> > > If UDP is used for transport, empty UDP packets can be sent to keep the >> NAT-binding alive. >> > > Sending empty UDP is not standard complaint. Sending a STUN binding > request, as described in https://tools.ietf.org/html/rfc5626#section-3.5.2 > is safer. >
This is not an option, if you are not using STUN. There are lot of good reasons not to use STUN, e.g. because your IMS provides sophisticated NAT traversal functionalities or your NAT type is not compatible with STUN. But yes, UDP keep alive packages are not standardized in RFC5626, but many well known vendors like Polycom or Yealink implemented such keep alives. Best Regards Philipp > _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
