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Cable Beats DSL For Average Speed
zymano writes "CNET article here says cable modems are 50 percent faster on average than DSL connections which I think most have suspected . There are some connection rates that i found interesting like Cablevision reportedly having the fastest connections, averaging 800kbps, or 13kbps above the industry average. Mentions other cable company speeds. TimeWarner cable was not tested."
Yes, cable's more vulnerable to that - although with DSL, you're still sharing the backhaul pipe from the DSLAM to the ISP, and of course all the ISP's customers are sharing the ISP's pipe(s) to the rest of the Net. The tradeoff is that cable has much more bandwidth to share.
In theory, with some clever traffic shaping, you could give "interactive" users the full bandwidth of the pipe (in short burts) - so when you view a webpage, it arrives at many megabits/sec. Then after, say, the first megabyte (a fraction of a second at full bandwidth for a cable segment), start throttling back to the "bulk download" rate. That could give insanely fast interactive performance (even really bloated webpages would appear in a flash, if the remote server can manage it) without taking the financial hit of Kazaa users eating a couple of Mbps 24x7.
P2P is, as you say, a huge problem on cable segments (and on DSL: it's still shared once you reach the exchange); one user running Kazaa can easily eat the bandwidth of a few dozen "normal" users. Either the ISP has to buy a load more bandwidth to cope (and a massive price hike to cover it), or do something to stop them: traffic shaping, ban it (and enforce that ban), or impose traffic quotas.
If you're running a server and need a static IP address, or multiple IP addresses, you need DSL (or ISDN, or a T-1, or *gasp* dedicated dialup -- don't ask.)
On the other hand, if what you want is the highest possible download speed for the lowest price (Kb per sec per dollar per month), cable is the way to go.
I know a few server-at-home geeks who actually have both DSL and cable: DSL for the static IPs for their servers, and cable for surfing. I'm thinking about going this way myself. The really interesting project will be setting up a dual-homed box to do intelligent routing of traffic across the DSL with the static IP and the (presumably faster) cable modem with the dynamic IP.
-Mark
until everyone up your street gets cable because of this report and yer speed drops.... ;)
Cable modem scales a lot better. They can have one hub serving an wide area, and if the speed drops then the area can be installed by installing a 2nd hub and splitting the area into two. With DSL, every line has to go all the way into a (physically restricted in size) exchange.
In Surrey, I had both cable modem and DSL. Cable modem was both faster and had better ping time for gaming.
Phillip.
Property for sale in Nice, France
From RoadRunner (Time Warner) Midsouth, to one of the Ultima Online game servers I play:Having read the UO message boards for a long time, it seems like DSL users tend to get slightly better pings (averaging 15-20ms, I've seen some on speakeasy who claim pings of 5ms). However, I'm perfectly able to compete with my latency. I'd rather have a 40ms ping average to game, and also be able to download at 250KB/sec.
It really depends on what you use your connection for the most, and how you prioritize those uses. Someone who is generally a casual uploader/downloader but does a ton of gaming might be better off with DSL, for the apparent latency boost. Someone like me, who enjoys gaming but spends a lot of time uploading and downloading as a coder/sysadmin is better off with cable and its apparent throughput boost.
For me, it boils down to the work side of things. I have (among others) one mysqldump that's over 900 megs, which I download 3 times a week to maintain as an offsite backup[1]. There are a number of other dumps I download for backup purposes as well, probably totalling 500+ megs in their own right. When it comes to downloading 900 megs - or especially a gig and a half - there's a noticeable difference between a 150KB/s download cap and a 250KB/s download cap. I can give up a few lag-deaths in Ultima Online now and then as a tradeoff to getting my "important" file transfers faster.
At the risk of sounding like a Time Warner apologist (I have a rather botched history with AOL, so believe me I'm no fan) I have to say that cable has always been more appealing to me than DSL. Then again, I've always been more concerned with how fast I can download
Just my two cents.
[1] Yeah, I'm probably one of those hated "power users" from the cableco's standpoint. `ipfw show` claims ~32 gigs in 24 days uptime, but until I hear any complaints, I figure I'll use the broadband I pay for.
"BSD: Free as in speech. Linux: Free as in beer. Windows 10: Free as in herpes." --Man On Pink Corner in #52607549.
The article is talking about averages, so it shouldn't be surprising that there are a few cases where DSL is faster than cable.
In my area, I think more people get a solid 1.5Mbit ADSL connection than in other areas of the country. That's as fast as cable is around here, but DSL also gives you 256k upstream while the cable companies here (Atlanta) seem to only offer 128k upstream.
There are 2 reasons for the fast DSL speeds around Atlanta:
1) Bellsouth has installed many remote terminals, so even if you're 18,000 feet away from a CO, chances are you're much closer to a RT where the DSLAM actually is, so many people get much faster speeds than they expected to get.
2) Fiber to the Curb. It's all over the place here. The technology for allowing ADSL over a fiber connection is very new (less than 6 months in deployment, via proprietary equipment from Marconi) and essentially means your DSLAM is only as far away as the fiber pedestal in your front yard. In a house with new cat-5 wiring, that is basically as close to ideal lab conditions for ADSL that you can get. In some areas BellSouth had already deployed a different technology that had fiber with integrated data support (IFITL) that was basically ethernet straight into the house, no modem required. Between 3Mb and 4Mb download speeds for the lucky few that have it. That probably was not included in this survey though since it's neither DSL nor cable.
I'd say the biggest difference between DSL and Cable is that DSL is that DSL is a switched network, even though it is still shared bandwidth at some point. Cable is a broadcast network, your cablemodem just listens for the data intended for it.
DSL also seems to have lower and more consistent ping times, better for gaming. If you have a ton of cable modems on a node, the ping times should increase (I don't know by how much) because only one cablemodem on a node can transmit at a time. For uploads, the cablemodems are assigned timeslices during which they are allowed to transmit. It's probably on the order of milliseconds but it seems to me that's enough to affect ping times.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know