[asterisk-users] Fax Machine Options

[Andreas van dem Helge]

On Tue, May 20, 2008 at 12:23 AM, Lee Howard <faxguy at howardsilvan.com> wrote:
> Andreas van dem Helge wrote:
>> Cisco gateway with T.38 support. That's the only real way to do faxing
>> through asterisk.
>
> Although this statement has marginally more truth to it given the
> SIP-only context that the original poster provided, it is still
> substantially inaccurate.

So, mr accurate, please tell us what is the best way to fax via
Asterisk. Keep in mind you can't always control the latency between
the endpoint and the asterisk machine/media gateway (yes, I know SIP
to asterisk on the same VLAN + send the call via PRI works pretty
well).

And how do we know he is using SIP only? He asked about the IAXy!

> There are several ways to do T.38 other than with a Cisco gateway.  Now,
> if you meant that T.38 is the only way in the SIP-only context (and not
> specifically Cisco-branded T.38) then that has significantly more
> accuracy to it.

Doesn't have to be Cisco. But there is no Asterisk T38Gateway.... so
either way you need to buy a 3rd party gateway (or use a service that
supports it... check out www.gafachi.com) Audiocodes we can take off
the list because the violate the GPL so next down my list is Cisco.
But any SIP-compliant T.38 gateway will work.

> However, if by *real* you also mean *reliable* then be aware that T.38
> over SIP/UDP has an inherent weakness due to the medium that make it, in
> my experience, significantly less-reliable than simply having a fax
> machine hooked up to a traditional analog line.

Yes but significantly the most reliable way to fax at the moment via
"VoiP"... well you have that magic answer but I haven't heard it yet.
Honestly if the OP is using the phones voip-only and can make calls
and understand the remote party and be understood there should be no
issues. The problem is even in an environment where voice quality is
perceived very well faxing could still be an issue. If you have an
issue where your t38 calls can't complete due to packet loss, latency
or other such issues I doubt you can make an intelligible phone call.

> When my clients come to me with the same issue I generally do not push
> them into a corner with T.38.  In almost all cases they find that it is
> worth the $20-50 monthly for the analog fax line... and if that expense
> is too much then the on-line fax service provider is an easy recommendation.

You're not my client and I'm not trying to pressure anyone. What if
they have 500 fax machine spit over 23 locations is keeping phone
lines still cost effective? He's asking on the Asterisk mailing list
regarding faxes so I assume 'get a phone line' isn't an option.

> Note that if you have a fax machine that performs some variant of T.37
> (fax-over-email) and you have an on-line service provider that is
> willing to work with you... then you can rather easily get your fax
> machine faxing through their service.  (Which is yet another option.)

And how many (low cost... not $5000 "copiers") do that?

and to the OP about the hardware, even a cheap grandsteam ATA will
work just fine... that's what I use on my personal fax machine and it
has no issues. I can't recall a time this year a fax has failed. This
is going over the public internet and then also back out to a voip
provider. We do use decent networks but that's about it. No QoS
anywhere down the line.