[asterisk-users] Ast/Hyla/IAX Scalability?

[David Backeberg]

On Sat, Mar 14, 2009 at 12:00 AM, Steve Underwood <steveu at coppice.org> wrote:
> Fully open-to-the-public FAX servers tend to get just get a lot of bad
> calls, many of them wrong numbers, or voice users. FAX servers for

I've definitely seen that, and have been able to either identify the
validity of a caller by CID or by calling the number and confirming a
blast of fax tones.

> clue what kind of failure rate might be expected. You can find a bit
> more about these issues and our results at
> http://www.soft-switch.org/spandsp-soft-fax-performance.html

After reading that, it occurred to me that I'm running SpanDSP 0.0.5
and 0.0.6 seems to have enhancements that may solve the problems I've
been seeing. I'm convinced that it's worth upgrading and seeing if I
can reduce my failure rate.

> Your differing failure rates between using ReceiveFAX and using iaxmodem
> seem to indicate your results relate to issues in your own system,

I think I wasn't very good at setting it up, as I had no experience
with IAX. Likely my fault rather than anything inherently wrong with
the software. There were more moving parts than I was able to get a
handle on, and when I switched to 1.6 and app_fax things 'just
worked'. This is why I keep recommending the 1.6 approach over the 1.4
+ IAX + IAXModem + Hylafax.

> LANs don't loose packets), will have a true failure rate (i.e. a rate of
> calls failing which had the potential to succeed) well below 1%. The

That's consistent with my testing before I set it live.

You mentioned recording faxes. I know how to do that with IAXModem,
but are you familiar with a method for 1.6 and app_fax? I read through
app_fax.c and didn't see any way to send a flag. Is the recording
built into SpanDSP, or is is something IAXModem added on themselves?