Concurrent Calls vs Minutes per Month

[kleclaireultratek]

I've been asked to spec out a gateway to terminate about 30,000 minutes a month. Since this traffic is coming in voip and being converted to TDM I know my max # concurrent calls is limited by the tdm side of the gateway.

How do I correlate 30,000 minutes a month to the number of channels I need available for the tdm side?

[paolo bevilacqua]

Sorry, you can't really establish how many channels without knowing the average call length ad distribution (erlang computations).

Depending on that you could do well with two channels or have trouble with twelve.

[kleclaireultratek]

Yeah, Ive seen the erlang computations and was hoping there was a decent rule of thumb to go by .

Thanks.

[paolo bevilacqua]

VoIP rule of thumb: If it's cheap, get much of of it and live easily

If expensive, get little and find a way to make things work anyway.

Didn't wanted to sound dumb, but really it's like that.