Need your assistance to identify the root cause of one issue which I am facing. I have noted that whenever we make an OB call , a Re-Invites happen even though there is no codec mismatch / hold or transfer. Call flow is as given below
IP phone -Leaf cluster -SME-CUSP-CUBE-SIP trunk to Service provider
Service provider responds with 183 session progress with SDP for initial INVITE , CUBE send PRACK response with SDP to Service provider and forward the 183 session progress to SME via CUSP. SME responds to PRACK with SDP but it uses SME IP address in the SDP [C=IN IP4 xx.xxx.xx.xx(SME IP)] instead of the Originating Cisco IP phone IP address . Service provider sends 180 ringing and then 200OK response. When SME receives 200 OK it sends ACK with out SDP and then send a Re-Invite.
There are no MTPs/ Transcoders configured in SME so I would like to know why is it using its IP address in the SDP instead of phone IP. It also include the below attribute in SDP
Solved! Go to Solution.
Thank you for your response, enabling Early offer best effort on CUCM leaf or SME would need a MTP resource right ?
ı have a smilar case with our provider we need to send multiple codec with re-invite that mean cube is sending only g711alaw but we want to send two codec with sdp (g711alaw and ulaw) How can we do that ?
Is it possible to send two codec with re-invite
By the way I have configured
midcall-signaling passthru media-change