[Freeswitch-users] Freeswitch Question regarding re-use of previously negotiated codec in response to SIP reINVITE w/o SDP

Arslan Saeed arslansaeed at gmail.com
Tue Oct 24 01:32:03 UTC 2017

Hello All,

Seeking comments/suggestions from the community on a particular Freeswitch
(FS)  behavior observed.

We see that  if there is a SIP reINVITE message (in-dialogue) from far end
switch coming to FS, it responds back with the last negotiated codec  in
the  SDP  offer as opposed to forming a brand new SDP offer with all the
supported codecs listed.

Now according to my understanding, It is recommended (not mandated) that
the SIP entity should respond to  a SIP reINVITE w/o SDP with all the
Codecs it can support and not just respoind with narrowed down list of
codecs (as negotiated in previous SDP offer/answer exchange).

This allows the far side a way to re-negotiate the codec from scratch mid
dialogue if there is a need (for example call getting transferred to new

Any configuration option that can influence this behavior?

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20171024/d381c1f9/attachment.html>

More information about the FreeSWITCH-users mailing list