I'm looking at setting up an ISDN internet service for someone, and
she'd like to be able to do VoIP. The modem (230kbps serial and 2 POTS
ports) you get from the ISP can do DVO (Dynamic Voice Override) where
you can be online at 128kbits/sec (2 channels), but if a voice call is
detected (call waiting signalled via the D channel I guess) or if you
want to make a call out, one of the channels drops to be used for voice,
leaving the data at 64kbps. When the voice call finishes, the modem goes
back up to 128k.
Has anyone configured a system with Asterisk and a BRI adapter to do the
same thing for when you aren't making a VoIP call? (calls to mobiles are
normally cheaper via PSTN than VoIP on the cheaper plans from what I've
seen in Australia). I could also use a SPA3000 or something in line with
the voice port on the modem, but having asterisk do it all would be
quite nice.
As usual, any and all comments appreciated!
Thanks
James
