A.12 Transport

29.3323GPPMedia Gateway Control Function (MGCF) - IM Media GatewayMn interfaceRelease 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

Table A.12/1: Transport

Supported Transports:

SCTP(recommended) (NOTE1).

SCTP/M3UA(optional) optional – as defined in IETF RFC 3332 [24] with options detailed in 3GPP TS 29.202 [25] (NOTE2).

UDP(optional).

NOTE: If using SCTP as defined in IETF RFC 2960 [15] the MGW shall always be the node to perform the "Initiation".

NOTE1 H.248 is "SCTP user" in this case of H.248/SCTP/IP based transport according ITU-T Rec. H.248.4 [38]. The number of used SCTP Streams for traffic of the H.248 Control Association must be defined, see § 8/H.248.4 [38]. A single SCTP Stream is the default assumption ("Single-Stream Mode") in this Profile.

NOTE2 This is slightly different with regards to SCTP encapsulation. H.248 is "M3UA user" in this case of H.248/M3UA/SCTP/IP based transport. H.248 Messages are corresponding to M3UA user protocol data units. "SCTP multistreaming" may be also applied (see § 1.4.7/RFC 3332). If not then the complete M3UA traffic is mapped on a single SCTP Stream, i.e., the Single-Stream Mode.

NOTE3 Checksum calculation for SCTP shall be supported as specified in RFC 3309 [43] instead of the method specified in RFC 2960 [15].

Table A.12/2: Segmentation

Segmentation Supported:	No
NOTE: This field requires at least version 3 of the H.248.1 protocol.

Table A.12/3: Support of Control Association Monitoring

Control Association Monitoring Supported:

Monitoring mechanism is dependent on used H.248 transport (see Table A.12/1):

SCTP: inherent capability of SCTP (NOTE 1)

SCTP/M3UA: inherent capability of SCTP

UDP:

1. H.248.14 (MGW-driven monitoring)

2. Empty AuditValue on ROOT (MGC-driven monitoring)

NOTE 1: Use of H.248.14 [29] for this is FFS