some info on this: http://tools.ietf.org/html/draft-muthu-payload-offer-answer-g723-g729-00

On May 17, 2015, at 4:17 AM, Dmitry Saratsky <simpot@gmail.com> wrote:

Hi all,

Can you please show me CORRECT SDP media examples for all possible G.729  annexes (need only G.729, G.729A, G.729B and G.729AB).

How should correct SDP look like for each case of the above including fmtp parameters and maybe other parameters?