[Asterisk-Users] Pass-thru port on X100P Clone

[Rich Adamson]

> > Ok I already have a Cisco ATA-186 running SIP firmware, can I do dial-up
> > through this? 
> > 
> You can try but I doubt that it'll work; You'll probably just get a
> lot of echo-related problems via the X100P.  A modem/fax connection
> would be more sensitive to echo and call quality than a voice call.
> 
> As I understand it, the SPA-3000 can provide a direct connection from
> its FXS to its FXO, which should avoid this sort of problem.  I'll be
> getting one to replace my home X101P very soon, so I'll know more then.

The spa-3000 only direct connects between the fxs and fxo ports when
power is removed from the box, or when the ethernet cable is disconnected.
Otherwise, fxs -> fxo is using the default codec (g711 unless changed).

In either case (ata186 or spa3000) the codec will limit the speed of
any modem call through it, and the exact speed obtained will be highly
dependent on specific implementations.