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100 concurrent calls


I was thinking about 100 concurrent calls and I have used TAC bandwidth computation for this. Based on the computation I need to have a T1 link.

What if I can't afford to get a T1 link and atmost I can only get a 512kbps.

Will it still support 100 concurrent calls or once it consumes the bandwidth succeeding calls will be dropped?

Hope you can answer this.

We need to implement VoIP but I'm still trying to understand it.

Any other advice ot tips is highly appreciated.

best regards,

Pablo Jose

VIP Purple

Re: 100 concurrent calls

Callmanager has a concept of Call Admission Control (CAC) that determines the number of calls allowed on a link based on your Region and Locations configuration. Regions determine the codec used and therefore the bandwidth used per call. Locations determine the total bandwidth available for a given link. When this bandwidth is exceeded, subsequent calls are denied. Without CAC, you could have 100 calls on a 512k link, but the quality of all calls would suffer. Take a look at the following links.

Hope this helps. If so, please rate the post.



Re: 100 concurrent calls

even with the highest compression codec, g.729, over FRF.12, bandwidth required per call is 26.8kbps per call. this would provide for 2 calls per channel.

512k = 8 channels. 8 * 2 = 16 calls simultaneous via FRF.12 (19 max). (ethernet requires 31.2kbps per call in this scenario)

see this link for more "VoIP Per Call Bandwidth Consumption":

as previously stated, for 100 calls required over 512K, CAC is your best bet. not all calls will operate simultaneously but you'll be able to set the parameters of how/what calls get admission.

Community Member

Re: 100 concurrent calls

Thanks a lot for the explanation...

I appreciate all your help.


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