[asterisk-users] FAX reliability

[Steve Underwood]

Hi Lee,

Lee Howard wrote:
> Hi Steve,
>
> Steve Underwood wrote:
>> In chan_dahdi.c there is now code that extends the buffering inside 
>> dadhi when a FAX is detected, and puts the buffering back to normal 
>> at the end. This isn't really a cure - its more of a bandaid. 
>> However, I expect it has the desired effect if they have put it into 
>> the trunk code.
>>
>> You need to enable this feature in chan_dahdi.conf.
>>   
>
>> Very interestingly, many people who have problems sending from 
>> app_txfax or app_fax have no problem sending from iaxmodem + HylaFAX. 
>> It seems Asterisk can feed a zaptel/dahdi channel much more reliably 
>> when passing a signal through, than when generating on in an app.
>
> So are the chan_dahdi.c developments mentioned of any practical value 
> to iaxmodem users?
That's a good question, and I have no idea about the answer. Some people 
who have had problems sending from app_txfax say iaxmodem + HylaFAX 
works OK on the same machine. This seems strange, as you might expect a 
problem in scheduling I/O would affect passthrough as well as 
applications. What I don't know is whether they just have a lot less 
trouble with iaxmodem, or they have no trouble at all.

Do you get reports from people who say receive is stable, but transmit 
is not?

Steve