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Maximum Modem Speed

  1. Apr 18, 2005 #1

    How do i test the maximum speed of my Modem?
    Note: i dont mean the internet connection speed, purely how fast my modem can transfer the data.

  2. jcsd
  3. Apr 19, 2005 #2
    it depends on what type of connection you are using but I think www.2wire.com has some bandwidth tests that are free and fast. Go to thier site and click speed meter at the top.
  4. Apr 28, 2005 #3
  5. May 9, 2005 #4


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    It would hard to isolate the modem itself for such a test. The phone line, for example, has a lot to do with the maximum transfer rate of the entire system.

    Even a theoretical number would be hard to get, because modern modems do quite a bit of data compression, so the transfer rate depends also on the type of data you're feeding it.

    - Warren
  6. May 9, 2005 #5


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    Staff: Mentor

    If you aren't wanting to test the connection speed, are you asking what speed your modem is designed to offer? (56k is the maximum for dial up modems) or are you asking about trying to determine how well your particular modem is performing? I am not aware of anything on line that tests for that. There are products that you can purchase for this type of analysis however.

    Here is one company that sells a product that sounds like it does what you want. I have no idea how good the product is and I am not endorsing it. I would shop around.


    "ModemTest is an easy to use Windows based application that allows users to test their dial up modem. ModemTest performs low level testing that is independent of your Internet Service Provider (ISP) and the TCP/IP settings on the computer. It allows the modem to be tested in addition to the phone line the modem is connected to."
  7. May 9, 2005 #6
    Hard to say honestly.

    For instance, my friend used to have a 56k modem...usually transferred data at around 3 kb/s or so.

    One strange morning, however, the network must have been used by no one but him or something, but he could connect/transfer at 128 kb/s, on a modem. Very odd indeed...only ever happened once though.
  8. Jun 12, 2005 #7
    That is unlikely through a modem, even cable modem hardly get that rate of the internet unless the server you connected to is very fast and not busy. It's probably bits rate you are seeing not bytes.
  9. Jun 12, 2005 #8
    Modems advertised at 56k speeds are actually advertised in bits, 56000 bits ~ 7 kb/s actaul transfer speed. FCC Law limits the maximum speed to 53,000bps, which is the absolute maximum you can obtain for dialup. The highest I've gotten is 51,666bps.

    The transfer speeds you see on your download windows are almost always in kilobytes per second. a 3kb transfer rate is equivalent to 3000 * 8 = 24000kbits, thus your connection is running at a little less than half its capacity.

    The experiment as you've labeled it doesn't really seem possible. Chroot and evo's advice pretty much explain why.
  10. Jun 16, 2005 #9
    the reason for the maximum speed on the modems is due to the size of the phone lines physically, you can only push so many electrons down them at one time before they will melt the lines from the friction. another thing that determines your line speed will be the distance that you are from the main telephone switching house, i think it was every 5 or 10 miles the line speed is reduced by 1/2. so a 56k modem about 10 miles away lets say would actually be running at 28.8 even if it said u were connected at 56k.
  11. Jun 16, 2005 #10
    hmmm... So why do I have 8M dsl over a normal pstn analougue line if this is correct, with is exactly the same telephone line as a dial up works through...

    FYI in telecoms we say b = bit and B = Byte
  12. Jun 17, 2005 #11
    hello all

    well I remember at a period of 6 months when i first got my computer it was running just above 100 kbps then my computer crashed lost everything now it runs 28.4kbps when i called the technical support of my server they told me that it can happen in some cases with particular drivers for modems, when I tried to look for the driver I realised that the computer company i bought my computer from did not give it to me when i bought it, I have to admit i really miss my fast internet, does anybody have any suggestions on how to make my internet faster than what it is? or does anybody know of any good drivers? please help thanxs

  13. Jun 17, 2005 #12
    Steven, do u know what is ur modem brand and model no?
    If Yes, then try to search it in google with ur brand and model no as the search term.
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