iLBC codec packetization issue

[hardik_33]

I have video call between two phone as below

9971 -- CME --- CUBE ----CUCM --- 9971   (delay offer)

call from cme end to CUCM end works (video and audio) h264 and iLBC

call from CUCM end to cme end connect(video works) but no audio (can see on phone both ends Rcvr discarded) due to cucm end doing 30ms and CME end doing 20ms

Debugs on CUBE shows CME send offer with 30ms but CUBE send offer to CUCM without any ptime ?

CUBE has codec transparent on both ends.

Thanks

[Randall White]

Try asymmetric payload full under voice service voip > sip.

Do this on both CUBE and CME.

[Irshad Mohammed Hussain]

use codec ilbc mode 30 at your CME End

[pkinane]

I had the same issue. I resolved it three ways.

The least preferred way:

Go to the inbound and outbound dial-peers on the CUBE. On the dial-peer enter the command

codec ilbc mode #

where # is the lower of the two ptime values. In this instance 20 (from CME side) is lower so the command for this scenario is

codec ilbc mode 20

A little better way:

We can tell CUBE to passthru the SDP. I recommend doing it on the dial-peer instead of doing it globally:

CUBE#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
CUBE(config)#dial-peer voice <tag>
CUBE(config-dial-peer)#voice-class sip pass-thru content sdp
CUBE(config-dial-peer)#end
CUBE#wr
Building configuration...

[OK]
CUBE#

Even better way:

Create a voice class codec and have one of the codec preferences be ilbc mode 20

conf t

voice class codec 1

cod pref 1 g711u

cod pref 2 ilbc mode 20

Then apply the voice-class codec 1 to your dial-peers as needed.