> Comments are more than welcome. Hi. This draft appears to describe how SBCs can assist IPv4-/IPv6-only nodes in communicating with each other by modifying SDP offers and SDP answers. I presume this is done to avoid doing ICE on the endpoints, even though draft-ietf-sipping-v6-transition says IPv6 endpoints SHOULD implement ICE to assist with the IPv6 transition -- but I'm not sure; the document doesn't discuss why the atypes is superior to ICE. I think I understand why the sip.atypes media feature tag is useful (because the SBC can only really know about the endpoint's ability to handle signaling, not media). But is there harm in the SBC assuming the obvious -- namely, that an incoming IPv4 SIP signaling connection from an endpoint means the endpoint supports IPv4 media, and that an incoming IPv6 signaling connection from an endpoint means the the endpoint supports IPv6 media? draft-boucadair-sipping-ipv6-atypes also uses ANAT (RFC4091/RFC4092) which has two deficiencies: (a) an ANAT offer is confusing to SDP receivers that are ANAT-unaware (because of the multiple m= lines some SIP endpoints supposedly reject the invitation) and (b) ANAT will be deprecated when ICE is published. -d _______________________________________________ Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping This list is for NEW development of the application of SIP Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use sip@xxxxxxxx for new developments of core SIP
