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New Member

E&M Signaling


I have implemented CAS with a E&M Wink-Start signaling on my 3640 router to a PBX that I have. After implementation, it works half the time. When the call fails, what I see is that same call uses different channel for send and receive when I use show voice port command. For example, it uses channel 9 for send and channel 10 for receive. Has any body seen this probelm?

Any kind of help can be appreciated. Also, can 3640 suppport CCS with wink-start? One more thing, is there a way to change the unknown caller id to something different that can be displayed on th IP Phone?

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Cisco Employee

Re: E&M Signaling

Not sure why you would be using 2 channels for one call, but for the unknown calledid. There is a service parameter called "UnknownCallerID". You can set this to be the callerid when none is provided.

Thank you,


New Member

Re: E&M Signaling

Hello Hachul,

You said the call works half of the time. Does the call work all of the time in one direction and not work all of the time in the other direction? I was routing a call to a PBX from a router and, for some unknown reason, the PBX did not recognize that the call setup was initiated by the calling party and attempted to setup a second call (as in a brand new call) back to the router (on a different channel). The PBX guru’s did some configuration magic (after a little prodding) that fixed the problem. I never did get a satisfactory explanation of what was wrong. It appeared to be a PBX problem.