial information (for

example Hayes commands).

• Idle stateIn idle state CT107 of the SOPHO-LAM is OFF.

The extended functions of the SOPHO-LAM operating in DTE mode are as follows:

- The SOPHO-LAM can select the calling or answering mode of the modem via CT142. Output circuit CT142 of the SOPHO-LAM is connected to circuit CT126 of the modem. CT142 is programmable. When CT142 is active the modem transmits in the high frequency channel, otherwise in the low frequency channel.

- The SOPHO-LAM can be programmed via the V.24 interface. This way of programming can be protected with a password.

Table C-1 Default Parameter Settings of SOPHO-LAM in DTE-mode.

For correct convertor operation, in general the convertor modem has to operate as follows:

- CT125 indicates an incoming call;- when CT108 changes from ON to OFF, the modem has to go on hook;- CT109 indicates detection of an incoming carrier;- for synchronous transmission the modem should accept the transmit clock from the

SOPHO-LAM on CT113;- CT107 indicates the condition of the analogue line (normal operation according to V.24

PARAMETERS DEFAULT SETTINGS

PARAMETERS DEFAULT SETTINGS

CT108 as request: No Incoming guard (sec): 60 seconds

CT108 assumed on: No Xon character: 017

CT105 as request: No Xoff character: 019

CT103 as request No Transmission: Asynchronous

CT107 as clear: No Mode: Full duplex

CT107 assumed on: No Speed: 1200 bits/sec

Auto answer: Yes Format (bits): 8 bits

Connect CT105&CT109:

No Format (parity): No parity

CT109 enables CT106: No Format (stopbits): 1 stop bit

Connect CT105&CT106:

No Echo characters Yes

CT105 assumed on: No Upper case: Yes

Dataguarding: No Calling number: No

Incoming guarding: No Flow control: No

Break call clear: No NIC: Yes

Autobaud detection: No Rate adaption: Proprietary

Autoparity detection: No Protocol: Keyboard

Flow control: Xon/Xoff Logoff: No logoff string

CT142 control: Auto Password: PROGRAM DCE

Dataguard (min): 3 minutes

95

96

specifications).This means the following: - CT107 is OFF in the idle state;- CT107 goes OFF when the Hang Up process is started;- CT107 goes ON as soon as the connection set up is started;- CT107 goes ON in the V.25(bis) dialog mode.

Note: Different convertor settings are used for the leased and switched line configuration. Please refer to section C.3 and C.4.

C.2. V.24 CABLE BETWEEN SOPHO-LAM AND MODEM

When the SOPHO-LAM is used in a convertor configuration it must operate in the DTE mode. In this mode the test circuits CT141 and CT142 are used to provide full DTE functionality. So, a few V.24 circuits are not used according to the CCITT V.24 recommendations. Therefore a special cable has to be used between the SOPHO-LAM and the modem. Figure Figure C-1 V.24 Cable between SOPHO-LAM P375 and MODEM. shows the cable layout and table C.2. V.24 CABLE BETWEEN SOPHO-LAM AND MODEM shows the circuit connections.

Figure C-1 V.24 Cable between SOPHO-LAM P375 and MODEM.

25-pinConnector male(soldering side)

25-pinConnector male(soldering side)

Seen from wiring side

Pin Pin 1

13

14

25

CABLE CONNECTORAT SOPHO-LAM SIDE

CABLE CONNECTORAT MODEM SIDE

1

13

17

18

17

18

2

3

4

6

7

24

25

208

22

11

2

3

4

6

7

24

25

208

22

11

Circuit

CT103 - A

CT104 - B

CT105 - CCT115 - D

CT141 - ECT107 - F

CT102 - G

CT113 - L

CT142 - M

CT108 - HCT109 - I

CT125 - J

CT126 - K

Circuit

B - CT103

A - CT104

I - CT105L - CT115

J - CT141H - CT107

G - CT102

D - CT113

K - CT142

F - CT108C - CT109

E- CT125

M - CT126

97

98

Table C-2 Cable Definition.

CT125 of the SOPHO-LAM is always OFF, also during an incoming call to the SOPHO-LAM. The reason for this is that CT125 of the modem is used and CT125 of the SOPHO-LAM is NOT used. For practical reasons the special cable is made symmetric. To prevent that the Local Loop Back of the modem is activated, CT125 of the SOPHO-LAM is forced to OFF during all states of the SOPHO-LAM.

The following subsections describe the operation of the SOPHO-LAM convertor in a leased and switched line configuration.

C.3. LEASED LINE CONFIGURATION

Figure Figure C-2 Leased Line Configuration with SOPHO-LAM convertor. shows the leased line configuration with SOPHO-LAM convertor.

SOPHO-LAM CONNECTOR MODEM CONNECTOR

PIN CIRCUIT MNEMONIC

PIN CIRCUIT MNEMONIC

7 CT102 GND Connected to 7 CT102 GND

3 CT104 RCD Connected to 2 CT103 TMD

2 CT103 TMD Connected to 3 CT104 RCD

8 CT109 DCD Connected to 4 CT105 RTS

4 CT105 RTS Connected to 8 CT109 DCD

20 CT108 DTR Connected to 6 CT107 DSR

6 CT107 DSR Connected to 20 CT108 DTR

24 CT113 TSET Connected to 17 CT115 RSET

17 CT115 RSET Connected to 24 CT113 TSET

18 CT141 LL Connected to 22 CT125 CI

22 CT125 CI Connected to 18 CT141 LL

25 CT142 TI Connected to 11 CT126 STF

11 CT126 STF Connected to 25 CT142 TI

Figure C-2 Leased Line Configuration with SOPHO-LAM convertor.

The convertor modem (MODEM-A) has to be configured as follows:

- Leased line configuration;- CT108 always ON (Hayes command AT&DO);- CT107 indicates the clearing of the analogue connection (according to the V.24

specification, Hayes command AT&S1);- Automatic answering ON (Hayes command ATS0=1);- modem operates in silent mode (result codes disabled, Hayes command ATQ1);- CT109 is ON when the analogue connection is present (according to the V.24

specification).

With this configuration there is a permanent connection between the modems as long as the remote terminal is operational. So, the connection is only cleared when the remote terminal is switched off.

In the following sub-sections the operation of the SOPHO-LAM convertor configuration is described without dialling protocol information. So, the required V.25bis, Hayes and keyboard dialling commands are not described. For a detailed description of these commands, refer to


64 kbpsIMP

64 kbps

V.24

DCE SOPHO-LAM

DLC/DTX-I

DLC/DTX

SN 2 3

4

4

1 1

MODEM

MODEM

PSTN Leased line




Modulated carrier.

TA = Terminal Adapter


DTE-A

DTE-B

MODEM - A

MODEM - B

TA-A TA-B

1

3

2

4

99

10

the user guide of the SOPHO-LAM P375 and the modems used.

C.3.1. Incoming Call

When DTE-B activates CT108, MODEM-B sends a carrier over the line to MODEM-A. When MODEM-A detects the incoming carrier, it answers the call automatically and activates both CT107 and CT109 (CT108 of MODEM-A is continously ON). CT107 is connected to CT108 of the SOPHO-LAM, so the SOPHO-LAM knows that MODEM-A is ready and the analogue connection is established.

• Call request to SOPHO-LAMThe call request and clearing operation of the SOPHO-LAM convertor depends on the data parameter settings. For example, one of the following data parameters settings can be used: - CT105 initiates call request;- CT103 initiates call request.When CT105 is used as call request, the carrier of MODEM-B initiates a call request via CT109 (DCD) of MODEM-A. In this case the connection between DTE-A and the SOPHO-LAM convertor is cleared when the leased line connection is out of synchronisation. Note that CT105 can only be used as call request provided CT108 and CT107 are ON.When CT103 is used as call request, DTE-B can initiate a call request by typing some characters. Note that CT103 can only be used as call request provided CT108, CT107, CT105 and CT106 of the SOPHO-LAM are ON.After the call request the SOPHO-LAM establishes a connection to a fixed destination. The SOPHO-LAM uses either Predefined Destination Dialling, the hotline facility or keyboard dialling.

• Call clearingIn both situations (CT105 and CT103 as call request) the connection between DTE-A and the SOPHO-LAM can be cleared using one of the following methods: - data guarding;- break sequence initiates call clear;- hang up with Hayes command ATH0.The SOPHO-LAM can be programmed to use data guarding. Use menu option `Data guard active' or `Data guard on incoming call active' (please refer to the Customer Engineer manual of the SOPHO-LAM P375). In this situation the SOPHO-LAM clears the call when there has been no activity on CT103 and CT104 for a period of time (data guarding time in minutes). It is also possible to check only the activity on CT103 after an incoming call has been answered (data guarding time in seconds).In asynchronous transmission calls can be cleared when a break sequence is detected at the speed set in the Transmission Speed menu. Use menu option `Break Initiates Call

0

Clear'. So, DTE-B can clear the call by sending a break sequence.When DTE-B uses Hayes command ATH0 (hang up) and the SOPHO-LAM is in the Hayes mode, then the SOPHO-LAM goes on hook and the digital connection through the switch is cleared. So, the ATH0 command is received by and executed by the SOPHO-LAM.

C.3.2. Outgoing Call

When DTE-A dials the convertor group DNR, one of the convertors is selected and the corresponding SOPHO-LAM activates CT107. This circuit is connected to CT108 of MODEM-A. In return the MODEM-A activates CT107 which is connected to CT108 of the SOPHO-LAM. At this moment the SOPHO-LAM accepts the call from DTE-A. Because the analogue connection is already present, DTE-A is directly connected to DTE-B.

If the analogue connection is not present, the MODEM-A does not return CT109. In this situation the SOPHO-LAM does not accept the call. The call clearing possibilities are the same as described in section C.3.1. Incoming Call

C.4. SWITCHED LINE CONFIGURATION

Figure Figure C-3 Switched Line Configuration with SOPHO-LAM convertor. shows the switched line configuration with SOPHO-LAM convertor.

101

10

Figure C-3 Switched Line Configuration with SOPHO-LAM convertor.

As described in section 3.1.2. Data Terminal Connected to a DLC/DTX (CONVERTORS) the SOPHO-LAM convertor configuration for switched lines can NOT be used for both incoming and outgoing calls (direction of call set-up). The reason for this is that both configurations use different convertor settings.

The convertor modems in a pool for incoming calls should be configured as follows:

- Switched line configuration;- silent mode (result codes disabled, Hayes command ATQ1);- Automatic answering ON (Hayes command ATS0=1);- CT107 indicates the state of the analogue connection (according to the V.24 specification,

Hayes command AT&S1);- when CT108 changes from ON to OFF the modem must go on hook (Hayes command


64 kbpsIMP

64 kbps

V.24

DCE SOPHO-LAM

DLC/DTX-I

DLC/DTX

SN 2 3

4

4

1 1

MODEM

MODEM

PSTN




Modulated carrier.

TA = Terminal Adapter


DTE-A

DTE-B

MODEM - A

MODEM - B

TA-A TA-B

1

3

2

4

IMP64 kbps

IMP64 kbps

ALC

ATU

Trunk line

2

AT&D2).

The convertor modems in a pool for outgoing calls should be configured as follows:

- Switched line configuration;- non-silent mode (result codes enabled, Hayes command ATQ0);- CT107 indicates the state of the analogue connection (according to the V.24 specification,

Hayes command AT&S1);- when CT108 changes from ON to OFF the modem must go on hook (Hayes command

AT&D2).

C.4.1. Incoming Call

Figure Figure C-4 Call Phase Diagram for an Incoming Call. shows the call phase diagram for an incoming call. In order to understand the call phase diagram note the following:

- a circuit number means that the circuit is in the ON state (active);- a circuit number followed by a `O' means that the circuit is in the OFF state (deactive);- the conversation mode during data transfer and clearing is not described (CT105 and

CT109 interactions).

DTE-B dials the convertor group DNR (ALC side of convertor pool) using for example Hayes commands.

MODEM-A detects an incoming call (ring current) and activates CT125. In return the SOPHO-LAM activates CT107 which is connected to CT108 of MODEM-A. Because MODEM-A operates in the automatic answering mode, it answers the call after receiving an active CT108. The SOPHO-LAM keeps CT107 active as long as the call exists.

103

10

Figure C-4 Call Phase Diagram for an Incoming Call.• Call request to SOPHO-LAM

The call request and clearing operation of the SOPHO-LAM convertor depends on the data parameter settings. Normally the SOPHO-LAM receives a call request via CT125 of MODEM-A. But there are also other possibilities. For example, one of the following data parameters settings can be used: - CT105 initiates call request;- CT103 initiates call request;- CT108 initiates call request.When CT105 is used as call request, the carrier of MODEM-B initiates a call request via CT109 (DCD) of MODEM-A. In this case the connection between DTE-A and the SOPHO-LAM convertor is cleared when the line connection is out of synchronisation.

DTE-A

USER-A USER-BDIGITAL CONNECTION CONVERTOR ANALOGUE CONNECTION

TA-A ISPBX ISPBXSOPHO-LAM MODEM-A MODEM-B DTE-B

CT108

CT105RINGING

CT108CT107

Call requestOFF HOOK

CT105CT109

CT105CT109

CT141CT125

ANSWER

ANSWERCONNECT

ANSWER

CT107CT108

CT109CT105

CARRIER

CARRIER

SYNCHRONISATION

VIA FRAME BIT

VIA FRAME BIT

CT107

CT109

CT109

CT109

SETUP

SETUPINC. CALL

CT125

CT108

CT105

when usinghot line orPDD

4

Note that CT105 can only be used as call request provided CT108 and CT107 of the SOPHO-LAM are ON.It is useful to use CT105 as call request when the connection can not be cleared via CT107 of MODEM-A. In this case you can clear the connection via CT109 of MODEM-A.When CT103 is used as call request, DTE-B can initiate a call request by typing some characters. Note that CT103 can only be used as call request provided CT108, CT107, CT105 and CT106 of the SOPHO-LAM are ON.When CT108 is used as call request, the request is initiated by CT107 of MODEM-A. After answering the call, MODEM-A activates CT107.After the call request, DTE-B can dial the DNR of DTE-A using one of the dialling option of the SOPHO-LAM.

• Call set-up to DTE-AAfter the connection between the modems is established, DTE-B has a transparent connection with the SOPHO-LAM convertor. Now DTE-B can dial the DNR of DTE-A using one of the dialling protocols offered by the SOPHO-LAM (keyboard dialling, Hayes commands or V.25bis).TA-A activates CT125 after receiving an incoming call. TA-A answeres the call either after receiving an active CT108 or directly when CT108 is already present.After synchronisation and after DTE-A has activated CT105, MODEM-A receives an active CT105. The reason for this is that the condition of CT105 of DTE-A is passed through to MODEM-A via a frame bit (Proprietary protocol, V.110 or X.30). In fact,the condition of CT105 of DTE-A is transferred to CT109 of the SOPHO-LAM, and CT109 of the SOPHO-LAM is connected to CT105 of MODEM-A.Meanwhile, CT109 of MODEM-A is active, so the SOPHO-LAM is still receiving an active signal at CT105. After synchronisation the active condition of CT105 is signalled to CT109 of TA-A via a frame bit.After these interactions there is a transparent connection between DTE-A and DTE-B.

C.4.2. Outgoing Call

Figure Figure C-5 Call Phase Diagram for an Outgoing Call. shows the call phase diagram for an outgoing call.

105

10

Figure C-5 Call Phase Diagram for an Outgoing Call.

DTE-A dials the convertor group DNR using for example Hayes commands.

The SOPHO-LAM automatically answers the call, and activates CT107. Now MODEM-A detects that the `terminal' is present (CT108.2 mode). After synchronisation the active condition of CT105 from DTE-A is signalled to CT109 of the SOPHO-LAM via a frame bit. CT109 is connected to CT105 of MODEM-A.

MODEM-A receives an active signal at CT105 an goes off hook. Now DTE-A has a transparent connection with the MODEM-A. Note that MODEM-A in figure Figure C-5 Call Phase Diagram for an Outgoing Call. operates in the CT108.2 mode. Otherwise MODEM-A would

DTE-A



RINGING

ANSWERCONNECT

ANSWER

ANSWER

CT107CT108

CT109CT105

CT108CT107

CT105CT109

CARRIER

SYNCHRONISATION

VIA FRAME BIT

VIA FRAME BIT

CT107

CT105

CT109

CT108

CT109

INC. CALL

CT125

CT108

CT105

OFF HOOK

OFF HOOK

when modemoperates in

CT108.1 mode

CT108.2mode

SETUPSETUP

6

go off hook after receiving an active CT108.

After the connection between DTE-A and the SOPHO-LAM is established, DTE-A can dial the number of DTE-B using one of the dial options of MODEM-A, for example Hayes commands.

MODEM-B detects an incoming call and activates CT125. In return DTE-B activates CT108 and MODEM-B answeres the call. Now MODEM-B activates CT107 and DTE-B in return activates CT105, after which the carrier is transmitted to MODEM-A. After the carriers are present, both modems activate CT109. The active CT109 of MODEM-A is signalled to TA-A (via the Proprietary protocol, V.110 or X.30), after which TA-A also activates CT109.

After these interactions there is a transparent connection between DTE-A and DTE-B.

C.4.3. Call Clearing from the ISPBX side

Figure Figure C-6 Call Phase Diagram for Call Clearing from ISPBX side. shows the call phase diagram for clearing a call from the ISPBX side.

Figure C-6 Call Phase Diagram for Call Clearing from ISPBX side.

DTE-A



CT109CT105

CT107CT108

CT108CT107

CLEAR

CT108

CT109

CT107

CT108

OFF

OFF

OFF

OFF

ON HOOKON HOOK

ON HOOKNO SYNC.

OFF OFFON HOOK

ON HOOK

107

10

DTE-A clears the call by deactivating CT108 (for example). As a result TA-A goes on hook and a `Clear' message is passed through to the SOPHO-LAM. After reception of this message the SOPHO-LAM deactivates CT109 and CT107. In return MODEM-A goes on hook and deactivates CT107. MODEM-B detects that the convertor modem is on hook (carrier lost) and deactivates CT109 and CT107. In return DTE-B deactivates CT108 and MODEM-B goes on hook.

C.4.4. Call Clearing from the Remote side

Figure Figure C-7 Call Phase Diagram for Call Clearing from Remote side. shows the call phase diagram for clearing a call from the ISPBX side.

Figure C-7 Call Phase Diagram for Call Clearing from Remote side.

DTE-B clears the call by deactivating CT108. As a result MODEM-B goes on hook and MODEM-A deactivates CT109. The condition of CT109, connected to CT105 of the SOPHO-LAM, is signalled to CT109 of TA-A via a frame bit. Meanwhile MODEM-A also deactivates CT107 after which the SOPHO-LAM goes on hook. This is signalled to TA-A using a `clear' message, after which TA-A deactivates CT107. In return DTE-A deactivates CT108 after which TA-A goes on hook.

DTE-A



CT105CT109

CT108CT107

CT107CT108

CT108

CT109OFF

CT107OFF

CT108OFF

OFF

ON HOOKON HOOK

ON HOOK

ON HOOK

NO SYNC.

OFF

OFF

OFF

OFFCLEAR

ON HOOK

VIA FRAME BIT

8

Figure C-8

STA

RT

bit 4

(con

st c

arr w

ith g

uard

) :d

on’t

care

bit 4

(con

st c

arr w

ith g

uard

) :d

on’t

care

bit 4

(con

st c

arr w

ith g

uard

) :d

on’t

care

bit 3

(spe

ed fi

xed

high

) :do

n’t

care

bit 5

(dire

ct c

all d

epen

d) :d

on’t

care

bit 5

(dire

ct c

all d

epen

d) :d

on’t

care

bit 2

(spe

ed s

with

cal

l dep

) :d

on’t

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109

fdex810e

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Transcript of fdex810e