Cisco Cisco Packet Data Gateway (PDG)
HNB Gateway in Wireless Network
Features and Functionality - Base Software ▀
HNB-GW Administration Guide, StarOS Release 17 ▄
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3GPP TS 23.236 V9.0.0 (2009-12): 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Intra-domain connection of Radio Access Network (RAN) nodes to multiple Core
Network (CN) nodes (Release 9)
Network (CN) nodes (Release 9)
3GPP TS 25.468 V9.2.0 (2010-06): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; UTRAN Iuh Interface RANAP User Adaptation (RUA) signalling (Release 9)
HNB-GW supports Iu-Flex routing mechanism and other applications like many-to-many relation and load-sharing
between CN nodes with HNB-GW and CN node pooling. This mechanism provides following benefits to network
operator:
between CN nodes with HNB-GW and CN node pooling. This mechanism provides following benefits to network
operator:
Eliminates the single point of failure between an RNC/HNB-GW and a CN Node.
Ensures geographical redundancy, as a pool can be distributed across sites.
Minimizes subscriber impact during service, maintenance, or node additions or replacements.
Increases overall capacity via load sharing across the MSCs/SGSNs in a pool.
Reduces the need/frequency for inter-CN node RAUs. This substantially reduces signaling load and data transfer
delays.
Supports load redistribution with the MSC/SGSN offloading procedure.
To incorporate the concept of multiple CN nodes, Iu-Flex introduces the concept of “pool-areas” which is enabled by
the routing mechanism in HNB GW. A pool-area is served by multiple CN nodes (MSCs or SGSNs) in parallel which
share the traffic of this area between each other. Furthermore, pool-areas may overlap. From a RAN perspective a pool-
area comprises all LA(s)/RA(s) of one or more RNC/BSC or HNBGW that are served by a certain group of CN nodes in
parallel. One or more of the CN nodes in this group may in addition serve LAs/RAs outside this pool-area or may also
serve other pool-areas. This group of CN nodes is also referred to as MSC pool or SGSN pool respectively.
the routing mechanism in HNB GW. A pool-area is served by multiple CN nodes (MSCs or SGSNs) in parallel which
share the traffic of this area between each other. Furthermore, pool-areas may overlap. From a RAN perspective a pool-
area comprises all LA(s)/RA(s) of one or more RNC/BSC or HNBGW that are served by a certain group of CN nodes in
parallel. One or more of the CN nodes in this group may in addition serve LAs/RAs outside this pool-area or may also
serve other pool-areas. This group of CN nodes is also referred to as MSC pool or SGSN pool respectively.
The Iu-Flex enables a few different application scenarios with certain characteristics. The service provision by multiple
CN nodes within a pool-area enlarges the served area compared to the service area of one CN node. This results in
reduced inter CN node updates, handovers and relocations and it reduces the HLR/HSS update traffic. The configuration
of overlapping pool-areas allows to separate the overall traffic into different UE moving pattern, e.g. pool-areas where
each covers a separate residential area and all the same city centre. Other advantages of multiple CN nodes in a pool-
area are the possibility of capacity upgrades by additional CN nodes in the pool-area or the increased service availability
as other CN nodes may provide services in case one CN node in the pool-area fails.
CN nodes within a pool-area enlarges the served area compared to the service area of one CN node. This results in
reduced inter CN node updates, handovers and relocations and it reduces the HLR/HSS update traffic. The configuration
of overlapping pool-areas allows to separate the overall traffic into different UE moving pattern, e.g. pool-areas where
each covers a separate residential area and all the same city centre. Other advantages of multiple CN nodes in a pool-
area are the possibility of capacity upgrades by additional CN nodes in the pool-area or the increased service availability
as other CN nodes may provide services in case one CN node in the pool-area fails.
Iu Signalling Link Management Support
Support for Iu signal link management function for HNB-GW in accordance with the following standards:
3GPP TS 25.412 V8.0.0 (2008-12): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; UTRAN Iu interface signalling transport (Release 8)
3GPP TS 25.413 V7.9.0 (2008-06): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; UTRAN Iu interface RANAP signalling (Release 7)
3GPP TS 25.414 V9.0.0 (2009-12): 3rd Generation Partnership Project; Technical Specification Group Radio
Access Network; UTRAN Iu interface data transport and transport signalling (Release 9)
HNBGW supports RANAP protocol for management of IuPS/IuCS connections. The IU connection on the IuPS/IuCS
interface is realized using an SCCP connection towards SGSN/MSC. The SCCP could be over SIGTRAN or ATM.
interface is realized using an SCCP connection towards SGSN/MSC. The SCCP could be over SIGTRAN or ATM.