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First Canadian High Speed Internet over Power Grid
oO0(MjB)0Oo writes "Sault Ste. Marie, a northern Ontario town, is going to be the first installation of BPL (Broadband Power Line technology) in Canada. As reported in the Toronto Star, wireless access points will be set up along medium-voltage power lines, providing roaming capability throughout the city to all users."
It's not "over the power grid" in the way you might think, but just WAPs placed along the grid, connected via a fiber backbone. No IP is going along the power lines...
:)
Still great though
this can really disrupt wireless communications notably ham commmunications, power lines make for big antenas
IT is completly "over the power grid".
The "fiber optic backbone" means their network center.
The line says "From wireless, converted to be transmitted OVER THE GRID to the company's (PUC) fiber backbone to the internet."
It is *precisely* a test of data over power lines.
Not just Dilbert - http://www.theregister.co.uk/content/22/35334.html
IP over sewage.
From the article:
:)
"Wyant is quick to point out PUC won't be using power lines to deliver Internet access directly into the home. Instead, the company is installing wireless access points along its medium-voltage lines in densely populated residential areas."
So, no, you won't fry yourself..
but you will have lots of wireless internet to hack into
These wireless "boxes" convert data so they can be sent THROUGH THE GRID...... and onto the company's backbone.
GRID == power grid.
The backbone is not everywhere.. the "backbone" is just somefiber link they have at a NOC to some other isps.
They are indeed using power line data transmission for this... that's what the entire project is about, and the only reason it is significant.
The company supplying the technology is called Amperion. Their website has a description of the kit probably used in the article.
http://www.amperion.com
For those not following the broadband-over-power-lines debate, the basic problem is lack of shielding. Cable modems use coax cable, where the outside of the coax acts as a shield, and so very little RF gets out. The wires carry broadband internet, but don't interfere with anything. In the case of DSL/telephone, you have twisted pair (or at the very least, two wires running very close to each other). They effectively shield each other (meaning that each generates a field in the opposite direction, and the fields cancel out if you're not too close to the wire). More RF gets out than coax, but it's still negligable compared to desirable transmissions. In the case of power lines, they are, depending on power line configuration and frequency, either a significant fraction of a wavelength apart, or several wavelengths apart. In some directions, you get destructive interference, but in others, you get constructive interfence. In the directions of constructive interference, you have a lot of signal being broadcast. As a result, they act as a directional antenna, which interferes with anything on the same wavelengths as power-over-power-lines.
:)
Signal strength goes a square of distance. That means that if I have an antenna running 10 meters from my house, and I'm trying to tune into a station 10 kilometers aways, that station needs to be putting out a million times more power than the segment of powerline running next to me. Ouch.
This probably won't interfere with typical consumer applications (television, FM radio), because if it did, there would be significant political reprecussions, and it would be banned (in other words, it's probably engineered to operate outside of those frequencies). On the other hand, according to the ARRL, it very likely will interfere with amateur radio and therefore emergency communications services.
My view is that it may be a good idea in some third world countries, with no telephone service, where there are no alternatives for Internet. However, in modernized countries, we're better off spending the few extra dollars to put in DSL on top of all phone lines or sticking with modems for a while longer, than in the short term, sacrificing emergency communications infrastructure, and in the long term, entrenching a system of broadband that takes away a significant chunk of the spectrum, and prevents all sorts of innovative uses of that spectrum we haven't thought of yet. Spectrum is a scarce resource, and it's gonna get scarcer. The population growing, but amount of spectrum stays constant, sans a few one-time improvements from better utilization (there are fundamental limits on signal strength vs. noise vs. bandwidth vs. bitrate -- with antenna arrays/directional transmissions, there are limits on directionality vs. frequency vs. transmitter size -- we cannot improve utilization forever). In contrast, all the benefits of power-over-power-lines are short-term -- we only gain the one-time cost of not having to modernize our infrastructure (maintanance costs of the two possible infrastructures aren't significantly different).
I don't know how this initiative works, but my impression is that it sends broadband over powerlines, and then the last gap is sent via wireless. If this is the case, it has all of the standard problems associated above. If not, I need more information than is in the article to evalute it
Sending the data to the transformers (and onto the low-voltage line that enters your house) is probably very difficult and problematic because of the effect of the transformer on the signal. If the data could easily pass through the transformer, you'd think the modem would just plug into a wall socket rather than using WiFi.
Thus, if you had the technology, you could send data through the medium voltage lines if you climbed the pole and hooked it up, but it's very unlikely that the current technology is able to send data through the transformer.
(*) nothing important does NOT include:
Karma? Karma? I don't need no stinkin' karma.
Just so people not familiar with the place know, the Toronto Star is kind of stretching the word "town" here. Sault Ste. Marie has a population of over 75,000 people.
Also, "hydros" in the article refer to the power utilities like Ontario Hydro. "Hydro" (water) comes from the fact that they get some of the power from hydroelectric damns.
----- rL
Wyant is quick to point out PUC won't be using power lines to deliver Internet access directly into the home. Instead, the company is installing wireless access points along its medium-voltage lines in densely populated residential areas.
These wireless "boxes" convert data so they can be sent through the grid and on to PUC's fibre-optic backbone, which connects to the Internet. Home computers equipped with 802.11b or "Wi-Fi" wireless access cards and within 150 metres of these access points will be able to use the service.
The advantage of this approach, said Wyant, is that instead of being tied to home with cable or DSL service, a power-line subscriber with a wireless card can use the service anywhere in Sault Ste. Marie that's within range of an access point.
INTERNET BACKBONE
- connects to -
medium-voltage power lines
- connects to -
wireless boxes
- wirelessly transmits to/from -
subscribers wifi devices.
comment directly in my journal
The frequencies on used all of the commercially deployed powerline broadband systems are in the 2 to 80 MHz range. The Amperion system uses these lower frequencies (often confusingly referred to as HF or high frequency) to distribute the signals across the last mile --except for the last 100 feet or so. It then uses Wi-Fi to make the last connection. The Amperion unit hangs on the medium voltage power line, getting its' power from the same line. This unit converts the HF, last mile power line signal to a Wi Fi signal for transmission to the house nearby.
The only signal deliberately injected on to the power line is the HF signal which is much, much lower than a 2.4 GHz. Wi-Fi signal.
Even using so-called HF (high frequency) signals (3 to 30 MHz.) on power lines is tricky -- that's one reason we didn't see this technology 10 or 20 years ago. The signals attenuate rapidly and need regeneration every several hundred or thousand meters. To the extent that the power line picks up some of the Wi-Fi signal, attenuation is much higher at 2.4 GHz.
Most radio frequency concerns associated with these systems focus on possible interference to military and amateur radio operations in the HF range, not other 2.4 GHz. devices.
Al Bonnyman
Community Broadband Networks
See that cool remote weather station widget you got, with the remote outdoor sensor? Probably uses 450 MHz to report the outside temp back to the main unit. Baby monitors. Cordless phones, except maybe digital spread spectrum ones. Wireless burglar alarms. Etc etc etc.
All exist by the grace of FCC rules, part 15, which says, "This device must not cause any interference to any other device, and must accept any interference from any other device." That means that if you pay money for it, get it home, and the RF hash from the BPL outside your window blankets the range used by it, and it's useless, you got nobody to cry to. Refer to part 15, FCC rules.
Ok, now, Ham Radio, licensed under part 95 (or part 97? Can never keep that straight) is DIFFERENT. There are specific portions of spectrum carved out and devoted to amateur radio as PRIMARY use bands. If you are not licensed by the FCC under part 95, and you interfere in one of those bands, YOU are required to shut it down.
Lo and behold! BPL in the US is a Part 15 licensee. Guess what? A ham files a notice with the FCC and East Podunk Power Light & Internet needs to punch the buttons that shift the BPL carrier to another set of bands. Then the country sheriff's non-trunked 435 MHz (or whatever) radios become useless in certain areas. A few more notices, a few more shifts, and if they can't stay out of bands they don't belong in without radiating all over the place, and the FCC shows up and says, "Turn it off."
And how tight and non-radiating do you think those rusty bolts and cable clamps are, out in the weather, some of which were last inspected in 1952? Not very, I'll wager. Ever stand near (not UNDER!) a high-voltage distribution tower in wet weather and hear the continuous sizzle? And you think THATS RFI tight??
Call me dubious.
The Amperion unit on the pole uses Wi-Fi through the air for the connection from the pole to the house. All the subscriber needs is a Wi-Fi unit of his own.
There are other power line broadband systems from other vendors that use a special proprietary modem that plugs into the 120v outlet in the customer home and has an Ethernet output.
Al Bonnyman
Community Broadband Networks
If you check one of those common Ontario Road maps, with one side "Northern Ontario" and the other side "Southern Ontario", you'll notice that the scale on Northern Ontario is smaller than that of Southern Ontario. Yet the Sault sometimes just barely appears on the edge of the Southern Ontario map, but also appears on a Northern Ontario map... but the scale is different!
The Sault is indeed at a more southern latitude than Seattle, and it is indeed geographically well in the southern half of the province.
Detroit is at 42 degrees,
Fort Severn is at 56 degrees,
The Sault is at 46 degrees,
Seattle is at 47 degrees.
Granted, most of the time when people are speaking about Southern Ontario, and Northern Ontario, they're drawing the border somewhere along the population rather than the geography. It strikes me as silly though when Ontario-U.S. border towns are considered in Northern Ontario.
The Northern half of Ontario is absurdly large.
"They are not transmitting shit over powerlines. They are transmitting over a fiber optic network which they installed with the power lines, then using 802.11b for the "last mile" to the consumer homes.This is not the same thing as the internet over power line debate, with all of the shielding and signal issues."
Wrong!!
The Amperion system uses RF signals injected on the power conductors for the 'last mile' to the Amperion unit on the conductor that then transmits it through the air as Wi-Fi the last 100 feet or so to the subscriber.
Some broadband over power line (BPL) systems use fiber for 'backhaul' from the injection point (often at a substation) to the utilities routers. For instance, City of Manassas Utilities is doing something like that using AFL equipment. The last mile on that system is BPL, however.
("Last mile" refers to the run from the narest aggregation point to the subscriber -- it can actually be more or less than a mile)
Al Bonnyman
Community Broadband Networks
Sault Ste. Marie... Northern Michigan, SOUTHERN Ontario. and Int'l border.