CAT 3 UTP cables capable of 100 Mb/s - TCP-IP

This is a discussion on CAT 3 UTP cables capable of 100 Mb/s - TCP-IP ; hiya 100Base-T4 was developed to allow 10BaseT networks to be upgraded to 100-Mbps operation without requiring existing four-pair CAT 3 UTP cables to be replaced with the newer Category 5 cables. Now if cables of category 3 are somehow able ...

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Thread: CAT 3 UTP cables capable of 100 Mb/s

  1. CAT 3 UTP cables capable of 100 Mb/s

    hiya

    100Base-T4 was developed to allow 10BaseT networks to be upgraded to
    100-Mbps operation without requiring existing four-pair CAT 3 UTP
    cables to be replaced with the newer Category 5 cables.

    Now if cables of category 3 are somehow able to transmit with data
    rates of over 100 Mb/s, then wouldn't that automatically put them into
    higher category?
    I thought categories told us what the maximum transmission rate of
    twisted pair cable is? If somehow we can enable cable from CAT3 to
    transmit with transmission rates of 100Mb/s and over, then what is the
    point of putting twisted pair cables into different transmission rate
    categories ?


    thank you


  2. Re: CAT 3 UTP cables capable of 100 Mb/s

    On Jun 7, 11:15 am, kaja_love...@yahoo.com wrote:
    > hiya
    >
    > 100Base-T4 was developed to allow 10BaseT networks to be upgraded to
    > 100-Mbps operation without requiring existing four-pair CAT 3 UTP
    > cables to be replaced with the newer Category 5 cables.
    >
    > Now if cables of category 3 are somehow able to transmit with data
    > rates of over 100 Mb/s, then wouldn't that automatically put them into
    > higher category?
    > I thought categories told us what the maximum transmission rate of
    > twisted pair cable is? If somehow we can enable cable from CAT3 to
    > transmit with transmission rates of 100Mb/s and over, then what is the
    > point of putting twisted pair cables into different transmission rate
    > categories ?



    No. The categories are standards for the physical characteristics of
    the wires. These are often matched to particular communications
    standards for obvious reasons.

    Anyway, 100Base-T4 used all four pairs of a cat-3 cable to transmit
    instead of just a single pair like 100Base-TX does. Cat-3 is capable
    of about 16Mbps on a single pair, so by adding a fairly sophisticated
    encoding/modulation scheme, they were able to get 1000Mbps over four
    (using the basic encoding scheme, they'd have only gotten 16x4 or
    64Mbps). Note that this restricted them to half duplex.

    The 100Base-T4 crew was also hoping to support 100Mbps Token-Ring over
    the same infrastructure, and was originally called 100Base-VG or VG-
    AnyLAN. But 100Base-T4 is pretty much dead, and essentially all
    installations went with -TX, and put in Cat-5 instead.

    Interestingly enough, 1000Base-T goes back to the four pair scheme,
    but over four pairs of Cat-5 (and for the same reasons).


  3. Re: CAT 3 UTP cables capable of 100 Mb/s

    On Jun 7, 9:15 am, kaja_love...@yahoo.com wrote:

    > Now if cables of category 3 are somehow able to transmit with data
    > rates of over 100 Mb/s, then wouldn't that automatically put them into
    > higher category?


    No. The category describes physical characteristics of the wiring that
    limit how much bandwidth they can carry with a particular modulation
    scheme. That doesn't mean a more sophisticated modulation scheme and/
    or using more pairs won't let the same wire carry more bits per
    second.

    DS


  4. Re: CAT 3 UTP cables capable of 100 Mb/s

    thank you

    cheers


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