MBSF: SDP parts for User Service Announcement

[davidjwbbc]

References

TS 26.517 V18 Clause 6.2.2 - MBS profile for Session Description.
TS 26.346 V18 Clause 7.3.2 - MBMS Download delivery method.

Introduction

The User Service Descriptions Bundle is a multipart/related MIME bundle which contains as the root file a User Service Descriptions document followed by several parts with the referenced files. There will be an SDP object referenced by each Distribution Session described in each User Service Description that forms part of the root document. This SDP object is required to be included as an extra multipart part of the bundle.

Service Description

Each SDP contains a description of the transmission parameters for a Distribution Session.

Field	Part	Cardinality	Source	Format	Example
a=source-filter:	session	1	MBSDistributionSessionInfo.mbsSessionId.ssm.sourceIpAddr	incl IN {IP4|IP6} {*|<multicast-destination>} <source-addr>	a=source-filter:incl IN IP4 * 192.168.0.1
a=flute-tsi:	session	1	TSI as assigned to the MBSTF	<tsi>	a=flute-tsi:1
t=	session	1..*	activePeriod[].startTime and activePeriod[].endTime or start and end of current or next active period from an activePeriodRepRule	{0|<start-time-seconds-since-epoch>} {0|<end-time-seconds-since-epoch>}	t=3981715800 3981716400 (use 0 to remove start and/or end bounds)
c=	media	1	MBSDistributionSessionInfo.mbsSessionId.ssm.destIpAddr	IN {IP4|IP6} <multicast-destination>	c=IN IP4 232.0.0.1
m=	media	1	port number as sent to MBSTF	application <port> FLUTE/UDP 0	m=application 12345 FLUTE/UDP 0

[davidjwbbc]

Having reviewed several libraries, other binary sources and RFC 8866 (SDP) it will be more efficient to write our own SDP formatter library. This can live in rt-common-shared for reuse.