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155Mbs Over Copper Lines
FIGJAM writes: "Actelis, based in Fremont, California, have raised $26 million to enable speeds up to 155Mbs over copper lines by overcoming crosstalk interference with error-correction." The article is unfortunately short on technical details, long on current telecom market financial conditions. There's a bit more information on their website, but be warned, it's nearly as buzzword centric and glib. The speed of fiber over existing copper is still too tantalizing to ignore, though, even if it's not as sexy as actual fiber to the home.
Fiber optic cable is not just another type of wire. It's much more difficult to work with, and installation (on a large scale) requires more skill than your average phone/cable company truck monkey posesses.
Besides, what in the world would make communications companies WANT to do such a thing? If the current broadband market has shown us anything is that residental internet is a suckers game. There's no profit in it.
I have the first issue of Wired magazine, and there is a brilliant column (back page) by Nicholas Negroponte (of the MIT media lab) -- he makes a fairly profound and accurate statement: by in large, the massess are not willing to pay extra money for extra quality. The article was about HDTV an his assertion was that it would never catch on (by market forces alone), unless the government forced it on us via regulations.
The same can be said of broadband -- the masses are overjoyed with AOL and MSN...the rest that arent arent big enough of a market to bother with.
mbps=millibits per second. 6000 mbps would be 1 bit per second, meaning about 10 seconds, including overhead, to transmit one byte.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
(In the case of power lines I don't mind it so much. 60 Hz 120 volt AC is pretty much the same no matter from whom you buy it. The company from whom we buy electrical power is the same company from whom we buy delivery of that power. If we were buying power from some company other than the one that owns the wires that run to the house, the people with the package deal would probably get any of their problems dealt with first.)
I'm a lot less happy that our choice of cable TV providers is either Time-Warner or Time-Warner.
I'm beginning to wonder if the local telco (Carolina Tel&Tel as swallowed by Sprint--they've been saying "real soon now" on DSL for a couple of years) isn't waiting for Road Runner to put all the (few) local ISPs (which are all owned by regional companies now anyway, my account's been absorbed twice so far) out of business before they offer DSL so that they can be the only ISP available over DSL, and then they'll undercut cable by a few bucks to steal some Road Runner customers and grab all the new ones that come along.
I wonder if a lot of people will stay with cable anyway (I'm sure TW will offer some sort of TV/Internet package deal and make up the difference overcharging cable-only customers) just to avoid changing their email addresses.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
In Canada, the telcos generally lay fiber right to the foundation wall of new homes.
:-)
They're laying copper to homes anyway, and the big expense isn't the fiber -- it's cheaper than copper -- but installation. Expensive to dig trenches, lay conduit, and all that shite. Costs damn near nothing to toss a bit of fiber in the pipe at the same time.
So there's a lot of dark fiber out there, just waiting for the profitability point to make it worth it for the telco to turn it on.
You should move to a modern country. We've got ADSL all over the damn place. Can't get away from it these days...
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Hmmm, I'd personally rather have fiber. Why would I rather see fiber widely distributed? Because it is multifunction. A single fiber line can carry hundreds of TV channels, tons of voice channels and even data channels for us internet users. Coax could do the same thing if cable companies and telephone companies were allowed to be a little more friendly with one another (ergo, getting higher throughput on copper means it could compete with fiber thus this article is is interasting however this is pushing the limits of copper wiring's data rate while optical fibers still have room left for bandwidth). Using fiber networks wouldn't necessarily destroy the country's backbones either, if anything it would spurn the usage of higher data rate routers and lines. IIRC the fastest backbone in the US is the OC-192 between Chicago and St.Louis owned and operated by MCI. RUnning fiber to homes and businesses is not going to automatically mean they've got an OC-3 in their garage. The owners of the fiber would just allocate data channels (just like on copper lines) and sell them to whoever wanted to use them. Video could be transmitted on channels a-b whilst data/voice is allocated to channels c-d with e-f (the letters obviously represent ranges of individual data channels) reserved for other usage. Wiring inside houses could easily be preserved by connecting it to a small autonomous bridge in a box on your garage. I could envision fiber to homes but this is marred by the reality that cable companies and telephone companies are both pretty stingy and the only real way to get fiber to the home is for the government to do it and control the lines themselves letting others fill them with content.
This brings up an interesting point, should municipalities get into the fiber game? Not for profit but merely to seed the technology's availability, especially since private organizations are not willing to do it. Routine maitenance of sewers, streets, and power grids could be used to lay dark fiber for later illuminating. If the process was tacked onto work already being done it could be made cost effective and it offers greater local competition for service. You'd get the fiber run to your house and opt to either keep your existing copper service to upgrade to fiber. With bridges linking the copper in your house and the fiber outside you wouldn't need to spend several thousand dollars on new equipment right off the bat. I guess I'm warm to the idea because my city has a municipally owned electricity company and is thus fairly exempt from the troubles of the rest of the state's privatized electricity generators.
I'm a loner Dottie, a Rebel.
waittta
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shoulda
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Goodness. Jar-Jar is trolling
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"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
Good point... even if these can get out to homes at reasonable prices, this is gonna be worse shared bandwidth than cable modem technology; cables are 4mbps average (around here anyway), sharing a couple T3's or maybe an OC3 for larger area isn't that bad - but one of these copper links is the speed of just one of those kinda-expensive OC3's, and i don't think the phone companies are going to be too eager to install huge pipes to fully take advantage of a 155mbps link to each home...
Don't go putting Canada down. It's only 40% of our income...
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...or actually something like 15,000 feet, which is the telco's DSL limit.
I'm no telco guy, but I know a couple and dimly recall conversions like '...some people are 40,000 ft or more from the c/o...' and '...the signal quality decreases rapidly when the DSL limit is reached'
1 Gbit @ 100 meters is here now. But if you recall from geometry, the area of a circle increases rapidly with the radius, so you get a lot of population outside the current DSL limit...and a horrendous amount outside the 100 meter limit.
This technology could change all that.
Treatment, not tyranny. End the drug war and free our American POWs.
Treatment, not tyranny. End the drug war and free our American POWs.
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Because where I live, my connection is the equiv. to a post-nuclear wasteland... I don't know if that made sense..
anyway, 26k dialup is all I can get.
no 56k
no cable
no dsl
no 128k ISDN, but I can get 64k ISDN for $115 a month.. don't think so
wireless, I don't know yet.. probably not, considering I have trees around me
satellite, high latency sucks
tin cans and fishing line, I don't have enough to reach that far
I hate the internet,
Klowner
Sorry, but you can stop holding your breath. Fiber is an excellent backbone technology but it's too cumbersome, expensive, and difficult to deploy to ever become a "last mile" solution.
People clued in long ago that fiber to the workstation on corporate LANs was far more expensive than copper and offered no speed increases. Fiber to the home is the same -- it's cheaper to just install better quality phone cable or find better transmission methods for existing cabling. Why spend all that money on fiber?
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Cool, people in Fremont will be able to get high speed Internet through their powerlines during blackouts.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Unfortunately, the link to the home is just one of the bottlenecks. I've had a cable modem for a couple of years now, and speeds still suck. It isn't because of the wire to my house, either; downloads from @Home's newsgroups, which are hosted on their own servers, hit 3-4Mbps. For most downloads from non-@Home servers, it's rare if the speed exceeds 300-400 kbps. The servers themselves and paths on the internet at large are going to have to be improved for high-speed access to really meet its full potential.
"If I have seen further than other men, it is by stepping on their glasses." - Michael Swaine
Spatial Division Multiplexing is just another way of assigning specific areas to transfer data in parallel, instead of using a serial transfer method. It's basically dividing a space up into several channels.
I know you can do this in optics: for example, use only one part of an optic for a specific channel, etc. but since copper is conductive you can't define boundries, which is where I assume the cross talk correction comes in.
However, SDM is very inefficient for copper networks. A cousin, frequency division multiplexing, which is used in optical networks, DSL, cable networks (frequencies divided up into channels) is much better suited. Fiber uses it as well.
Time division multiplexing is also used, and on high capacity optical pipes DWDM systems are used which multiplex channels over several wavelengths, which can also 'layer' FDM and other modulation and frequency style methods to get even more bandwidth. A single optical fiber has as much bandwidth as the diffraction and interference limited wavelengths seperation times the data frequency. You could very easily fit all the world's Internet traffic onto a single fiber using a very sophisticated DWDM-FDM (with wavelength spacings at the physical limits). But then you need to be able to seperate each very close wavelength out, and demultiplex the several GHz modulation of each thereof (picosecond response, anyone?). Not to mention the generation which involves inverse problems of the same nature.
But as far as SDM on a copper line, this is defeating its own purpose. IMHO, its better to have a high clock and go up in bandwidth on the line. Copper can handle 100's of channels of UNCOMPRESSED video, just look at your cable system. Your cable modem can barely handle 2 Mbps, which is a far cry from raw NTSC. We aren't even using a fraction of that for gigabit networking fiber-over-CAT5 as it is.
This may be an interesting method, but it's a step back. It might be good if it can do it over all the ancient POTs stuff and go to consumers, but then again it relies on self-correcting cross talk and interference models, which can only be taken so far and are only ideal in *ideal* conditions.
What we really need is a good CAT5 going to every house providing all data services, and DWDM hubs to transfer and enable dedication and not bandwidth sharing. But as someone else mentioned, the telco's like to keep us in the dark ages, so they can milk out as much as they can from their nth generation system. They'll take it for as long as possible, before they're forced to get up and realize those research dollars back in the 1960s have long since been payed for.
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