[Asterisk-Users] Dumb Question

[Marsson]

Hello everyone... i have just found out about asterisk and before doing any 
purchase of hardware i would like to know if i figured right about the use 
that i'm planning on it.
first of all i woul like to state that this instalation must be REALLY 
innexpensive. I've got two companies in different cities and would like to 
connect their PBX, I was planning to connect them through 2 asterisk boxes, 
whith only one iax channel, so that i could make local calls to the other 
city, using my default internet connection (256k DSL on both) could i do that 
with ease and relly low costs??
Thanks in advance