[Asterisk-Users] Small office requirements - Can this be done?

[Steve Kennedy]

On Tue, Mar 02, 2004 at 10:04:23AM +0000, WipeOut wrote:

> On the UK DSL using G.711 you should easily get 2 concurrect calls, 
> G.711 uses about 84k(incl overhead) in each direction, so 2 calls would 
> be 168K (of the 256k)

It all to do with running IP/ATM (BT's ADSL is all over ATM) and how the
multiplexing etc is done over the ATM network, such that with a 256K
upstream you only really get 1/4 of the bandwidth for TOLL GRADE
service. That doesn't mean you cant get more voice channels out of it,
you can, but you'll start suffering on dropped packets etc.

I'm sure some more knowledgable person can go into the maths behind
IP/ATM and bitstuffing techniques to maintain latency and jitter.


Steve

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