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Fast TCP To Increase Speed Of File Transfers?

Posted by simoniker on from the turbocharge-your-interweb dept.

Wrighter writes "There's a new story at Yahoo about a new version of TCP called Fast TCP that might help increase the speed of file transfers. Sounds like it basically estimates the maximum efficient speed of your network, and then goes for it, dumping a lot of time-consuming error checking." There's also an article at the New Scientist with some additional information.

4 of 401 comments (clear)

  1. zmodem??? by case_igl · · Score: 5, Interesting

    I remember back in my BBS days what a big deal zmodem was when it started getting used all over the place. As I recall, it changed the block size that you would receive dynamically based on line quality.

    So when you sent a block of 2k and got no errors, the frame size increased to 4k...8k... etc etc... Sounds like a similar approach.

    Case

    P.S. That was a long time ago in a FidoNet far far away, so my terms may be off.

  2. Article is inaccurate and misleading by zeds · · Score: 5, Interesting
    The New scientist writer clearly has no understanding of how TCP/IP or the Internet work in general and how Caltech's FAST could improve data transfer efficiency. His sensationalist claims that this could enable downloading a dvd in seconds are so much ignorant crap. 6000x faster than broadband? That has more to do with the fact they used an INCREDIBLY FAT PIPE (a 10gigabit connection), probably in a laboratory setting, than any of FAST's optimizations. It's true TCP/IP's efficiency maxes out at a certain rate, but that doesn't really matter in the real world, because nobody is actually downloading movies from dedicated 10gigabit links to the backbone. Not to mention that you won't see anyone serving anything at these speeds for the next decade or so. I wonder what this suggests about the accuracy of articles on subjects I know nothing about. It's an academic curiosity folks.

    See caltech's press release on FAST for an article that actually makes sense.

    Also, could someone please explain to me why boringly predictable stereotypical slashdot feedback is being modded up?

    "Whoa! Faster pr0n!"

    "Imagine a beowolf cluster of these!"

    -Insert completely unrelated Microsoft bashing post here-

    -Insert completely unrelated technobabble from some geek posting out of their ass (without reading the article first)-

    News for nerds. Stuff that matters. Discussion that doesn't.

  3. Eliminating 'burstiness' of TCP/IP by Daniel_ · · Score: 5, Interesting
    If I'm reading the article right, they're using the same technique that a doctoral candidate did his Phd thesis on at OSU about 3 years ago.

    TCP is extremely bursty - it pumps all the packets it can as fast as it can over the network as soon as the window opens. Then it waits for replies to all the packets. What typically happens is the burst from the NIC overloads the local router causing numerous dropped packets. This gives the imporession to the sending machine that the network is overloaded and results in a ~90% reduction in bandwidth utilization.

    The change is to include a timer that allows the NIC to space the initial burst over the entire window. This prevents the overloading at the router and permits the NIC to reach near its theoretical maximum bandwidth.

    In tests involving one router, the results were an order of magnitude increase in bandwith utilization. I'd be interested in seeing their test setup to see how they got such dramatic improvements. Normally TCP/IP is not that ineffecient - even with its extreme burstiness.

    --
    The number you have dialed is imaginary, please rotate your phone 90 degrees and try again.
  4. Re:6000 TIMES !!! by elem · · Score: 5, Interesting

    Actually if you read the New Scientist artictle you can see that that's a lie. What they actually did was bundle 10 FastTcp connetions (one must assume on fast lines) togeather and, fairly unsuprisingly, got speeds 6,000 times fast than a broadband connection... wow... 10 high speed lines are faster than broadband??

    This would be more interesting had they actually tested it on a standard 512kbs connection and seen if there was a speed increase. IMO it most likely would not make a huge a difference anyway since alot of the slowdown on a consumer broadband connecting is the connection buffers at your ISP. For a better explanation read the Traffic Shaping HOWTO.