Virtual Modem for VoIP

Discussion in 'VOIP' started by donfanning, Mar 11, 2005.

  1. donfanning

    donfanning Guest

    Does anyone know of a virtual modem that uses the sound card for VoIP
    donfanning, Mar 11, 2005
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  2. donfanning

    Pepperoni Guest

    Yes there are many software aps for voip.
    Xten and SJLabs are the most popular (IMO) I prefer the SJ product for
    ease of configuration and sound quality.
    Both of these products are used by the major providers and supplied free.

    Another good ap is from Glophone.

    Yahoo Messenger is voice and voip capable with good sound quality.

    You will need to purchase minutes for full "anyphone" use, but most programs
    are free peer-to-peer.

    Pepperoni, Mar 11, 2005
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  3. Is there a simple way to create new profiles for the SJ ? From what I can
    see, the only choice appears to be to download canned profiles for various
    providers, without the ability to change e.g. registrar or outboud proxy.
    The Xten models, on the othe hand, are fully configurable.

    Enzo Michelangeli, Mar 11, 2005
  4. donfanning

    Pepperoni Guest

    Check the user manual.

    I used a profile with no problem. The XTen, on the other hand, had a bug
    that refused to accept the password, and I had to manually configure between
    the password prompt popping up repeatedly.

    I *do* know that the SJ will hold multiple profiles. not sure how I did
    that. (it's been a while.)
    Pepperoni, Mar 11, 2005
  5. donfanning

    donfanning Guest

    I think you're missing my point. The idea is to use existing VoIP
    systems in a different way. For instance, back in the day, IBM had
    these MWave modems that were a general purpose DSP chip that doubled as
    a sound card and a modem. I was hoping someone knew of an application
    that would take my soundcard and do the same thing over VoIP. Hence
    eliminating the need to route a modem through an ATA just to go back
    over the wire. Within the guts of the machine so to speak.
    donfanning, Mar 12, 2005
  6. donfanning

    Rick Merrill Guest

    You do not make sense because a "modem" is a modulator-demodulator and
    an ATA is a modem too!
    Rick Merrill, Mar 12, 2005
  7. donfanning

    Miguel Cruz Guest

    I for one am having a really hard time grasping what it is exactly that
    you're trying to achieve. Maybe you could lay it out in really simple terms?

    Who are you trying to communicate with?

    What hardware do you want to use?

    What hardware do you refuse to use?

    Miguel Cruz, Mar 12, 2005
  8. donfanning

    Ian Guest

    Perhaps it might help if you say what you want to achieve.

    Are you wanting a system of making dialup modem calls using voip lines?
    I think this is what you are after but you dont seem too clear.
    There are loads of virtual modems and com redirectors avalible
    whether one will do what you want I dont know.

    Ian, Mar 12, 2005
  9. donfanning

    wkearney99 Guest

    That doesn't make sense. Voip works by encoding audio into IP packets,
    sending it over the wire and decoding it back into audio. Any sound card in
    a PC can be used by software Voip phone software. It's the getting onto an
    IP network that requires ethernet and no DSP 'cards' will do this (and why
    should they considering how cheap an ethernet chipset is these days). If
    you want to use a laptop that has no ethernet connection and use a dial-up
    modem you can. It'll be slow as all get-out and the sound quality will
    suffer. A software Voip phone listening via the sound portion of the Mwave
    chip and then dialed out via the modem would work, albeit at pretty poor
    sound quality levels due to the slow transmission speeds of the modem.

    In most situations you don't use a modem into an ATA. You use the
    computer's own ethernet connection to make the call. If you've got an ATA
    working then you already have ethernet and, well, it'd be silly to have a
    computer dial into it!

    Or you're asking the wrong question based on wrong assumptions.
    wkearney99, Mar 12, 2005
  10. If you are looking for an FXO interface, able to drive an analog telephone
    line, sense ringing signals, dial DTMF tones and send/receive digitized
    voice, most so-called "Winmodems" have the necessary hardware. For two
    models, one based on the Motorola SM56 chipset and one on the Intel 537
    (a.k.a. Ambient MD3200) plus TigerJet PCI interface, Digium provides
    software drivers for Asterisk and for a while was reselling them rebranded
    as, respectively, X100P and X101P. See e.g. the thread at:;action=display;num=1078366537;start=1#1

    For other models of Winmodems you are on your own; I suspect that it
    wouldn't be that difficult to modify the Digium drivers having sufficient
    hardware documentation.

    Enzo Michelangeli, Mar 13, 2005
  11. donfanning

    donfanning Guest

    I want to communicate to another BBS or FAX system over VoIP without
    relying on an ATA. This should be possible with a soundcard or a DSP
    which a soundcard is anyways.
    donfanning, Mar 14, 2005
  12. donfanning

    donfanning Guest

    The virtual modems out there are for translating COM/Serial
    communications to IP traffic. Not VoIP traffic because it needs to
    refeed over the POTS network. I know exactly what I'm looking for and
    there is nothing on google like this.
    donfanning, Mar 14, 2005
  13. donfanning

    donfanning Guest

    You're missing the point entirely.

    Speaking purely in hardware:
    The IBM Mwave is a general purpose DSP for desktop and laptop
    The system programs the DSP to either be a sound card or a modem but
    not both. The circuitry routes it appropriately to an Telephone
    Interface or Soundcard ports.

    No I'm not talking about using the ethernet card as a modem. Kinda
    pointless since it uses IP. What I'm talking about is using the
    soundcard to belch out the beeps and screeches that a modem
    communicates with into a VoIP channel and spit out on the far side's
    modem/fax through POTS connection on their end (not mine as I want the
    software to do it).

    And in your last case, your absolutely wrong. If you want to use a fax
    or modem, you at this time would connect it into the ATA and the call
    is routed over VoIP to the destination. That is NOT what a ethernet
    card is for.
    donfanning, Mar 14, 2005
  14. donfanning

    donfanning Guest

    Can't be a winmodem although it works on the same premise. A winmodem
    uses a GP DSP with telephone connections attached to the DSP. However,
    the problem is that the DSP only talks to the telephone interface, not
    the soundcard ergo does not work... unless you know of a way to reroute
    a modem back into a soundcard.

    I'm speaking entirely in software... like a voice changer but emulating
    DTMF and even 24/96 baud would suffice to start (slow but a start.)
    donfanning, Mar 14, 2005
  15. donfanning

    donfanning Guest

    A modem modulates and demodulates digital signals to a telephone
    An ATA converts telephone signals into a digital packet for IP
    Neither is the same. That is what the salesman tells you but not how
    it really works.
    donfanning, Mar 14, 2005
  16. donfanning

    donfanning Guest

    An ATA is not a modem. It simply translate Telephone Line Signal to a
    digital packet for VoIP transmission.
    donfanning, Mar 14, 2005
  17. donfanning

    Miguel Cruz Guest

    There is not a lot of tolerance for erratic timing on the analog side of a
    modem connection. VoIP technology is really optimized around the particular
    flavors of tolerance that humans - and not modems - have for lossy
    transmission. You will be fighting an uphill battle. I'd be surprised if you
    could get this working at 9600bps.

    Why not instead just use the remote modem's native modemming powers and pipe
    the serial data over TCP/IP? It's easy, it's reliable, and there's lots of
    software for it.

    Miguel Cruz, Mar 14, 2005
  18. donfanning

    Kyler Laird Guest

    You just want to use the soundcard for the DSP, right? That's because
    your host machine is not fast enough to run the CODEC or is there
    another issue? (You're not thinking of connecting anything to the
    sound card, are you?)

    Kyler Laird, Mar 14, 2005
  19. donfanning

    Kyler Laird Guest

    Yes, of course. A modem modulates and demodulates data between analog
    and digital representations and an ATA...uh...wait...tell me the
    difference again?

    Kyler Laird, Mar 14, 2005
  20. donfanning

    wkearney99 Guest

    You're missing the point entirely.

    If that's the case then it's only because of your descriptions of the

    What's the fixation on the MWave and DSPs? While chips of it's nature have
    a range of features not all of them are worth bothering with. Especially
    given the incredibly low cost of ready-made VOIP devices.

    Just what is it you want to do? What source of audio and what destination?
    You're mixing examples and I'm certainly correct in what I posted. It's
    apparent you're not effectively describing what you want to do. Given how
    you've described it thus far, however, it seems like a waste of time and
    wkearney99, Mar 14, 2005
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