I have a couple of capacity related questions for which I am hoping to find answers (or at least hints) derived from real-world experience. asterisk as a "trunking gateway"; bunch of sip phones in location one need to access other non-* sip PBX device in location two over constrained bandwidth. I can't replace the existing SIP phones or the other SIP device. I'm considering using * boxes at each end of the WAN circuit to pack all of the individual SIP sessions into an IAX2 trunk and then unpack them back into SIP at the far end. Assuming for the moment G.711 all the way thru, so no codec conversions anywhere, how many simultaneous sessions should I reasonably expect to get through a typical single CPU P4 3.2ghz box? Then as an option, if I wanted to compress the SIP G.711 calls into say IAX2-GSM trunks, how would that impact the channels per box number? (well, I know it's going to go down, any hints how much?) Any thoughts? Regards, -Dorn