diff options
| -rw-r--r-- | doc/manuals/aoip-mgw-options-docinfo.xml | 10 | ||||
| -rw-r--r-- | doc/manuals/aoip-mgw-options.adoc | 30 | ||||
| -rw-r--r-- | doc/manuals/mgw/osmo-bsc-new-mgw-e1.msc | 4 | ||||
| -rw-r--r-- | doc/manuals/mgw/osmo-bsc-new-mgw.msc | 4 |
4 files changed, 33 insertions, 15 deletions
diff --git a/doc/manuals/aoip-mgw-options-docinfo.xml b/doc/manuals/aoip-mgw-options-docinfo.xml index 080959443..4cec92fa7 100644 --- a/doc/manuals/aoip-mgw-options-docinfo.xml +++ b/doc/manuals/aoip-mgw-options-docinfo.xml @@ -7,6 +7,14 @@ Initial version of the proposal for internal discussion. </revremark> </revision> + <revision> + <revnumber>1.0</revnumber> + <date>November 2020</date> + <authorinitials>Harald Welte</authorinitials> + <revremark> + Update with changes on what was actually implemented in recent years; change from future to past tense. + </revremark> + </revision> </revhistory> <authorgroup> @@ -24,7 +32,7 @@ </authorgroup> <copyright> - <year>2017</year> + <year>2017-2020</year> <holder>sysmocom - s.f.m.c. GmbH</holder> </copyright> diff --git a/doc/manuals/aoip-mgw-options.adoc b/doc/manuals/aoip-mgw-options.adoc index 124c03fda..62163ccc4 100644 --- a/doc/manuals/aoip-mgw-options.adoc +++ b/doc/manuals/aoip-mgw-options.adoc @@ -5,8 +5,8 @@ This document serves as a paper to illustrate the different configurations of OsmoBSC in terms of integration with BTSs and MSCs. -The document should accompany us in the 2017 development cycle which -includes the _death of the NITB_, i.e. the move away from OsmoNITB to +The document was created ahead of the 2017 development cycle which +included the _death of the NITB_, i.e. the move away from OsmoNITB to having OsmoBSC in all configurations, whether with a proprietary/external MSC or with OsmoMSC. @@ -24,8 +24,13 @@ such as === Classic GSM RAN with E1 based Abis and E1 A -This configuration was actually never supported by OpenBSC, as E1 BTS -support was so far for NITB only, but not for OsmoBSC. +This is how GSM was originally specified when it was introduced: E1/T1 +circuits on all interfaces, no IP anywhere. + +This configuration was actually never supported by OpenBSC, as E1 +support was always only on the Abis side (OpenBSC, OsmoNITB and today OsmoBSC). + +We never supported A interface over E1. It could be done if there was a need. [mscgen] ---- @@ -53,11 +58,11 @@ Release 7 of 3GPP included an official specification on how an interoperable A-over-IP (AoIP) interface shall look like. As more modern MSCs at operators tend to favor implementing 3GPP AoIP -rather than the proprietary SCCPlite based A interface, it becomes +rather than the proprietary SCCPlite based A interface, it became necessary for OsmoBSC to support this. At the same time, for compatibility reasons, the classic SCCPlite -support shall be kept, if possible with reasonable effort. +support is kept in OsmoBSC as a configuration option. [mscgen] ---- @@ -65,11 +70,16 @@ include::{srcdir}/mgw/osmo-bsc-new-mgw.msc[] ---- -=== OsmoBSC 2017+: 3GPP AoIP + Abis/E1 +=== OsmoBSC 2020+: 3GPP AoIP + Abis/E1 + +Since OsmoNITB was deprecated in 2017, and OsmoBSC only supported Abis/IP, +we temporarily lost the ability to use classic E1 based BTSs. In 2020, +we re-introduced and re-tested the support of Abis/E1. -Since OsmoNITB will soon be deprecated, we will use OsmoBSC in all -Osmocom GSM ntework setups, requiring the support for classic E1/T1 -based BTSs from OsmoBSC. +Fro the control plane of Abis (RSL, OML) the E1 support via libosmo-abis +never really ceased to exist. But for the user plane, E1 support had to be +introduced to osmo-mgw, and osmo-bsc needed to be taught how to configure +E1 endpoints at the MGW. The related call flow for such setups looks like this: [mscgen] ---- diff --git a/doc/manuals/mgw/osmo-bsc-new-mgw-e1.msc b/doc/manuals/mgw/osmo-bsc-new-mgw-e1.msc index 04b114fff..676948cdd 100644 --- a/doc/manuals/mgw/osmo-bsc-new-mgw-e1.msc +++ b/doc/manuals/mgw/osmo-bsc-new-mgw-e1.msc @@ -1,8 +1,8 @@ # MO-Call with E1 BTS + OsmoBSC with true 3GPP AoIP (planned -# osmo-bsc_mgcp has to be extended to true MGW functionality! +# osmo-mgw has to be extended to true MGW functionality! msc { hscale=2; - ms [label="MS"], bts [label="E1 BTS"], bsc[label="OsmoBSC"], mgcp[label="osmo-bsc_mgcp"], m_sc[label="MSC"]; + ms [label="MS"], bts [label="E1 BTS"], bsc[label="OsmoBSC"], mgcp[label="osmo-mgw"], m_sc[label="MSC"]; ms box m_sc [label="We assume a SDCCH is already established"]; ...; diff --git a/doc/manuals/mgw/osmo-bsc-new-mgw.msc b/doc/manuals/mgw/osmo-bsc-new-mgw.msc index e618bb721..d6450bd22 100644 --- a/doc/manuals/mgw/osmo-bsc-new-mgw.msc +++ b/doc/manuals/mgw/osmo-bsc-new-mgw.msc @@ -1,7 +1,7 @@ -# MO-Call with OsmoBTS + OsmoBSC with true 3GPP AoIP (planned) +# MO-Call with OsmoBTS + OsmoBSC with true 3GPP AoIP msc { hscale=2; - ms [label="MS"], bts [label="OsmoBTS"], bsc[label="OsmoBSC"], mgcp[label="osmo-bsc_mgcp"], m_sc[label="MSC"]; + ms [label="MS"], bts [label="OsmoBTS"], bsc[label="OsmoBSC"], mgcp[label="OsmoMGW"], m_sc[label="MSC"]; ms box m_sc [label="We assume a SDCCH is already established"]; ...; |