More Comcast weirdness
In the latest twist in my Comcast saga, I have another techie scheduled to come over tomorrow afternoon, due to the continuing intermittent speed and connectivity problems I've been having. The latest odd behavior has been a couple of instances where my connection has slowed to an inconsistent crawl, and when I've done a speed test, I've gotten a perfectly reasonable downstream speed but no upstream reading, like so:
Anyone have a clue what might cause that? I'm stumped. I just know that, when it happens, it seems to produce extremely erratic behavior: one minute, stuff is loading fine; the next, it's not loading at all; the next, it's crawling; then it's suddenly fine again. Very frustrating.
How old is your modem and router?
If wireless, what protocol g? n?
Posted by: Nadine | Apr 11, 2008 10:26:55 PM
Router is the Apple AirPort Express, wireless g. I think it's less than a year old, because I got it replaced for free at the Apple Store fairly recently, due to a problem with the audio out port thingy.
Cable modem is a D-Link DCM-202. We bought it in May 2006. We used it form May-August '06 in Arizona, then packed it away (because our apartment in South Bend had ethernet jacks in the walls) and didn't use it again until we got here to Knoxville in May '07. We've been using it steadily since then.
Posted by: Brendan Loy | Apr 11, 2008 10:34:19 PM
How far from your computer is the Airport?
Posted by: Nadine | Apr 11, 2008 10:35:28 PM
Um... about 12 feet, give or take.
Posted by: Brendan Loy | Apr 11, 2008 10:37:58 PM
For a first pass test, hard wire your Mac to your cable modem and see what your download and upload speeds are.
Posted by: Nadine | Apr 11, 2008 10:42:23 PM
And yes, I had about the same distance from Airport to computer. AND the same problem.
Posted by: Nadine | Apr 11, 2008 10:43:56 PM
The problem with that is, it's an intermittent problem, and is often temporarily resolved by resetting the modem anyway -- and resetting the modem is necessary to switch from the router to a direct line to the computer. So when I've tried this, I get good readings, but that doesn't actually tell me anything. I continue to get good readings when I re-reset the modem and plug it back into the router... so it's not necessarily the direct line that's "fixing" the problem, but rather the simple act of unplugging the modem and plugging it back in again. Which doesn't mean it won't happen again in 5 minutes or 5 days... ugh. Intermittent technical problems suck.
Posted by: Brendan Loy | Apr 11, 2008 10:53:50 PM
All true. So don't reset the modem BUT move your computer MUCH closer to the router, like a foot. Again test for up and down speeds. You call this speed issue intermittent but it's approaching chronic.
Posted by: Nadine | Apr 11, 2008 11:05:34 PM
Okay, I'll try that the next time it happens... thanks.
When I say "intermittent," I don't mean to use that word in a way that minimizes the severity or frequency of the problem -- I just mean that the problem is unpredictable and not constant, which makes it difficult to re-create, test, troubleshoot, etc.
Posted by: Brendan Loy | Apr 11, 2008 11:18:07 PM
It may be unpredictable, in that you don't know at this point why it happens, but I will venture to guess that you probably have not had it happen during 6:00AM-6:00PM.
Noting the slow down incidents will help to reveal a pattern if there is one.
What has your website traffic been during the last forty-eight hours?
Posted by: Nadine | Apr 11, 2008 11:33:38 PM
10,084 hits today, with less than 20 minutes till midnight, thanks to all the links (Sully, TNR, NYT, Insty).
1,567 yesterday (a typical day, roughly speaking)
So... about 11,700 total in 48 hours.
Posted by: Brendan Loy | Apr 11, 2008 11:44:35 PM
http://www.webware.com/8301-1_109-9686136-2.html?tag=blog.5
Article about Comcast and usage limits.
Posted by: Nadine | Apr 12, 2008 12:29:11 AM
My website's traffic has nothing to do with my Comcast connection, though, if that's where you're going with this. My website is hosted on a combination of TypePad's servers, wherever they are, and a WestHost server in Utah. Nothing goes out over my Comcast connection except my own uploads & downloads, etc.
Posted by: Brendan Loy | Apr 12, 2008 12:41:29 AM
Thanks for the link, though. It's interesting. :)
Posted by: Brendan Loy | Apr 12, 2008 12:45:28 AM
Have you tried the signal booster option? I had the exact same problems and they went away by doing that. Also try unplugging the TV from the splitter and see if it fixes it next time you encounter the problem
Posted by: David K. | Apr 12, 2008 12:59:31 AM
Check with your neighbors and see which peer-to-peer networks they're using. Then figure out which one has several terabytes of [porn|mp3s|movies]. Snip that guy's cable. Bandwidth fixed!
Posted by: Michael | Apr 13, 2008 3:59:32 PM
cable internet doesn't suffer from the same sort of shared bandwidth issues they did in the late 90s.
how many machines are connected to your network? is the network secured? it's not uncommon for one machine to saturate upstream bandwidth, making the connection itself seem slow.
A common way to troubleshoot this would be to remove machines from the network one by one, seeing if the problem goes away when any one machine is removed.
Of course, with a wireless AP, the additional challenge is to ensure that there are no outsiders using the connection. If it's open, or using WEP (in which case it's close to open) this is a possible scenario. Take a look at whatever administrative tools come with the AP to see if it will tell you how many clients are connected.
Posted by: Jim | Apr 13, 2008 6:37:01 PM