Peering ArchitectureIETF-63 VoIP Peering BOF

Sohel Khan, Sprint, TR&DAugust 4, 2005

Copyright © Sprint 2005. All rights reserved.

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Peering Requirement

• Security and Policy• Integrity• Efficiency• Reliability• Scalability• Harmonious Interoperability• Regulatory• Accounting

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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The major Issue

• State and Cost– Where the state be deployed?– What kinds of state should the network have?– What are the impacts of state?– What is the cost of media forwarding circuitry?– What is the cost of signaling infrastructure?– Security features– SIP optimization– Transcoding– Regulatory implementation

We believe that above depends on the way you deploy peering elements (PEs)

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Conceptual Deployment Scenarios

We illustrate four scenarios– Composed– Semi-Composed– Centralized (Non-IMS, IMS NNI, IMS UNI)– Distributed

• Our objective is to generate discussion in IETF community

• draft-sohel-sipping-s-bc-concept-arch-00.txt• PTSC-SAC-2005-213, ATIS-PTSC, June, 2005

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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IP Phone

IP Phone

Provider B

Provider A

PSTN PSTN

MG MGSS7

SS7

Wireless

Wireless

Reference Diagram

SF: Signaling FunctionMF: Media FunctionRF: Routing FunctionOF: O&M Function

SF SF

MF MF

RF RF

Ref. Functions

SF SIP Proxy, B2BUA, Session Admission Control (SAC), SIP Interoperability, SIP DoS protection, SIP Topology Hiding (THIG), and SIP security, privacy and encryption

MF VPN mediation, traffic engineering, policy enforcement, rate shaping, bandwith broker,

bandwidth theft protection, data integrity, transcoding, RTP translator, Network Address

Translation (NAT), and media security, privacy and encryption.

RF Routing protocol harmonization

OF CALEA implementation; accounting, billing and operational data mediation

OF OF

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Oth

er IP N

etwo

rks

AS

P-

Mw

Mw

Mw/Mk/Mm

Mr

Mi

Mp MnGq

Dx

Sh

Rf/Ro

PS

TN

/ISD

N

Ie

Mi

Oth

er IP n

etwo

rks

UE

Mg

Mj

Gm

ISC Cx

Dh

Ic

Rr/Ro

Cx

Ib

Ia

Id

PS

TN

If

PDF

MGCF

I-CSCF

BGCF

HSS

S-CSCF

MRFC

Mw

SLF

Charging Function

SGFSGW

IWF

I-BGF

RACS

AS

IBCFSEG

NASS

IMS functionsETSI TISPAN extensions

IP transport (access and core)

MRFPA-BGF T-MGFMGW

P-CSCF

ETSI TISPAN NGN Functional Architecture and Peering Elements

SF

MF + RF

SF

MF + RFOF Functions not shown

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Wireless

Bearer (RTP/IP)

Signal (SIP)

Conceptual Architecture Composed PE

MG: Media GatewayMGC: Media Gateway ControllerLD: Long Distance

SBC

IP Phone

IP Phone

PSTN

MG MGSS7

SS7

SBC

SBC SBC

Wireless

3rd Party IP Network

MF

RF

Session Border Controller (SBC)

PSTN

Composed architecture integratesControl, Bearer, and Routing planesin same device.Risk: N2 connectivity, cost, bottleneck, hot-potato route

OF

SF

CSCF

Proxy

MGCF

CSCF

Proxy

MGCF

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Conceptual Architecture: Semi-Composed PE

SFIP Phone

IP Phone

PSTN PSTN

MG MGSS7

SS7

Wireless

Wireless

3rd Party IP Network

SF

SF SF

MPLS Switch/Media Relay

SF

MF

RF

H.248/SIP

This architecture splits the Control and Bearer + Routing planes in separate devices.This is a one-to-one model

Bearer (RTP/IP)

Signal (SIP)

MG: Media GatewayMGC: Media Gateway ControllerLD: Long Distance

Edge-Proxy/CSCF, PDF,…

Security + Policy

Media Relay/E-LSRSecurity + Policy

Routing

CSCF

MF + RF

Media and Signal do need to flow thesame network.OF functions distributed across entities

Proxy

MGCF

CSCF

Proxy

MGCF

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Conceptual Architecture: Centralized (Non-IMS) NNI PE

IP Phone

IP Phone

SprintVoIPOther

VoIP

PSTN PSTN

MG MGSS7

SS7

Wireless

Wireless

3rd Party IP Network

SF

PSTN PSTN

Media Relay/MPLS Switch

MGCFSF MGCF

SF

MF

RF

MF

RF

MGCF+SFSecurity + Policy

Media Relay/E-LSRSecurity + Policy

Routing

Media Relay/E-LSRSecurity + Policy

Routing

Control plane of SBC integrates with MGC functions, Bearer + Routing planes integrate with edge routers. One-to-many model

ENUMENUM

OF functions distributed across entities

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Conceptual Architecture: Centralized (IMS) NNI PE

IP Phone

IP Phone

SprintVoIPOther

VoIP

PSTN PSTN

MG MGSS7

SS7

Wireless

Wireless

3rd Party IP Network

PSTN PSTN

Media Relay/MPLS Switch

SF

MF

RF

MF

RF

IBCF+I-CSCF+ SFSecurity + Policy

Media Relay/E-LSRSecurity + Policy

Routing

Media Relay/E-LSRSecurity + Policy

Routing

Control plane of SBC integrates with CSCF, Bearer + Routing planes integrate with edge routers. One-to-many model

ENUMENUM

SF CSCFBGCFCSCF SFBGCF

OF functions distributed across entities

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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PDF + P-CSCF

S-CSCF

I-CSCF

SF

PCS tower

PCS tower

PCS tower

MF + RF

OF functions distributed across entities

Conceptual Architecture: Centralized (IMS) UNI PE

A-BGF

Sohel Khan, Sprint--TR&D. Copyright © Sprint 2005.

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Conceptual Architecture: Distributed NNI PE

IP Phone

IP Phone

SprintVoIPOther

VoIP

PSTN PSTN

MG MGSS7

SS7

Wireless

Wireless

3rd Party IP Network

PSTN PSTN

Media Relay/MPLS Switch

SF+ CSCF+ MGCF

SF

SF+RF+MF RF+MF

SF+ CSCF + MGCF Security + Policy

Media Relay/E-LSRSecurity + Policy

RoutingSIP awareFirewall

This model distributes Control, Bearer, and Routing plane functions in different devices across the network

SF+ CSCF+ MGCF

ENUMENUM

RF+MFSF+RF+MF

OF functions distributed across entities