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A Study on Regional DSL and Cable Speeds?
antarctican asks: "I'm curious about the typical speed DSL and Cable users get. I see references in various /. articles to speeds such as 128k for DSL connections, to me that seems discustingly slow. Here in British Columbia, Canada a speed of 2-4Mbps for a DSL line (ranging from ~$40-100/month) is the norm, and is easily available in all the major centres. Why are American cable and DSL speeds so low, and where is this artificial limit coming from? It's obviously not the technology!" I don't know that American DSL is necessarily slower than that or not. Your location will greatly affect the kind of broadband access that you can posess, and I wouldn't be surprised if there were some American markets which are as fast, if not faster than 4Mbps. How fast are DSL and Cable lines in your area? Maybe someone can use this information to update the broadband availability charts that are available at various places on the 'net.
Believe it or not, the issue of units naming for bits and bytes has been addressed by the International Electrotechnical Commission (IEC). Though the unit names are not officially part of SI (Systeme Internationale), and the chosen names are unfamiliar, they make a good starting point.
Schwab
Editor, A1-AAA AmeriCaptions
There are several factors that come into play:
Changes in wire type/gauge. Every time you change gauge in wire, you potentially have an impedance mismatch which can cause reflections on the line. These reflections cause certain frequencies (well above human hearing range, but smack-dab in the middle of the DSL frequency range) to be attenuated or altogether canceled out.
Related to this are stubs. Often times, a single line pair leaving a junction box is spliced somewhere along the way and actually goes to two destinations -- one live, one not. This could happen for a variety of reasons, typically due to changes in service at residences near each other. Each stub also causes reflections (worse than those reflections caused by changes in wire gauge), and so this too frustrates DSL service.
Line filters. Strictly speaking, line filters aren't necessary until well down the line, where your voice-band data is converted to digital, or is analog-multiplexed with other signals on a line. To reduce crosstalk and noise (apparently), most POTS lines have line filters closer to the home so only voiceband energy is on the line. These kill DSL dead, as you noted.
Loading coils. On some longer runs out there, loading coils are on the lines to help even out the response curve of the line in the voice band, in part by absorbing reflections. These totally screw up the frequency bands outside the voice band though.
And finally, from what I recall, upper frequences attenuate fairly sharply with distance on unshielded copper, and so the further away you get, the fewer usable frequencies you have to play with.
So, yes, there are a lot of problems as you go from the CO to the end terminal. Some of these problems are in the last mile (changes in wire gauge, stubs) and some are along the way (loading coils).
--Joe--
Program Intellivision!
I see references in various /. articles to speeds such as 128k for DSL connections, to me that seems discustingly slow. Here in British Columbia, Canada a speed of 2-4Mbps for a DSL line (ranging from ~$40-100/month) is the norm, and is easily available in all the major centres
I believe you're confusing 128KBytes per second with 128Kbits per second. Big difference. 128KBps is 128*8 = 1 Mbps, which isn't THAT far off from the Canadian numbers. Note that a T1 is 1.5Mbps
DSL speeds are physically limited by the length of the wiring from your home to the DSL provider's modem. The further away you are, the longer it takes for the signal to propagate and the greater the signal degradation. Using Ethernet cabling as an example (I don't have DSL numbers handy) if you used 10Mbps Ethernet, you could have 2,500 feet between the computers linked together. If you boosted the speed to 100Mbps, your computers could then only be 250 ft apart.
I live in the Boston, USA area and regularly get 1.5Mbps from both cable and DSL. It is possible to get higher DSL speeds (up to a theoretical 7Mbps) if you pay more and are conveniently located very close to a box.
However, most companies here advertise 1.5Mbps because that is the speed they can get to most consumers. It makes for much easier billing and logistics (you know, those non-technical limitations.) If you want higher speeds, be prepared to pay through the nose for it.
However, in terms of regulation, I think that DSL has been friendlier to the subscribers in terms of allowing VPNs and allowing you to run your own servers. A lot of cable broadband providers have really started to crack down on this.
I think speed is only half the issue that is being faced here. It's always nice to pull down a file at speeds over the 1Mbps mark, but with all the rules and regulations, what's the point of having all that bandwidth if you can't use it the way you want?
I'd rather keep my slow 640kbps/90kbps DSL line and be left alone, instead of having an ultra-fast cable modem connection where I can't VPN, can't run a server, and can't have a static IP.
In many instances (AFAIK) in the US, the provider is imposing artificial caps on rates, particularly upstream. The idea as I understand it is to limit the subscribers' ability to host websites and ftp servers off their DSL or cable connection. @Home was lambasted for this last year (see here for more info), especially after a configuration error at the head-end capped downstream rates!
You can find an international cable modem ISP FAQ with service comparisons here if you're looking for more information. It's dated December, 2000, so take it with a grain of salt.
-drin
Hope that helps. HAND. :)
---
"No problem. I have the capacity to do infinite work so long as you don't mind that my quality approaches zero."-Dilbert
I have been watching my download rates for no other reason than to see how fast I'm paying for. what I've noticed is this:
.
I have peaked at about 950 kBps (that's in bytes; in bits, it's ~7.6 Mbps).
.
Now, I don't consider myself an expert, but nearly maxing out my 10 Mbps NIC does not seem slow. especially since I'm only paying for 1 Mbps....
Admitedly, the biggest weakness in this claim is the method used to test the speed. What I did was install gkrellm, and just watch to see what was the biggest number I could get. I turned out that while I was downloading the glibc source, it hit 958 kilobytes per second, and this is the largest number I have seen.
However, it is normal for me to see download rates in the range of 600-700 kilobyte per second.
t14m4t
67.5% Slashdot Pure I guess I need to work on that....
This information is available from http://www.dslreports.com. It has bandwidth information based on provider provided by actual users, but a wealth of other information including installation experiences and tips about network achitechture. Very cool, check it out.
-Matt
I've never heard of such DSL speeds here in Boston, certainly, and my best guess is that the telephone architecture (especially the wiring in houses) is on the average so old (fabric-covered wires instead of twisted-pair) that higher speeds are impossible *in some cases*, so they can't very well offer higher speeds if some of their customers can't take advantage of it. Covad is having enough trouble already, and they certainly don't want the extra hassle of higher speeds.
The other thing, and the more major issue, is *price*. 4 Mbps for $40-$100? And that's probably *CANADIAN* dollars, too. Jebus. I feel ripped-off now.
--nick
Maybe I want slower DSL speeds so I can savor each packet. Have you ever thought of that, Gordon?
Of course not, you were too busy with your socialized medicine and quasi non-violent prime-time tv programming to think of it.
Perhaps you should consider an alternative explanation: your DSL speeds are just as slow (or slower) than they are in the US of A, but special software makes you think your throughput numbers are better. It's all a clever rouse by the CIA to keep you Kanuks up there where we can keep a good eye on you.
Think it won't work? Somebody convinced you that round ham was "back bacon." I rest my case.
-- Sincerely,
A descent, upstanding American
In Canada, I had cable and ADSL (one after the other). Around 1-1.5 Mbps for $40+ CDN a month.
In the US, I tried to get ADSL. No go. Too far away from the CO. Sure I could have 144/144 Kbps IDSL for $125 US a month, but no thanks, too much $$$.
Cable is a no go as well because the whole AT&T cable infrastructure in the San Jose area is about 500 years old and they won't be able to provide the service for between 1 to 5 years from now. But, mind you, I do have digital cable.
This is Silicon Valley, hi-tech mecca of the world - why can't I get high speed Internet access at home???
What did I do? I finally broke down this week and picked up a Ricochet 128 Kbps wireless modem from Fry's. I'm getting 'tween 70-100 Kbps and the best part is I can slap it to my laptop and take it around with me.
There is no 'new' economy, there was no 'new' economy - there is just economy 101 and everyone has to play by its rules - me
When I submitted that comment my query was on the value people were getting for their dollar. Not "how far you are from the CO and the speed you get". Just from talking to American friends it seems our plans up here are better, and I'm wondering why. Maybe because the CRTC regulates such things....
Which is kinda funny, the American "free market" screws out the consumers. In the same way the "free market" has let California power prices now skyrocket, this free market is letting you all be screwed by your telephone and cable providors.
My plan currently is $65 for 4Mbps down and 640k up, and 5 IPs. For $40 I can get 2.5Mbps down, 512k up and 2 IPs. Why are the plan so bad down there? And "the network can't handle it" isn't an excuse, why aren't they upgrading the networks? We can obviously handle it. I usually run into no bottlenecks until I reach the server at the far end of the connection.
Anyhow... maybe it's just the exchange rate... 4Mbps up here in 256k down there. =)
antarctican at trams dot ca