| Harald Welte | a5ad7a4 | 2019-03-21 22:52:44 +0100 | [diff] [blame] | 1 | == Configuring OsmoGbPROXY |
| 2 | |
| 3 | TBD. Unfortunately this chapter of the manual still needs to be written. |
| 4 | Osmocom has very limited funding and support resources; Feel free to help |
| 5 | us completing this documentation by contributing with code, documentation |
| 6 | or by supporting the developers financially. |
| Harald Welte | 209dc9f | 2020-12-12 19:02:16 +0100 | [diff] [blame^] | 7 | |
| 8 | |
| 9 | === SGSN pool support |
| 10 | |
| 11 | In a SGSN pool, osmo-gbproxy is facing the problem of dividing the downlink |
| 12 | capacity of a cell towards the SGSN. The BSS advertises the per-BVC capacity |
| 13 | by means of the BSSGP FLOW-CONTROL-BVC messages, but as there are multiple |
| 14 | SGSN in a pool, they all have to share / divide that total capacity. |
| 15 | |
| 16 | By default, osmo-gbproxy advertises the full capacity to _each_ of the SGSN |
| 17 | pool members, which results in significant over-provisioning and can lead to |
| 18 | overload situations. |
| 19 | |
| 20 | The administrator can configure the _percentage_ of the overall BSS-advertised |
| 21 | capacity that shall be reported to each pool member SGSN using the |
| 22 | `pool bvc-flow-control-ratio <1-100>` configuration command. |
| 23 | |
| 24 | A setting of 100 means that each pool member is informed of 100% of the |
| 25 | BSS side capacity. |
| 26 | |
| 27 | A setting of 25 means that each pool member is informed of 25% of the |
| 28 | BSS side capacity. This would make most sense in a set-up with four |
| 29 | SGSN of equal share. |
| 30 | |
| 31 | More complex capacity division schemes are so far not supported by |
| 32 | osmo-gbproxy. |