Physical Fax Phone Line

mike-h30
2011-07-31
2013-04-05
  • mike-h30
    mike-h30
    2011-07-31

    One thing I don't understand is how will my current physical fax line be routed to the IAX Modem?  Currently I have my physical fax line plugged into my Multimodem ZPX.  Will I be able to keep my current dedicated physical fax number?  We have had the same fax number for over 5 years and would like to keep it.  Thanks.

    Mike

     
  • Lee Howard
    Lee Howard
    2011-08-01

    You'd use IAXmodem in conjunction with a hardware DAHDI or Zaptel device.  That said, if your ZPX Multimodem is working why ditch it?

     
  • mike-h30
    mike-h30
    2011-08-01

    I would like to move my Linux servers to a virtual environment.  Ideally I would like to run my servers in Virtual Box on a Mac Mini Server.  I am also looking at Xen as another option if I don't go the Mini route.  Right now I am not seeing the ability of the VM's to communicate with a physical fax board on a host machine ( for sure that would be a no go on the Mac Mini).  It was suggested that I turn to IAXModem to solve that problem.

    Mike

     
  • Lee Howard
    Lee Howard
    2011-08-01

    Any IAXmodem solution that does not involve hardware invariably uses network VoIP channels which are unreliable for fax use.  While there are some heavily-controlled environments where I've seen it work, I do not recommend it - especially for what seems to be your motivation here.  Using T.38 (so t38modem) may be a more-reliable solution for your interests, but a lot of that reliability would depend greatly upon the gateway services of the T.38 (probably over SIP) provider.

     
  • mike-h30
    mike-h30
    2011-08-01

    Thanks for your replies.

    "Any IAXmodem solution that does not involve hardware invariably uses network VoIP channels which are unreliable for fax use. "

    It sounds like I definitely want to involve hardware with IAXmodem. 

    1.  Is the hardware you refer to the DAHDI or Zaptel device?  Or is a physical fax board ( ZPX Multimodem) still required with the other hardware (i.e. DAHDI or Zaptel device) for use with IAXModem?

    2.  If the guest machines can communicate with the hardware on the host then an IAXmodem solution will work in a virtual environment, right?

    I need to get up to speed on how the "hardware" works with IAXModem.  Pardon my novice questions but this is new territory for me as I only have experience with setting up Hylfax+ and the ZPX Modem in our small office (5 users).

     
  • Lee Howard
    Lee Howard
    2011-08-01

    If you use IAXmodem you should be using a DAHDI/Zaptel hardware PSTN interface with Asterisk/FreeSWITCH/CallWeaver.

    If you use a hardware modem, such as the Multitech ZPX Multimodem, then you don't need IAXmodem, the PSTN interface, or the soft-PBX (Asterisk).

    I cannot comment on virtual environments as I've never used them myself.  I've heard from plenty of users who have had problems in virtual environments.  I don't know that I've heard from any that use virtual environments reliably for fax.

    IAXmodem is a software modem.  It gets the audio from a network stream from a soft-PBX such as Asterisk.  Conceptually that audio stream could come from anywhere, but because of the way that VoIP channels work that stream must come from the same system on which IAXmodem is running or there is a likely chance that the audio quality will be too poor for fax use.  So the soft-PBX must have a PSTN interface such as a DAHDI/Zaptel card.  This effectively turns IAXmodem and Asterisk into the "fax modem driver" for the PSTN interface… essentially doing the same thing that the ZPX modem does… except with a bunch of voice features added-in.

    I'm having difficulty understanding why, if the ZPX modem works fine, you'd switch to an IAXmodem/Asterisk arrangement.

     
  • mike-h30
    mike-h30
    2011-08-01

    Thanks for the wealth of information!!

    I'm having difficulty understanding why, if the ZPX modem works fine, you'd switch to an IAXmodem/Asterisk arrangement.

    We have replaced all of our client machines from Linux to OSX.  It would be nice to replace our Dell PowerEdge server with a Mac Mini server and have 100% Mac hardware.  All of our business applications are web based (PHP/MYSQL) and have no problem running in a Linux VM ( I prefer LAMP as opposed to MAMP).  Due to the need for us to rely on faxing daily, we need to keep the Dell around because of the ZPX modem.

    Based on your replies, it sounds like I am better off keeping the fax server on a physical machine.  Yes, the ZPX has/is working  great!!