Document user plane handling with BSC+MSC co-located OsmoMGW, Osmux, and outlook
I erased previous task #2909 by error. Recreating.
We need some kind of documentation on how the new, OsmoMGW-enabled user plane domain looks like. This includes the BSC-colocated OsmoMGW as well as the MSC-colocated OsmoMGW, as well as details on the use of MGCP between the respective call agents and MGW instances. Non-exhaustive list of topics to include: * message sequence charts * diagrams showing netwokr elemetns and control + user plane relationships * dynamic endpoint allocation * outlook on re-integrated support for E1 BTS * name MGCP/MGW related config parameters in BSC and MSC config * outlook on Osmux re-integration * interaction between MNCC signaling and user plane at MSC * outlook on IuUP This is not really a user manual of a given single network element, but a document that describes the relation between the respective elements. Individual sections/chapters could possibly be reused/included into the BSC/MGW/MSC user manuals, but let's have a look at this after having a draft of that document. Let's also make sure we use any existing bits and pieces from the osmo-mgw manuals (and the ladder diagrams I created there), as well as the wiki and possibly any not-yet-public ladder diagrams dexter might have created in recent months.
Documented the MGCP/OsmoMGW specific part in here:
- Add some shared section in OsmoBSC, OsmoMSC manuals (and maybe osmux reference manual too) to show with flow diagrams how calls work, with AoIP and with SCCPlite. Can use  as a source for the diagrams.
- Add BSC specific section explaining how to configure it with VTY and adding BSC related considerations
- Add MSC specific section explaining how to configure it with VTY and adding MSC related considerations
- % Done changed from 0 to 10
I started the Osmux "network-wide" documentation in here:
- % Done changed from 10 to 80
I finally moved much of the documentation to a common place, where will then be included by User Manuals of OsmoMGW, OsmoMSC, OsmoBSC and OsmoBSCNAT:
I also required this commit to be able to include the files from osmo-gsm-manuals in osmo-*.git/doc/manuals/chapters/*.adoc:
Then, each osmo-* repo includes the bits from osmo-gsm-manuals + some specific documentation from their own repos:
MGW: https://gerrit.osmocom.org/c/osmo-mgw/+/14681 doc: Add Osmux documentation to OsmoMGW User Manual
BSC: https://gerrit.osmocom.org/c/osmo-bsc/+/14840 doc: Add Osmux documentation to User Manual
MSC: https://gerrit.osmocom.org/c/osmo-msc/+/14841 doc: Add Osmux documentation to User Manual
TODO: BSC-NAT user manual related work.