Intermittent connectivity issue

August 31, 2009 9:23 PM

How do I know if it is my router that is causing me connection headaches?

I have a habit of browsing in Firefox with many open tabs at any time. Lately - and with increasing frequency - when I open the browser, many of the tabs will not load. Constantly hitting refresh will, after reporting eventually load them. Then, intermittently, any particular tab will be unable to follow a link - I get a 404 not found message. Reloading *repeatedly* will, again, eventually fetch the page, but the dead moments seem to be getting longer and longer. (No tabs will actually open links at these times - any link gets a 404 message.)

A few months ago, I made the leap to a wireless home network and bought my first router. The router I am using is the cheapest one I could find, a Belkin MyEssentials Wireless G Router. The desktop computer that is having the issues is actually attached by wire. My netbook and Palm Pilot connect wirelessly without trouble, and I haven't had the same problem with them - but I browse MUCH less often on either of those. I never had this problem before I got the router - but I also didn't have it for four or five months AFTER I got it too.

Should I go ahead and try a better router? I've never understood the differences in function between cheap routers and more expensive models, and the price range is considerable.

Or should my suspicions focus more on my DSL modem? Or my ISP itself? Or a virus? Or...

Sigh. I want this problem to go away. I'm not real resistant to frustration, and my cat is getting tired of being hollered at for no good reason.

posted by John Smallberries to computers & internet (11 comments total)

I had almost the exact same problem a coujple of months back, while i was home recuperating. I was using the el cheapo 39 dollar Netgear router. A friend loaned me a newer wireless-N router, about 100 dollars at worst buy. ~cleared it right up.
posted by pjern at 9:41 PM on August 31

If you're getting a 404 error (assuming you're not behind a malfunctioning proxy server), then the router should not be the problem since the destination server ought to be the one giving you the 404 error. A bad router might cause slowness, but if you actually get a 404, it's not the problem. Instead, I'd expect a "server not found" message or similar.
posted by tomwheeler at 9:54 PM on August 31

Have you checked to see if you are running the latest firmware for your router? You'll have to find your Belkin model number from the sticker on your router, and then download any applicable firmware update. Login to your router's administrative interface over a wired (not wireless) connection, and follow instructions for applying the update file to your router, if applicable. Don't update your firmware unless the update file is a higher version number than what your is reporting it is running. But if your router has older firmware, updating it may fix connection problems.
posted by paulsc at 11:12 PM on August 31

Another thought, since you are getting 404 errors from the servers, is that you may be having some HTTP compression issues with Firefox, as explained in this Fogbugz note. HTTP compression is a scheme between Web servers and browsers to save a little transmission bandwidth, by compressing the text of HTTP page headers, and relevant text and markup in Web pages, with a compression utility kind of like .zip. It uses a little server CPU time and some client CPU time on your machine to do the compression/decompression process, but speeds up page transfer, especially on slow dialup links. At the start of every page transfer, the client asks the server if it can send a compressed version of the page, and if the server has it available, or can create it on the fly, the page that is sent is compressed, and a header string is appended to indicated that this is a compressed page, and that the browser should decompress it before rendering it for display. Browsers read that header (Firefox), or examine the sent file (IE 7 & 8) and decompress it on your machine before displaying it to you. But if the server screws up the encoding in certain ways, your browser is going to have trouble decoding information correctly. You can get "busted" links, and dead page requests sent back to the server from your browser, leading to 404 error "Page Not Found" messages from the server.

So, you might try turning off HTTP compression in Firefox, by editing your network.http.accept-encoding preference in Firefox. Or, leave your Firefox preferences set for defaults (use compression) and add/use an extension like HTTPFox to monitor connections to pages which have problems loading. Nothing much you can do if a server is munging the HTTP compression process, except report it to the server administrator, and quit asking for the compressed version pages until the server is fixed.
posted by paulsc at 12:47 AM on September 1

Ok... I am a schmuck. I AM getting the "server not found" message, which my apparently oxygen deficient brain insisted on describing as a 404 message in my initial post.

I also forgot to describe a second, possibly seperate symptom/issue - when pages do load, they frequently seem to load incorrectly, showing up as bare, badly formatted text, like all the CSS info is missing. Images also seem reluctant to load. Repeated refreshes eventually get the page loaded right, but damn it is annoying!
posted by John Smallberries at 2:21 AM on September 1

"Server not found" could be DNS errors. The Domain Name Service is responsible for translating the URL strings you type into your browser, or that your browser gets as links from Web pages, to the Internet Protocol (IP) numerical address of the server hosting that URL. Sometimes, you can get better DNS service from a third party like OpenDNS, than you can from your ISP's DNS machines. You should be able to set your preferred DNS server numbers in your router, which will then hand them out to all your networked client machines, via DHCP address assignments. See your router documentation for how to do this.

The borked pages and slow load times issue could be a lot of things, from dropped packets, to HTTP compression issues. You might want to visit the Tools page of DSLreports and run some of their tests to analyze your connection. If you're getting lots of dropped packets, your TCP/IP stack is being forced to request re-sends from the servers, slowing down your overall connection, in an effort to get missing packets. This also slows down or stops the rendering engine in your browser. Post back here with the results of any connection tests that appear wonky, and you may get more specific recommendations.

It may also help you, at least temporarily, to clear your browser cache, and increase its size on disk. Your browser will preferentially use locally stored images and other parts of Web pages when rendering them, rather than download fresh copies, if it finds that the copies it has are current with what it could get again, from the servers. So, it pays to give your browser plenty of space to cache these elements - 100 to 250 MB of local cache is not unheard of for modern sizes of hard disks.
posted by paulsc at 2:55 AM on September 1

This could be approximately 1000 different things.

You can test if it's DNS by changing your server to 4.2.2.1. It's a public recursive resolver that people have been using for tests/backup servers for a long time. I wouldn't use it permanently, but you can see if your problem goes away when using it. Right now you are probably using one of your ISP's upstream resolvers, supplied by DHCP. If it turns out this is the issue, you could try complaining to your ISP, or see if you can manually pick a different resolver. They usually have a few in your netblock to choose from.

It sorta sounds to me, though, like your problem only manifests when you try to establish many connections at once. This could easily be your ISP or the router choking. The only way to eliminate the possibility that it's your router is to hook up a different one, sadly. Either that or plug your modem directly into a computer to bypass the router. Depending on the hardware involved, you may need a crossover cable to do this, and reboot the modem so that it gets a new lease.
posted by cj_ at 3:22 AM on September 1

The best way of telling whether it's your router that's causing the problems is to connect directly to your modem and see if the issue goes away.

Clearly, this isn't how you want to run for any reasonable length of time, but a few minutes to check DNS, etc. won't hurt.
posted by valkyryn at 4:21 AM on September 1 [1 favorite has favorites]

As valkyryn says, remove the router from the loop, connect directly to the "modem", and test the crap out of it. Compare your laptop and desktop in this way, too.

Also check for cable problems by swapping cables. A nasty crimp or fold in an ethernet cable, maybe as it was dragged over a nail, can reduce its effective throughput to near-nothing.

All troubleshooting is just eliminating variables.
posted by rokusan at 5:56 AM on September 1

I've been having similar problems on FireFox 3.5 on Windows 7. I haven't fixed it yet. If I go back to an earlier FireFox it goes away though.

Here's a forum thread talking about my issue: http://forums.mozillazine.org/viewtopic.php?f=9&t=1341345
posted by Liver at 6:23 AM on September 1

Liver: "I've been having similar problems on FireFox 3.5 on Windows 7. I haven't fixed it yet. If I go back to an earlier FireFox it goes away though.

Here's a forum thread talking about my issue: http://forums.mozillazine.org/viewtopic.php?f=9&t=1341345"

Wow - some of the complaints on that forum sound awfully familiar. It never occured to me that Firefox could be the culprit. Now I got another thing to eliminate.

Heh. The fact is that what I was really hoping for was someone to tell me that if I just looked under the hood, there would be a big red switch marked "screwed up/fixed" that needed to be set from the former to the latter. Instead I get all this useful advice that now requires an effort from me. Thanks a pant-load.

Joking aside, seriously, my thanks to you all. Now I have a plan of attack to end this irksome issue.
posted by John Smallberries at 8:52 AM on September 1