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New Member

One way voice call


I have a Hub and Spoke VoIP over Frame-Relay network working fine.

The central point contains a 3660 (c3660-is-mz.121-3a.t1.bin) and an AS5300 (c5300-is-mz.120-7.T). In the branch offices I have 2600 (c2600-is-mz.120-7.T.bin), and 1750 (c1700-sv3y-mz.121-2.T). Now I am doing an expansion with 1751 (c1700-sv3y-mz.122-2.XQ1.bin) with Voice NT / TE BRI interfaces.

From this particular equipment (1751) I have one-way voice for every remote node including central AS5300.

I already test two of this 1751 locally with fxs interfaces and it works fine.

Any idea to resolve this problem ?

Thanks in Advance,

NOTE: I have not routing problems between 1751 and remote nodes.


Re: One way voice call

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New Member

Re: One way voice call

Sounds like you have only one side of the call leg built.

Check your dial-peers on both sides to verify that they are set up properly.



New Member

Re: One way voice call

If you have 1-way voice, you've got a full path for call setup. Debug ip udp on both end routers:

Do you see udp packets going both directions on both routers? If not, make sure your IP routing is OK.

Are the packets more or less the same size? They should be, if not, one of your ciscos has a problem, probably with the DSP software.

If you see UDP going both directions, on both end routers, with a decent packet size, then you may have a DSP problem or a problem with the signaling to the PBX/telco switch. Hope this narrows it down a bit.

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