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Cable Modem Primetime Slowdown - Myth or Reality?
The Llama King asks: "SBC (SWBell, Pacbell, etc.) is whacking away at Time Warner cable in our area, running DSL ads that make fun of prime-time cable modem slowdown. And Time Warner-Houston/RoadRunner does seem to be having a problem in the past month with nasty ping times between 8 pm - midnight Central time (traces submitted to internal RoadRunner news groups show the problem appears to be a pair of routers at the gateway to one of several backbones). While this problem is recent, it begs the question - are prime-time cable slowdowns real or a myth? Can a well-configured cable modem network avoid the congestion SBC pokes fun at in their commercials, or is it inevitable? What are Slashdot users seeing?"
Ameritech is running the same types of ads here in Ohio as well. What the ads don't say clearly is that you need to live next door to the central office if you want the maximum DSL bandwidth. For me, where I live nearly 3 miles from the CO, the best they claim for me is 128Mbps either direction. All that for $50 a month.
By contrast, the cable can handle huge amounts of bandwidth down and I'm pretty much assured a minimum of 128Kbps up. But, the cable bandwidth is shared among all my neighbors. It's important to realize, though, that all my neighbors aren't sharing 1.5Mbps down and 128Kbps up. It's more like 10.5Mbps down and 512Kpbs up. Business customers can get a dedicated line that gives them the entire bandwidth. Heck, Road Runner Columbus even offers what they call a "direct connection" to the internet at up to 45Mbps symetric.
Back to this topic, have I ever experienced a slow-down during peak hours? Nope. But I now live in a subdivision that I am certain isn't abusing the cable network. When I lived near Ohio State, however, I did find at times I was limited in bandwidth and Time Warner had troubles with their DHCP server getting overloaded. The worst data rate I ever was able to receive was somewhere near 500Kbps. That's many times better than most DSL lines. And at $45 a month (new price "adjustment"), it's easily the better choice.
Long, cute, or funny Sigs are just another form of over compensation, used by geeks, nerdz, etc.
Charter Cable here in Auburn Worcester Area has "ever changing pings". For sometime now I have never been able to get anything even resembling a consistent ping time or download rate. Somedays the connection flys the next its barely faster than a 56K modem. During the whole "Code Red" thing it was just sad, the light on my linksys router, for activity was just solid didn't blink at all. I called them several times and asked them to look into the reasons why their network was in such a state. I telecomute into my compant from time to time so this period was esspecially annoying. I am still monitoring several Code Red, Nimda, and related virus'es a day knowcking on the door. I guess in the end the moral of this story, the network only as good as those who run it, and even less good if they never listen to the users of the network who try to tell them whats wrong.
Power Corrupts,Absolute Power Corrupts Absolutely, leaving one person(group)in charge is absolutely corrupt.
Well, mine stays the same most of the time and lately it's been better. Yes, during the evenings it's slower, but not that slow. My slowdown is usually caused by the DNS being a bit on the slow side. Once the address is resolved, it pops up fairly quick. That's most of it. A few times I can definitely say it was excess traffic in our neighborhood. New Years Eve was one where the network slowed to a crawl if it worked at all and this weekend, after the attacks happened, it seemed to be VERY slow and not fast until sometime Monday Morning. I get INCESSANT hits on the firewall since Code Red and Nimda. For a while, my activity light was lit solid for DAYS on end. I used to get 100-200 hits on the firewall per hour. Now, I still get too many hits and they are all coming from local IP's, but only about 10-20 an hour. I get VERY few hits on the firewall from IP's outside of road runner. It's all local traffic. Some of it seems to be pings from the provider as well. I think most of the hits seem to be Road Runner scanning the network looking for unpatched IIS boxes or unauthorized servers (it is in the agreement(no servers)folks and they have every right to do it no matter how stupid we think it is....).
I agree with the other person about the DSL ads and the fact that you have to be practically ontop of the CO to get the high speeds. I am only 1 mile away and I couldn't even get 128 K a while ago. Now I can get it, but it's all slower then and more expensive then my cable modem. Lately, Road Runner has been REAL attentavie to outages even. I remember one time I was out for a whole day and I didn't even call techsup and I had a credit on my bill the next month. That's cool. They KNOW when these outages happen. You should not have to call and bitch to get a credit. I do know that they are starting to be more attentive to customers, although their network issue page is usually out of date. At least they are updating the equipment gradually. I used to have a legacy modem, but after one REAL long outage, they gave me a new DOCSIS modem. Plus I think that some cable providers are loosening the IP restricitons and not hassling people who want to share their connection with other machines. Cable Modems are getting better. They have to or they are going to really loose it when the local phone companies get a clue about DSL and reduce price and make it competitive and make it so you don't have to live over the CO to get a high speed connection.
Gorkman
With a cable modem, the only difference is that the very first hop might also be oversubscribed.
A cable has a lot of bandwidth. That bandwidth is divided up into channels (on an NTSC analog system, channels are all 6Mhz wide, your channels may vary). Each internet cable box is assigned a channel (or set of channels, if channels only come in one size). Your next door neighbor's cable box might use a different channel, and thus not be in the same neighborhood.
Logically, a cable system is a tree, or set of trees, with the root of each tree at the cable company office, and the customers are the leaves. The thicker branches may run on fiber, they support more channels, and therefore more neighborhoods.
A wee tiny cable company may have a single T1 (1.5Mbps) line connecting to the greater internet, a large company might have several OC48 (2.5Gbps). The same is true for DSL providers.
ISP's either charge premium rates or they oversubscribe the service, or both. I don't see a primetime slowdown on my $180/month, 384K DSL line.