[Asterisk-Users] * and Fax

[Lee Howard]

On 2004.09.29 06:55 slwatts at winckworths.co.uk wrote:

> Ideally a voipfax modem device is needed (looks
> like
> a modem, behaves like a modem but works on a sip channel and not 
 
> isdn/analog line) then asterisk can treat it like any other extension,
> and
> hylafax can treat it like a modem.
 


I think that there are three nearly-ideal solutions:

1) have some Asterisk module provide a pseudo-modem device that 
Asterisk can use as an extension.  HylaFAX can treat that pseudo-modem 
device as a modem.  I believe that Steve Underwood, the spandsp author, 
was working on a solution of this fashion.

2) get Asterisk capable of properly working with t38modem.  In this 
case, t38modem would be the extension.

3) create a T.38 channel-driver for Asterisk and create one for 
HylaFAX.  In this way, Asterisk could use HylaFAX's driver as an 
extension.  This would give HylaFAX better control of the faxing than 
the Class 1 interface can give it, but it also is the least likely to 
happen anytime soon.

I think that #1 or #2 are the most likely to be available any time 
soon.  Until then, additional hardware must be used to get Asterisk and 
HylaFAX working together.  In the case of analog an ATA device must 
generally be used, and for some reason this arrangement seems to 
generate a lot of interference.  In the case of digital T1/E1, which 
arrangement doesn't seem to suffer the analog-ATA interference, you've 
got to have an additional T1/E1 port to interface with the T1/E1 card 
driven by HylaFAX.  In any of the solutions above not only is this 
additional hardware not required, but there will be no modem hardware 
required specifically for HylaFAX.

I agree with you that attempting to recreate functionality and 
facilities for Asterisk that are already present in HylaFAX is 
misguided when that effort could be better-spent getting one of 1-3 
going.

Lee.