Unable to negotiate iLBC with Cisco 9971

[inderpreetsingh23]

Hello Everyone,

I have two sites: HQ and Site C. I have one Cisco 9971 at each site. HQ site is having CUCM 9.1.2 whereas Site C is CME. HQ router is configured as CUBE. The two phones  talk to each other via CUBE. Whenever I make a call between two phones the video codec negotiated is H.264 and audio codec used is G.729. I

But the call doesn't work when I set the audio to iLBC. I have used voice class codec also but no success.

Please help me with this.

Running config of both the routers is attached. 

Debug ccsip messages on Site C router also attached.

Thanks

[Ayodeji Okanlawon · Accepted solution]

There is no debug attached! But I think I know whats going on. Without seeing your configuration or debugs its impossible to know accurately what is going on..

Two things..

1. The region between your phone and cube sip trunk should be set to ilbc

2. the voice class codec on sc ccme should be like this..

voice class cod 1

cod pref 1 ilbc mode 30 (you cant have any other codec on the voice class codec..this is a bug with ccme and ilbc)

(CCME by default uses 20ms packetization mode and cucm uses 30ms, so for this to work you need to set ccme to use packetization mode 30ms)

3. The dial-peer on cubes can be configured in different ways..

3a codec transparent

3b. voice class codec 1

cod pref 1 ilbc

cod pref 2 g729r

Hope this helps

[inderpreetsingh23]

Hi Ayodeji,

I have uploaded the files again. 

The region between phone and CUBE has been set to iLBC.

Debugs will be able to help more.

[Ayodeji Okanlawon]

Deleted

[inderpreetsingh23]

Hi Ayodeji,

It worked...

Thanks for the help