use of 56 Kbps modem in 22 Kbps telephone line - Microsoft Windows

This is a discussion on use of 56 Kbps modem in 22 Kbps telephone line - Microsoft Windows ; sir, I heard that telephone line can support a maximum data rate of 22 Kbps then what's the use of having 56bKbps modem. Please help me...

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Thread: use of 56 Kbps modem in 22 Kbps telephone line

  1. use of 56 Kbps modem in 22 Kbps telephone line

    sir,
    I heard that telephone line can support a maximum data rate of 22
    Kbps then what's the use of having 56bKbps modem.
    Please help me

  2. Re: use of 56 Kbps modem in 22 Kbps telephone line

    thegreatkarthik@yahoo.co.in (karthikeyan) wrote:
    >sir,
    > I heard that telephone line can support a maximum data rate of 22
    >Kbps then what's the use of having 56bKbps modem.
    >Please help me


    What you heard is not true. Simple as that.

    --
    Floyd L. Davidson
    Ukpeagvik (Barrow, Alaska) floyd@barrow.com

  3. Re: use of 56 Kbps modem in 22 Kbps telephone line

    On Thu, 03 Jun 2004 04:53:29 -0800, Floyd L. Davidson staggered into the
    Black Sun and said:
    > thegreatkarthik@yahoo.co.in (karthikeyan) wrote:
    >>I heard that telephone line can support a maximum data rate of 22 Kbps
    >>then what's the use of having 56bKbps modem.

    > What you heard is not true. Simple as that.


    The OP's in India. The telephone company in India makes Brutish Telecom
    look competent. A marginal-quality telephone line might only be able to
    take 22 kbps.

    I'll bet karthikeyan was confused by something he read about the
    difference in upload/download rates with a 56K modem. With an analog
    phone line and a regular modem, the fastest you can upload data is 33.6
    kbps. You can download data at 56 kbps (if the phone line is up to the
    job) because your ISP has banks of expensive digitally-connected modems
    at their end of the phone line. Google "56K Shannon's Law modem" for
    more information on this topic.

    --
    Matt G|There is no Darkness in Eternity/But only Light too dim for us to see
    Brainbench MVP for Linux Admin / mail: TRAP + SPAN don't belong
    http://www.brainbench.com / Hire me!
    -----------------------------/ http://crow202.dyndns.org/~mhgraham/resume

  4. Re: use of 56 Kbps modem in 22 Kbps telephone line

    Dances With Crows wrote:

    > On Thu, 03 Jun 2004 04:53:29 -0800, Floyd L. Davidson staggered into the
    > Black Sun and said:
    >> thegreatkarthik@yahoo.co.in (karthikeyan) wrote:
    >>>I heard that telephone line can support a maximum data rate of 22 Kbps
    >>>then what's the use of having 56bKbps modem.

    >> What you heard is not true. Simple as that.

    >
    > The OP's in India. The telephone company in India makes Brutish Telecom
    > look competent. A marginal-quality telephone line might only be able to
    > take 22 kbps.
    >
    > I'll bet karthikeyan was confused by something he read about the
    > difference in upload/download rates with a 56K modem. With an analog
    > phone line and a regular modem, the fastest you can upload data is 33.6
    > kbps. You can download data at 56 kbps (if the phone line is up to the
    > job) because your ISP has banks of expensive digitally-connected modems
    > at their end of the phone line. Google "56K Shannon's Law modem" for
    > more information on this topic.


    Actually, with V.92, the 33,600 bps upstream limit is no longer correct. V.92
    supports upload rates of up to 48,000 bps.

  5. Re: use of 56 Kbps modem in 22 Kbps telephone line

    Dances With Crows wrote:
    >On Thu, 03 Jun 2004 04:53:29 -0800, Floyd L. Davidson staggered into the
    >Black Sun and said:
    >> thegreatkarthik@yahoo.co.in (karthikeyan) wrote:
    >>>I heard that telephone line can support a maximum data rate of 22 Kbps
    >>>then what's the use of having 56bKbps modem.

    >> What you heard is not true. Simple as that.

    >
    >The OP's in India. The telephone company in India makes Brutish Telecom
    >look competent. A marginal-quality telephone line might only be able to
    >take 22 kbps.


    Some lines in the US might only support 14.4Kbps, but that doesn't
    change the answer's correctness.

    The minimum data rate that a telephone line in the US (and
    virtually everywhere else too) is specified at is 14.4Kbps (a
    v.32bis modem should work at that rate), and the maximum is 64
    Kbps simply because a DS0 channel is 64Kbps, and virtually all
    digital telephone switching systems in use today actually switch
    DS0 channels.

    >I'll bet karthikeyan was confused by something he read about the
    >difference in upload/download rates with a 56K modem. With an analog
    >phone line and a regular modem, the fastest you can upload data is 33.6
    >kbps. You can download data at 56 kbps (if the phone line is up to the
    >job) because your ISP has banks of expensive digitally-connected modems
    >at their end of the phone line. Google "56K Shannon's Law modem" for
    >more information on this topic.


    Heh heh... yeah sure, and then spend the next decade trying to
    understand how Shannon applies to *your* phone line!

    In fact (for example) your phone line is a very different
    "channel", for Shannon's purposes, depending on whether you use
    a v.34 or a v.90 modem. And of course, with a v.90 modem the
    uplink is actually v.34... which is why it has a lower data
    rate (and in fact, Shannon's Law says it can't get much faster
    than it actually does, simply because it uses a "channel" that
    includes a quasi analog link provided by a PCM digitial
    circuit). V.90 of course is fully digital, and does not use
    that analog channel.

    --
    Floyd L. Davidson
    Ukpeagvik (Barrow, Alaska) floyd@barrow.com

  6. Re: use of 56 Kbps modem in 22 Kbps telephone line

    thegreatkarthik@yahoo.co.in (karthikeyan) wrote in message news:...
    > sir,
    > I heard that telephone line can support a maximum data rate of 22
    > Kbps then what's the use of having 56bKbps modem.
    > Please help me


    hmm... Actually...
    different phone lines can support higher and lower speeds. For
    instance, when I had dial-up here, it would usually connect at 28.8 or
    21.6 kbps (granted it never transferred at that rate, except once,
    when i was downloading a... umm... video ) The thing is the
    connection speed is only as good as the wiring. like using ethernet
    cable thats rated for 10Mbps on a 100Mbps network. Another key factor
    is how many people are using the line in your neighborhood. If
    everyone and their mother tried to connect to the internet through
    dialup at the same time, there would be no way in hell anyone would
    get anything resembling good connection or download speed. that last
    reason is the reason why my 3Mbps Cable provider cant provide at
    3Mbps.

    To know networking is to know the phone/dialup system

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