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PCMCIA-based Network Diagnostic Tool?

Posted by Cliff on from the interesting-hardware-ideas dept.

bluelip asks: "Do any cards PCMCIA cards exist that will function as a network diagnostic/certification tool? Our Lancat and Microtest/Compas devices are aging and need to be replaced. It would be ideal to have a card we could plug into our laptop or Zaurus to use as a replacement for our bulky devices. I have seen this, but it doesn't contain all of the functionality we need. I would like the card to be able to determine hardware facts such as line length, what type of device is on the remote end (workstation or switch), next, crossed wires, etc. Another benefit would be if it functions like a normal NIC so we can use the same card for arpwatch, ethereal, and other tools. Does such a beast exist?"

7 of 25 comments (clear)

  1. forgot to mention by bluelip · · Score: 1, Informative

    I forgot to mention that our laptops primarily run GNU/Linux.

    --

    Yep, I never spell check.
    More incorrect spellings can be found he
  2. Found it, what do I get? by benjamindees · · Score: 5, Informative
    Look no further than Fluke Multimeters. These things rock, although they cost an arm and a leg. From the website:


    When connected to a copper media network, the OptiView Analyzer will automatically perform a cable test and provide you with the cable length into any attached device, including a live switch or hub port. Select the Twisted-Pair Detail Screen and see:

    * Cable Wire Pair
    * Impedance
    * Length to End
    * Length to Reflection
    * Status
    * Anomalies (shorts, opens and split pairs)
    * Receive Pair
    * Transmit Pair
    * Receive Voltage
    * Polarity

    --
    "I assumed blithely that there were no elves out there in the darkness"
  3. Nope by FreeLinux · · Score: 5, Informative

    The tools that you describe as being past their prime are Time Domain Reflectometers(TDR). They measure the difference in time between when a signal is sent and when the signal returns after being reflected by the cut end or a kink in the wire. They are then able to calculate the length of a cable or the location of a break and so forth. They are extremely sensitive (though we bang them around quite a bit, don't we?) and highly specialized. This means that they cost a fair bit of money.

    NIC cards are simply radio tranceivers that you plug into the wire. They aren't terribly sensitive and are usually cheap. They are designed and built to perform baseband signaling and little else.

    NICs in general, are incapable of performing the functions that TDRs perform. While such a beast could be built, the cost would be astonishingly high, especially in a PCMCIA form factor.

    There are very few companies that would build such a device, with Fluke being regarded as the best. But, presently none of them manufacture one. The fact that such a card would only be used in a very small niche market and would cost an arm, a leg and a first born means that they are highly unlikely to build one, any time soon.

    I'm afraid that your search will be futile. I'd recommend budgeting for a Fluke LANMeter. You'll ever be sorry for buying the best.

  4. PCMCIA TDR by obtuse · · Score: 3, Informative

    PCMCIA TDR is here, but it's an AOL members page, not a real commercial site, so I'm suspicious that it's vapor. I'd expect a company that tooled up for a PCMCIA TDR to be able to afford a real site. It's also not a NIC.

    It's the second link on googling
    pcmcia time domain reflectometer -optical

    http://members.aol.com/tdrcard/home.html

    --
    Assembly is the reverse of disassembly.
    1. Re:PCMCIA TDR by Guy+Harris · · Score: 3, Informative
      PCMCIA TDR is here, but it's an AOL members page, not a real commercial site,

      ...but it does link to a commercial site that has information on that PC Card TDR.

      However, the software is DOS/Windows-only, so it won't work on the Linux laptops he/she mentioned in a followup posting (without software work of some sort, unless the software requires nothing in the way of special kernel-mode driver code and can run under a DOS emulator or Wine).

      The devices being replaced might also do more than just TDR, in which case that card might not do all the original poster needs.

  5. TDRs are not really a problem.... by hughk · · Score: 3, Informative
    All a TDR does is to generate a pulse and show the reflection. Suitable pulse generators can be made for a matter of a few dollars. A scope costs money, but this can be replaced by a good A/D and a computer.

    There are already devices out there that replace a scope, that you can connect to a laptop. Too big to be PCMCIA, but not that large and can connect in via USB/Serial/Parallel interfaces.

    I would guess that a PCMCIA sized device combining a pulse generator with a fast A/D would be difficult, but something a little larger would be possible.

    A Fluke LANmeter is nice but not at all cheap. It is also well built like their multimeters and can take a certain amount of abuse.

    --
    See my journal, I write things there
  6. Unfortunately, no by modus · · Score: 3, Informative
    PCMCIA TDR devices do exist, as described above, but they are esoteric and expensive.

    On the plus side, the Fluke MicroScanner Pro does everything you describe and is under $400, based on a quick pricegrabber query.

    It's much smaller than the tools you currently have and built by one of the best in the business.