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CIPC Drops Calls on Connect

User has IP Communicator over AnyConnect VPN. Calls between extensions work fine, seems to work if user places call to outside, but when a call comes in when the user attempts to answer, the call is dropped.

He thinks it happens mostly with internatinal calls but it did happen when I tried calling on my cell phone.


Have u tried disabling G729 ?

Open CIPC, Right Click, Preferences, Optimize for Low BW.

Thank you, but yes. :(

Thanks - I've been searching for 3 days for a resolution and found the codec on the CIPC to be the issue.

CUCM 4.2

ASA 8.0.4

AnyConnect VPN 2.2

CIPC 7.0.2

Internal users could make 3 or more way conferences with no issue, both on-net (IP to IP phone/softphone) and external through GW (PSTN).

Remote users on AnyConnect VPN coming through ASA FW could set up 2 - way call but when trying to conference in a 3rd party, the initiating caller would receive fast busy tone and drop out of the conference.

MY CUCM is set to G.711 internal and G.729 across my WAN (we use intercluster trunks to global CUCM clusters).

Once I changed the CIPC preferences to un-check "optimise for low bandwidth" I could establish multiple way calls from the CIPC devices.

Now I need to understand the impact of changing the CUCM to force a standard G. codec across internal (on-net & trunk) and external (CIPC).

Any suggestions?

I somehow missed this reply. I unchecked the "optimize..." option and calls are now being connected both ways!

I'll have to notify the end user about this and monitor what affect this has on call quality.

Un-checking will force CIPC users to use G.711 which is 64Kbps as opposed to G.729 which is 8kbps.

Users on low BW or unreliable connections will notice jitter and packet loss. The only option then is to configure a transcoder on your gateway (if you use this)

Good luck!

Thanks for the info. That doesn't seem a severe trade-off. Who really has low BW anymore anyway? Unreliable, I can see, but those times I think are intermittant.


Are you using CME or CUCM?

Sorry, that would help, eh?

CCM 4.2(3)

CIPC 2.1.4

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