Faxing and PCI (was Re: [Asterisk-Users] Digium cards,

[Olivier Krief]

2006/4/18, Doug Lytle <Support at drdos.info>:
>
> iaxmodem is a software modem that uses the IAX protocol and registers to
> Asterisk as an IAX client allowing HylaFAX all the resources of the
> Asterisk PRI or whatever allows connectivity.
>
> Thank you very much for the explaination.

1. Does using iaxmodem imply that, for example, incoming fax calls are
processed that way ?
- PSTN calls are terminated on TDM board (Digium, Sangoma, ...)
- the media flow (G711 as it comes from PSTN) is forwarded without any
modification to the right instance of iaxmodem software process
- iaxmodem process are "managed" by hylafax application but are seen and
identified by Asterisk as IAX softphones (during above mentioned
registration)
- media is processed once, according hylafax config (that often means
forwarded to printer or email), after a single "move" from TDM board to
server processor through PCI bus

2. If it's correct, fax speeds and protocols (V29, G3, ...) are defined by
hylafax and iaxmodem.
So, how do hylafax-iaxmodem speeds and protocols compare with those from a
standard fax machine ?
I mean, if you had bought a new fax machine and had it connected to the
PSTN, would you get a different set of speeds and protocols ?

3. How do iaxmodem and rxfax-txfax DSP functions compare ? Are they using
the same library ? Is there any standard allowing iaxmodem or rxfax-txfax to
benefit from hardware DSP inside TDM board ?

4. How would that scale ? Up to 30 Calls ? Are incoming or outgoing faxes
more demanding ? Any hardware recommended ?

Cheers
Olivier
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.digium.com/pipermail/asterisk-users/attachments/20060418/685d92c2/attachment.htm