wc cdg isdr technical arch options june2006 irt

8/12/2019 WC CDG ISDR Technical Arch Options June2006 IRT

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ISDR

Inter-Standard Data Roaming

Technical Architecture Options

Lokdeep Singh

[email protected]

June, 2006
mailto:[email protected]:[email protected]


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Agenda

ISDR requirements

GPRS Roaming Overview

Implementation options for ISDR

Worldcell Introduction

Q&A


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Inter-standard Data roaming requirements

VHEVirtual Home environment Seamless experience to the user and CDMA

operator Integrated device for voice and data both on CDMA and

GSM

Present GPRS network as an integrated single V-PDSN Support for MIP,SIP architecture

Billing and clearing using AAA

Use exiting CRX connectivity

Integrated Signaling GW for IS voice and Data GSM MAP to ANSI MAPVoice/SMS

GSM MAP to AAAData and SMS


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GPRS Data Roaming Architecture

G G S N

G G S N S G S N

S G S NMS

MS

GRX

B G

B G

InternetG W

G W

Home Network Visited Network

G W

G W

HL R

HL R MS C

VL R

MS C

VL R

SCCP

G G S N

G G S N

Private

PDN

Private

PDN

B G

B G

GPRS Support Nodes: SGSN and GGSN

SGSN: Mobility Management, Security Functions, Access Control, sets up Data Sessions etc.

GGSN: interface to external PDN (Packet Data Networks).

PDP (Packet Data Protocol)Context defines the logical association between a MS (Mobile Station) and PDN (Public Data Network) thatis set up via a GPRS network. The PDP Context defines aspects such as the Packet Protocol used, APN (Access Point Name), QoS,Access Level, etc.

GTP (GPRS Tunneling Protocol) Tunnelis set up between SGSN and GGSN for PDP Context. User data is transferred transparentlybetween the MS and the external PDN with encapsulation and tunneling: data packets are equipped with GPRS-specific protocolinformation and transferred between the MS and GGSN.

GRX- Similar to CRX in functionality. Packet Data transferred between Home Network and Roaming Partner Network is transferred viaGRX (GPRS Roaming Exchange).


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GRPS Data RoamingScenarios

MS connects via VSGSN and VGGSN

Subscriber is roaming and registers using SGSN in roamingpartner network.

The SGSN determines via DNS query (using APN) that thePDP context will be set up via GGSN on the same network.

GTP tunnel is set up between VSGSN and VGGSN on localGPRS IP backbone.

Typical setup when Local Internet Access is provided by theroaming partner to roaming subscribers.

G G S N

G G S N S G S N

S G S NMS

MSInternet G TP

GTPG W

G W

Visited Network

Internet

G G S N

G G S N S G S N

S G S N

MS

MS

GRX

B G

B G

G W

G W

Home Network Visited Network

B G

B G

GTP

GTP

MS connects via VSGSN and HGGSN

Subscriber is roaming and registers using SGSN in roamingpartner network.

The SGSN determines via DNS query (using APN) that thePDP context will be set up via GGSN on the subscribershome network.

The DNS query procedure may involve usage of root DNS(master GPRS DNS accessible via GRX), or DNS on thehome network.

GTP tunnel is set up between VSGSN and HGGSN viaGRX network(s).

Typical setup when roaming subscribers access DataServices provided by the Home Network (e.g. MMS, WAP,Intranet, etc).


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APN (Access Point Name) APNs are used to identify Access Points (AP) to PDNs.

The APN consists of both: Network IDreference to the Access Point within GPRS PLMN (fully qualified domain name)

E.g. gprs.worldcell.com

Operator IDpoints to a GPRS PLMN

Complete APN has the following format: .mnc.mcc.gprs E.g. gprs.worldcell.com.mnc004.mcc274.gprs

APNs are resolved by DNS to GGSN IP address. They are used to create logicalconnection between MS and PDN, with GTP tunnel between SGSN and GGSN.

The GPRS DNS system is private network and does not have any interaction with theInternets DNS system.

The APN is constructed by SGSN during PDP Context Activation procedure, it can beobtained from a number of sources: From the MS, APN is entered by the subscriber (or stored in phone memory);

the HLR as part of the subscriber profile; or

default SGSN data.


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Signaling voice

Signaling- Data

Signaling -Tunnel

GPRS Data Roaming


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Differences in CDMA Packet Data and GPRS

Function CDMA GPRS

Basic Internet Access Visited PDSN and PCF Visited GGSN and SGSN

Corporate Private Access Visited PCF and PDSN - Tunnel End point is HA Home GGSN- Visited SGSN

Tunnel End Point in corporate network

Network Selection MS Selects network with NAI user@realm MS selects network with APN

IP assignment IP assignment by HA IP assignment by AAA/DHCP/L2TP Server

L2 Routing GRE Tunnels BSC-PCF and PCF-PDSN GTP tunnels GGSN_SGSN and RNC-SGSN

Billing PDSN consolidates and sends to AAA server -RADIUS SGSN-GGSN send to CGF

Authentication Often without SIM/RUIM With SIM/USIM


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ISDR challenges and Issues

Multi-Mode combined voice/data devices

Lack of MIP support on most GPRS networks

Different Protocols for data roaming

GSM MAP for data session authentication. Radius for CDMA

data session authentication Billing is TAP based in GPRS, RADIUS based in CDMA

GTP tunnel in GPRS, GRE in CDMA for achieving MIP

Limited LNS resources in CDMA PDSN

Complex APN-NAI mapping Multiple NAIs in CDMA to support

multiple rate plans, multiple network properties

GPRS carriers do not have SID/NID/Cell ID for used in BSID

attribute


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ISDR Framework

Support for MIP and SIP.

Device independent MIP/SIP selection based on APN and MIP proxy

Additional GRX connectivity not mandatory

Map to Radius (AAA) authentication supported

IIF acts as a GSM HLR/HGGSN for the GSM Roaming network

IIF acts as a ANSI VLR/FA/V-PDSN/LCA for CDMA Carrier

Support for MIP Proxy when MIP not available on MS

Network

Authentication

Plane

Data

Authentication

and Bearer

TrafficPlane


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ISDR Architecture Options

1. MIP Always- MIP tunnel back to HA irrespective

device/GPRS NW MIP support MIP reverse tunnel back to HA in all cases

2. SIP with internet Offload at H-GGSN SIP session with public internet access using GGSN of GSM(Sponsor)

NW

3. End to End GTP Extend GTP back to CDMA PDSN.

4. SIP with L2TP- LNS Proxy


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Option 1>MIP Always- MIP proxy

MIP proxy functions as FA and MNThe GTP tunnel shown is actually between SGSN and GGSN

IIF is responsible for the MAP-RADIUS conversion and APN and NAI mapping

Worldcell ,Inc. Proprietary and Confidential


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MIP Always-MIP Proxy Call Flow


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Option 2 >SIP with Internet Access Only


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Option3>SIP with GGSN in CDMA PDSN

The GGSN@CDMA needs to have GTT from GSM network The GRX connection from (Sponsor) GSM network can be used


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Option 4> SIP with L2TP and LNS proxy

IIF can act as LCA and as well LNS proxy in cases where home

CDMA PDSN does not support L2TP or has IP related LNS limitation


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About WorldCell Global provider of communication services

Company now providing Managed WirelessServices Business on leading networks acrossEurope and Asia

US Government (DoD, DoS)

Licensed GSM operator in Iceland Viking Wireless

roaming agreements with over 245 networks

WorldCell RSB provides Roaming Services tomajor wireless operators, supporting multiple

technologies including GSM, CDMA, WiFi HQ in US; Offices in Germany, Iceland and Brazil


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End to End

MIP GPRS-

CDMA call

flow


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CDMA to CDMA Packet data roaming

Mobile IPCall Flows

wc cdg isdr technical arch options june2006 irt

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