general packet radio

8/3/2019 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.



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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


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.

general packet radio

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