1. Femto System Architecture for cdma2000® Systems Number: X00-20071203-xxx
Source：
Rajesh Bhalla
Yonggang Fang
Zhao Xiaowu (Frankle)
December 03, 2007
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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
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources

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

4. Integration With Typical cdma2000 Networks 1xRTT Circuit and 1xEV-DO Network Reference Models
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
1xRTT Network Reference Model
1xEV-DO Network Reference Model

5. Tunneled IP-Abis Approach Femto 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
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources

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
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources

7. Femto Network Gateway Functions The 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
Security Gateway
IPSec SA
IP-Abis
Abis / IP-Abis
Femtocells
FNG
eBSC
Abis Mux / Demux
IPSec SA
IP-Abis
Femtocell
Abis / IP-Abis
FNG
eBSC
Policy Management, Grooming and Interworking Function (O)
FNG as OAM&P Anchor

8. Femto System Architecture Tunneled IP-Abis With Legacy Core
BSC/PCF
MSC/VLR
PCM ISUP
A1/A2
A10/11
PSTN 1x
IS-41
Femto Network Gateway (FNG) Security Gateway Abis Policy Management, Aggregation, Grooming Abis I/W Function (O)
HLR/AuC/HSS
Call Manager (eBSC) BSC+PCF
A3, A7
Home Network 1x
A1/A2
IPSec SA
Abis / IP-Abis
Femtocell BTS
IP-Abis
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources
A10/11
Simple IP
Core IP Network
Internet
E2E Data
Services t
PDSN
AAA
MIP HA

9. Femto System Architecture Tunneled IP-Abis With Legacy Core
BSC/PCF
MSC/VLR
PCM ISUP
A1/A2
A10/11
PSTN 1x
A21
IS-41
Femto Network Gateway (FNG) Security Gateway Abis Policy Management, Aggregation, Grooming Abis I/W Function (O)
HLR/AuC/HSS
Call Manager (eBSC) BSC+PCF +split-AN
A3, A7
Home Network 1x
A1/A2
IPSec SA
Abis / IP-Abis
IP-Abis
HRPD
Femtocell BTS+splitAN
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources
A12
A10/11
Simple IP
Core IP Network
Internet
E2E Data
Services t
PDSN
AN-AAA
A13/A16
A10/11
AAA
MIP
A12
HRPD AN HA

10. Tunneled IP-Abis With Legacy Core Functional 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

11. Femto System Architecture Tunneled IP-Abis With MSCe Core
BSC/PCF
MSC/VLR
PCM ISUP
A1/A2
A10/11
PSTN 1x
A21
IS-41
Femto Network Gateway (FNG) Security Gateway Abis Policy Management, Aggregation, Grooming Abis I/W Function (O)
HLR/AuC/HSS
Call Manager (eBSC) BSC+PCF +split-AN A1/A2 Translation
A3, A7
IS-41
Home Network
PCM ISUP
IS-41 1x
MSCe
IPSec SA
Abis / IP-Abis
A1p/A2p
IP-Abis
HRPD
Femtocell BTS+splitAN
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources
A12
A10/11
Core IP Network
Internet
E2E Data
Services t
PDSN
AN-AAA
Simple IP
A13/A16
A10/11
AAA
MIP
A12 AN HA
HRPD

12. Tunneled IP-Abis With MSCe Core Functional 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

13. Femto System Architecture Tunneled IP-Abis With SIP/IMS Core
BSC/PCF
MSC/VLR
PCM ISUP
A1/A2
A10/11
PSTN 1x
A21
IS-41
Femto Network Gateway (FNG) Security Gateway Abis Policy Management, Aggregation, Grooming Abis I/W Function (O)
IS-41
HLR/AuC/HSS
Call Manager (eBSC) BSC+PCF + split-AN SIP Gateway RTP Relay
A3, A7
CSRV/VLR
WIN
Home Network Cx
VCCF
PCM ISUP
ISC 1x
CSCF
ISC
IPSec SA
Abis / IP-Abis
A1/SIP Mg
MGC/MGW
IP-Abis
A2/RTP
HRPD
Simple IP/ Gm/SIP
Femtocell BTS+splitAN
OAM&P
Configuration of radio parameters such specific to Femto environment
Such as neighbor lists, pilot PN offset, power level, other radio resources
A12
A10/11
Simple IP
Core IP Network
Internet
E2E Data
Services
Gm/SIP Mb t
PDSN
AN-AAA
A13/A16
A10/11
AAA
MIP
A12 AN HA
HRPD

14. Tunneled IP-Abis With SIP/IMS Core Functional 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

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