| == Configuring OsmoGbProxy |
| |
| OsmoGbProxy requires very little configuration, most of it being the |
| configuration of the NS links. |
| Most config options specific to OsmoGbProxy are related to SGSN pooling and |
| telling the proxy which NSE(s) it should use to talk to the SGSN(s). |
| |
| === Configure the Network Service (NS) |
| |
| A detailed description of the NS configuration can be found in <<libosmogb>>. |
| The following config snippets assume the SGSN(s) (NSEI 101 and 102) are using |
| IP-SNS and listen on 10.0.1.1:23000 and 10.0.1.2:23000 respectively. |
| |
| This would be the NS config for the SGSN(s): |
| |
| .Example: NS configuration example (SGSN) |
| ---- |
| ns |
| bind udp local |
| listen 10.0.0.1 23000 <1> |
| nse 101 <2> |
| ip-sns 10.0.1.1 23000 <3> |
| nse 102 |
| ip-sns 10.0.1.2 23000 |
| ---- |
| <1> Define the local IP/port from which to connect |
| <2> Define an NSE with NSEI |
| <3> Use IP-SNS to connect to the SGSN |
| |
| === Configure an SGSN |
| |
| Configuration of a single (non-pooling) SGSN is rather simple. |
| |
| .Example: SGSN configuration example |
| ---- |
| sgsn 101 <1> |
| name Main SGSN <2> |
| ---- |
| <1> Each SGSN is identified by its NSEI (same as in the NS configuration) |
| <2> An SGSN can optionally have a name. If none is set a default name will be used. |
| |
| === SGSN pool support |
| |
| In a SGSN pool, osmo-gbproxy is facing the problem of dividing the downlink |
| capacity of a cell towards the SGSN. The BSS advertises the per-BVC capacity |
| by means of the BSSGP FLOW-CONTROL-BVC messages, but as there are multiple |
| SGSN in a pool, they all have to share / divide that total capacity. |
| |
| By default, osmo-gbproxy advertises the full capacity to _each_ of the SGSN |
| pool members, which results in significant over-provisioning and can lead to |
| overload situations. |
| |
| The administrator can configure the _percentage_ of the overall BSS-advertised |
| capacity that shall be reported to each pool member SGSN using the |
| `pool bvc-flow-control-ratio <1-100>` configuration command. |
| |
| A setting of 100 means that each pool member is informed of 100% of the |
| BSS side capacity. |
| |
| A setting of 25 means that each pool member is informed of 25% of the |
| BSS side capacity. This would make most sense in a set-up with four |
| SGSN of equal share. |
| |
| More complex capacity division schemes are so far not supported by |
| osmo-gbproxy. |