Data Communications Problems

8/12/2019 Data Communications Problems

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UART

Reported by: Estrella, Recuerdo Jr. C.

Gagui, John Gregory R.

1. What is used for asynchronous

transmission of serial data betweena DTE and a DCE?

a. UART

b. USRT

c. QART

d. CPU

2. It's a physical memory location in

the CPU that allows quick data

manipulation.

a. Buffer register

b. Internal registers

c. Control register

d. Transmit buffer register

3. What is used to buffer outgoing

characters?

a. Buffer register

b. Internal register

c. Transmit buffer register

d. Control register

4. It holds the contents of the memory

which are to be transferred from

memory to other components.a. Buffer registers

b. Internal register


d. Control register

5. It is a processor register which

changes or controls the general

behavior of a CPU or other digital

device.

a. Buffer registers

b.

Internal registerc. Transmit buffer register

d. Control register

6. It is an n-bit data registers that

keeps track of the status of the

UART's transmit and receive buffer

registers.

a. Buffer registers

b. Status register


d. Control register

7. The only bit in the UART that is not

optional or programmable.

a. Stop bitb. Parity bit

c. Start bit

d. Bit rate

8. Status condition where transmit

shift register has completed

transmission of a data character.

a. RPE (receive parity error)

b. TBMT (transmit buffer empty)

c. RFE (receive framing error)

d. ROR (receive overrun)

9. Status condition that is set when a

received character has a parity error

in it.






character is received without any or

with an improper number of start

bits.a. RPE (receive parity error)





character in the receive buffer

register is written over by another

receive character because the CPU

failed to service an active condition

on REA before the next characterhas been received from receive shift

register.







12. Status condition where a data

character has been received and

loaded into the receive data

register.


b. RDA (receive data available)c. RFE (receive framing error)


13. It is the fundamental method of

conversion between serial and

parallel forms.

a. Shift register

b. Transmitter

c. Modulation

d. Receiver

14. The difference in time between the

beginning of a start bit and when it

is detected.

a. Parity error

b. Bit error rate

c. Detection error

d. Probability error

15. It is the difference in the arrival time

between two sequentially-adjacent

registers.

a. Clock rate

b. Clock skewc. Clock difference

d. Clock block

16. What is used for synchronous

transmission of serial data between

a DTE and a DCE?

a. UART

b. USRT

c. QART

d. CPU

17. Any binary digital device thatgenerates, transmits, receives, or

interprets data messages.

a. DCE

b. DOE

c. DTE

d. DRE

18. It is a general term used to describe

equipment that interfaces data

terminal equipment to a

transmission channel.

a. DCE

b. DOEc. DTE

d. DRE

19. The maximum character length in

UART is __________.

a. 8 bits

b. 9 bits

c. 10 bits

d. 11 bits

20. Using a 22-bit character format with

ASCII encoding is called __________.

a. Full ARQ

b. Full Baudot

c. Full ASCII

d. Full QAM

SERIAL INTERFACES

Reported by: Espedillon, Marigold May L.

Grageda, Glenda Mae V.

Gargoles, Jobert S.Herrera, Erika Claudine G.

1. Which of the following must a serial

interface provide?

a. A specific range of voltages for

transmit and receive signal levels

b. Limitations for the electrical

parameters of the transmission

line

c.

Standard cable and cableconnections

d. All of the above

2. It is sometimes referred to as the

EIZ-232 standard Versions C and E of

the RS-232 standard.

a. RS-232A

b. RS-232B



c. RS-232C

d. RS-232D

3. It is designed for transporting

asynchronous data between a DTE

and a DCE or between DTEs.

a. 9-pin Version of RS-232b. 10-pin Version of RS-232

c. 11-pin Version of RS-232

d. 12-pin Version of RS-232

4. It is designed for transporting either

synchronous or asynchronous data

between a DTE and a DCE.

a. 24 pin Version

b. 25 pin Version

c. 26 pin Version

d. 25 pin Version

5. It is designed for dial-up telephone.

a. EIA-560

b. EIA-561

c. EIA-562

d. EIA-563

6. It converts the internal voltage

levels from the DTE and DCE to RS-

232 values.

a. Voltage-Leveling Circuits

b. Driver

c. Terminator d. RS

7. It means “Recommended

Standards”.


b. Driver

c. Terminator

d. RS

8. A voltage leveler wherein its output

signals onto the cable.

a.

Voltage-Leveling Circuitsb. Driver

c. Terminator

d. RS

9. It accepts signals from the cable.


b. Driver

c. Terminator

d. RS

10. The RS-449 has a total of

__________.

a. 46 pins

b. 47 pins

c. 48 pinsd. 49 pins

11. Two categories of RS-449 Serial

Interface.

a. Category A and Category B

b. Category I and Category II

c. Category C and Category D

d. Category 1 and Category 2

12. One of the 10 circuits in RS-449 used

by the DTE to request a local

loopback from the DCE.

a. Local Loopback

b. Remote Loopback

c. Select Frequency

d. Test Mode


by the DTE to request a remote

loopback from the distant DCE.

a. Local Loopback

b. Remote Loopback

c. Select Frequency

d. Test Mode14. One of the 10 circuits in RS-449

allows the DTE to select the DCE’s

transmit and receive frequencies.

a. Local Loopback

b. Remote Loopback

c. Select Frequency

d. Test Mode


by the DTE to signal the DCE that a

test is in progressa. Local Loopback

b. Remote Loopback

c. Select Frequency

d. Test Mode

16. One of the 10 circuits in RS-449

common return wire for unbalanced



signals propagating from the DCE to

the DTE.

a. Terminal in Service

b. Receive Common

c. Select Standby

d. New Signal17. One of the 10 circuits in RS-449 used

by the DTE to signal the DCE

whether it is operational.


b. Receive Common

c. Select Standby

d. New Signal


by the DTE to request that the DCE

switched to standby equipment.


b. Receive Common

c. Select Standby

d. New Signal


with a modem at the primary

location of a multipoint data circuit.


b. Receive Common

c. Select Standby

d. New Signal20. It was intended to operate at data

rates between 20kbps and 2Mbps

using the same DB25 connector.

a. RS-232

b. RS-233

c. RS-449

d. RS-530

DATA COMMUNICATIONS MODEMS

Reported by: De Leon, Charlene Ann C.

Guevara, Arnelson D.

1. What is/are the other name/s of

Data Communications Modem?

a. Datasets

b. Dataphones

c. Modems

d. All of the above

2. DCE stands for?

a. digital communication

equipmentb. digital communication encoder

c. data communication equipment

d. data communication encoder

3. The approximated bandwidth used

for transporting analog voice signals.

a. 300 kHz – 3000 kHz

b. 300 Hz – 3000 Hz

c. 30 kHz – 300 kHz

d. 30 Hz – 300 Hz

4. The rate of change of signals on the

transmission medium after encoding

and modulation have occurred

a. Baud

b. Bit

c. Byte

d. Data

5. It interfaces the modem transmitter

and receiver to the serial interface.

a. Serial interface circuit

b. Modulator circuit

c. Telco interface circuitd. Demodulator circuit

6. The rate of change of the digital

information signal

a. Baud

b. Bit

c. Byte

d. Data

7. A special internally generated bit

pattern in transmit modem

a.

Parity bitb. Training sequence

c. Marking parity

d. Parity

8. It is used to match the impedance of

the modem to the impedance of the

telephone line and regulate the

amplitude of the transmit signal.



a. Bandpass filter and equalizer

circuit

b. Modulator circuit

c. Demodulator circuit

d. Telco interface circuit

9. It produces the analog carriersnecessary for the modulation and

demodulation process.

a. Bandpass filter and equalizer

circuit

b. Carrier generation circuit

c. Clock generation circuit

d. None of the above

10. High-speed synchronous voice band

modems operate at what

frequency?

a. 9600 bps, 16 QAM

b. 9600 bps, 8-PSK

c. 2400 bps, 16 QAM

d. 2400 bps, 8-PSK

11. Modulation scheme used in medium

speed synchronous voice-band

modems

a. FSK

b. PSK

c. QAM

d. ASK12. It converts the digital pulses to

analog signals.

a. DCE

b. DAC

c. Both a and b


13. The specification of the old Bell type

103 modem were:

a. 600 bps, full duplex, FSK

b.

600 bps, half duplex, FSKc. 300 bps, full duplex, FSK

d. 300 bps, half duplex, FSK

14. These are low speed voice band

modems.

a. Synchronous modems

b. Asynchronous modems

c. Isochronous modems


15. Asynchronous modems used what

scheme of modulation?

a. ASK

b. FSK

c. Both a and bd. None of the above

16. Application of asynchronous voice-

band modems

a. Telemetry

b. Caller ID

c. Both a and b


17. Capable of operating at full duplex

over a two-wire telephone line at

300 bps.

a. Bell System 202T

b. Bell System 202S

c. Bell System 103

d. Bell System201

18. Bell System 202 modem has ______

baud rate.

a. 300

b. 600

c. 900

d. 1200

19. It is when asynchronous data istransported by asynchronous

modem.

a. Bus

b. Isochronous transmission

c. Data transmission

d. Training sequence

20. It uses PSK or QAM to transport

data.

a. Synchronous modems

b.

Asynchronous modemsc. Isochronous modems




ITU-T MODEM RECOMMENDATIONS

Reported by: De Jesus, Juan Miguel D.

Legaspi, Kenneth R.

1. The ITU-T specifications are known

as __________.a. EBCDIC

b. X-series

c. V-series

d. ASCII

2. The ITU-T V.29 specification is the

first internationally accepted

standard for __________ data

transmission rate.

a. 9600 bps

b. 1200 bps

c. 2400 bps

d. 4800 bps

3. Pseudo full-duplex operation can be

achieved over two-wire lines using a

method called __________.

a. ping

b. ping-pong

c. pong

d. none of these

4. In V.32, what advanced coding

technique is used?a. Baudot

b. Discrete

c. Continuous

d. Trellis

5. The constellation diagram for 32-

sate trellis encoding was developed

by __________.

a. Dr. Ungerboeck

b. Thomas Murray

c.

Emile Baudotd. Konrad Zuis

6. Full-duplex operation over two-wire

switched telephone lines is achieved

with V.32 using a technique called

__________.

a. QAM constellation

b. statistical duplexing

c. echo cancellation

d. none of these

7. ITU-T recommendation V.32bis was

introduced in the year __________.

a. 1990

b. 1991c. 1992

d. 1993

8. V.32bis uses a __________ signal

constellation with each signalling

condition representing 6 bits of

data.

a. 16-point

b. 32-point

c. 48-point

d. 64-point

9. __________ feature slowly reduces

the transmission bit rates to 12.2

kbps, 9.6 kbps, or 4.8 kbps if the

quality of the communication line

degrades on V.32bis.

a. Fall-back

b. Fall-forward

c. Ping-pong

d. Echo Cancellation

10. In V.32bis, __________ feature gives

the modem the ability to return tothe higher transmission rate when

the quality of channel improves.

a. fall-back

b. fall-forward

c. ping-pong

d. echo cancellation

11. The __________ signal constellation

is used on V.33.

a. 128-point

b.

64-pointc. 32-point

d. 16-point

12. This ITU-T standard is used in

electrocardiogram over telephone

lines.

a. V.13

b. V.14



c. V.15

d. V.16

13. This standard limits the output

power levels of modems used on

telephone lines.

a. V.5b. V.4

c. V.2

d. V.1

14. This standard is focused on the

maintenance of international data

circuits.

a. V.50

b. V.51

c. V.52

d. V.53

15. This ITU-T standard was accepted in

the year 2000.

a. V.92

b. V.100

c. V.110

d. V.120

16. The ITU-T developed the

__________ specification in

February 1998 during a meeting in

Geneva, Switzerland.

a. V.56b. V.57

c. V.90

d. V.92

17. This standard is an enhancement

adopted by the ITU in 1996.

a. V.31bis

b. V.34t

c. V.42bis

d. V.32terbo

18. This is a standard for acousticalcouplers.

a. V.13

b. V.14

c. V.15

d. V.16

19. This is a standard for loop test

devices for modems.

a. V.51

b. V.52

c. V.53

d. V.54

20. This standard defines binary 0/1

data bits as space/mark lineconditions.

a. V.1

b. V.2

c. V.4

d. V.5

DATA LINK PROTOCOL FUNCTION S

Reported by: Dela Cruz, Eraldus Mico P.

De Belen, Eldridge Angelo P.

1. What is the protocol layer that

transfers data between adjacent

network nodes in a wide area

network?

a. Data Link Layer

b. Physical Layer

c. Application Layer

d. Session Layer

2. Which is not a function of Data Link

layer?a. Error Control

b. Line Discipline

c. Data Encryption

d. Flow Control

3. It determines which device can send

and when it can send.

a. Error Control

b. Line Discipline

c. Data Encryption

d.

Flow Control4. It defines a set of procedures that

tells the transmitting station how

much data it can send.

a. Error Control

b. Line Discipline

c. Data Encryption

d. Flow Control



5. It is concerned primarily with error

detection and message

retransmission.

a. Error Control

b. Line Discipline

c. Data Encryptiond. Flow Control

6. Which is not a part of Line

Discipline?

a. Enquiry

b. Acknowledgement

c. Poll/Select

d. Stop-and-wait

7. The response to enquiry when the

receiver is not ready to receive.

a. Positive Acknowledgement

b. Negative Acknowledgement

c. Balance Acknowledgement

d. Zero Acknowledgement

8. The response to enquiry when the

receiver is ready to receive.

a. Positive Acknowledgement

b. Negative Acknowledgement

c. Balance Acknowledgement

d. Zero Acknowledgement

9. It is a solicitation sent from the

primary to a secondary to determineif the secondary has a data to

transmit.

a. Poll

b. Addresses

c. Selection

d. Enquiry

10. It is how the primary designates a

secondary as a destination or

recipient of data.

a.

Pollb. Addresses

c. Selection

d. Enquiry

11. ARQ stands for __________.

a. Amplified Resonance Query

b. Automatic Repeat Question

c. Amplified Resonance Request

d. Automatic Repeat Request

12. EOT stands for

a. Enquiry of Transfer

b. End of Transfer

c. Enquiry of Transmit

d. End of Transmit13. It uses a window size to control the

number of unacknowledged frames

outstanding?

a. Poll/Select

b. ENQ/ACK

c. Stop-and-Wait ARQ

d. Go-back-n ARQ

14. The source transmits a single frame,

and waits for an ACK.

a. Poll/Select

b. ENQ/ACK

c. Stop-and-Wait ARQ

d. Go-back-n ARQ

15. A source station can transmit

several frames in succession before

receiving an acknowledgement.

a. Stop-and-Wait ARQ

b. Go-back-n ARQ

c. Stop-and-Wait Flow control

d. Sliding Window Flow control

16. Header of a frame generallycontains __________.

a. synchronization bytes

b. addresses

c. frame identifier

d. all of the above

17. When 2 or more bits in a data unit

have been changed during the

transmission, the error is called

__________.

a.

Random errorb. Burst error

c. Inverted error


18. Which one of the following is a data

link protocol?

a. Ethernet

b. Point-to-Point Protocol



c. HDLC

d. All of the above

19. Which sublayer of the data link layer

performs data link functions that

depend upon the type of medium?

a. Logical Link Control Sublayerb. Media Access Control Sublayer

c. Network Interface Control

Sublayer


20. CRC stands for __________.

a. Cyclic Redundancy Check

b. Code Repeat Check

c. Code Redundancy Check

d. Cyclic Repeat Check

CHARACTER- AND BIT-ORIENTED DATA-

LINK PROTOCOLS

Reported by: Abrogueña, John Raymond

Lim, Jermaine B.

1. Protocols that transmit and control

information either in separate

control frames or in the form of

overhead that is added to the dataand included in the same frame.

a. Overhead Protocol

b. Control Protocol

c. Data-Link Protocol

d. Bit-Oriented Protocol

2. Data-link protocols can be classified

as __________.

a. Bit-oriented or Character-

oriented

b.

Data-oriented or Modem-Oriented discern

c. a and b

d. none of the above

3. Interprets a frame of data as a group

of successive bits combined into

predefined patterns of fixed length.

a. Character-oriented protocol

b. Bit-oriented protocol

c. a and b


4. The length of successive bits in

character-oriented protocol is

usually __________ bits.a. 2

b. 4

c. 8

d. 16

5. Indicates that the next character is

the first character of the text

a. ETX

b. STX

c. BSC

d. SDLC

6. Indicates that the next character is

the last character of the text

a. ETX

b. STX

c. BSC

d. SDLC

7. Character-oriented protocols are

sometimes called __________.

a. byte-oriented protocols

b. bit-oriented protocols

c. frame-oriented protocolsd. data-oriented protocols

8. Bit-oriented protocols are

__________ than character-oriented

protocols.

a. less efficient

b. more efficient

c. same efficiency

d. it depends

9. A discipline for serial-by-bit

information transfer over a datacommunications channel

a. Character-Oriented Protocols

b. Byte-Oriented Protocols

c. Frame-Oriented Protocols

d. Bit-Oriented Protocols

10. Most popular bit-oriented protocols

are:



a. BSC

b. SDLC and HDLC

c. BLAST

d. XMODEM and YMODEM

11. Relatively simple, character-oriented

protocols generally used on two-point networks using asynchronous

data and asynchronous modem

a. Synchronous Data-Link Protocols

b. Isochronous Data-Link Protocols

c. Asynchronous Data-Link

Protocols


12. The first file transfer protocol

developed by Ward Christiansen in

1979.

a. WMODEM

b. ZMODEM

c. YMODEM

d. XMODEM

13. A data-link control character that is

used to indicate the beginning of the

header

a. SOH

b. Sequence number

c. Information Field

d. STX14. An asynchronous data-link protocol

with information field which has a

maximum capacity of 1024 bytes.

a. XMODEM

b. YMODEM

c. ZMODEM

d. KERMIT

15. A data-link protocol where remote

stations can have more than one PC

or printed.a. Asynchronous Data-Link

Protocols

b. Bit-oriented protocol

c. Character-oriented protocols

d. Synchronous Data-Link

Protocols

16. A synchronous character-oriented

data-link protocol developed by IBM

a. Bisynchronous communications

b. Bisync

c. BSC

d. all of the above17. Indicates that the BCC was good

a. Positive Acknowledgment

b. Negative Acknowledgment

c. ARQ

d. NAK

18. An automatic request for re-

transmission

a. Positive Acknowledgment

b. Negative Acknowledgment

c. ARQ

d. ACK

19. Used to terminate blocks of data

except the final block

a. DLE SYN

b. DLE ITB

c. DLE ETB

d. DLE CRC

20. Used to terminate blocks of

transparent text other than the final

block when the end of intermittent

block is used for a block-terminatingcharacter

a. DLE SYN

b. DLE ITB

c. DLE ETB

d. DLE CRCs

SYNCHRONOUS DATA-LINK PROTOCOL

Reported by: Aguilar, Licarnette P.Bedonia, Sheila Marie V.

Maglalang, Jess Brian C.

Rocaverte, Dacely B.



1. What is the first link-layer protocol

based on synchronous, bit-oriented

operation?

a. Synchronous Data-Link Control

b. High-Level Data-Link Control

c. Link Access Procedured. IEEE 802.2

2. An address common to a number of

stations

a. Broadcast address

b. Station address

c. Group address

d. IP block

3. How many addresses are possible in

an address field?

a. 252

b. 256

c. 254

d. 248

4. It prevents the flag pattern from

occurring anywhere else in the

frame.

a. Flag bit

b. Zero insertion

c. Sequential Frame

d. Cyclic Redundancy Checking

5. The ending and beginning flag hasthe binary format __________.

a. 01111110

b. 10000000

c. 10000001

d. 0000110X

6. It is an eight-bit field that identifies

the type of frame being transmitted.

a. Flag field

b. Address field

c.

Control fieldd. Information field

7. The following are the frame formats

with SDLC except for?

a. Information

b. Supervisory

c. Unnumbered

d. Frame-check

8. Used for transmitting sequenced

information that must be

acknowledged by the destination

station.

a. Information

b. Supervisoryc. Unnumbered

d. Frame-check

9. With this frame format, an

information field is not allowed.

a. Information

b. Supervisory

c. Unnumbered

d. Frame-check

10. Identified by making bits b6 and b7 in

the control field both logic 1s.

a. Information

b. Supervisory

c. Unnumbered

d. Frame-check

11. Generating polynomial used by the

Frame Check Sequence Field.

a. x^7+x^5+x^4+x^2+1

b. x^16+x^12+x^5+1

c. x^16+x^13+x^10+5

d. x^9+x^6+x^3

12. SDLC loop operation operates in __________.

a. Full duplex

b. Simplex

c. Full/full duplex

d. Half-duplex

13. It is a subcommand used to isolate

open-loop continuity problems.

a. Wrap

b. Modified-Link Test

c.

Beacon Testd. Modified Link Test

14. Eight consecutive logic 0s sent by

the primary after the last frame

a. Go-ahead sequence

b. Turn-around sequence

c. Clear sequence

d. Last flag



15. Secondary stations cannot transmit

frames of their own until they

receive a frame with the

__________.

a. X bit set

b. F bit setc. P bit set

d. Y bit set

16. An SDLC operation that discusses

the occurrence of the flag bit

sequence

a. SDLC Transparency

b. SDLC Loop Configuration

c. SDLC Occurrence Sequence

d. SDLC Bit Sequence

17. A mechanism that inserts 0 in able

to provide more reliable frames

a. Zero Bit Insertion

b. Zero Bit Stuffing

c. a and b


18. Used to prematurely terminate an

SDLC frame

a. Message Reject

b. Message Reject

c. Message Abort

d. Message Cancel19. Superset of SDLC

a. SDLC-A

b. HDLC

c. a and b


20. What is the term when a station is

logically disconnected from the

network?

a. Normal Separate Mode

b.

Normal Disconnect Modec. Normal Disengage Mode

d. Normal Detach Mode

PUBLIC-SWITCHED DATA NETWORKS

Reported by: Abanag, Ma. Jessica Edfelie L.

Liwanagan, Lovely Erish S.

1. Used for making a standard

telephone call

a. Circuit-switching

b. Message-switchingc. Store-and-forward

d. Interconnect

2. Time required to establish a call

a. Real time

b. Setup time

c. Blocking

d. Short

3. After a call has been established,

information is transferred in

__________.

a. Public-Switched Data Network

b. Packets

c. Real time

d. Value added network

4. It is the inability to complete a call

because there are no facilities or

switching paths available between

the source and destination

locations.

a. Not transferred

b. Interconnectc. Hold-and-forward

d. Blocking

5. A circuit switch is a transparent

switch because it does nothing more

than __________ the source and

destination.

a. transfer

b. hold-and-forward

c. interconnect

d.

short 6. Message switching is a form of

__________ network.

a. packet-switching

b. store-and-forward

c. transactional switch

d. message-switching



7. In message switching, data are

__________ in real time.

a. not transferred

b. short

c. transferred

d. hold-and-forwarded 8. With message switching, blocking

__________ occur.

a. cannot

b. can

c. both a and b

d. all of the choices

9. Message switch is a __________.

a. packet

b. Public-Switched Data Network

c. Value Added Network

d. none of the choices

10. Data are divided into smaller

segments, called __________.

a. frames

b. bits

c. packets

d. segments

11. In packet switching, the hold time is

generally quite __________.

a. long

b. shortc. important

d. negligible

12. In packet switching, message

transfer is near __________.

a. real time

b. setup time

c. hold-and-forward

d. store-and-forward

13. Packet switching is sometimes called

__________ network.a. switcher switches

b. value added network

c. node-node communication link

d. hold-and-forward

14. A switched data communications

network designed for transferring of

data only.

a. Public-Switched Data Network

b. Packet Switching Network

c. Value Added Network


15. These are switching nodes that

connect only to other switchingnodes if some switching nodes are

already connected to end stations.

a. Tandem switching nodes

b. Real time nodes

c. Switchers switches

d. Both a and c

16. The combined concepts of Public

Switch Data Network

a. Value Added Network and

Circuit Switching

b. Packet Switching Network and

Circuit Switching

c. Value Added Network and

Packet Switching Network

d. Packet Switching Network and

Message Switching

17. A network which adds value to the

services or facilities provided by a

common carrier to provide new

types of communication services

a. Value Added Networkb. Transferred

c. Both a and c

d. None of the choices

18. It involves dividing data messages

into small bundles of information

and transmitting them through

communications network to their

intended destinations using

computer- controlled switches.

a.

Packet Switching Networkb. Value Added Network

c. Both a and c

d. None of the choices

19. Three common switching techniques

used with public data networks

a. Circuit Switching, Message

Switching, Packet Switching



b. Tandem Switching Nodes, Packet

Switching Network,

Transactional Switch

c. Circuit Switching, Packet

Switching Network,

Transactional Switchd. Packet Switching, Message

Switching, Packet Switching

Network

20. __________ generally carry

multiplexed data.

a. Frames

b. Node-Node Communication

Link

c. Communication Link

d. All of the Choices

CCITT X.25 USER-TO-NETWORK INTERFACE

PROTOCOL

Reported by: Candido, Averille John R.

Dimaculangan, Jan Darryl C.

1. ISO is to seven-layer, X.25 is to three

layer namely:

a. Physical, session, transportb. Application, session, datalink

c. Network, application, transport

d. Physical, data link, network

2. In circuit switching, path is

established for entire message,

while in Packet Switching:

a. Route established for each

packet

b. Links are established in every

layerc. Route are connected to every

layer


3. In Message Switching, messages are

stored, while in Packet Switching

a. Messages are not stored

b. Messages are held for a short

time

c. Messages are stored

permanently


4. In circuit switching,a. Network responsible for lost

messages

b. Network may be responsible for

each packet but not for the

entire messages

c. User responsible for message-

loss protection


5. Packet Switching is the same as

__________ when it comes to

overhead bits

a. Circuit Switching

b. Message Switching

c. Current Switching

d. Equipment Switching

6. ANSI 3.66 and HDLC were selected

for the __________ layer.

a. Physical

b. Data-link

c. Network

d. Transport7. LAPB provides for a two-way

__________ communications

between DTE and DCE.

a. Simplex

b. Half duplex

c. Full duplex

d. Full-full

8. __________ command is used to

transmit packets.

a.

DISCb. Information

c. Send

d. DM

9. The network layer specifies three

switching services namely:

a. Permanent virtual call,

temporary virtual call, datalink



b. Permanent virtual call, virtual

call, datagram

c. Instagram, permanent call, call

waiting

d. Packet, circuit, message

switching10. A Virtual Call is__________

arrangement.

a. One-one

b. One-many

c. Many-many


11. If messages will fit into single packet

where Datagram is somewhat

reliable, it is called:

a. Single-message per segment

protocol

b. Single-packet per segment

protocol

c. Multi-packet per segment

protocol


12. Two packet formats used in X.25

a. Send and receive packet

b. Front to back packet

c. Call request and data transfer

packetd. None of the above

13. This field identifies the number of

digits that appear in the called

address field

a. Calling address length

b. Facilities field

c. User data field


14. This field identifies the number of

eight-bit octet present.a. Rice field

b. Protocol Identifier field

c. Octomerical Field

d. Facilities Length Field

15. Deals with network architecture,

transmission, signaling, maintenance

a. X.44

b. X.1 through X.39

c. X.40 through X.199


16. A data transfer packet (DTP) is

similar to call request packet (CRP)

except that:a. DTP has considerably less

overhead and can

accommodate a much larger

user data field.

b. CRP has considerably less

overhead and can accommodate

a much larger user data field

c. Both a and b


17. The two packet sequence field

a. Call request and data transfer

b. Send packet and receive packet

c. Circuit and Packet


18. CCITT stands for:

a. Commission on Communications

International for Telephony and

Telegraphy.

b. Committee Consultative


Telegraphyc. Center for Communications


Telegraphy.

d. None of the above.

19. ______ is logically equivalent to

two-point dedicated private line.

a. Datagram

b. Virtual call

c. Permanent virtual call

d.

None of the above20. The most efficient service offered in

packet switching

a. Datagram

b. Permanent virtual call

c. Virtual call




INTEGRATED SERVICE DIGITAL NETWORK

Reported by: Guillomas, Hernan Jr. A.

Royo, Kristel Nova M.

1. It is a proposed network that isintended to provide worldwide

telecommunications support of

voice, data, video and facsimile

information within the same

network.

a. PSDN

b. X.25

c. ISDN

d. SDLC

2. In essence, the __________ is the

integration of a wide range of

services into a single multipurpose

network.

a. PSDN

b. X.25

c. ISDN

d. SDLC

3. A network that proposes to

interconnect an unlimited number

of independent users through a

common communications network.a. PSDN

b. X.25

c. ISDN

d. SDLC

4. The 64-kbps digital connection is the

basic building block of __________.

a. PSDN

b. X.25

c. ISDN

d.

SDLC5. It is called the picture or graphical

signal.

a. Facsimile

b. Digital

c. Analog


6. Which is not a key objective of

developing a worldwide ISDN

system?

a. System standardization

b. Multiplexed support

c. Addressing cost-related tariffsd. None of the above

7. Because of the obvious complexity

of ISDN, it requires __________

a. Standard interface connection

b. Control system to facilitate

multiplexing and demultiplexing

data

c. Usage of variety of protocols and

applications

d. Nothing

8. It is a key objective of ISDN that

ensure universal access to the

network.

a. Achieving transparency

b. Migration

c. System standardization

d. Variety of configurations

9. A key objective that provides a

private-line(leased) and switched

services

a. Multiplexed supportb. System standardization

c. Variety of configurations

d. Separating functions

10. It allows the customers to use a

variety of protocols and

applications.

a. Achieving transparency

b. System standardization


d.

Separating functions11. It provides a service to low-capacity

personal subscribers as well as to

large companies

a. Multiplexed support

b. System standardization


d. Separating functions



12. It is a channel that is used for

carrying signalling information and

for exchanging network control

information.

a. D channel

b. B channelc. H channel

d. C channel

13. It is sometimes called the basic rate

interface

a. 23B + D

b. 2B + D

c. 3B + D

d. 32B + D

14. It provides multiple 64kbps channels

intended to be used by the higher-

volume subscribers to the network.

a. Basic rate interface

b. Access network

c. Primary rate interface

d. ISDN switch

15. It is also called as primary service.

a. Basic rate interface

b. Access network

c. Primary rate interface

d. ISDN switch

16. An __________ routes data to anoutgoing channel or central office

users.

a. Line termination

b. Network termination

c. Reference point

d. Exchange termination

17. Broadband network termination is

a. Broadband interface

b. Broadband node*

c.

Broadband terminald. Broadband network

18. The __________ data rates are used

for full-motion video transmission

a. H21 and H26

b. H26 and H22

c. H24 and H25

d. H21 and H22

19. A data rate that is intended for bulk

data transfer.

a. H21

b. H22

c. H23

d. H420. The broadband distant terminal is

responsible for __________.

a. Electrical to optical conversion

b. Multiplexing of peripherals

c. Maintenance of subscriber loop

system

d. All of the above

ASYNCHRONOUS TRANSFER MODE

Reported by: Ganalon, Kevin Ric L.

Mediana, Malcolm C.

a. It was developed in the 1980’s by

the ITU-T as part of BISDN.

a. ATM

b. ISDN

c. TDM

d. PLM

b. Cell size for ATM.a. 51

b. 52

c. 53

d. 54

3. Number of bytes for header in ATM.

a. 4

b. 5

c. 6

d. 7

4.

Number of bytes for payload inATM.

a. 46

b. 47

c. 48

d. 49

5. Exact year of development of ATM.

a. 1989



b. 1988

c. 1987

d. 1986

6. ATM breaks all traffic into 53-Byte

cells because

a. 53-Byte cells are the ideal sizefor the voice communication

b. 53-Byte cells are the ideal size

for data communication

c. 53-Byte cells are the ideal size

for circuit switching

d. 53-Byte cells are the

compromised size for both voice

and data communication

7. What gives ATM network the ability

to operate at different data rates

and why?

a. Its short, fixed length cells:

Allows the prediction of the size

of buffers to be used.

b. Its short, fixed length cells:

Enables the cells to be

transported via different routes.

c. Its short, fixed length cells: Short

delays for voice traffic.

d. It’s short, 5-Byte header: Less

delay for routing the cells.8. Why is ATM the goal for future

networking?

a. It is efficient for data transfer.

b. It's the only technology suitable

for transmission of digital

television.

c. It allows the integration of

voice, data and video into one

network.

d.

It creates an error free network.9. Which of the following is done in the

physical layer of the ATM network?

a. Cell multiplexing and

demultiplexing

b. Generic flow control

c. Transmission frame

generation/recovery

d. Monitoring of the user

information field for bit errors

and possible corrective actions

10. ATM is said to be a connection

oriented technology. What does this

mean and why is it necessary?a. Cells travel through the same

path to the receiver. By this,

cells do not have to be

rearranged.

b. Cells travel through different

paths. Therefore cells can reach

the receiver faster.

c. A path is reserved exclusively for

one user. Arrangement of cells is

not necessary.

d. Cells are transmitted using fiber

optic cables. Cells would be less

susceptible to errors.

11. Which of the following is not the

benefit of an ATM LAN?

a. Better performance concerning

with delays

b. Very high aggregate throughput

c. Interconnecting existing LANs

d. Simpler control and network

management12. What advantage does ATM have

over STM?

a. Unlike ATM, time slots provided

by STM for a particular user

cannot be grabbed by another

user.

b. It is cheaper to implement.

c. ATM is suitable for real time

traffic but not ATM

d.

Time slots for STM occur atregular intervals.

13. A __________ is defined as a small,

fixed-size block of information.

a. Frame

b. Packet

c. Cell




14. The ATM standard defines

__________ layers.

a. two

b. three

c. four

d. five15. __________ eliminates the varying

delay times associated with

different-size packets.

a. X.25

b. Frame Relay

c. ATM

d. all of the above

16. A(n) __________ is the interface

between a user and an ATM switch.

a. UNI

b. NNI

c. NNN


17. __________ is the interface

between two ATM switches.

a. UNI

b. NNI

c. NNN


18. In ATM, the __________ layer

accepts transmissions from upper-layer services and maps them into

ATM cells.

a. physical

b. ATM

c. AAL



provides routing, traffic

management, switching, and

multiplexing services.a. physical

b. ATM

c. AAL



defines the transmission medium,

bit transmission, encoding, and

electrical-to-optical transformation.

a. physical

b. ATM layer

c. AAL


ETHERNET

Reported by: Ferranco, John Eric B.

Fortuno, Romina R.

Moral, Vincent Miller R.

1. Commonly known as “fast Ethernet”

a. 10Base-T

b. 10Base-5

c. 100Base-FL

d. 100Base-T

2. Approximate propagation velocity

along the cable in 10Base-5

a. 3x10^8 m/s

b. 2x10^8 m/s

c. 2.5x10^8 m/s

d. 1.2x10^8 m/s

3. Sometimes called “thicknet”

a. 10Base-2b. 10Base-3

c. 10Base-4

d. 10Base-5

4. Transmission media used by 10Base-

2

a. RG-11

b. RG-22

c. RG-58

d. RG-25

5.

Another name for 10Base-2a. thicknet

b. bagnet

c. cheapernet

d. mahalnet

6. Maximum distance between two

nodes in 10Base-5

a. 1 km



b. 1.5 km

c. 2 km

d. 2.5 km

7. Most popular 10-Mbps Ethernet

a. 10Base-2

b. 10Base-FLc. 10Base-5

d. 10Base-T

8. In 10Base-FL, “FL” stands for

__________.

a. fiber link

b. first link

c. flat link

d. flipped link

9. Most common 100-Mbps Ethernet

standard

a. 100Base-T4

b. 100Base-TX

c. 100Base-FL

d. 100Broad-T

10. Physical topology used in 100Base-

TX

a. mesh

b. bus

c. star

d. tree

11. Two most popular frame formatsa. IEEE 802.3 & Ethernet I

b. IEEE 803.3 & Ethernet II

c. IEEE 802.2 with Snap & DIX

1.0

d. Ethernet II and IEEE 802.3

12. LLC stands for:

a. Link to Link Control

b. Logical Link Control

c. Linked Logic Control

d.

Lagpak nang Lagpak saComms

13. Also called vampire tap

a. AUI

b. MAU

c. MIAU

d. MAUI

14. Original Ethernet designed by

Metcalfe and Boggs

a. Alto Aloha Network

b. Hawaiian Network

c. Cisco Network

d. Drug Network15. IEEE standard used to define full-

duplex Ethernet operation

a. 802.3x

b. 802.3y

c. 802.3z

d. 802.3 u

16. Consists of 8 bytes of alternating 1s

and 0s; Used to establish clock

synchronization

a. FCS field

b. Start of Frame delimiter

c. Preamble

d. Source Address

17. Field used for error correction

a. Preamble

b. FCS field

c. rice field

d. football field

18. Replaced the type field in Ethernet

frame

a. LLC fieldb. Length field

c. EOF delimiter

d. Start field

19. Ethernet II frame field that contains

the information

a. Length field

b. Information field

c. Data field

d. Start field

20. IEEE standard which defined the1000-Mbps Ethernet

a. 802.3x

b. 802.2x

c. 803.2z

d. 802.3z

Data Communications Problems

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