Routed by my slow router

July 12, 2007 4:24 PM

Why is my brand-new router massively slowing my Internet connection, even when everything's connected with cables?

There have been several slow router questions on Ask MeFi, but I couldn't find one that really matched my situation. We recently became a two-laptop family. Our first computer is a Thinkpad T42, which we had been using connected directly to the jack in the wall via Ethernet cable. Nice fast connection. We now have a MacBook Pro, so I bought a router (Belkin Wireless G) and connected that to the wall. The Mac works fine, but the Thinkpad now loads pages very slowly. What confuses me is that this is the case whether I run the Thinkpad on the wireless, or run a short Ethernet cable directly from computer to router. Why should the latter be any different from connecting the Thinkpad directly to the jack?

Some possibly relevant data based on my reading:

* Some posters mentioned that encryption from the router might slow things down. I _tried_ to encrypt the router when I set it up, but I think I failed; at least, I was never prompted for a password when I connected to the wireless on my Mac.

* The Thinkpad can run Linux or Windows XP, and the slowdown happens either way.

* I guess one possibility is that the short cable connecting Thinkpad to router is faulty; I only have one, so I haven't been able to check. Could a bad cable slow down the network connection without cutting it off entirely? It still works fine, just much more slowly.

Thanks for all help!

posted by escabeche to computers & internet (7 answers total)

Define "slow"? Does it take ages to find the page but, once the page start loading, loads fine? Or is the whole process of page loading slow?

If the latter, a quick guess would be the MTU setting of the laptop. Drop it to 1492 or less (go down in steps of 8) and see how it goes.

A-ha! There seems to be a known problem with that combination of router & laptop. Though that link talks particularly about bad wireless performance - have you tried actually disabling the wireless adaptor on the laptop while connecting via the ethernet cable, just to be sure?

(FWIW, I found that second link by Googling +"belkin" +"wireless G" +"slow". You might find more ideas there.)
posted by Pinback at 7:27 PM on July 12, 2007

(Sorry, I got that second link wrong, but it's still informative. Still, many Belkin products seem to be real dogs, and that particular problem crops up surprisingly often in association with T42's.

Myself, I'd take it back and cough up the $$$ for a cheap switch/hub for wired ethernet and an AirPort Express for wireless. I'm thoroughly impressed by how easy the AirPorts are to set up compared to anything else out there.)
posted by Pinback at 7:41 PM on July 12, 2007

So, now that you put the mac on the network the thinkpad is slowing down? Have you tried shutting off the mac to see if the speed resumes? I have a mac mini, and it has a setting called 'Interference Robustness'. One of the things that this setting does is decrease packet size, which decreases throughput. This might be affecting the mac positively and the thinkpad negatively. (I'm speculating here.)

I found the info on 'Interference Robustness' on this page.
posted by philomathoholic at 11:05 PM on July 12, 2007

you say connected to the wall - are we talking DSL or IFITL? do you have a t1 or t3 line in our house? router placement is important. is every jack in your home is broadband capable.
posted by Davaal at 11:43 PM on July 12, 2007

If it is a problem under both windows and linux it would be a fluke to be an MTU issue, so probably something else.
Can you please clarify whether it always the wireless link that is slow, i.e. is the mac slow on wireless, and is the PC still slow when plugged in directly and vice versa?
posted by bystander at 4:58 AM on July 13, 2007

Thanks, you guys are giving me some good stuff to try! Some answers to questions above:

On Mac, wireless and wired are both fast.

On Thinkpad, wireless is slow, wired via the router is slow, wired directly to the wall is fast.

Re our wall: I am using ResNet at the University of Wisconsin, and from their documentation, it looks like we have DSL; I wasn't able to figure out whether we had T1 or T3.

Pinback's link is quite interesting, though the person there seemed to say that their Thinkpad was slow on the wireless but fast when attached by a cable to the router, unlike my experience. I'll try some of the suggestions here. Pinback, does "actually disabling the wireless adapter on the laptop" just mean setting my network preferences to say I'm connecting via the ethernet port, don't look for wireless? I've done that. Or are you talking something more serious like physically removing the card from the laptop?
posted by escabeche at 8:15 AM on July 13, 2007

As a sumup, in case anyone else has a similar question, I bought a Linksys Wireless G router and now everything works fine.
posted by escabeche at 8:43 PM on September 3, 2007