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New Member

PSTN Call Seen as Internal Extension

We have users at a remote site that, when they receive a call from the PSTN where the last 4 digits of the calling party number matches an existing extension defined in CallManager, it appears on the phone as an internal call.

For example:

Existing CCM extension: 1927 (Display name - Mary)

PSTN - Calling party number: 4105551927

The internal user will see a call from 4105551927 as "call from Mary" and think it is a coworker. Also, if the internal user does not pickup and it forwards to voicemail it will say "message from Mary".

I ran a debug and I see the call come into the MGCP gateway with the full 10 digits. There are no applicable translation patterns that match that would shorten the calling party number to 4 digits.

Has anyone seen this before?


Re: PSTN Call Seen as Internal Extension

Could you please upload the debug and also a CCM detailed trace with the digit analysis set to complex?


New Member

Re: PSTN Call Seen as Internal Extension

The debug is attached but I don't have full access to the Callmanager to collect traces for this particular customer. I connect remotely and I'm not permitted to install anything on the PC that I use to bring up the CCM web interface.

The incoming call looks correct, the gateway config on the callmanager specifies the significant digits as "4" so it shortens the called party number but as far as I can tell that shouldn't affect the calling party number correct?

The CCM version is 6.1.2.

Re: PSTN Call Seen as Internal Extension

correct, besides CCM routes the call based on Called party number, not calling party. That is why we should take a look to the trace to see what is going on internally.

Cisco Employee

Re: PSTN Call Seen as Internal Extension

is this a direct call or is there anything in between???



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