FoIP through Lingo

Discussion in 'VOIP' started by DanG, Apr 3, 2005.

  1. I have limited exposure to T.37 (store and forward), so I can't really
    answer to that question. I guess what happens is that you negotiate in
    realtime with a fax-like entity running on the media gateway that your cable
    box is sent to, and that later your fax is then sent along to another media
    gateway which then negotiates with the fax machine you're sending to. Sort
    of like fax by proxy, with two actual fax calls being placed (one between
    sending fax machine and gateway 1, the ohter between gateway 2 and receiving
    fax machine) - rather than one call between the two fax machines.

    Try to nail them down on what they mean by "FoIP". This typcailly means
    "fax relay" in the business, not just fax over G.711 (which is usually
    called "fax passthrough"). There are other flavors of fax relay that are
    not IP-specific - there is fax over AAL2 (for ATM Links), FRF.11 (for frame
    relay links, largely obsoloete) and other proprietary methods. However,
    what I believe that they're doing is blowing smoke up your rear end. I bet
    they just sense the tones on the line that are unique to fax, and switch
    your call over from a voice-specific codec (like G.729ab) to G.711. If this
    is the case, as I've said before, there is no reason you should not be ablt
    to use your PC w/ modem at 14400bps speed - unless their network sucks.

    Ask them this specifically: "Does your fax solution implement true fax relay
    (FoP), or is it simply fax passthrough, with G.711 carrying the fax

    James Calivar, Apr 7, 2005
    1. Advertisements

  2. DanG

    DanG Guest

    Okay, I talked to Lingo again. No new information, though. The techie
    just reiterated (in more detail) what they said before: you have to use
    a fax machine (not a PC) with a 14400 modem, and they don't support

    I asked about fax relay and fax passthru, and was told that they can do
    either. I asked if I need to do anything to tell the fax machine which
    protocol to use, and the techie said no.

    I'll have to see if I can borrow a machine.
    DanG, Apr 8, 2005
    1. Advertisements

  3. Yes, see if you can borrow a fax machine. I cannot for the life of me
    figure out why a "real" fax machine would work when a PC-based fax modem
    would not, though. They are functionally identical.

    When the tech says that "they can do either" fax relay or fax passthrough -
    but they DON'T support T.38 - then unless they're using a proprietary fax
    relay solution I haven't to foggiest notion of what he is talking about. On
    IP networks, today's fax relay is T.38. Older gateway solutions (for
    example, some Cisco boxes) fielded proprieteary fax relay software, but that
    requires having an identical box on both ends, which cannot be guaranteed.
    I think the techie is misinformed, and it sounds as if they are all just
    trained to parrot back the same lines to customers.

    let's hear what happens with the "real" fax machine.

    James Calivar, Apr 8, 2005
  4. DanG

    DanG Guest

    Sorry. No news yet. I thought I'd borrow a machine from the office
    across the street from me, but apparently they only have a huge floor
    model. They suggested that I buy one, then return it th next day, but
    not fair to the store. I even thought I could rent one for a day, but
    can't find any place that rents computer equipment around here.

    The saga continues...
    DanG, Apr 11, 2005
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.