Hi, In fact they are right about that:
RFC4568 - The "crypto" attribute MUST only appear at the SDP media level RFC4568 - SRTP security descriptions MUST only be used with the SRTP transport (e.g., "RTP/SAVP" or "RTP/SAVPF"). The problem was the need to tell the remote that we optionally support RTP & SRTP. Two methods were usually used, the first one was to use a crypto attribute in a RTP/AVP media like snom does and funnily asked you to refuse, and the second was to use two media lines in the SDP one with RTP/AVP and the other with RTP/SAVP with the crypto attribute. The later one being totally legit but creating big SDP with redundant information. A third method (involving new SDP attributes called tcap/pcap) has now been recently (September 2010) officially accepted as RFC5939 and is available for reading here: http://tools.ietf.org/html/rfc5939 Regards. -------------- funny story about this one, the guys at snom filed a bug in freeswitch a while back complaining that we accepted a=crypto in an m=audio RTP/AVP section, saying we should always 488 that call as a=crypto should only be in SAVP. Turns out their default config is to send it wrong, and the only device we have issues with on this is the Snom phones. _______________________________________________ sipx-dev mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-dev/
