| [[overview]] |
| == Overview |
| |
| |
| [[intro_overview]] |
| === About OsmoHNBGW |
| |
| OsmoHNBGW implements the Home NodeB Gateway function in the 3G network architecture. It serves |
| as a gateway between the classic 3G core network (CN) domain with its IuCS and IuPS interface |
| and the femtocell based RAN. |
| |
| A typical 3G network consisting of Osmocom components will look as illustrated in the following |
| diagram: |
| |
| [[fig-3g]] |
| .Typical 3G network architecture used with OsmoHNBGW |
| ---- |
| +------------+ +--------+ +----------+ +---------+ |
| UE <-->| hNodeB |<--Iuh---->| HNB-GW |<--IuCS-->| OsmoMSC |<--GSUP-->| OsmoHLR | |
| UE <-->| femto cell | ...-->| | ...-->| | | | |
| | | | | +----------+ +---------| |
| +------------+<--GTP-U | | |
| \ | | +------+ +------+ |
| | | |<--IuPS-->| SGSN |<--GTP-C-->| GGSN | |
| | +--------+ ...-->| | GTP-U-->| | |
| | +------+ / +------+ |
| \_______________________________/ |
| ---- |
| |
| The HNB-GW performs a translation interface between the IuCS/IuPS interfaces on the one hand |
| side, and the Iuh interface on the or ther hand: |
| |
| ---- |
| Iuh IuCS/IuPS |
| |
| NAS +----+----+ +----+----+ |
| Non-Access Stratum | CC | MM | | CC | MM | |
| - - - - - - - - - - - +----+----+-------+ +----+----+ |
| | RANAP | | H | RANAP | |
| Access Stratum +---------+ HNBAP | N +---------+ - - SCCP USER SAP |
| | RUA | | B | SUA | \ |
| +---------+-------+ - +---------+ | |
| | SCTP | G | SCTP | } SIGTRAN |
| +-----------------+ W +---------+ | |
| | IP | | IP | / |
| +-----------------+ +---------+ |
| ---- |
| |
| On the femtocell (Home NodeB) side, OsmoHNBGW implements the Iuh interface as specified by 3GPP. |
| |
| === The Iuh interface |
| |
| Iuh consists of the following sub-layers: |
| |
| - HNBAP (Home NodeB Application Part) |
| - RUA (RANAP User Adaptation, between RANAP and SCTP |