Forcing G711u/aLaw for Inbound PSTN calls

[Kasiraman S]

Hi All,

I have a setup where I could not force G711 Codec for inbound PSTN calls between GW and IP Phone. Please find the call flow below.

PSTN-->-->[FXO]GW-->--SIP-TRUNK-->-->CUCM-->-->IP Phone

Both GW and IP Phone are using Same Device Pool in CUCM and using a Region "RegionA" and I have selected 64 Kbps(G722, G711) between same RegionA. Please let me know if there is a way to force G711 in GW side. I have already configured the VOIP dial-peer to use codec G711ulaw but not working and it is working fine for outbound call.

Thanks,

Kasi

[Karthik Sivaram]

hi,

1) Press the "?" button on the  IP phone after the call is setup see which codec it shows.

2)Is MTP checked for unchecked on the sip trunk?

3)Is the IP phone running sccp or sip firmware?

4)once the call is set up run  " show voip rtp connections" on the gateway to see the remote and local ip addresses.

5) Run "debug voip ccapi inout "  on the gateway to see why dial peers are used for the call  and see if you have coded the correct dial peer with g711ulaw.

Thanks,

Karthik