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Transcript of General Packet Radio
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General Packet RadioService (GPRS)
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September 30, 2005 Girish Kumar Patnaik 2
Introduction Based on the existing GSM infrastructure Provide end-to-end packet-switched
services GPRS standard
Initialized by ETSI/SMG in 1994 The main set of GPRS specifications was
approved by SMG#25 in 1997.
Completed in 1999 GPRS core network is designed for GSM,
IS-136 , and 3G.
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Introduction New radio channels are defined. The allocation of these channels is flexible.
One ~ eight time slots Several active users can share a single time slot. The uplinks and the downlinks are allocated separately.
Radio resources can be shared dynamically betweenspeech and data services as a function of traffic loadand operator preferences
Various radio channel coding schemes 9 Kbps ~ 150 Kbps GPRS fast reservation to start packet transmission
with 0.5 ~ 1 second
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Introduction
GPRS security functionality is equivalent tothe existing GSM security.
By allowing information to be deliveredmore quickly and efficiently, GPRS is
relatively inexpensive mobile data servicecompared to SMS and Circuit-SwitchedData.
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GPRS Architecture MS, BSS, MSC/VLR, and HLR in the
existing GSM network are modified.
Two new network nodes in GPRS Serving GPRS Support node (SGSN)
GPRS Equivalent to the MSC
Gateway GPRS Support node (GGSN) Provides Interworking with external packet-
switched networks, and is connected with SGSNsvia an IP-based GPRS backbone network
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GPRS Architecture
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GPRS Transmission &Signaling Planes
Layered protocol structure The GPRS Transmission Plane
For User information transfer
For Associated control procedures e.g., flow control, error detection, error correction, and
error recovery.
The GPRS Signaling Plane For control and support of the transmission plane
functions
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GPRS Transmission Plane
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GPRS Signaling Plane
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GPRS-specific Protocols
The GPRS-specific protocols includeSNDCP, LLC, RLC, MAC, BSSGP,BSSAP+, and GTP.
PLL, RFL, GMM/SM, and MAP are GSM protocols.
TCAP, SCCP, and MTP are SS7 layers.
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The GPRS Relay Functions
In BSS
(MS:Um
SGSN:Gb) The relay function relays logicallink control (LLC) Packet Data Units (PDUs).
In SGSN
(BSS:Gb GGSN:Gn) The relay function relaysPacket Data Protocol (PDP) PDUs.
(External network MS) PDP PDUs are encapsulated
and decapsulated for routing. (From the SNDCP and from Gi interface) The relay
function adds sequence number to PDP PDUs.
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Mobility Management
Mobility Management (MM) finite state machine Exercised in both the SGSN and the MS. Three states in the state machine:
IDLE: MS is not known to GPRS. STANDBY: MS is attached to GPRS. MS is tracked by
the SGSN at the RA level.
READY: MS is tracked at the cell level. Packet dataunits can only be delivered in this state.
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Mobility Management (MM)
Context The MM context consists
MM state Other MM-related information Both in MS and SGSN
Note that a GPRS MS can be IMSI-attached and GPRS-attached
GPRS-attached only IMSI-attached only The IMSI attach is the same as that for a GSM MS.
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Mobility Management (MM)
Context In GPRS attach procedure
Step 1: Both the MM states in MS and theSGSN are moved to the READY state .
Step 2: An MM context is created in each of MS and SGSN.
Step 3: Authentication/Ciphering may be
performed. Step 4: A logical link is established between
MS and SGSN .
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Mobility Management StateMachine
T1 (Idle Ready): MS performGPRS attach.
T2 (Ready Idle): MS isdetached from the GPRS.
T3 (Standby Ready): MSsends a packet to SGSN.
T4 (Ready Standby): a Readytimer is timeout.
T5 (Standby Idle): whentracking of MS is lost.
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STANDBY States
MS is attached. Detect page for GPRS data or signaling No data transmission allowed May initiate GPRS detach procedure to back to Idle. Change to Ready when data or signaling is sent (page
response, PDP context activation...) May initiate activation or deactivation of PDP context Not inform the SGSN on a change of cell in the same
RA Perform GMM Routing Area update procedure Perform GPRS cell selection and re-selection locally
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READY States MS is attached or attaching.
Perform GPRS cell selection and re-selectionlocally or controlled by the network
Perform cell update, but if RA changed, perform RA update
BSSCP header of the data packet includeCGI+RAC+LAC May send and receive PDP PDUs.
NWK will not initiate GPRS pages for an MSin this state
Cs pages may be done via SGSN
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READY States Other futures:
May activate or deactivate PDP contexts
Move to Standby when Ready timer expires or force to Standby
Move to Idle after detach
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PDP (Packet Data Protocol) To create a data transmission path,
MS initiate PDP Context Activation
procedure. Two PDP states: ACTIVE or
INACTIVE . PDP context in ACTIVE state contains
mapping and routing information for packet transmission between MS and
GGSN. The PDP contexts stored in MS, HLR,
SGSN, and GGSN.
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PDP Context
A PDP context is created for each communicationsession.
An MS in STANDBY or READY MM state mayactivate a PDP context.
MS moves its PDP state from INACTIVE to ACTIVE.
TMSI is known to the GGSN The ACTIVE PDP context becomes INACTIVE when
the PDP context is deactivated.
When the MS is detached from GPRS, all PDP contextsare deactivated.
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QoS Profile
A QoS profile is maintained in the PDP context toindicate radio and network resources required for
data transmission. Each PDP context has an associated QoS that
negotiated during PDP context activation procedure.
QoS attributes includes
Precedence class, Delay class, Reliability class, Peak throughput class, Mean throughput class
Q S P fil
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QoS Profile Precedence Class:
Three transmission priority levels During congestion, the packets with lower priorities are
discarded
Delay Class: Four delay levels Delay classes 1-3 are less than 0.5 sec., 5 sec., 50 sec.,
respectively Delay class 4 supports bets effort transmission without
specifying the transfer speed constraints.
Reliability Class: Defines residual error rates for data loss, out-of-sequence
delivery, and corrupted data
Five reliability classes
QoS Profile
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QoS Profile
Peak Throughput Class: Specifies the expected maximum data transmission
rate. Nine classes, ranging from 8Kbps to 2,048Kbps
Mean Throughput Class: Specifies the average data transmission rate
19 classes, ranging from the best-effort to 111Kbps
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GPRS Network Nodes
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GPRS Mobile Station A GPRS MS consists of a mobile terminal (MT)and terminal equipment (TE).
MT is equipped with software for GPRS functionality inorder to establish links to the SGSN
TE provides automatic retransmission (ARQ) at the datalink layer to retransmit the error frames.
Three MS operation modes: Class-A mode of operation
Simultaneous Circuit-switched and Packet-switched
Class-B mode of operation Automatic choice but only one at a time
Class-C mode of operation Packet-switched data only
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GPRS Mobile Station To support GPRS mobility management
MS maintains MM and PDP contexts.
MSs access GPRS services SIM is GPRS-aware SIM
IMSI, P-TMSI, P-TMSI Signature, Roting Area (RA), CurrentCiphering Key (Kc), and Ciphering Key Sequence Number (CKSN) stored in the GPRS-aware SIM shall be used.
SIM is not GPRS-aware SIM P-TMSI, P-TMSI Signature, Routing Area, Kc, and CKSN are
stored in the ME.
Other parameters are stored in ME.
( )
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Base Station System (BSS) BTS provides new GPRS channel coding schemesthrough Channel Codec Unit (CCU). BSC forwards
Circuit-switched calls to MSC Packet-switched data to SGSN
Packet Control Unit (PCU) Responsible for the medium access control and radio link control layer functions, such as packet segmentation andreassembly, packet data traffic channel management (eg.access control, scheduling, and ARQ) and radio channelmanagement (eg. power control, congestion control, and
broadcast control information)
B S i S (BSS)
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Base Station System (BSS)
Serving GPRS Support
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Serving GPRS Support
Node (SGSN) SGSN connects BSS to GGSN
SGSN provides Ciphering Mobility Management
Charging Statistics collection
SGSN establishes an MM context for each MS
Mobility and security information SGSN establishes a PDP context at PDP context
activation.
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SGSN MM Context IMSI, P-TMSI, P-TMSI Signature,
MSISDN, IMEI MM state (Mobility Management state:
IDLE, STANDBY, or READY)
Routing Area Cell Identity Cell Identity age VLR Number
SGSN MM C t t
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SGSN MM Context New SGSN Address: The IP address of the new SGSN
where buffered and not sent N-PDUs should be forwardedto
Authentication, Ciphering Parameters, Current Cipheringkey Kc, and the selected ciphering algorithm Radio Access Classmark: MS radio access capabilities SGSN Classmark: MS network capabilities Mobile station Not Reachable for GPRS flag (MNRG)
(indicates whether activity from the MS shall be reported tothe HLR).
Non-GPRS Alert Flag (NGAF) (Indicates whether activityfrom the MS shall be reported to the MSC/VLR).
Paging Proceed Flag (PPF) (Indicates whether paging for
GPRS and non-GPRS services can be initiated).
SGSN PDP C t t
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SGSN PDP Context PDP context Identifier (Index of PDP context),
PDP type (e.g., X.25, PPP or IP), PDP address(e.g., an X.25 address), PDP state (Active, or Inactive).
Access Point Name (APN) to the external datanetwork.
QoS Profile Subscribed, QoS Profile Requested,QoS Profile Negotiated.
GGSN Address in Use Charging ID (Charging identifier, identifiescharging record generated by SGSN and GGSN)
Gateway GPRS Support
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Gateway GPRS Support
Node (GGSN) The GGSN is primarily provisioned by a router,
which supports traditional gateway functionality, Publishing Subscriber Addresses, Mapping Addresses,
Routing and Tunneling Packets, Screening Messages,and Counting Packets
GGSN may contain
DNS (Domain Name Server) DHCP (Dynamic Host Configuration Protocol)
GGSN maintains an activated PDP context .
An Activated PDP Context
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An Activated PDP Context
in GGSN IMSI PDP Type (e.g., X.25, PPP or IP), PDP Address Dynamic Address (Indicates whether PDP Address is static
or dynamic). QoS Profile Negotiated (The quality of service profile
negotiated).
SGSN Address (The IP address of the SGSN currentlyserving this MS).
Access Point Name (APN) (The APN requested by the MS).
MNRG (Indicates whether the MS is marked as notreachable for GPRS at the HLR).
Charging ID (Charging Identifier) (identifies charging
records generated by SGSN and GGSN).
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Home Location Register(HLR)
New fields in MS record are introduced inHLR. To map an MS to one or more GGSNs
Update the SGSN of the MS at attach anddetach
Store the fixed IP address and QoS profile for atransmission path
The GSN-Related
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The GSN Related
Information in HLR IMSI (the main reference key), MSISDN SGSN Number (The SS7 number of the SGSN currently
serving this MS) SGSN Address (The IP addresses of the SGSN currently
serving this MS).
MS Purged for GPRS MNRG (Indicates that the MM andPDP contexts of the MS are deleted from the SGSN). MNRG (indicates whether the MS is not reachable for GPRS
service). GGSN-list
(GSN number, optional IP address) related to the GGSN that shall becontacted when activity from the MS is detected and MNRG is set.
Each IMSI contains 0 or
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Each IMSI contains 0 or
More PDP Contexts in HLR PDP Context Identifier (Index of PDP Context) PDP Type (e.g., X.25, PPP, or IP) QoS Profile Subscribed (QoS Profile Subscribed is the
default level if a particular QoS profile is not requested)
VPLMN Address Allowed (Specifies if the MS isallowed to use the APN in the domain of the HPLMNonly, or additionally the APN in the domain of the
VPLMN). Access Point Name (A label according to DNS namingconventions describing the access point to the external
packet data network).
MSC/VLR
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MSC/VLR
MSC/VLR may store
IMSI SGSN Number SGSN number of GPRS-attached MSs that are
also IMSI-attached The MSC/VLR may contact SGSN
Request location information Paging for voice call.
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GPRS Interfaces
GPRS Architecture
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GPRS Architecture
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Um Interface (MS BSS) Um radio Interface: radio interface between
MS and BTS GPRS radio technology
Based on the GSM radio architecture New logical channel structure
To control signaling and traffic flow over the Umradio interface
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Radio Channel Structure The physical channel dedicated to packet
data traffic is called a packet data channel(PDCH ).
Different logical channels can occur on thesame PDCH.
Logical Channel Map
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Logical Channel Map
Packet Traffic Channels
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Packet Traffic Channels(PTCH)
Packet Data Traffic Channel (PDTCH) One PDTCH one physical channel Up to eight PDTCHs per MS
Packet Associated Control Channel (PACCH) Conveys power control, resource assignment and
reassignment information.
PACCH shares resources via PDTCHs. An MS currently involved in packet transfer can be
paged for circuit-switched services on PACCH.
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Logical Channels (PCCCH) Packet Common Control Channel (PCCCH)
Convey common control channel Whether PCCCH is allocated or not, CCCH can be
used to initiate a packet transfer. PCCCH includes PRACH, PPCH, PAGCH, PNCH.
Packet Random Access Channel (PRACH) (MS BTS) To initiate uplink transfer for data or signaling
Logical Channels (PCCCH)
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Logical Channels (PCCCH) Packet Paging Channel (PPCH) (BTS MS)
Page an MS for both circuit-switched and packet dataservices
Packet Access Grant Channel (PAGCH) (BTS MS)
Resource assignment in the packet transfer establishment phase
Packet Notification Channel (PNCH) (BTS MS) Used to send a Point-To-Multipoint Multicast (PTM-
M) notification for resource assignment.
PBCCH & PTCCH
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PBCCH & PTCCH
Packet Broadcast Control Channel (PBCCH) Broadcast system information specific for packet data
If PBCCH is not allocated, GSM BCCH can be usedfor broadcast.
Packet Timing Advance Control Channel(PTCCH) (BTS MS) Transmit a random access burst BSS estimates timing advance. BSS to transmit timing
advance information updates to MS.
Two Concepts for GPRS
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Channel Management Master-Slave
Master: at least one PDCH PCCCH: control signaling for initiating packet transfer.
Salves: Other PDCHs PDTCH: for user data transfer
PACCH: for dedicated signaling Capacity on Demand
The Allocation of capacity for GPRS is based on the
needs for actual packet transfers. The operator decides the allocation of physicalresources (i.e. PDCHs) for the GPRS traffic.
PCCCH and PBCCH are not necessary to exist.
Access and Assignment
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Phase
GPRS Uplink Packet
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Transfer
Um Protocol Layers
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y RF Layer (RFL)
Performs modulation/demodulation .
Physical Link Layer (PLL) Provides services for information transfer over a
physical channel.
Medium Access Control (MAC) MAC is responsible for channel access (scheduling,
queuing, contention resolution), PDCH multiplexing,and power control.
Radio Link Control(RLC) block segmentation and reassembly, buffering, and
retransmission with backward error correction.
Four GPRS Coding Schemes
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Four GPRS Coding Schemes
Gb Interface
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(MS BSS SGSN) The Gb interface allows many users to be multiplexed
over the same physical resource.
The Gb interface includes Physical Layer Layer 2
NS (Network Service; Frame Relay) BSSGP (Base Station System GPRS Protocol) Relay Function LLC (Logical Link Control)
Layer 3 SNDCP (SubNetwork Dependent Convergence Protocol) GMM SM (GPRS Mobility Management Session Management)
Network Service (NS)
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Network Service (NS) Physical layer (BBS SGSN) : frame relay link Each frame relay link supports one or more
Network Service Virtual Links (NS-VLs). To construct an end-to-end virtual path between BSS
and SGSN. The path is Network Service Virtual Connection (NS-
VC)
NS manages NS-VCs.
Network Service (NS)
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Network Service (NS)
Using NS-VCs, NS transports data from up-layered BSSGP Packet Data Units (PDUs).
The NS layer delivers encapsulated packets(SGSN BSS).
Load sharing to distribute the packet trafficamong the unblocked NS-VCs.
BSS GPRS Protocol(BSSGP)
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(BSSGP) BSSGP Virtual Connection (BVC) provides
communication path between BSSGP entities (i.e.,
BSS, SGSN). BVC is supported by NS-VCs. Each BVC transports BSSGP PDUs.
BSSGP provides the radio-related QoS andRouting Information required to transmit user data(BSS SGSN).
Three service models supported by BSSGP: BSSGP/RL service model GMM Model
NM Model
BSSGP/RL Service Model
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(1) BSSGP/RL service model In BSS, Relay function provides buffering and
parameter mapping between RLC/MAC andBSSGP.
In SGSN, BSSGP controls the transfer of LLCframes across the Gb interface.
PDU contains User information (an LLC packet) RLC/MAC-related information A QoS profile PDU lifetime
GPRS Mobility Management(GMM) S i M d l
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(GMM) Service Model
(2) GMM Model
BSSGP GMM service model performsmobility management functions betweenSGSN and BSS.
Examples of GMM service primitives provided by BSSGP are
PAGING SUSPEND RESUME
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The Network Management(NM) Ser ice Model
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(NM) Service Model Flow control message FLOW-
CONTROLBVC (FLOW-CONTROL-MS)sent from the BSS to the SGSN To control downlink transmission at the SGSN
Parameters: buffer size and the bucket leak rate PDU in the downlink is not transferred to
the MS before its lifetime expires PDU is deleted from the BVC downlink buffer This action is reported to SGSN.
Gn & Gp interfaces
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Both Gn and Gp interfaces utilizes the GPRSTunneling Protocol (GTP). Gn (SGSN GGSN) Gp (SGSN External GGSN)
Gp is the same as Gn except
Extra security functionality for internetwork communications over the Gp interface.
With GTP,
An SGSN may communicate with multiple GGSNs. A GGSN may connect to many SGSNs.
Gn & Gp interfaces
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In the transmission plane, GTP is supported by the Transmission Control Protocol (TCP) for connection-
oriented transmission
User Datagram Protocol (UDP) for connectionlesstransmission
GTP transmission uses a tunneling mechanism tocarry user data packets. Two-way, point-to-point path
Tunneling transfers encapsulate data between GSNs. GTP implements out-of-band signaling.
Gn & Gp interfaces
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In the signaling plane, GTP is supported byUDP.
A GTP tunnel is defined by the associatedPDP contexts in two GSN nodes, and isidentified with a tunnel ID.
GTP performs Path Management Tunnel Management Location Management Mobility Management
Path and Location
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Managements in GTP Path management
To detect failures occurring in the path Echo_Request and Response message pair
Location management If GGSN does not support SS7 MAP for communication with an HLR.
the interaction (GGSN HLR) is done indirectlythrough a specific GSN that performs GTP-MAP protocol conversation (usually through SGSN).
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GTP Tunnel Management Creating Tunnels Updating Tunnels Deleting Tunnels
GTP Tunnel Management:Creating Tunnel
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Creating Tunnel
GTP Tunnel Management:Activate PDP Context
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Activate PDP Context
GTP Tunnel Management:Updating Tunnel
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Updating Tunnel
GTP Tunnel Management:Deleting Tunnel
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Deleting Tunnel
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GTP Mobility Management GTP MM functions:
GPRS Attach GPRS Routing Area Update
Activation of PDP Contexts
GTP Mobility Management
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Gs Interface
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Connects the databases in the MSC/VLR and the SGSN, which does not involve user data transmission
Base Station System Application Part+(BSSAP+) implements the functionality for
the Gs interface BSSAP+ utilizes SS7 Signaling Connection
Control Part as the lower layer Protocol
Gs Interface
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BSSAP+ procedures coordinate the locationinformation of MSs that are both IMSI- and
GPRS-attached. BSSAP+ are used to convey some GSM
procedures via the SGSN. Paging Procedure Suspend Procedure
Resume Procedure Location Update Procedure
Gs Interface: Paging
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Procedure VLR can use GPRS to page MS for
MSC/VLR-based service. Class A or Class B MS can simultaneously
IMSI and GPRS-Attached.
It is not necessary to page an MS for bothGSM and GPRS services.
Reduce the overall paging load on the radiointerface
Gs Interface: PagingProcedure
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Step 1. VLR sends the GPRS_PAGING to theSGSN.
Step 2. SGSN checks if the MS is GPRS attachedand is known by SGSN. Yes: SGSN sends the Gb PAGING to the BSS.
Step 3. SGSN forwards the paging result back tothe VLR. If the MS does not respond, VLR or BSS retransmits
the paging message. The SGSN is not responsible for retransmission of the
message.
Gs Interface: SuspendProcedure
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To perform circuit-switched activity for a Class BMS (both IMSI- and GPRS-attached).
VLR uses the SUSPEND procedure to inform theSGSN to suspend the GPRS activities of the MS.
Gs Interface: ResumeProcedure
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VLR sends a RESUME message to theSGSN to resume the GPRS activity of theMS.
Gs Interface: LocationUpdate Procedure
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p A MS-initiated GPRS location update
Step 1. SGSN sendsGPRS_LOCATION_UPDATING_Request to VLR.
Step 2. The VLR Checks to determine if the IMSI is known. If IMSI is unknown, VLR retrieves the MM context of the
MS from the HLR. Success: VLR returns a
GPRS_LOCATION_UPDATING_Accept to SGSN.
Fail: SGSN informs the MS that the location update failed. SGSN does not hear from the VLR within a period T8-1 VLR replies with a GPRS_LOCATION_UPDATING_Reject to
SGSN
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Gi Interface
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GGSN Interworks with PSDN (Public Switched Data Network) PDN(Packet Data Network)
Gi: GGSN PSDN/PDN The interworking models to PSDN includes X.25 and
X.75. An MS is assigned an X.121 address. This address
dynamically or permanently assigned
The interworking models to PDN includes IP andPoint-to-point (PPP).
The IP address is statically assigned or dynamically allocatedwhen PDP context activation.
Gi Interface
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GPRS may Transparently access the Internet Non-transparently access the intranet and ISP.
In transparently access the Internet, IP address from the GPRS operators
addressing space This address is used on GPRS network. No authentication request at PDP context
activation Domain name services provided by the GPRS
Gi Interface
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In nontransparent access to an intranet or ISP,
IP address of an MS from the intranet/ISPaddress space At PDP context activation, the MS must be
authenticated by the intranet/ISP. DNS provided by the intranet/ISP
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GPRS Procedures GPRS Attach GPRS Detach PDP context procedure RA/LA Update
GPRS Attach Procedure
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GPRS Detach GPRS detach can be initiated by MS,
SGSN, or HLR. The different types of detach are:
IMSI detach GPRS detach
Combined GPRS / IMSI detach (MS-initiatedonly)
GPRS Detach: HLR-InitiatedDetach Procedure (Message Flow)
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PDP Context Procedures
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PDP Context Activation MS-initiated
Network-requested PDP Context Modification PDP Context Deactivation
SGSN-initiated MS-initiated
GGSN-initiated
MS-initiated PDP Context
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Activation Procedure
Network-Requested PDPContext Activation Procedure
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PDP Context Modification
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SGSN-initiated PDP ContextDeactivation
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MS-initiated PDP ContextDeactivation
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GGSN-initiated PDP ContextDeactivation
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The Combined RA/LA Update Procedure
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GPRS Billing
GPRS Charging Nodes
Charging information is collected by SGSNs and
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Charging information is collected by SGSNs andGGSNs.
In SGSN Radio resource usage by an MS.
In external/internal GGSNs
Network usage The charging of the visited GPRS is gathered and
sent to the home GPRS network.
The Charging Info in SGSN
Location information
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Location information The amount of data transmitted
The amount of time The amount of GPRS-related network resources.. The GPRS activity (e.g., MM) Note that the data volume counted is at SNDCP
(Sub-Network Dependent Convergence Protocol)
level in SGSN.
The Charging Info in GGSN
Th dd f th d ti ti d
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The addresses of the destination and source The amount of data delivered The period Note that the data volume counted is at the
GTP level in GGSN.
Types of Call DetailedRecords (CDRs)
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S-CDR for the radio usage by SGSN G-CDR for external data network usage by
GGSN
M-CDR for Mobility Management activity by SGSN
Fields in S-CDR
MO (M bil O i i d) d l
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MO (Mobile Originated) data volume MT (Mobile Terminated) data volume Location Information SMS MO SMS MT Associated QoS Record Duration
Fields in G-CDR
D ti ti Add
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Destination Address Source Address Data Received Data Sent Associated QoS Record Duration
The Generation of CDRs
Every CDR is associated with an active PDP
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Every CDR is associated with an active PDPcontext. A CDR is generated by the following criteria:
End-of-Call Accounting Schedule Time-of-Day Accounting Schedule Inter-SGSN routing area update
Charging for packet-switched is more difficult. The cost of measuring packet is large. Existing GSM billing system may not able to handle
GPRS real time CDR information. Charging gateway
Evolving from GSM to GPRS
Reusing the GSM infrastructure
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Reusing the GSM infrastructure Software-related cost
GPRS software is remotely downloaded to BTSs. Hardware cost
PCU-module to BSC, GGSN and SGSN
MS development Resolve the power consumption
Multiple time-slot transmission (much more power)
GSM Network ElementsImpact by GPRS
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GPRS Phase 1Implementation
Standard Packet Services Delivery
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Standard Packet Services Delivery CS-1 and CS-2 Channel Coding Scheme
Gn, Gb, Gp, Gs interfaces Flexible Radio Resource Allocation Classes B and C MSs GPRS Charging IP and X.25 interfaces to packet data network
Static and dynamic IP Address Allocation Anonymous Access Security
GPRS Phase 2Implementation
Enhanced QoS support in GPRS
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Enhanced QoS support in GPRS Unstructured octet stream GPRS PDP type Access to ISPs and Intranets GPRS Prepaid GPRS Advice of Charge Group Call
Point-to-multipoint services
Applications in GPRS
Specific Data Communication Requirement of C i
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p qCompanies: Traffic Management (Fleet Management, Vehicle
Tracking, Vehicle Control, Guidance) Monitoring Automation (Telemetry and Security)
Applications for Individual Users Entertainment (Games and Music) Location Information (Restaurants, Cinema, Hotels,
Parking) Commerce Transactions (Banking, Airlines, trains,
Online Shopping.)
Acknowledgement
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Slides obtained from home page of
Prof.Phone Lin Slides obtained from home page of
Prof.Gerald Q. Maguire Jr.