IBM Bringing Powerline Broadband Back? 141
KindMind writes "IBM, in partnership with International Broadband Electric Communications, appears to be bringing back
powerline broadband back from the dead.
This time, the idea is to build out in rural areas not currently serviced by broadband, and isn't for competing with other broadband solutions.
From the article: 'Their strategy is to sign up electric cooperatives that provide power to sparsely populated areas across the eastern United States. Rather than compete toe-to-toe with large, entrenched cable or DSL providers, IBEC is looking for customers that have been largely left out of the shift to high-speed Internet.'"
Re:Why others failed (Score:5, Informative)
All of the other efforts failed because it caused interference to ham radios and to emergency broadcast channels.
It had nothing to do with lack of backing, and large corporate backing doesn't necessarily translate to instant success.
Technical problems still exist, why not WiMax? (Score:5, Informative)
Some of the powerline broadband manufacturers were able to produce systems that didn't interfere with public safety and amateur radio.
This is necessary, since even a distant powerline broadband system can interfere with emergency communications - the signals skip off the ionosphere and around the whole world, and sometimes contacts by legitimate radio operators can be made at astonishingly low power - meaning that the power line carriers probably have the potential for worldwide interference.
Earlier this year, ARRL won a suit against FCC that will lead to more realistic parameters for interference. The previous ones applied a single-point interference specification made for consumer electronic devices to any point on a wire, and of course over the total length of the wire the interference power was much higher than the spec.
The problem is that power lines are not like telephone lines or coaxial cable. Telephone lines are carefully balanced so that they cancel out much of the interference they would otherwise generate. Coaxial cables have their own shield. Power lines are driven in unbalanced mode when RF is injected into them, and thus act just like long antenna wires, and they radiate a great deal of any RF sent down them. No amount of signal processing can fix that.
Why not use WiMax? It's higher bandwidth, requires less infrastructure overall to install (since you don't have to bypass transformers, etc.) and works for mobiles. Pretty much every business that has invested in BPL for home internet delivery has failed.
The broadband competition in those areas will end up being between WiMax and cellular.
Bruce
Power line ISP? (Score:5, Informative)
Okay, there's two problems with this, there always have been, and they still aren't practical to solve. The first is transformers. The second is interference.
Transformers: They have a resonant coupling frequency. Try to pass high frequency RF through a power conversion transformer and you get scrambled eggs on the other side. So at every point along the line where you meet a transformer, you'll need an RF pass-thru. These aren't cheap; They need to be lightning resistant, fail safe no matter what (otherwise people die -- no joke here), and in general very well designed. A typical loop is going to see maybe 2-4 step-downs from the plant to your house. At least one RF bypass will need to be installed for each customer, along with whatever CPE is required to get the signal.
Interference: High frequency RF tends to degrade quickly. And above 800 MHz (someone who's an EE, correct me if I'm wrong on the threshold for skin effect) it won't even "stick" to the lines. Because these lines are unshielded aerial lines running in one direction for miles, they make awesome antennas. Which would be great, except... FCC regulations dictate no harmful interference. So any signal being sent down those lines is going to have to be very low power to avoid becoming an omelette with another signal... like say, emergency services. Shannon's law people -- you've got 800 MHz to deal with, a low power signal, and it needs to travel along an antenna some tens of miles along, sucking up every stray RF in the neighborhood. Can you say signal degregation? Any signal you push over that line had better have a helluva lot of error correction. Given it tops out at 3 megabits per second, on a shared link... with 800 MHz of bandwidth to work with... That should give you an idea of just how much the Suck factor is (Low Q for you techies)
So, great article, I applaud IBM for making the effort, but unless you've got some really nifty new electronics, like a DSP from hell, I don't see this being anything but a money sinkhole. Comcast may suck, but they've got a few gigahertz to work with and no FCC restrictions... Just really bad management, which is the only thing making this even remotely practical.
Re:Why others failed (Score:4, Informative)
In short, power is easy to send over Very Long Distances without making it useless. High speed data is harder to send over long distances.
High speed data over copper wire has really rotten distance limits. Gigabit Ethernet reaches only 300 feet, officially. DSL systems get unhappy after 18,000 feet and stop working at all much past 22,000 feet. That's just about 4 miles from the starting point, and not in a straight line. The wire distance includes any ups and downs or detours the poles take.
Compare that to traditional phone service which can go 5-8 miles on a wire, or power lines that can go 10+ miles. Fiber optic can compete with that, but it's costly both for installation and the electronics at each end.
BPL=DOA (Score:5, Informative)
Re:Recently declared extra-dead? (Score:3, Informative)
Re:Why others failed (Score:5, Informative)
In short, power is easy to send over Very Long Distances without making it useless. High speed data is harder to send over long distances.
ROFL
Afaict to get power more than a kilometer or so without crippling losses or insane cable costs you have to run at voltages in the kilovolts, that means either very heavilly insulated cables or tall poles with ceramic insulators on them holding bare wires then lots of small transformers dotted arround (more in the US than europe because the US uses a lower voltage for final distribution to properties)
Data could easilly use a similar system. You install a box that is designed to be pole or outdoor cabinet mounted that terminates a fiber run and distributes services to local houses over DSL.
The trouble is the incumbent telcos can't be bothered doing this because there isn't much money in it and when some locals want to do it theselves they can have problems working with the telco to use the final distribution subloops
take a look at http://www.rric.net/ [rric.net] , a lot of the detail seems to have dissapeared now but IIRC they started off using SDSL over dedicated distribution subloops, then qwest tripled the price of those so they had little choice but to move to shared distrbution subloops (requiring complete new equipment), then iirc qwest for a while took away the ability for them to provision new shared subloops forcing them back to dedicated subloops. I consider that some serious messing arround.
Re:Recently declared extra-dead? (Score:2, Informative)
Sure you can transmit, but good luck hearing anything.
Re:Technical problems still exist, why not WiMax? (Score:3, Informative)