I have the following requirement: ISP with a single E1 line needs to accept incoming dial-up calls and use Asterisk to place/receive voice calls with the same E1. Available hardware is Cisco AS5300 (RAS with modem cards) and Asterisk with TDM405. From what I read about the Cisco, it can't be used connected directly to the outside E1 with a second E1 interface between Cisco and Asterisk to bypass all calls that aren't the dial up number to Asterisk, as well as allowing Asterisk to dial out using the E1. If anybody can show me how this can be done on the Cisco side, I'll gladly pay US$ 200 via Paypal after I verify that it works. Just to make sure, this config would be: ISDN E1->Cisco AS5300 (with a quad E1 card)->Asterisk with single E1 card And what I'm willing to pay is for the Cisco config to achieve that. Asterisk needs to be able to receive incoming calls and place outgoing calls, with the Cisco only answering calls to a single number out of the 100 phone numbers the E1 has. The remaining option is: ISDN E1->Asterisk with TDM400P card->Cisco AS5300 There my concern is frame slips, causing performance degradation for the dial-up calls. I have a Intel motherboard with Pentium 4 to setup Asterisk with, so I think I'm using the highest spec MoBo to handle the TDM400P. On this last option, has anybody been able to have such a system working reliably, and for that I mean, being able to do Fax or Data calls with Asterisk in the middle, and on the other end either a Digital RAS, or a PBX with Fax machine/dial-up users. The criteria for dial-up would be to successfully deal with V.90 calls at rates higher than 40 kbps, and no noticeable degradation from having the E1/T1 line conected directly to the PBX or the RAS box. Thanks in advance, Marcelo Pacheco M2J Comunica??es e Inform?tica Brazil - Vitoria-ES