FXS under SCCP controll one-way audion

Unanswered Question
Jun 17th, 2008
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Hi, I have got a scenario like this..

gateway 1 (with 4 fxs ports connected to analogue phones using SCCP)

gateway 2 (with 4 fxs ports connected to analogue phones using SCCP).

The DDI for the analogue phones(polycoms) matches the DDI range for the 1st gateway...Hence an Incoming call to the Polycom phones..goes like this

1. A call comes in on the 1st gateway trunk for the polycoms since thier extension is in its DDI range...(matches the DDI on the 1st gateway)

2. It then goes to callmanager

3. Callmanager then sends it to the 2nd gateway

4. callmanager then connects the 2nd gateway to the 1st gateway to stream the RTP traffic....(since the phone is connected to the 2nd gateway)


The problem is that its only one way audion that we get when an external call is made and received in this scenario.

Attached is the config for both gateways..

Is ther anything I can do to resolve this

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Overall Rating: 1 (1 ratings)
ivillegas Mon, 06/23/2008 - 13:00
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An improperly configured Cisco IOS Gateway, a firewall, or a routing or default gateway problem, among other things can cause this problem. Some Cisco IOS gateways, such as the VG200, have IP routing disabled by default. This will lead to one-way voice problems.




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