Feature #4852
Updated by laforge about 3 years ago
In order to support GSM-R ASCI, we'd need VGCS/VBS support.
In the BSC, this mostly means the following:
* definition of VBS/VGCS areas e.g. via VTY (or simply assume all areas are global in initial implementation)
* Abis: generation of RSL NOTIFICATION messages
* A interface / BSSMAP
** VGCS/VBS SETUP + VGCS/VBS SETUP ACK + VGCS/VBS SETUP REFUSE messages
** VGCS/VBS ASSIGNMENT REQ
** UPLINK REQUEST, UPLINK RELEASE NOTIFICATION, UPLINK SEIZED COMMAND, UPLINK REQUEST ACK, UPLINK REJECT
** VGCS ADDITIONAL INFORMATION
There's quite a bit of state machines and logic required.
* VGCS/VBS setup procedure
* VCGS/VBBS assignment proceure
** procedures according to TS 48.008 section 3.1.21, 3.1.22
* handling of uplink related allocation and release procedures (VGCS)
* periodic NCH transmissions
* SACCH indications of NCH changes
* managing the bsc-colocated osmo-mgw
** allocate a 'broadcast' endpoint with one sender and many recipients
** RTP connections for each BTS
** RTP connection to the MSC
** modifying rcvonly/sendonly/sendrecv according to current talker setate (VGCS)
