Protocols Around the Home Node B Gateway
========================================

                                 +--------+
                             ,-->| Osmo   |
                            /    | MGCPGW |
                            |    |        |<--MGCP
                            |    +--------+       \
                            /                     |
        +------------+<--RTP     +--------+       `->+----------+
 UE <-->| hNodeB     |           | Osmo   |          | OsmoMSC  |        +------+
 UE <-->| femto cell |<--Iuh---->| HNB-GW |<--IuCS-->|          |        | Osmo |
        |            |           |        |          |     (VLR)|<-GSUP->| HLR  |
        |            |           |        |          +----------+  GSUP->+------+
        +------------+<--GTP-U   |        |                       /
                              \  |        |          +------+<---'       +------+
                              |  |        |<--IuPS-->| Osmo |<--GTP-C--->| Open |
                              |  +--------+          | SGSN |   GTP-U--->| GGSN |
                              |                      +------+  /         +------+
                              \_______________________________/


                      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      |  /
                      +-----------------+         +---------+


Various SIGTRAN implementations:

                IuCS/IuPS
                  usual
                   |     simplest
                   |       |
                   v       v
  +------+------+------+-----+
  | SCCP | SCCP |      |     |
  +------+------+ SCCP |     |
  | MTP3 | MTP3 |      |     |
  +------+------+------+ SUA |
  | MTP2 |      |      |     |
  +------+ M2UA | M3UA |     |
  | M2PA |      |      |     |
  +------+------+------+-----+
  |           SCTP           |
  +--------------------------+
  |            IP            |
  +--------------------------+

UE (User Endpoint) == MS (Mobile Subscriber) == mobile device