155Mbs Over Copper Lines 122
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.
Re:But we've had that for years : ) (Score:1)
Another Article (Score:1)
Re:I probably can't get this, either (Score:1)
Damn, I'd just settle for 640k DSL.
Nobody will ever need more than 640k DSL!
Re:I probably can't get this, either (Score:1)
Re:I have never heard of this 'mbs' before... (Score:2)
1/1000(or is that 1024?)th of a bit per second.
155mbs over copper is a piece of cake! We had those speeds years ago.
Forget fiber.. (Score:3)
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.
Re:I have that too (Score:1)
I have that too (Score:2)
Re:This technology is old. (and other assorted ran (Score:2)
http://www.qwest.com/about/qwest/QwestCyberCenters /NA_IP_Network_map_large.jpg [qwest.com]
http://www.above.net/network/index.html [above.net]
It's wonders what you can do when you also own the dark fiber/DWDM gear... Split a few lambdas off for yourself, sell the rest to cover your costs... Not too bad if you can afford it.
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Re:Fiber to the home will never happen. (Score:1)
"We have the right to believe at our own risk any hypothesis that is live enough to tempt our will."
Re:Fiber to the home will never happen. (Score:2)
All the widespread existence of ridiculously fast connections to the backbone will yield is a ridiculously clogged backbone. Running fiber to businesses and homes will just push the bandwidth block back a step. It won't fix jack.
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Re:But we've had that for years : ) (Score:1)
Cat5e is rated up to 350Mhz and can handle 1Gbit. 1000Base-T runs over Cat5e, and it is indeed copper.
Re:I have never heard of this 'mbs' before... (Score:2)
Re:Could this tech be used.... (Score:2)
Re:I have never heard of this 'mbs' before... (Score:3)
Living on the wrong end of the last mile (Score:3)
(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.
Nice tech, one that we will most likely never see. (Score:2)
I don't see telco's ever offering this service. Look how long they've drug their feet with DSL and the like. Hell ISDN has been out since the mid 80's, and telco's still can't seem to get it installed right. (At least Ameritech can't) DSL? Hell my ex back in 97 was beta testing ADSL from Ameritech in Ann Arbor, and yet years later, Ameritech has yet to fully roll it out. Honestly, how hard is it to support? Just add a few boards into the telco switch and volia, you have support.
If this was something that was available and at a reasonable price, it's something that I can see many many people picking up. I'd of course be in line for that much bandwidth. (Voice over IP comes to mind). But knowing how slow and lethargic telcos are, it will be at least 2010 before you start seeing anyone in the US with this service and much much longer before it's available nationwide as well as globally.
</rant>
--
"If you insist on using Windoze you're on your own."
Re:Fiber to the home will never happen. (Score:4)
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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Re:Fiber to the home will never happen. (Score:1)
This presumes that the bandwidth throughout the world is the same as when we were all using 14.4 modems (and apparently those of us with high speed connections are doing so at the expense of those with low speed connections?): Nothing could be further from the truth. The reality is that the backbone speeds of the net have gone up astoundingly (indeed there is lots of dark fiber out there waiting for the need). I get 200KB/second pretty much all day downloading from a good number of sites, and that number is purely an artificial limit in my cable modem.
Roomate's getting nookie (Score:4)
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.
Re:it's called Spatial Division Multiplexing at 45 (Score:1)
Re:it's called Spatial Division Multiplexing at 45 (Score:1)
End of news, not even innovative for people not completely in the field...
Re:it's called Spatial Division Multiplexing at 45 (Score:1)
method. It's basically dividing a space up into several channels."
Sure, just like HADM (Horse Ass Division Multiplexing) is. If they give it a nice name, that doesn't mean it means something nice.
The local loop copper is a twisted pair and is in no way comparable to fibre or coax (cable). Copper is copper, and in one pair, there is no 'space' to put channels next to each other (even the skineffect is frequency-dependent). The only way to do that is to bundle multiple pairs. Yeah right, groundbreaking technology my ass (or the horse's for that matter).
Your cable modem might top out at 2Mbit, but the protocol used puts 30Mbit in the same frequency band as one single TV channel. You're just not getting it all on your modem.
it's called Spatial Division Multiplexing at 45Mb (Score:2)
They seem to have already tested it in the field, which explains the funding.
On another page of their website they mention a bit-error rate (BER) of 10E-10, one bit error per 1 billion bits at 10-100Mbit/s.
All they're saying that they are 'controlling the crosstalk interference'. Maybe they're just the first to try that, or maybe they did some advanced crosstalk modeling. I wonder how well that works if the crosstalk is caused by another SDM line?
Will this be another bluetooth? Works well in the lab, but when you cram a couple of devices close together it doesn't work as well?
Re:obligatory (Score:4)
shoulda
lotsa
Goodness. Jar-Jar is trolling
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But 155 over copper will never happen either (Score:1)
The big advantage of fiber, if it happens, is that it is a technology designed for data, and BW is limited only by how much terminal electronics you can afford. My question is, who is going to provide it? The traditional Telcos have failed, and the cable companies aren't much better.
The last mile is always going to be a problem. Wireless is way to bypass that. Maybe when we get 4G wireless networks...
-Lost in CT
Re:I cant agree... (Score:1)
Re:I have never heard of this 'mbs' before... (Score:1)
Cool... (Score:1)
It is nice to see the existing infrastructure being reused though, fiber to the home [at any speed] is going to take a LONG time to become as widespread as the copper telco networks, if it ever happens...
Re:Cool... (Score:3)
Re:Fiber to the home will never happen. (Score:2)
The high price of your tiny cable is not because of the fiber, but because of the connectors (5-10 bucks each, IIRC) and the labour, which was jacked up because fiber guys are very well paid.
Anybody can get a Cat5 crimper and a bag of cheap-o connectors and start cranking out cables. I've done fiber work and the equipment is *very* expensive, not to mention the attention to detail it requires to keep your signal losses minimised.
Re:How clever ! (Score:1)
I think they're usually aluminum (copper is 'spensive).
Power delivery over IP is the solution (Score:2)
There is hope for the people of Fremont.
the AC
Re:it's called Spatial Division Multiplexing at 45 (Score:2)
So they pump copper to its limit, do it over a bunch of pairs in parallel, and get a lot of bandwidth in the aggregate. Big whoop!
There is some effort needed in controlling interference, because most DSL technologies are mutually interfering, and degrade in speed when the subscription rate increases. But it's not going to give you 155 Mbps over a 5-mile loop from the CO to your house. Never will.
Re:I probably can't get this, either (Score:2)
It's so nice to live in a small enough city that doing a complete rebuild of the cable system is actually feasible.
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Re:It,s all nice, but... (Score:2)
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Re:Fiber to the home will never happen. (Score:3)
Don't go putting Canada down. It's only 40% of our income...
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Re:Roomate's getting nookie (Score:1)
Re:Fiber to the home will never happen. (Score:1)
Re:But 155 over copper will never happen either (Score:1)
Re:Nice tech, one that we will most likely never s (Score:1)
Re:Nice tech, one that we will most likely never s (Score:1)
Re:hich means... (Score:1)
100 meters vs. The Last Mile (Score:3)
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.
Is this such a good idea? (Score:1)
Now imagine what happens when you plan the backbone around expensive fiber optic lines, costs charged by backbone providers for bandwidth and traffic utilization incurred by smaller ISPs, and a customer base using correspondingly smaller connections which, when aggragated, use up a big chunk of the big pipe while allowing some room for spikes in traffic, customer growth, etc. That all sounds pretty managable, right? Now imagine what happens when you give the users a connection that rivals what chunks of the backbone can do, eclipse the rates attainable by interfaces on routers, switches, and servers. Imagine what kind of damage someone like Mafiaboy [internetweek.com] could do? Imagine what kind of capactity problems you'd see just from normal usage?
Ok, now, ummm (Score:1)
Re:Nice tech, one that we will most likely never s (Score:1)
satisfied.
Ok, I don't really think I have anything useful to say...
--Josh
155 Mbps over copper? Not in our dimension (Score:1)
1) Is our current understanding of "physical upper limits" of a medium such as copper a correct one? IE: Are we considering all variables when coming up with an upper limit. Past experiments have shown that (possibly constant!) factors such as quantum-level cross-talk may cause us to re-evaluate past limit measurements and scale them with respect to these until-now undectable, unavoidable "noises."
2) If we ever do find a suitable upper bound, how will factors such as "Information Entropy" allow co-existence between a medium's electromagnetic spectra emissions and future attempts at compression via medium microdeformities?
The audacity of this article is quite unnerving. But like the poster said, it wasn't exactly technically based.
Do they need a test bed? (Score:4)
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
Re:But we've had that for years : ) (Score:2)
Re:Do they need a test bed? (Score:2)
Re:I have that too (Score:2)
Re:Cool... (Score:2)
VERY wel put! The nearby ISP here pays $13,000 per month for each of their upstream DS3/T3 connections (45mbps to UUNET/Worldcom). OC3 is 155mbps and is in the neighborhood of $35,000 per month.
Re:Fiber to the home will never happen. (Score:2)
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Fiber to the home will never happen. (Score:3)
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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Re:Cool... (Score:1)
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Re:Fiber to the home will never happen. (Score:2)
And that's without laying more. When the fiber gets full, they can lay some more fibers next to the existing one. It's not like it takes up real estate like building roads does.
As long as the users demand more bandwidth and are prepared to pay for the bandwidth then the backbone is going to continue to grow. That's the bottom line.
Re:Fiber to the home will never happen. (Score:2)
The bust comes about because for every dollar invested, they were getting 50 cents back. Currently they can't borrow money. If you can't borrow money your business is in big trouble. They just can't afford to buy the boxes to stick on each end of the fiber right now.
That's what's happening. It's a financial, not a technical issue.
Re:Nice tech, one that we will most likely never s (Score:2)
Actually it is no where near that simple. There are a lot of problems with rolling DSL service out, and most of them are a function of lack of resources. Ameritech in particular lacks the manpower and cable availability to properly support a rollout of DSL.
Let me see if I can explain why a little bit. Back in the day (~15 years ago and earlier) the local telco would provision for basically 2 lines per household. At some point, shortly before the explosion in popularity of modems, cell phones and all the other toys we love to use, it was decided that this was wasteful and that fewer lines would be provisioned. This meant that that new subdevelopment would have only a minimal number of extra lines available to it. This also meant that once folks started using extra lines for modems, working at home, and the like, that upgrading them was no longer simply a matter of adding a few switches. Now they had to go and dig up that line and add more lines.
But it gets worse. DSL only works when the customer is close to the central office and when they have an uninterrupted connection to it. If they don't the line has to be "conditioned" to make it work. Have a bit of fiber cable between you and the office? Chances are you'll never get DSL any time soon. Conditioning the line is expensive and time consuming. Since the phone company isn't going to eat the cost of doing it so they can take a loss by billing you for $40/month which is much less than the several thousand dollar cost of doing the line.
Even if you are all set up from a technical point of view, there still are the issues with getting the equipment on the user's computer to work. The phone companies are simply not experienced in or set up for supporting end users with complicated copmuter equipment. Phones are easy, computers aren't. Remember, the local telco is still esentially a monopoly and has the same bureacracy and mentality of one even 20 years since AT&T split. I've seen it first hand. Anyone who thinks that these companies became nimble and customer responsive just because AT&T was broken up has zero knowledge of how they work on the inside. They are still not set up to hand customer service on the scale DSL requires.
There's a lot more to it than this but I'm tired of typing. Point is, there are a lot of issues we as customers don't generally see. General DSL rollout is going to take a LONG time. Learn to live with it.
Re:So Simple (Score:1)
1 bit represents two possible characters. 2 bits represent four possible characters. 3 bits represent nine possible characters. 4 bits represent sixteen possible characters
...if the 64 bits is broken into 8 bit words it can only represent 512 unique characters.
Looks like a crank. Or just a Troll ? Nevertheless this is total nonesense - dont bother.
Re:hich means... (Score:1)
Enigma
Re:Do they need a test bed? (Score:1)
which is exactly why it's totally worthless to people who play games (lots of people)...
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Re:Cool... (Score:2)
Steven
Re:Cool... (Score:1)
This technology is old. (and other assorted rants) (Score:2)
1) This technology already exists. It has for a while. It's called HDSL. When we need bandwidth at a remote site that is not fibre fed, we will install HDSL shelves to carry the payload. Install enough of them, and you will get your 155MB/s rate.
2) All the people that are whining about "I live in the city, less than 10,000 ft from a C.O., and I can't get DSL." . YOU may live 10,000 ft from the CO, but how far does that wire that feeds your house extend PAST your house. It may continue on for a mile or more past your house.
3) People who say "X" company has an OC-192 connection. No, actually they don't. Show me a company that has a OC-192 connection, and i'll show you a company that is blowing smoke out their ass. OC-192's (and recently OC-768) and the DWDM technology are used by Telco's as backbones. Do you really think a Telco is going to allow one of their backbones to be saturated by ONE customer?
4) Fiber to the house. Unless your house was built with it, don't expect to get it. The costs would be ASTRONOMICAL to lay a fiber to every house that currently has copper. Opening trenches is VERY labor intensive. (read:$$$)
5) To put DSL in a CO, its "just a couple of cards in the telco switch". WRONG. The whole point of DSL (other than speed increase), is to offload the processing/routing of the data away from the voice switch. To put DSL into a CO, they have to install an entirely different piece of equipment, called a DSLAM (Digital Subscriber Line Access Multiplexer). This box strips off the higher frequencies containing the data traffic before it hits the voice switch and routes it over the telco/ISP's ATM network, freeing up resources in the voice switch which would otherwise be dedicated to dial-up connections.
6) "It would be cheaper to use fiber than copper, because of the cost of a CSU/DSU and the setup." WRONG. Do people think that you can just plug this fiber into a fiber modem and BAM!, you have an OC3? THE most expensive part of a dedicated fiber connection is the ADM, which sits at the customer end and pares off/adds on the customers traffic from the other traffic on the ring or linear connection. (Add/Drop Multiplexer) The cost of a ADM is substantially more than that of a CSU/DSU.
7) And finally, to the person who stated "Forget copper, I want to get SONET". You can get SONET over an electrical connection (read: copper), its called an STS-x connection rather than an OC-x connection. I believe the STS-x connections now have a rate as high as STS-12.
/end rant.
Re:Bandwidth costs money (Score:1)
I would be real curious to see pricing on an ISP end to see what it actually cost to have a full time, say T3 or whatever your average mom and pop ISP uses.
Re:Bandwidth costs money (Score:1)
Re:Bandwidth costs money (Score:1)
With Napster, et al, it seems like ISPs, Universities, etc. were complaining about all their bandwidth being used up - is it just because everyone had a fast pipe on their desk instead of a modem?
How clever ! (Score:4)
Re:That's nice, but... (Score:1)
Re:Cool... (Score:5)
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.
Re:it's called Spatial Division Multiplexing at 45 (Score:1)
"By boosting the speed, range and reliability of copper, carriers can offer affordable, same day provisioning of DS3+ services (45 Mbps symmetrical transport) to virtually any copper fed Remote Terminal (RT) cabinet or Multi Tenant Unit (MTU)."
These speeds are not too a particular house, but to RT's and MTU's. In other words, to places like office buildings.
Further down:
"Additionally, transforming multiple copper pairs into a DS3 backhaul to bring the power of the fiber backbone to the final rural mile will make universal broadband service a reality sooner than anyone could have imagined."
"Multiple copper pairs into a backhaul" -- So it sounds like they are taking a bundle of between 25 and 50 and turning it into a 45 to 155 mbps link.
Still, this is pretty good. Right now, you get nearly a T1 (1.544 mbps) worth of speed out of 50 wires (25 56K modems). So 45 - 155 mbps is a big improvement.
Re:100 meters vs. The Last Mile (Score:2)
Re:It,s all nice, but... (Score:1)
Re:But we've had that for years : ) (Score:1)
1. cat5 is twisted (don't recall the interval), telco wire is not necessarily twisted. This makes a big difference on cross-talk.
2. telco patch boards are not engineered to prevent cross-talk across connections at the box.
There are probably other significant differences too.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ the real world is much simpler ~~
obligatory (Score:2)
waittta minute....
sorry wrong obligatory....
shoulda been:
lotsa more porn...a video for each of my monitors....
News? (Score:1)
Oh wait, you mean the copper in my telephone line? Yes, well that's a little different story, isn't it? Now who's stupid?
joke man, joke.
~
Re:News? (Score:1)
~
Re:Forget fiber.. (Score:1)
Corollary: By and large, the masses are more than willing to pay premium prices for grabage. The proof? It's called Windows. And Survivor. And Verizon.
Sigh... life is a comedy. (Or is it a tragedy?)
Re:Do they need a test bed? (Score:1)
Re:Do they need a test bed? (Score:1)
Re:Cool... (Score:2)
I suppose the TCP window would only get big enough for you to clock a speed like that if you were downloading a...let's see...a large binary image? From a newsgroup?
And just where exactly have you been hanging out on this "Internet," young man?
Re:Forget fiber.. (Score:1)
Re:Picky, Picky, Picky SPQR (Score:1)
The Senate and the Roman People. Or does this mean something else in /.-land?
What good is this technology... (Score:1)
Clearly, it's not cheap to drop a new building with late-model gear, fight the local regulatory battle for rights-of-way, and lay a better network around your favorite navigational hazard (Verizon, in my case) but I'm surprised at how impossible the task seems to be.
Balls, man: if you want to destroy your wetware, you can get all of the hard drugs you want, and they're not even legal. Broadband, which any wired person would want, seems as difficult as finding decent political candidates.
Re:Picky, Picky, Picky SPQR (Score:1)
Re:That's nice, but... (Score:2)
Don't feel too sorry for yourself. Because of crappy wiring, I max at 31.2k, and I live in a VERY large college town, with a population of 200,000!
Re:How clever ! (Score:1)
are powerlines copper? :) sure, they are nice thick cables with a heap of twists per metre - would it be feasible for a telco company to hook into unused power lines to provide network connections. as for blackouts - thats what UPS is for, or, use a laptop!
Flawed Thinking (Score:2)
I wouldn't assume that the average phone/cable company employees are too dumb to lay fiber. I've seen wiring jobs by the telco, and they quickly approach a degree of complication that I don't want to mess with. I've also seen the tools used by telco employees, which seem to have a level of sophistication that monkeys would be unable to use.
Its like assuming that since I can use the new iMac at home, those network admins in the back room must not require that much training. Hell, its just a computer, you turn it on or off, what more do you need to know. :)
Re:I have never heard of this 'mbs' before... (Score:1)
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www.shockthemonkey.org [shockthemonkey.org]
Re:obligatory (Score:1)
I thought I'd try to save ya', don't worry!
ALL YOUR FANCY BANDWIDTH BELONGS TO US!
Re:That's nice, but... (Score:1)
Cincinnati... okay multiple stupid topic. (Score:1)
But back on topic. Here in Cincy [where Carmen Electra is from] we've had DSL before it was a buzzword you'd see in every Ziff Davis mag. We had cable in limited areas for a while, but upgraded pretty fast. Time Warner rebuilt the whole network, at least thats what I got from the letters you'd see tacked up in apartments and such.
I'd say were pretty quick to get 'broadband' access here, not like Cali, or Tokyo, but we get it pretty fast. Our local Telco [Cincinnati Bell, Duh?!] was even featured in some crappy Ziff Davis mag for their 'Internet Call Manager'.
What was the point? Oh yeah, if you want broadband, come here. RoadRunner Business Class, SDSL [downtown only, i think], ADSL
But I'll move where this gets implemented first.
My question is, why do we need a 'last mile' solution in this day and age? Why aren't we moving away from clients and get into complex networking of home users computers? Computers are getting more powerful, and more people are buying computers. Why does the internet community [big guys] not demand more from the home user?
Re:That's nice, but... (Score:1)
Re:it's called Spatial Division Multiplexing at 45 (Score:3)
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.
Re: (Score:2)
But we've had that for years : ) (Score:2)
The article had me going for a while as I tried to figure out what the big deal was, I mean, we've had 1000Mb for copper for years now : )
Re:But we've had that for years : ) (Score:2)
Furthermore, Gigabit speeds over Cat5 cable degrades after as little as 200 meters [peakaudio.com]. Unless you live within 200 meters of your telco's co this is not of much use.
hich means... (Score:2)
Screw 3...
Re:Do they need a test bed? (Score:2)
To my way of thinking, the primary problem to be solved is that of realising decent upload speeds without using an inordinately large dish. It surely can be done, however.
If sattelite access ever does achieve its potential, it will (at least potentially) allow for true competition in the market, unlike the halfway government sanction monopolistic crap we have to deal with, wherever we are, now.
In the meantime, though, I'll have to simply dream of living in the middle of nowhere with a decent connection.