Question on codec

[alanhow2007]

Hi,

Would like to know the following,

When intially the call has set up, by default from the pabx travel via to the router gateway (by isdn or e&m trunk) is it in codec G.711 ?

Have done a monitor on our router gateway it shows as follow

0/1/1:15.1      g711ulaw   n  S_SETUP_INDICATED     S_TSP_INCALL

Only when the call going into the router gateway after going through the configuration it shows as follow

0/1/1:15.1      g729r8     n  S_ALERTING            S_TSP_INCALL

Is there anyway to configure in such that the set up will be g729 instead in the router gateway setting ?

Thank you

[Volodymyr Morskyy]

It seems like your call have no dial-peer to match and then default dial-peer is matched (it has g729 in its configuration).

[alanhow2007]

Dial-peer has been set right as follow

voice class codec 1
codec preference 1 g729r8
!

!

dial-peer voice 2002 voip
translation-profile outgoing Append8
preference 3
destination-pattern .T
progress_ind setup enable 3
progress_ind progress enable 8
translate-outgoing calling 2
session target ipv4:x.x.x.x
incoming called-number .T
dtmf-relay h245-alphanumeric
voice-class codec 1
fax rate 7200 bytes 48
ip qos dscp af21 signaling
no vad

[Aaron Harrison]

Hi

Presumably the router is assuming G711 prior to the codec negotiation... similar to the way that it works when you run a call through a GK:

http://www.cisco.com/en/US/tech/tk1077/technologies_white_paper09186a00800c5f67.shtml

Initially it uses G711 bandwidth, and then negotiates whatever the low bit rate codec is.

Is this causing you a problem?

Aaron