Feature #3798

Implement bandwidth-efficient AMR payload as per RFC 4867 Section 4.3

Added by laforge almost 2 years ago. Updated over 1 year ago.

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Unfortunately the 3GPP has missed to specify which of the two variants are to be used on the AoIP interface. While 3GPP TS 48.103 specifies almost every other detail, it doesn't contain any statement on which of those variants shall be supported by either BSC nor MSC/MGW on AoIP.

The osmocom stack so far implements exclusively octet-aligned mode. However, some MSC/MGW seem to be implementing [only?] bandwidth-efficient mode.

It would be possible to add OsmoMGW support for bandwidth-efficient mode and then have it convert between the two modes such as octet-aligned on Abis and bandwidth-efficient on A. Identification should happen via the MIME type within the SDP (within MGCP).

OsmoBSC could then have a setting which determines the MIME type to be specified for the A-side RTP connections.

Related issues

Related to Cellular Network Infrastructure - Bug #2728: Align better with 48.103 for AoIP user plane (AMR marker bit for frame following ONSET)Stalled12/09/2017


#1 Updated by laforge almost 2 years ago

  • Related to Bug #2728: Align better with 48.103 for AoIP user plane (AMR marker bit for frame following ONSET) added

#2 Updated by laforge over 1 year ago

  • Status changed from New to Resolved
  • Assignee set to dexter
  • % Done changed from 0 to 100

this ticket has been forgotten. Has been implemented in

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