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Modem Accelerators?

Posted by Cliff on from the sounds-like-digital-snake-oil dept.

An Anonymous Coward asks: "I was browsing on the web and came across a reference to Coastal Web Online's claim of a modem accelerator Apparently it is a service which is supposed to make your modem 3x faster. Is this possible? I've already got a v.92 modem and I thought it already did compression. It is possible it is a proxy doing some compression on white space in HTML or something, but I don't think so, since it apparently only works with Windows 9x and Internet Exploder. For $8.00 a month ontop a the dialup access sounds kinda snake oilish. Does anybody on Slashdot use the service? Would they recommend it? This sounds remarkably similar to the old idea of 'waxing your modem'. Am I missing out on something here?"

6 of 51 comments (clear)

  1. modem compression standards. by quinto2000 · · Score: 3, Informative

    There is nothing snake oilish about these compression claims. Only a few ISPs are supporting it, but the v.42 compression standard has been out for a while. Check out this comparison to see how it differs from older compression standards. The key is that these claimed ratios are in ideal situations -- ie, when you're downloading a great deal of text, not the high-bandwidth consuming images or video streams. Those are already highly compressed, and so are unlikely to benefit from further compression. In fact, it is a fairly trivial consequence that any compression method will make some kinds of files larger, not smaller. A fatter pipe is the only solution sometimes, and that just isn't going to happen with POTS.

    --
    Ceci n'est pas un post
  2. How to modem accelerate as a webmaster by proxybyproxy · · Score: 5, Informative

    The best thing I ever did for my modem users, was to install mod_gzip, which compresses every page (be that HTML or any dynamically generated PHP page) apache sends out.

    Result? Up to 92% compression! My pages are loading so much faster than before, AND I am saving on my bandwidth bill.

    Installation is a breeze, the mod is a beauty.

    - the mod_gzip project
    - scoop article on mod_gzip
    - some stats for intune.org

    --

    Hurra for Knark!
    1. Re:How to modem accelerate as a webmaster by mcelrath · · Score: 3, Informative
      I have been using my proxy (FilterProxy) to compress web content for me, for over a year. It *does* provide a ~5x speedup for html. You need to arrange to have the proxy running on some server with a fast net connection (i.e. upstream from your modem). The amount of time it takes to compress and uncompress the page is miniscule compared to the amount of time it takes to render it. On a modern ~500MHz or better machine, I can compress any page in <0.01s, so you really don't notice the time that it takes. If you're still on a 486 though...

      -- Bob

      --
      1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
    2. Re:How to modem accelerate as a webmaster by Tower · · Score: 5, Informative

      If the pages are static content, A) can be relieved with caching of the gzipped pages. If you are generating dynamic content (via DB lookups, etc), you'll have more of a hit, but relative to the the lookup time, the gzipping is fairly quick.

      B) you may be stuck with, but on a P100/64MB playing 192kb MP3s while surfing to a fairly involved site (say 500kB/page) the time saved over the link will more than make up for the decompression (yes, I've tried this myself). There was a large discussion on this quite some time ago (probably close to a year), and if the proc isn't pegged on the server, the client still saves time...

      Quick numbers for an actual page (366858 bytes):
      http://slashdot.org/article.pl?sid=02/03/ 04/204622 6&mode=nested
      Raw page transfer: 366858 Bytes /(5kB/s) = ~71.65s

      Gzip time: .3us on a 375Mhz PPC RS/6k with .7 load
      Transfer time: 66240 Bytes / (5kB/s) = ~12.94s
      So, unless the client will spend more than a minute to decompress this file, you will be saving time... decompressing a few .gif/.png/.jpgs for a page will be just as costly...

      --
      "It's tough to be bilingual when you get hit in the head."
    3. Re:How to modem accelerate as a webmaster by MaufTarkie · · Score: 3, Informative

      I was using it, too, until I discovered it was causing some caching problems on the clients; that is, I had it in front of a webmail program. The user could log out, go back a page or two from the button bar, hit reload, and be relogged in. Since this happens, and we have a lot of kiosks... well, you get the picture. Removing mod_gzip fixed this problem.

      Now don't get me wrong -- I love mod_gzip. I have it installed on my other webservers. Just beware that it's not the holy grail yet.

      --
      Without you I'm one step closer to happiness without violence.
  3. Sounds like.... by perlyking · · Score: 3, Informative

    it might work a bit like this open source software.

    Recompress jpegs with higher compression, remove banner ads. Gzip the remaining page and hey presto faster download, though of course that doesnt need any client side software apart from a browser that will accept gzip compression (most do).
    I guess these guys are using some proprietary or obscured format for their compression, to help them cash in.

    Not much use to those on fast connections but for a modem user the time taken to encode/decode may be faster than downloading the normal pages.

    --
    no sig.