K.2 Recommend T.38 configuration

29.1633GPPInterworking between the IP Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS) networksTS

UDPTL is recommended as T.38 transport.

NOTE: MTSI client use UDPTL as transport (see 3GPP TS 24.173 [88]).

Table X.2.1 lists values for the T.38 SDP attributers that are recommended to be supported.

Table K.2.1: Recommended configuration for T.38 SDP attribute values

T38FaxVersion	Version 2 or higher. (NOTE 1)
T38MaxBitRate	14 400
T38FaxFillBitRemoval	FALSE
T38FaxTranscodingMMR	FALSE
T38FaxTranscodingJBIG	FALSE
T38FaxRateManagement	‘transferredTCF’
T38FaxMaxBuffer	1800
T38FaxMaxDatagram	At least 150
T38FaxMaxIFP	40 (NOTE 2)
T38FaxUdpEC	‘t38UDPRedundancy’
T38FaxUdpECDepth	Minred: 1; Maxred: 2 (NOTE 2)
T38FaxUdpFECMaxSpan	3 (NOTE 2)
T38ModemType	‘t38G3FaxOnly’ (NOTE 2)
NOTE 1: Version 0 is the default value that applies if the T38FaxVersion SDP attribute is not signalled. No SDP attributes are defined in this T.38 version 0. With version 4, default values for the SDP attributes apply if the attributes are omitted. NOTE 2: Only applicable for T.38 version 4.