CAC and conference bridges

[Hatem_Hamdi]

Hi all,

I have centralized cucm installation with a central site and two branchs. Every branch has its own IOS Enhanced conference bridge. My two branchs communicate in G.729 between them and using G.711 locally.

I worked without CAC intially and every thing was fine I was able to do G.729 conferences between the two sites without any problem then I implemented CAC and allowed 2 calls only between them. In other terms I fixed the bandwith for 50 kbps for my locations.

Now I am not able to do the following conferencing scenario due to the bandwidth limitaion :

IP Phone Branch 1 to initiate a conference with two IP Phones from branch 2. Is this normal behavour? knowing that when change my locations configuration to allow 3 calls (75 kbps) the conference works.

Best Regards,

Hatem Hamdi,

[Vipul Jindal]

Hatem,

you need to check the location and region setting for confernece bridge with the 2 ip phone from branch 2.

whats the relation set to of region and location.

thanks,

Vipul JIndal

[Gajanan Pande]

Is this Add-on conferencing you mean ? i.e. Phone in Branch 1 calls phone A at branch 2 then presses a conference button & calls phone B in branch 2 & again presses conference button.

GP

[Hatem_Hamdi]

Hi Gajanan,

Actually it is an ad hoc conference as you described.

Best Regards,

[Chris Deren]

So, the conference bridge you are invoking is configured to use Location 1 which is the same location that the IP phone initiating the bridge is using?

Then you are bridging 2 remote phones that are configured to use Location 2? And regions are defined to use G729 between region 1 and region 2?

Is the conference bridge defined to use both codec or are you possibly engaging trnascoder here as well?

Chris

[Hatem_Hamdi]

Hi Chris,

My regions and locations are configured as you described.

The conference bridge is defined to use G.729 only but I don't think that a transcoder will be engaged for the conference because I am using cisco phones so my voice streams will be sent G.729 coded directly from the phone. And I am pretty sure that it is not a matter of g711 being used between the to site for conferencing because the limit i set for the location is 75 kbps which does not allow g711.

Regards

[Chris Deren]

is your HW conference bridge defined with the G729 codec?

Chris

[yahsiel2004]

Hatem,

How are the 2 sites connected via (vpn, mpls etc)? 50 kbps is not suffecient to make 2 calls using g729. Below is a link to Cisco's voice codec bandwidth calculator.

http://tools.cisco.com/Support/VBC/do/CodecCalc1.do

Regards,

Yosh

[Hatem_Hamdi]

hi yosh,

Actually 50 kbps enoguh for two calls and I have done the test. I have a problem only with conferences.

regards

[Chris Deren]

Yes, from CUCM perspective Location configured for 50 K is ok for 2 calls as CUCM assumes 24 kbps per call, in reality this is more depedning on layer 2 overhead.

Not sure why it is behaiving this way, I'd would recommend looking at the logs.

Chirs

[Hatem_Hamdi]

Hi Chris,

Please advise on which logs should I be inspecting.

Best Regards

Hatem

[Hatem_Hamdi]

yes it is

[Dennis Mink]

ccm manager tracelogs tell you which media resources are being invoked and possible errors (use rtmt to obtain them) make sure you get an exact times tamp of your test as these files are big.

If the only thing that has changed is CAC, can you set the bandwidth to unlimited to verify at least that conferencing is still working

Sent from Cisco Technical Support iPhone App

[Hatem_Hamdi]

Thank you I will give it a try.