Femto System Architecture for cdma2000® Systems

Number: X00-20071203-xxx

December 03, 2007Source companies grant a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. Source companies are also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of practicing an Organizational Partner’s standard which incorporates this contribution.This document has been prepared by source companies to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for discussion and is not to be construed as a binding proposal on source companies specifically reserve the right to amend or modify the material contained herein and to any intellectual property of source companies other than provided in the copyright statement above.

Source ：Rajesh Bhallarabhalla@zteusa.com

Yonggang Fangyfang@zteusa.com

Zhao Xiaowu (Frankle)zhao.xiaowu@zte.com.cn

ZTE USA Inc. 2

Takeaways from the Femto Cell Workshop• Service Requirements

– Support cdma2000 1x and HRPD in all variations

– Support all existing legacy (circuit) services

– Support all existing IP services

– E911, Regulatory, BCMCS etc ..

• Performance: comparable with macro

• Evolution: allow for phased developments– Initial support for legacy mobiles

– Future support for femto aware mobiles

– Time to market should override initial feature set creep

– Later releases can address more advanced features

• OAM&P– Configuration of radio parameters specific to Femto environment

– Operator control over service initiation / continuation

• Security– Femto authentication by core

– Core authentication by femto

– Security threats specific to femto

ZTE USA Inc. 3

Femto System Architecture Considerations• Goals

– Use standard MS devices for all cdma2000 technologies

– Support all existing services (circuit, packet, MMS, emergency, regulatory .. )

– Graceful integration with and maximize reuse of all variations of operator networks

– Minimize changes to existing network components with easy upgradability of femto and macro operator service and networks

– Scalable system – mitigating the impact on macro network as femto system grows

– Minimize complexity of system components, including the Femtocells

– Secure services, with service continuity across femto and macro networks

• Femto System Architecture Proposal– Tunneled IP-Abis approach

– Similar to the macro network architecture model – the Femtocell interfaces with the operator network via. the Abis interface

– Abis traffic encapsulated in IP-packets securely tunneled over the broadband backhaul link

– Femtocell provides BTS functions, and interfaces with existing radio and core network components

ZTE USA Inc. 4

Integration With Typical cdma2000 Networks1xRTT Circuit and 1xEV-DO Network Reference Models

1xEV-DO Network Reference Model 1xRTT Network Reference Model

• Tunneled IP-Abis approach integrates seamlessly with 1xRTT and EVDO networks– Maximizes reuse of existing operator networks

– No to minimal changes to RAN and Core network entities

– Minimizes complexity to Femtocells

ZTE USA Inc. 5

Tunneled IP-Abis ApproachFemto System Architecture Proposal

• Three femto network specific functional entities

– Femtocell

– Femto Network Gateway (FNG)

– Femto Call Manager (eBSC) – provides typical BSC+PCF functions• Split-AN functions as well

• IP-Abis to/from Femtocells securely tunneled over broadband backhaul link

• Policy based management of Abis traffic over broadband backhaul link

– (Typically) voice traffic prioritized over data traffic

• Femto Network Gateway (FNG) Functions

– IPSec termination from Femtocells for secure IP-tunnel over broadband backhaul link

– Mux/Demux/Grooming point for Abis traffic from-and-to multiple Femtocells

– Optionally – interworking function between IP-Abis and Abis traffic – depending on Call Manager (eBSC) interface requirements

– Central OAM&P Management entity for multiple Femtocells

• Abis terminates at Call Manager (BSC+PCF) which interfaces with the MSC and the PDSN for circuit and packet data services

ZTE USA Inc. 6

Tunneled IP-Abis Approach – Highlights

• Maximizes reuse of existing operator networks

– Supports all variations of 1x- & HRPD Circuit and Packet Data Services

– Uses existing interfaces and minimizes protocol enhancements

– Supports phased evolution to SIP-based and SIP/IMS-based architectures

• Superior handoff performance

• No changes to RAN elements and Core Network entities

– Changes localized to new functional entities – Femto Network Gateway and Call Manager

– Scalable architecture for supporting growing Femtocell deployments

• Minimizes complexity at Femtocells

– Femtocell provides BTS functions

– Supports legacy MS devices

ZTE USA Inc. 7

Femto Network Gateway FunctionsThe New Functional Entity

• Security Gateway

– Firewall to the macro network

– IPSec tunnel between Femtocell and FNG

– Authentication of Femtocells

– Encrypted Abis traffic over untrusted broadband link

• Abis Aggregation

– Mux/Demux point for Abis traffic from-and-to multiple Femtocells

• Abis Traffic Policy Management, Grooming & IP-Abis/Abis Interworking Function

– Policy based management of voice and data Abis traffic over the broadband backhaul link

– Grooming of Abis traffic to/from Call Manager

– Optionally – interworking function between IP-Abis and Abis traffic – depending on Call Manager (eBSC) interface requirements

• OAM&P Anchoring entity for Femtocells

IPSec SA

IP-Abis

Femtocell

Abis /IP-Abis

FNG eBSC

Policy Management, Grooming and Interworking Function (O)

FNG as OAM&P Anchor

IPSec SA

IP-Abis

Abis /IP-Abis

Femtocells

FNG eBSC

Abis Mux / Demux

IPSec SA

IP-Abis

Femtocell

Abis /IP-Abis

FNG eBSC

Security Gateway

ZTE USA Inc. 8

BSC/PCF

Femto System ArchitectureTunneled IP-Abis With Legacy Core

1x

A1/A2

Home Network

IPSec SA

PCMISUP

IP-Abis

MSC/VLRPSTNCall Manager

(eBSC)BSC+PCF

1x

A3, A7

A1/A2

FemtocellBTS

IS-41

HLR/AuC/HSS

Abis /IP-Abis

HA

MIP

t

PDSN

AAA

A10/11

Simple IP

Core IP Network

Internet

E2E DataServices

A10/11Femto Network Gateway (FNG)Security GatewayAbis Policy Management, Aggregation, GroomingAbis I/W Function (O)

ZTE USA Inc. 9

BSC/PCF A10/11

HRPD

Femto System ArchitectureTunneled IP-Abis With Legacy Core

1x

A1/A2

Home Network

IPSec SA

PCMISUP

IP-Abis

MSC/VLRPSTNCall Manager

(eBSC)BSC+PCF+split-AN

1x

A3, A7

A1/A2

FemtocellBTS+splitAN

IS-41

HLR/AuC/HSS

Abis /IP-Abis

HRPD

HA

MIP

t

PDSN

AN

AAA

AN-AAA

A10/11

A10/11

A12

A12

A13/A16

A21Femto Network Gateway (FNG)Security GatewayAbis Policy Management, Aggregation, GroomingAbis I/W Function (O)

Simple IP

Core IP Network

Internet

E2E DataServices

ZTE USA Inc. 10

Tunneled IP-Abis With Legacy CoreFunctional Capabilities

Femto Cell Capabilities 1x BTS + EVDO split-AN

Interface to Macro Network Abis over IP

• Securely tunneled over broadband backhaul link

Macro Core Network Support Legacy 1x- & HRPD Circuit and Packet Core

Where is the Call Anchored Call Manager (eBSC)

• Provides BSC+PCF + split-AN functions

• Groomed Abis /or IP-Abis interface with FNG

• Supports A1/A2, A3/A7, A10/A11, A12/A13/A16/A21 interfaces

Supplementary Services Provided by Legacy Core

Femto-Macro Handoff Inter-BSC Handoff

• eBSC – Legacy BSC/AN

Femto Gateway Functions • Security Gateway

• IP-Abis Mux/Demux over broadband link

• Policy based management of voice and data Abis traffic

• Abis Grooming /or IP-Abis over interface with Call Manager

OAM&P Support Management functions anchored at FNG

ZTE USA Inc. 11

BSC/PCF A10/11

AN

Femto System ArchitectureTunneled IP-Abis With MSCe Core

1x

A1/A2

Home Network

FemtocellBTS+splitAN

IPSec SA

PCMISUP

HRPD

HRPD

IP-Abis

AAA

AN-AAA

HA

MSC/VLR

Abis /IP-Abis

PSTNCall Manager (eBSC)BSC+PCF+split-ANA1/A2 Translation1x

A10/11

A10/11

A12

A12

A13/A16

t

PDSN

MSCe

A1p/A2p

IS-41PCMISUP

MIP

IS-41HLR/

AuC/HSS

IS-41

A3, A7

A21

Simple IP

Core IP Network

Internet

E2E DataServices

Femto Network Gateway (FNG)Security GatewayAbis Policy Management, Aggregation, GroomingAbis I/W Function (O)

ZTE USA Inc. 12

Tunneled IP-Abis With MSCe CoreFunctional Capabilities

Femto Cell Capabilities 1x BTS + EVDO split-AN

Interface to Macro Network Abis over IP

• Securely tunneled over broadband link

Macro Core Network Support MSCe (MSC emulator) for Circuit services; 1x/HRPD Packet Core

• MSCe is IP-based MSC

• Supports A1p/A2p and interfaces to PSTN, HLR, legacy MSC

Where is the Call Anchored Call Manager (eBSC)

• Provides BSC+PCF + split-AN functions

• Groomed Abis /or IP-Abis interface with FNG

• Supports A1p/A2p, A3/A7, A10/A11, A12/A13/A16/A21 interfaces

Supplementary Services Provided by MSCe

Femto-Macro Handoff Inter-BSC Handoff

• eBSC – Legacy BSC/AN

Femto Gateway Functions • Security Gateway

• IP-Abis Mux/Demux over broadband link

• Policy based management of voice and data Abis traffic

• Abis Grooming /or IP-Abis over interface with Call Manager

OAM&P Support Management functions anchored at FNG

ZTE USA Inc. 13

BSC/PCF A10/11

AN

Femto System ArchitectureTunneled IP-Abis With SIP/IMS Core

1x

A1/A2

Home Network

IPSec SA

PCMISUP

HRPD

HRPD

IP-Abis

AAA

AN-AAA

HA

MSC/VLR

Abis /IP-Abis

HLR/AuC/HSS

PSTNCall Manager (eBSC)BSC+PCF+ split-ANSIP GatewayRTP Relay

1x

A10/11

A10/11

A12

A12

A13/A16

t

PDSN

IS-41

A1/SIP

Cx

CSCF

VCCF

MGC/MGWA2/RTP

PCMISUPISC

WIN

Mg

Simple IP/Gm/SIP

Gm/SIP Mb

MIP

FemtocellBTS+splitAN

CSRV/VLR

IS-41

ISC

A3, A7

A21

Simple IP

Core IP Network

Internet

E2E DataServices

Femto Network Gateway (FNG)Security GatewayAbis Policy Management, Aggregation, GroomingAbis I/W Function (O)

ZTE USA Inc. 14

Tunneled IP-Abis With SIP/IMS CoreFunctional Capabilities

Femto Cell Capabilities 1x BTS + EVDO split-AN

Interface to Macro Network Abis over IP

• Securely tunneled over broadband link

Macro Core Network Support IMS Core

Where is the Call Anchored Call Manager (eBSC)

• Provides BSC+PCF + split-AN functions and SIP Client as well

• Groomed Abis /or IP-Abis interface with FNG

• A1/SIP signaling for 1x calls with IMS core

• A2/RTP for voice traffic transport with IMS core

• Supports A3/A7, A10/A11, A12/A13/A16/A21 interfaces, and interfaces with IMS core

Supplementary Services Provided by IMS core

Femto-Macro Handoff Inter-BSC Handoff

• eBSC – Legacy BSC/AN

Femto Gateway Functions • Security Gateway

• IP-Abis Mux/Demux over broadband link

• Policy based management of voice and data Abis traffic

• Abis Grooming /or IP-Abis over interface with Call Manager

OAM&P Support Management functions anchored at FNG

ZTE USA Inc. 15

Summary and Recommendations• Proposal is for Tunneled IP-Abis Approach for supporting Femtocells

– Femtocell provides BTS functions

– Femto Network Gateway (FNG) and Call Manager (eBSC) are other significant functional entities

• Femto Network Gateway (FNG) is the new network entity– Provides Security Gateway, Abis Aggregation and Grooming functions

– Policy based management of voice and data Abis traffic

– Optionally provides interworking function between IP-Abis and Abis traffic, depending on Call Manager (eBSC) interface requirements

– FNG is the OAM&P anchoring entity for Femtocells

• Call Manager (eBSC) provides BSC+PCF+split-AN functions

• Capabilities provided by various functional entities smoothly integrate Femtocells for with various Core network deployment scenarios:

– Tunneled IP-Abis With Legacy Core

– Tunneled IP-Abis With MSCe core

– Tunneled IP-Abis With SIP/IMS core

• Recommendations– Review and adopt