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Sporadic Loss of Internet Connectiity for No Apparent Reason.

By cds333
Dec 12, 2007
  1. Hey Everybody,

    Hoping someone can help with a LAN problem- It happens sporadically, but always a little while after I turn my computer on (never less than a half hour, though) ; for some reason, my LAN connectivity simply dies- I can't access the internet, but for some reason, my GoogleTalk still has connectivity.

    The other computer connected to my router still works, however. It is only the first computer that gets this problem. (The second computer never has connectivity problems, BTW.)

    The problem can always be rectified by simply logging off and back on.

    Some info:

    Both comps have a static IP, as does my router.
    I am running winXP SP2 with no updates installed, and Zone Alarm firewall.
    The LAN is Marvell Yukon, with the latest driver installed.
    I have no ports forwarded to the computer in question.

    This problem seems to occur when I leave it unattended for a while. It used to fix itself sometimes but not lately (not much help, I know).

    Killing and/or restarting active processes seems to have no effect, and since this problem only occurs randomly, starting with certain processes disabled is not a practical option.

    This problem has transcended a recent OS reinstall, and multiple virus/spyware scans, so I doubt it is from a Trojan or spyware. (Incidentally, it is my second computer that I use for downloads and potentially infected applications, which is the one with no connectivity issues)

    The computer in question is an Asus A8N-SLI / AMD Processor / nVidia GPU / Corsair RAM; and since I built it myself it has a few little unexplainable quirks (such as this connectivity issue).

    As this is a pretty specific problem, I am hoping someone has had experience with this exact issue, although general help is certainly welcome.

    TIA for any assistance.

    -cds333
     
  2. AlbertLionheart

    AlbertLionheart TechSpot Chancellor Posts: 2,026

    By a process of elimination the problem seems to start with your network interface card (NIC) - update the drivers and check that it does not have some sort of built in power saving - many on board NICs can be shut down by the power saving services.
     
  3. cds333

    cds333 TS Rookie Topic Starter

    I have the latest driver installed, and as for the power saver...

    I should have been more clear in my initial post - the LAN still works, it is just the connection past my router that disables. I cannot access the main router or the internet.

    One thing that may be helpful - my first computer (the one which looses internet connectivity) has an always-active browser window which shows streaming video coming from my second computer (which includes a web server which streams the aforementioned video). Even when my internet connection is idle for a while, there is a constant stream of data coming through my router from comp2.

    When comp1 looses connectivity, the video stream from comp2 is still active; and... my GoogleTalk can still connect to the internet.

    It seems that stuff on ports other than HTTP (port 80) still work, however other than GoogleTalk, I can't recall what else works (since I can't get this connectivity-loss to happen at will)

    Is it possible that (after I have been idle on port80 for a while) the NIC 'thinks' that the datastream coming from comp2 is it's only responsibility, and therefore shuts down the HTTP capability??? (For lack of a more technical description).

    IDK, that's all I can think of; this reminds me of a problem I used to have when I was downloading a lot. Sometimes, when I was idle for a while on HTTP, but there was alot of data going through the ports that BitTorrent uses, I would loose HTTP capability, (ie. could not access the internet) but could continue receiving/sending data through my BitTorrent client indefinitely. It was almost like the NIC shut down a seemingly unnecessary port, so it could concentrate on it's most pertinent tasks and ports.

    Let me know if that makes any sense and/or there is an existing networking/hardware precedent to which my example can be attributed.

    Thanks again for the assistance.
     
  4. raybay

    raybay TS Evangelist Posts: 7,241   +9

    I would suspect my internet provider. We are finding pauses in accounts when idle. Call them and ask if they have any automated systems or packeting going on. The good providers will actually watch for problems in your neighborhood.

    We now see these problems in a number of communities... they happen mostly at high use times, and again at very low use times such as 10:30 am and 2:30 pm. We think they are doing maintenance during those times. We do know that the problem occurs by neighborhoods.
     
  5. cds333

    cds333 TS Rookie Topic Starter

    That was my initial thought too, until I realized that whenever this happened, I could still connect to the internet via my other computer (which is connected to the same router).

    Thanks for the tip though - I wouldn't put it past my ISP to try that; they used to cap my bandwidth while they claimed they had no bandwidth caps whatsoever. After I downloaded like 5 GB in a day, my max download speed would go to practically nothing, just enough to load web pages but nothing more.
     
  6. jobeard

    jobeard TS Ambassador Posts: 9,311   +617

    sounds like the ISP release/renewal cycle is failing.

    update the firmware on your router -- the symptom and this fix is often required by the Internet community.
     
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