Nortel Confidential Information 1 Core network integration issues for inter- RAT, inter-SDO mobility...

1 Nortel Confidential Information

Core network integration issues for inter-RAT, inter-SDO mobility (HRPD – WiMax Focus)

Nortel


Harmonizing core network functionality

• Most SDOs have some form of an ‘All IP’ core network that incorporates IETF defined functional elements and protocols.

• However, each SDO defines their own ‘All IP’ architecture and procedures for how these IETF tools are utilized. Specifically, each SDO defines its own policy framework, AAA framework and mobility management solutions.

• Therefore, inter-working between radio access technologies that are defined by different SDOs requires a much broader scope than just mobility management alone.

• This contribution highlights the other topics that require consideration (policy, authentication) and it suggests four potential core network solutions.


Policy Frameworks

• Current releases of other SDOs with dynamic policy control (3GPP2 All-IP, TISPAN R1.0) use off-path signaling

• All new releases incl. WiMAX specify the ref. point to ASN/visited network to be:

• bearerless (provide IP flow information per individual AF session)

• out of band (Diameter-based)• off-path (WiMAX also allows

parallel option)

• Bearerless, off-path model is agreed at ITU-T level in Rec. Y.2111 for Policy Control of Next Generation Networks

WiMAX R1.5 PCC (draft)

3GPP2 evolved network architecture (draft)

TISPAN RACS R2 Architecture (draft)

AFAF

Rx (Tx)Gx/(Ty)

R3 R6SFMBS

SFMBS

R4

ASN

PCRF PCRF

C-PCEFC-PCEF

Anchor SFAA-PCEF

Anchor SFAA-PCEF

MSMS

HAHA

CSN

PolicyDistribution

Function

PolicyDistribution

Function

Serving SFA

PCC-R3

PCC-based AAA

AAA

OCS/OFCS

OCS/OFCS

Visited Network

eBSeBS serving

AGW

servingAGW LMA/HA

LMA/HA

AFAF

ATAT

Tx

anchorAGW

anchorAGW

implementation option

Home Network

U18 V-PCRF

V-PCRF

VAAAVAAA

H-PCRFH-PCRF

HAAAHAAA

U23 U20 U15 U16

NGN Access Network Provider NGN Connectivity Provider

AccessNode

AccessNode IP

Edge

IPEdge

A-RACFA-RACF

v-NASSv-NASS

SPDFSPDF

h-NASSh-NASS

CoreBorder Nd

CoreBorder Nd

AFAFSPDF

SPDF

UEUE

Ri’

Di Re

e4

Ds Ia

Gq’

Sources:•WiMAX PCC NWG Rel 1.5 (Unapproved draft, March 2007)•X50-2070514-030r8 Proposed text for X.P00xx-000 UMB Network Specification•Draft ETSI TS 182 019 V0.6.1; TISPAN; Resource and Admission Control Sub-system (RACS) Rel 2.0; (2007-05)


AAA Frameworks

EAP Method (EAP-TLS, EAP-AKA, EAP-MD5, etc..)

EAP

MS BTS GW Proxy AAA

AAA ProtocolEAP Transport

UDP / IPData Link Encap.

User Identity Alignment?

Authenticator

Authenticator Location?

Authenticator Location?

Which EAP methods?

Which EAP methods?

RADIUS, DIAMETER or Both?

RADIUS, DIAMETER or Both?

Is it EAP in both RATs?

Is it EAP in both RATs?

Single or Double EAP?

Single or Double EAP?

Common AAA server?

Common AAA server?


Core network integration for inter-RAT mobility models:

• Pair-wise coupling Model:• WiMAX integrated under HRPD architecture• HRPD integrated under WiMAX architecture

• IETF-based Common Core• Core elements meet both WiMax and 3GPP2 requirements

• 3GPP EPC Model:• WiMAX and HRPD integrated under 3GPP EPC architecture• EPC architecture has specified a number of non-3GPP interfaces

and protocols that can be leveraged for inter-working with EUTRAN and between other RATs.

• CAN• WiMAX and HRPD both integrated under CAN architecture. • CAN architecture has specified non-3GPP2 interfaces, but has yet

to define how policy, authentication and mobility will behave.


WiMAX

BTS RNC PDSN

IMS(CSCF)

AAA

HRPD

HA

BTS

PCRF

ASN GW

ASN

A10, A11

R6R3 AAA HA

CSN

PF

Staring Point (non-roaming)

Ty


WiMAX

BTS RNC PDSN

IMS(CSCF)

AAA

HRPD

HA

BTS

PCRFPF

ASN GW

ASN

A10, A11

R6

R3

AAA HA

CSN

PF

WiMax integrated into HRPD architecture (non-roaming)

Ty

R3/PCC

Tx/Rx?

Tx or Rx semantics?Tx or Rx semantics?

Authentication, credential and identity alignment

Authentication, credential and identity alignment

Migration to PMIPv6?

Migration to PMIPv6?

WiMax aligns to the HRPD core network.


WiMAX

BTS RNC PDSN

HRPD

BTS ASN GW

ASN

A10, A11

R6 R3 AAA HA

CSN

PF

WiMax integrated into HRPD architecture (non-roaming)

Ty modification?Service Authentication?MIP evolution?

Ty modification?Service Authentication?MIP evolution?

IP Services

Ty

HRPD aligns to the WiMax core network.


WiMAX

BTS RNC PDSN

HRPD

BTS ASN GW

ASN

A10, A11

R6

WiMax and HRPD integrated into common IETF Core

IETF core relies on vendors to meet both WiMAX forum and 3GPP2 requirements

IMS(CSCF)

AAA

HA

PCRFPF

Common IETF Core

Ty

R3

HA support both HRPD MIPv4 (IS835) and WiMax PMIPv4 (NWGv1.0)

HA support both HRPD MIPv4 (IS835) and WiMax PMIPv4 (NWGv1.0)

The PCRF / PF supports both Ty and R3/PCC semantics and a common Rx/Tx solution.

The PCRF / PF supports both Ty and R3/PCC semantics and a common Rx/Tx solution.

AAA support different authentication schemes and EAP methods.

AAA support different authentication schemes and EAP methods.

IP services


WiMAX

AT/eAT

eAN ePDSN

AN

eHRPD

BTS ASN GW

ASN

R6

S2a PMIPv6

Legacy HRPD HA

AN AAA

PCRF

S7a

HRPD and WiMax architecture integrated under EPC (non-roaming)

IMS(CSCF)

HSS/AAA

P-GW

PCRFPF

AAA

S2a PMIPv6

PDSN

S7a

AAA

TxTy

AAA

WiMax support PCC R.7. WiMax R1.5 is considering PMIPv6.

WiMax support PCC R.7. WiMax R1.5 is considering PMIPv6.

Re-use ePDSN framework as is proposed for LTE-HRPD inter-working.

Re-use ePDSN framework as is proposed for LTE-HRPD inter-working.

IP services


WiMAX

HRPD AN SRNC aGW

HRPD AN

1xEV-DO

V-LMA

PDSN

BTS

vPCRF

ASN GW

ASN

R6

eBSUMB

Legacy 1xEV-DO

H-LMACMIP

PMIP

CMIP

H-AAA

hPCRF

V-AAA

IP servicesU19a U24a

U22a

WiMax and HRPD integrated into 3GPP2 CAN architecture


Summary – Finding a common reference architecture

• Service providers will deploy and support a mixture of legacy and emerging technologies. Sometimes more that one emerging technology.

• Inter-technology HO requirements will vary – reference architecture should accommodate both different performance requirements

• A common reference architecture must be the starting point for the discussion of all technology pairings. The reference architecture must cover:• Mobility • Authentication / Security• Policy • Charging• Fixed / Mobile convergence

• Some technology pairings have already settled on a reference architecture• HRPD-LTE (based in EPC) (agreed in 3GPP, decision in 3GPP2 pending)• HRPD-UMB (based in CAN)• WiMax-HRPD (TBD)

Nortel Confidential Information 1 Core network integration issues for inter- RAT, inter-SDO mobility...

Documents

Transcript of Nortel Confidential Information 1 Core network integration issues for inter- RAT, inter-SDO mobility...