Problem of bandwith

hi everybody;
do you think that i can get a clear call with an adsl line bandwith of 128kb/64kb ?
how many concurrent calls can be done with that bandwith?
wich bandwith do you think is enough to make calls on an E1 ?
thanks for your reply.

If you’ve configureed correctly, and you have no other use of the link (web browsing or email or anything like that) you may get 1 call across the link.

I wouldn’t expect more.

its possible, but you will need to use a lower-bitrate codec like GSM, iLBC or G.729. G.711 ulaw/alaw are out of the question. Also, if you have ANYTHING else using the link you will need a QoS control of some kind. Possibly a router with good QoS. You will also (even with G.729) get only 2-3 concurrant calls absolute tops.

To make an E1 worth of calls you need about 2 megabits (an e1 worth of bandwidth). However, by using a low-bit codec you can shrink that, using GSM codec you can do it with under 1mbit.