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New Member

Voice bandwidth over T1 (g.720 and CRTP)

I am planning on running 80 concurrent voice calls over a dedicated T1 using g.729 and cRTP. These are agents that are up all the time. Based on my calculations 80 agents will us 960K BW. 12K per call x 80 agents. I will be using 2621M routers to terminate the T1s. My questions are;

Is my math correct on BW utilization of 960K? No data on this T1. Just voice.

Is a 2621XM suffecient for 80 calls doing cRTP or should I move up to a bigger box?

New Member

Re: Voice bandwidth over T1 (g.720 and CRTP)

Case study by Avaya using Cisco 2621

I guess 12K per call is fine.

Hope this helps.


New Member

Re: Voice bandwidth over T1 (g.720 and CRTP)

You won't get 80 concurrent calls on a 2621xm. Cisco

state 60 but I would think that with cRTP it'll be a lot less. I'd be looking at something bigger.

New Member

Re: Voice bandwidth over T1 (g.720 and CRTP)

Thanks for the feedback. I'm thinking the 60 calls their talking about are PSTN type calls. The max Digital voice port density you can only get is a 2 port NMHDV network module (2 PRIs) which would net you 60 calls max.

I also think it makes sense to move up. I'm going with the 3725 or 3745.