RV: [Asterisk-Dev] ADSI over SIP

[alex at pilosoft.com]

On Mon, 11 Jul 2005, Alejandro G wrote:

> > It doesn't really quite work. It works most of the time, but ADSI
> > requires very precise timing which isn't achievable even over LAN with
> > g.711.
> >
> > The "right" way to do this would be to implement a t38-like protocol
> > to transport the BPSK datastream out of band, but its quite a bit of
> > work.
> (sorry, correction, I meant FSK not BPSK. Too much wireless work lately
> :)
> 
> There are many ATA's with fax pass-tru G711 with no echo cancel and no
> vad, you mean that also in that case the channel could not transmit the
> 1200 FSK correctly?
Correct. It'll work most of time, but not all the time. 
http://www.soft-switch.org/foip.html

timing slips will kill FSK, just like they will kill fax. 

-alex