3G All IP Network 1 Outline Mobile Technology Evolution GPRS - - PowerPoint PPT Presentation

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3G All IP Network

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Outline

Mobile Technology Evolution GPRS Overview 3GPP UMTS System (Release 99) Introduction to VoIP Technologies

• H.323
• SIP
• MGCP/MEGACO
• SIGTRAN
• Softswitch

3GPP All IP Network

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Mobile Technology Evolution

1G – Analog System

• AMPS (Advanced Mobile Phone System) : 中華電信090系統

2G – Digital System

• GSM (Global System for Mobile Communication)

900MHz and 1.8GHz (DCS1800) TDMA and FDMA Technologies 9.6K bps Data Rate (Shore Message Service; SMS) 歐亞160 Countries, 全球55%市場, 約5億個用戶

• CDMA (Code Division Multiple Access)

IS-95: Data Rate 14.4K bps (cdmaOne) IS-95B: Data Rate 64 Kbps Qualcom 亞太北美市場, 約7,500萬用戶

• D-AMPS

又稱IS-136

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2.5G

GSM System

• High Speed Circuit Switch Data (HSCSD)

Up to 115.2 Kbps

• General Packet Radio Service (GPRS)

Up to 171.2 Kbps

• Enhanced Data rates for GSM Evolution (EDGE)

改變調變技術 up to 384 Kbps (Also considered as 3G technology) D-AMPS EDGE

cdma System

• cdma 1x

Up to 144 Kbps Korea

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GPRS System

Packet Switching Technology Based on GSM Cellular Network High Data Speed

• 21.4 Kbps per Time Slot (channel)
• Up to 8 Time Slots

GPRS

External Data Network

PSTN

HLR SGSN GGSN Gb Gn Gi GSM

PCU

BSS

Gateway MSC/VLR Visited MSC/VLR

Physical Channel for Data Transmission

• Assigned on Demand
• Can Be Shared with Other Users

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SGSN and GGSN

IP based Network

SGSN GGSN

HLR

Serving GPRS Support Node

. Mobility Management (Location Update, Paging etc.) . Access Control & Security (Authentication, Ciphering) . BSS Queue Management . GSM Circuit-Switched Interactions . Operation Data, such as Billing Info.

Gateway GPRS Support Node

. Interworking between PDN and GPRS PLMN . Packet Screening . Routing Tables about Attached GPRS Subscribers . Address Mapping . PDU Tunneling . Operation Data, such as Billing Info.

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GPRS MM/SM

Mobility Management

• Attach
• Detach
• Security
• Routing Area Update

Session Management

• PDP Context Activation
• PDP Context Deactivation
• PDP Context Modification

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3G

IMT-2000

• Year 2000 Ready
• Operate at 2000 MHz
• Provide 2000K bps Data Rate

3G Data Rate 要求

• Vehicular -- 144 Kbps
• Pedestrian --- 384 Kbps
• Indoor --- 2Mbps

Three Important 3G Technologies Standards

• W-CDMA (Wideband CDMA) (歐日系統)

GSM/GPRS/EDGE W-CDMA

• cdma2000 (北美系統)
• TD-SCDMA (Time Division Synchronize CDMA) (大陸系統)

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From 2G to 3G

From Voice Service to Rich, Interactive Multimedia-based Personal Communication Service Permanent Network Connection with High Data Rate

• 384 Kbps to 2 Mbps
• Mobile Aaccess to High-quality Video, Audio, Graphics and

Multimedia as Fixed Internet

Massive Increase in Network Capacity

• To Support Billions of Subscribers

Global Roaming

• To Use Single Terminal to Access Identical Services All Around

the World

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3GPP UMTS System

Node B Node B Node B Node B RNC RNC Iub Iur UTRAN USIM ME UE Cu 3G

MSC/VLR 3G SGSN

GMSC GGSN HLR External Networks

PLMN, PSTN, ISDN,...

Internet

Core Network Uu Iu

Iu-PS Gn Gi Gr Gc D D

System Architecture of 3GPP Release 99

Gs Iu-PS Iu-CS Iu-CS

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VoIP Protocols

H.323

SIP (Session Initiation Protocol) MGCP (Media Gateway Control Protocol) MEGACO (Media Gateway Control Protocol) SIGTRAN (Signaling Transport) Softswitch

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What is H.323

The H.323 standard provides audio, video and data communications across IP-based networks. H.323 is an umbrella recommendation from ITU, which was approved in 1996.

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RAS Channel

• 1. ARQ (alias address/bandwidth)
• 2. ACF (call signaling channel address/bandwidth)

5. ARQ 6. ACF

• 3. Setup

Q.931 Call Signaling Channel

• 4. Call Proceeding

Gatekeeper Terminal B

Terminal A

• 7. Alerting
• 8. Connect (H.245 Address)

H.245 Control Channel Capability Exchange OpenLogicalChannel OpenLogicChannelACK Logical Channel (RTP Stream)

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What is SIP

Developed in IETF

• Proposed standard RFC 2543, February 1999
• Current standard: RFC 3261

Main functions

• Invite users to sessions

Find the user’s current location, match with their capabilities and preferences

• Modification of sessions
• Termination of sessions

Text-based Encoding

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SIP Architecture

User Agent Client (Calling Party) Proxy Server Proxy Server Proxy Server Redirect Server Location Server SIP Request SIP Response Media Stream User Agent Server (Called Party)

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Invitation for SIP Proxy Server

itri.org.tw

location server

BENZ

honda@AUDI

(5) AUDI (1) INVITE honda@itri.org.tw acer@csie.nctu.edu.tw

csie.nctu.edu.tw

BMW (2) honda (3) honda@AUDI (4) INVITE honda@AUDI (5) 200 OK (6) 200 OK (7) ACK honda@itri.org.tw (8) ACK honda@AUDI

RTP Stream

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Invitation for SIP Redirect Server

itri.org.tw

location server BENS AUDI

Honda@AUDI

acer@csie.nctu.edu.tw

csie.nctu.edu.tw

BMW (2) honda (3) honda@AUDI (4) 302 Moved temporarily

Contact: Honda@AUDI.itri.org.tw

(5) ACK Honda@itri.org.tw (1) INVITE Honda@itri.org.tw (6) INVITE Honda@AUDI.itri.org.tw (7) 200 OK (8) ACK Honda@AUDI.itri.org.tw

RTP Stream

18 Class 5 End Office Switch

The Telephone Network [1/2]

Circuit Switched Network

Intelligent Peripheral Signal Transfer Point Service Control Point Class 4 Tandem Switch Service Data Point + Transport Layer Control Layer SS7 Signaling ISUP Messages INAP/TCAP Messages

Reference: CCL/ITRI

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The Telephone Network [2/2]

5 Basic Components in Intelligent Networks

• SSP/Service Switching Point

switching, signaling, routing, service invocation

• STP/Service Transfer Point

signaling, routing

• SCP/Service Control Point

service logic execution

• SDP/Service Data Point

subscriber data storage, access

• IP/Intelligent Peripheral

resources such as customized voice announcement, voice recognition, DTMF digit collection

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Introduction to MGCP/MEGACO

A protocol for controlling media gateways Two components

• Media gateway provides conversion between audio

signals on telephone circuits and data packets carried

• ver IP networks.
• Call agent (Media gateway controller) handles the call

setup and release for media channels in a media gateway. Types of media gateway

• Trunking gateway to CO/switches
• Residential gateway to PSTN phones

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MGCP/MEGACO-based Architecture

Signaling (SS7) Gateway Trunking Gateway

Call Agent SCP

Residential Gateway

Internet

SS7 Network

STP

Trunking Gateway Trunking Gateway

CO Switch

Residential Gateway Residential Gateway

MGCP/MEGACO RTP SIGTRAN MGCP/MEGACO

PSTN

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SIGTRAN

IETF SIGTRAN (Signaling Transport) - for SS7 over IP

ISUP TCAP SCCP MAP MTP

OSI Layers Application Presentation Session Transport Network Data Link Physical

INAP

SS7 Protocol Stack

ISUP TCAP SCCP MAP

SCN Signaling Adaptation (SSA) Common Signaling Transport (CST)

IP INAP

SIGTRAN Protocol Stack

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Softswitch Overview [1/2]

Softswitch: Emulating Circuit Switching in Software

IN/SCP

PSTN Local Switch PSTN Local Switch STP SS7 Network

IP Network

RTP Streams MGC MGC MGC MGC Trunk Trunk Gateway Gateway Trunk Trunk Gateway Gateway SIP-T SG SG SG SG SIGTRAN MEGACO IP Phone IP Phone

Personalized VoIP Service System

Application Server Application Server

Reference: CCL/ITRI

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Softswitch Overview [2/2]

Softswitch Provides Open Layered Architecture

• Solutions in a proprietary box
• Expensive
• Little room for innovation

Circuit-Switched

Transport Hardware Call Control & Switching Services & Applications

P R O P R I E T A R Y

• Solutions are open standards-based
• Customers choose best-in-class products
• Open standards enable lower cost for innovation

Soft-Switched

Transport Hardware Softswitch Call Control Services, Applications & Features (Management, Provisioning and Back Office) Open Protocols APIs Open Protocols APIs

Open APIs for 3rd Party App develop. Best-in-class Access Devices. Scalable, Open Interfaces for Comm.

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Softswitch Architecture

SIP-T CO Switch STP SCP CO Switch STP SCP Signaling Layer Transport Layer IP Media Server RTP SIP-? SIP-TSI

Media Gateway Controller Trunking Gateway Signaling (SS7) Gateway Media Gateway Controller Residential Gateway

SIGTRAN RTP

SS7 TCAP

MGCP/ MEGACO Phones

ISUP/TCAP

App. Server MGCP/MEGACO

Reference: CCL/ITRI

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3GPP All IP Network

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All IP Architecture

Based on packet technologies and IP telephony for real time and non real time services An evolution from Release 99 specifications

• All IP core network should support release 99 CS

terminals

Radio Access Network (RAN)

• GERAN and UTRAN

Core Network

• Based on the evolution of GPRS

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3GPP All IP Network

RNC

Node B Node B MS

MS

SGSN

T-SGW

Internet

PSTN

MSC Server

GGSN

Legacy mobile signaling network

CSCF HSS MGW MGW

GMSC Server R-SGW

MAP MAP Mc Mc Gi Gi Nc Nb Iu_CS (control part) Mh Gr Gc Cx Mm Ms Gn Iu_PS Iu_CS (user traffic) Gi Mc

MGCF

Mg Gi Mr

MRF

Signaling (SS7 or IP based) Circuit Packet (user traffic / signaling) Call control function

Reference: CCL/ITRI

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Circuit-Switched Services

RNC

Node B Node B MS

MS

T-SGW

PSTN

MSC Server Legacy mobile signaling network

HSS MGW MGW

GMSC Server R-SGW

MAP MAP Mc Nc Nb Iu_CS (control part) Mh Gr Iu_CS (user traffic) Mc Signaling (SS7 or IP based) Circuit Packet (user traffic / signaling) Call control function

Reference: CCL/ITRI

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Packet-Switched Services

RNC

Node B Node B MS

MS

SGSN Internet GGSN HSS

Gi Gr Gc Gn Iu_PS Gi Signaling (SS7 or IP based) Circuit Packet (user traffic / signaling) Call control function

Reference: CCL/ITRI

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Real-Time PS Services

RNC

Node B Node B MS

MS

SGSN Internet GGSN

Legacy mobile signaling network

CSCF HSS

R-SGW

Gi Mh Gr Gc Cx Mm Ms Gn Iu_PS Gi Mg Gi Mr

MRF

Signaling (SS7 or IP based) Circuit Packet (user traffic / signaling) Call control function

Reference: CCL/ITRI

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Interworking with PSTN

RNC

Node B Node B MS

MS

SGSN

T-SGW

Internet

PSTN

GGSN

Legacy mobile signaling network

CSCF HSS MGW

R-SGW

Mc Gi Gi Mh Gr Gc Cx Mm Ms Gn Iu_PS Gi

MGCF

Mg Gi Mr

MRF

Signaling (SS7 or IP based) Circuit Packet (user traffic / signaling) Call control function

Reference: CCL/ITRI

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HSS

HSS (Home Subscriber Server) is the master database for a given user. Functionalities

• The HLR functionality required by the PS-Domain
• The circuit switched part of the HLR
• User control functions required by the IP multimedia

(IM) subsystem HSS

MSC Server GMSC Server SGSN GGSN R-SGW CSCF

D C Gr Gc Mh Cx

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CSCF [1/4]

Call State Control Function ICGW (Incoming Call Gateway)

• Acting as a first entry point to perform routing of incoming

calls

CCF (Call Control Function)

• Call setup/termination and call state/event management
• Application level registration handling

SPD (Serving Profile Database)

• Interacting with HSS to receive user profile information

AH (Address Handling)

• Mapping between alias address (e.g., E.164 number) and

transport address

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CSCF [2/4]

Proxy CSCF (P-CSCF) is the first contact point within IM CN subsystem.

• Its address is discovered by UEs following PDP

context activation procedure.

• Behaving like a Proxy server defined in RFC2543

P-CSCF Discovery

• Use of DHCP (Dynamic Host Configuration Protocol)
• Transfer the P-CSCF address with the PDP Context

Activation signaling to the UE

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CSCF [3/4]

Serving CSCF (S-CSCF) performs the session control service for the UE.

• Maintaining a session state as needed by the

network operator for support of the services

Registration

• Behaving as a Registrar as defined in RFC2543
• It accepts registration requests and makes its

information available through the location server (e.g., HSS).

Session Flow

• Interaction with service platform for support of

services

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Service Platform Interface

SIP Application Server CAMEL Service Environment

SIP+ OSA API Cx

IM SSF

SIP+

OSA Application Server S-CSCF OSA Service Capability Server (SCS) HSS

SIP+ CAP MAP

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CSCF [4/4]

Interrogating CSCF (I-CSCF) is the contact point within an operator’s network for all connections destined to

• a subscriber of that network operator, or
• a roaming subscriber currently located within that network
• perator’s service area.
• That is,I-CSCF is the first contact point within an operator’s

network for incoming call signaling.

Registration

• Assigning a Serving CSCF to a user performing SIP

registration

Session Flow

• Routing a SIP request received from another network

towards the S-CSCF(Serving Terminating UE)

• Obtaining the S-CSCF address from HSS

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MGCF & MGW

Media Gateway Control Function

• Being PSTN signaling termination point
• Performing protocol conversion between the legacy

(e.g., ISUP) and the All-IP network call control protocols

Media Gateway

• Being PSTN transport termination point
• Interfacing UTRAN over Iu

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MSC Server

Mainly comprising the call control and mobility control parts of a GSM/UMTS MSC Performing the connection control for media channels in a MGW MSC server + MGW = MSC

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MRF

Multimedia Resource Function

• Performing multi-party call and multi- media

conferencing functions

• The same function as an MCU in the H.323

network

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T-SGW & R-SGW

Transport Signaling Gateway Function

• Mapping call related signaling from PSTN/PLMN on

an IP bearer and sending it to the MGCF

• Providing PSTN/PLMN↔IP transport level address

mapping

Roaming Signaling Gateway Function

• Providing communication with a 2G/R99 MSC/VLR

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IM Subsystem

IP Multimedia (IM) CN subsystem

• Comprising all CN elements for provision of

multimedia services

The IM subsystem (IMS) utilizes the PS domain to transport multimedia signaling and bearer traffic. The IMS attempts to be conformant to IETF “Internet standards”.

• SIP (Session Initiation Protocol) has been selected

as the interfaces between the IM CN elements.

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Registration

UE GPRS IP MM CN Subsystem

• 1. Bearer Level Registration: GPRS
• 2. PDP Context Activation
• 3. P-CSCF Discovery
• 4. Application Level Registration

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Application Level Registration

I-CSCF P-CSCF

UE

HSS

• 1. Register

S-CSCF

Visited Network Home Network

• 2. Register
• 3. Cx-Query
• 3. Cx-Query Resp.
• 4. Cx-Select-Pull
• 4. Cx-Select-Pull Resp.
• 5. Register
• 6. Cx-Put
• 6. Cx-Put-Resp.
• 7. Cx-Pull
• 7. Cx-Pull-Resp.
• 8. 200 OK
• 9. 200 OK
• 10. 200 OK

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Call Setup Diagram

S-CSCF S-CSCF P-CSCF P-CSCF

GGSN GGSN SGSN SGSN Radio Access Network Radio Access Network

I-CSCF I-CSCF HSS HSS App. Server

3 1 2

Originating Home Network Visited/Home Network S-CSCF S-CSCF I-CSCF I-CSCF HSS HSS

5 6 7 8

Terminating Home Network

4

P-CSCF P-CSCF

GGSN GGSN SGSN SGSN Radio Access Network Radio Access Network 10 9

App. Server Originating Terminating Visited/Home Network

Reference: CCL/ITRI

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Session Flow Procedure

UE#1 S-CSCF#1 S-CSCF#2 UE#2 INVITE Ringing 200 OK ACK SDP Final SDP Reserv Success

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INVITE

P-CSCF P-CSCF

Home Network#1 INVITE+SDP INVITE + SDP

I-CSCF#2 HSS S-CSCF#2 S-CSCF#1

Home Network#2

UE#2

INVITE + SDP

Service Control

INVITE + SDP Location Query Response INVITE + SDP INVITE + SDP 100 trying 100 trying 100 trying 100 trying 100 trying 100 trying

Service Control

UE#1

Visited Network#1 Visited Network#2

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183 Session Progress + PRACK

P-CSCF P-CSCF UE#1

Home Network#1 Visited Network

I-CSCF#2 HSS S-CSCF#2 S-CSCF#1 UE#2

183 (SDP) 183 (SDP) 183 (SDP) 183 (SDP) 183 (SDP) 183 (SDP) PRACK (Final SDP) PRACK (Final SDP) PRACK (Final SDP) PRACK (Final SDP) 200 OK 200 OK 200 OK 200 OK

Authorize QoS Resource Authorize QoS Resource

200 OK PRACK (Final SDP) Home Network#2 Visited Network#2

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Reserv Success (COMET)

P-CSCF P-CSCF UE#1

Home Network#1 Visited Network COMET

I-CSCF#2 HSS S-CSCF#2 S-CSCF#1 UE#2

COMET COMET COMET COMET 200 OK 200 OK 200 OK 200 OK 200 OK Resource Reservation Resource Reservation Home Network#2 Visited Network#2

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Ring (180 Ringing) + 200 OK (Hang Up) + ACK

P-CSCF P-CSCF UE#1

Home Network#1 Visited Network

I-CSCF#2 HSS S-CSCF#2 S-CSCF#1 UE#2

Ring Ring Ring Ring Ring Ring

Ringback

200 OK 200 OK

Service Control

200 OK 200 OK

Service Control

ACK ACK ACK ACK ACK 200 OK 200 OK

Approval of QoS Commit Approval of QoS Commit

Home Network#2 Visited Network#2