CUCM SCCP to SIP RTP session not establishing

Unanswered Question
Sep 27th, 2010
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I have a (7.1)clster with where i have registerd SCCP and SIP Phone with same region same device pool and G711 codec.

Now the issue is while calling from SCCP phone to SIP or from SIP to SCCP , The phone ring but when the phone call off-hook the call gets dropped.


I think it is not able to establlish the RTP session, both the phone are in same premises so there is no option for the firewallblocking the RTp.

What can be the issue ib this case.


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gogasca Thu, 09/30/2010 - 15:26
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which model of IP Phone youy are using?

SW and version?

Same subnet?

for SCCP side check OLC, OLC ack and StartMediaTransmission in CUCM traces/Sniffer capture

for SIP side INVITE and 200 OK, ACK SDP information

You can setup an sniffer capture and
verify where RTP packets are being sent...


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