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Alcatel-Lucent Boosts Copper Broadband To 100Mbps
Mark.JUK writes "Telecommunications giant Alcatel-Lucent has today become the first-to-market with VDSL2 Vectoring technology which, it claims, will push the top broadband internet access speeds of existing copper telephone lines over 100Mbps and without needing to bond multiple lines together. Vectoring is essentially a 'noise cancellation' method (similar, in principal, to the technology found in some headphones) that works to cancel out background noise / interference (i.e. crosstalk) and can thus boost performance and reach (coverage) by between 25% and 100%."
The biggest problem of copper is latency not bandwith.
In the consumer market, bandwidth sells, latency doesn't.
Tequila: It's not just for breakfast anymore!
Throttled down to what?
Take Nobody's Word For It.
The problem isn't copper, it's bufferbloat.
Bruce Perens.
There really is no difference in latency between copper and fiber. Fiber runs ~200km/sec which about 2/3 the speed of light. Copper is very similar. Switching equipment causes latency.
Routing and signal processing.
If they're doing a lot of processing as part of their noise reduction, there could be a significant delay added (in each direction)
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"I can't complain, but sometimes still do..." Joe Walsh
With a 40GB/month cap!
It doesn't mean much now, it's built for the future.
Copper is mainly used for last mile delivery not for backhaul. The majority of latency issues which come into play only if you're really a hardcore gamer are to do with routing and switching. Fibre does not fix this problem, actually it may make it worse as routers are purchased which provide more bandwidth with bigger buffers which further contribute to a the bufferbloat phenomenon which affects and degrades routing.
Furthermore your typical ADSL connection to a local game server is 20-30ms. Unless you're the type of gamer who makes their primary career from p4wning n00bs, reducing this figure by 5ms isn't going to provide you with much of an advance. Not into games? What else is there? About the only other really low latency service (and by this I mean service where 20ms becomes significant) is supercomputing, and for grid projects likely to use home internet connections and consumer hardware this isn't an issue.
So my question back to you: Why is it a problem? What are you hoping to fix?
I don't know what planet you live on, but here on earth waves propagate through copper transmission lines at a speed on the order of about half the speed of light. The latency due to a copper cable with a .66 velocity factor over a 10km run is about .050 milliseconds. Considering the latency of the IP network that you're connected to is probably at least 50 ms to even the closest nodes, I doubt a 0.1% increase is going to bother you.
The biggest problem of copper is not latency, it's that you have to lay the fucking cable.
Not really, there hasn't been any real advancements in long-distance DSL since ADSL2's annex L (Re-ADSL2), which cranked up the power a bit to extend the range.
ADSL, ADSL2, and VDSL2 all behave about the same after a certain point. VDSL2 can do 250 mbps symmetrical at source, but after 1600m, it performs the same as ADSL2+, and eventually, the same as ADSL. All these newer DSL standards are really doing is crank up how much spectrum is used, enabling faster speeds at the distances short enough to be able to use those frequencies.
Vectoring helps eliminate crosstalk between multiple DSL lines sharing a bundle of wires, but probably won't make all that much of a difference on long loops, simple attenuation is the enemy there. The real answer to pushing DSL out farther is to push the DSLAM closer, and run fibre to the DSLAM.
No, not velocity factor but rather the problem of copper POTS having crappy channel characteristics and bandwidth, which means that you have to do heavier and heavier signal processing to squeeze ever more diminishing bitrate improvements out of them. And this signal processing takes time, i.e. adds latency, there's no way around that. Case in point; pinging from work to home (250 miles, 10 hops) is on the order of 25 ms. That's with fibre all the way into my basement. (50 Mbps up/down for ca $35/mo inc. IP-telephony.) My DSL way back when was on that order just for the first hop. So that cut my latency in half right there. Now whether that actually matters in the greater scheme of things is another thing entirely. (It's not like the days of modems with 200-300 ms) And it doesn't detract from the buffer bloat problem when links begin to saturate, but that's a different problem.
Stefan Axelsson