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New Member

IP Phone register but no dial tone

I have a remote site connecting to the central site via microwave. When I put an IP phone at the remote site the phone register but if I pick up the handset there is no dial tone and I can't make any calls. I have tried using other handsets but the same problem occur. Does anybody know where I can get the whitepaper to understand how IP phone signalling work or know how I can troubleshoot this problem.

New Member

Re: IP Phone register but no dial tone

Best palce to start is the CCM trace's.

Let the ip phone register with a CCM node. Once it has registered open the ccm trace, (ensure you have set the trace level to arbitarty, via servicability)

Then search for the MAC addr of the phone in the trace file. YOu should find a message device registration request.

This will have a TCP handle assigned to it for the length of the regsitartion period.

I would suggest that you then search for the enxt messagaes using the TCP handle.

Then try using the ip phone,m you should expect to see a station off-hook message followed by some return messages in the trace file.

If these are being sent out then you need to check that they arrive at the destination phone.

A sniffer trace using etherreal should do the trick.

This will let you see if you recieve the packets.

You can also sniff at the call manager side if you find the trace too much to read, just set some filters on the sniffer.


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