Broadband over Power Lines under pressure

BPL is essentially Wi-Fi over power lines, except that the frequencies in use, can cause interference with HAM radio, and would-be emergency frequencies.

The American Amateur Radio League has a whole host of info around it.
http://www.arrl.org/bpl/

All the 200Mbps claims are really just that. It's like expecting a WiFi router that is advertised to do 108Mbps to actually live up to it's claim. You can do it if you're two inches from the router.

Depending on the noise that your refrigerator, TV, RADIO, Microwave and other peripherals cause on the Power line, real-world speeds are actually in the order of 10-30Mbps, or less.
 
Surely this technology is on the obsolete side? i mean there is 3g/hspda and wifi/wimax? Al this sounds like there is more effort involved in getting it going that it's worth.
 
TheRoDent said:
BPL is essentially Wi-Fi over power lines, except that the frequencies in use, can cause interference with HAM radio, and would-be emergency frequencies.

The American Amateur Radio League has a whole host of info around it.
http://www.arrl.org/bpl/

All the 200Mbps claims are really just that. It's like expecting a WiFi router that is advertised to do 108Mbps to actually live up to it's claim. You can do it if you're two inches from the router.

Depending on the noise that your refrigerator, TV, RADIO, Microwave and other peripherals cause on the Power line, real-world speeds are actually in the order of 10-30Mbps, or less.
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And in general we have more noise on our lines in SA thanks to two pin plugs not being keyed. Despite contrary belief, it does make a difference which polarity you use when connecting 2 pin devices - if they are all the same, you should have negligible noise, if not, you will have plenty. My Tivo from the US has a figure of eight cable where one side is square - i.e. keyed... thats what prompted me to investigate.
 
Tns said:
Surely this technology is on the obsolete side? i mean there is 3g/hspda and wifi/wimax? Al this sounds like there is more effort involved in getting it going that it's worth.
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Maybe, maybe not - coverage should be pretty good with BPL but then it may not be an issue if/when it finally becomes mainstream.
 
The problem with BPL is that most implementations are only a local loop technology, and a rather short one at that (few 100m).

I've been to one of Eskom's tests sites (part of Sunninghill) where all the houses in a road are connected to the local electrical distribution point (shed) via BPL. Guess what the backhaul from the shed is .... WiMAX ... kinda defeats the purpose.
 
Roman4604 said:
The problem with BPL is that most implementations are only a local loop technology, and a rather short one at that (few 100m).

I've been to one of Eskom's tests sites (part of Sunninghill) where all the houses in a road are connected to the local electrical distribution point (shed) via BPL. Guess what the backhaul from the shed is .... WiMAX ... kinda defeats the purpose.
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Telkodemonopolies' WiMax or is Eskom also running a WiMax trial network of its own? - I suppose it could also be MWeb WiMax.

BPL sounds like a total waste of time & effort.
 
ic said:
Telkodemonopolies' WiMax or is Eskom also running a WiMax trial network of its own? - I suppose it could also be MWeb WiMax.
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Internet Solutions ... before their license was pulled for being naughty.

The point I was making is, to sustain even realistic BPL performance in a wide-scale implementation, one has to build a large (amount of termination points) and deep (closeness to customer) fibre network. The fact that the last few 100m are carried over BPL is rather inconsequential in big picture.
 
ic said:
I do remember that TheRoDent briefly mentioned BPL and problems with the technology, maybe TheRoDent can explain in a bit more detail here...

EMR is a fact from existing power lines - any electrical current running through any piece of unshielded wire will produce some degree of EMR, my questions is, how far will that EMR radiate out and will the potential interference from broadband transmissions in previously unused frequency ranges through power lines not just be localised to the areas where the power lines run through.

I guess it depends on the frequency being used for broadband transmissions which will determine how far the interference travels...
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Existing EMR from power lines are in the range of ~100Hz. Don't know of any communication that uses that frequency or if it is even possible. The signals used for BPL can be hundreds or even thousands of different frequencies, the same as for ADSL, and apparently also what the Hams use. Interestingly more or less the same basic DSLAM architecture is used. Problem comes in that DSL uses twisted pairs where power lines are long and straight acting like giant antennas.

The interference isn't localised either. Since we are relatively out of the way of the rest of the world nobody will come knocking on our door if we use it. (Except the local Hams :p) In Zimbabwe though it would be a different matter as it could cut off communication between us and Japan. Imagine two people from two houses across each other sending signals using a torch. Now someone switches on a super bright spotlight right between their line of sight. Although both are still sending signals neither can see the other ones torch but only the spotlight.
bekdik said:
I don't believe that trying to bend a solution into an infrastructure not designed for it is ever a good idea. This kind of solution usually looks good in the short term, but solution designed technology usually surpasses it both in performance and cost effectiveness.

In the case of using power-lines for data transmission, fibre is a better solution and, with the more efficient ways of laying and producing fibre, is a better solution all round.
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DSL was never designed for the infrastructure they are using and neither was 14.4k modems. At some point it becomes necessary to reuse existing infrastructure with new technologies or we'll never see real progress, even in the rest of the world.
Roman4604 said:
The problem with BPL is that most implementations are only a local loop technology, and a rather short one at that (few 100m).

I've been to one of Eskom's tests sites (part of Sunninghill) where all the houses in a road are connected to the local electrical distribution point (shed) via BPL. Guess what the backhaul from the shed is .... WiMAX ... kinda defeats the purpose.
Click to expand...
Not really. WiMax is not what it is made out to be for multiple users but from fixed point to fixed point it is easier to optimise for maximum throughput. Other technologies like open air optical and microwave communication is also available. It would make sense to connect clusters of last mile networks together using these to a central point and only use fibre from there as the backhaul.
 
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Right on the button Hans. BPL, or any variation thereof should be rejected outright. To transmit HF signals on power lines would create havoc to all radio communications below 50 mhz. This includes military, broadcast, marine, ham etc etc. BPL or PLC is like a weed - allow it to grow, and it will fester and become difficult to remove. It must be stopped in the early stages.
 
If it should be stopped in its tracks then somebody should give us a proper alternative. Until then I hope research continues but unfortunately with another monopoly on it it's the same as the adsl situation we are in if it even arrives in your suburb.
 
At one time during the 80's it was said that copper wire couldn't carry more than around 56Kbps. Now we're seeing almost a 1000-fold increase in speed (obiovusly overseas, not in SA) over the very same wire because of a crafty group of researchers who wouldn't give up.

If one says that BPL is doomed because of something or something else, another group of expert researchers will find a solution and won't give up until it works better than 100%. When they reach their goal though, every single country in the world with a decent electricity supply system will be able to offer internet access to anyone who has electricity.. which is the vast majority of the people on earth. It just takes time, that's all, the kinks need to be ironed out, just like any other technology.

They said the photocopier was impossible as well.
 
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The problem is not that the power lines can't carry communications signals. Although there have been some questions about whether a real world electricity network can carry signals without excessive attenuation.

The problem is rather that the current alternative technologies are as effective or better. They don't cause damage to the RF environment and all the other restrictions that have been mentioned.

I don't have accurate figures but most of the current and not-too-distant-future wireless technologies have coverage and speed performances that are quite comparable to BPL if not better.

So why should research money be spent on technologies that have been shown to be problematic when better alternative solutions already exist?
 
MaD said:
At one time during the 80's it was said that copper wire couldn't carry more than around 56Kbps. Now we're seeing almost a 1000-fold increase in speed (obiovusly overseas, not in SA) over the very same wire because of a crafty group of researchers who wouldn't give up.

If one says that BPL is doomed because of something or something else, another group of expert researchers will find a solution and won't give up until it works better than 100%. When they reach their goal though, every single country in the world with a decent electricity supply system will be able to offer internet access to anyone who has electricity.. which is the vast majority of the people on earth. It just takes time, that's all, the kinks need to be ironed out, just like any other technology.

They said the photocopier was impossible as well.
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At one time during the 60's it was said that you can't communicate through the water supply and then a couple of kids went and took the quartz radio experiment a bit further and attached a wire to the ground and another wire to the tap, of course it only worked for a couple of meters with such a primitive setup. I was quite fascinated as a kid by books on the subject and thought why can't they use the electrical wiring to communicate. Apart from saying it can't be done the books were quite adament that the currents would actually kill you. Nontheless some did give the filters required for separating the electrical signal from the communications signal.

I guess the lesson we can learn from history is that all great advances come from amateurs seeking solutions to life's everyday problems and not from men in white labcoats. Telkom's local loop is more than 5km in a lot of instances. Multi-megabit adsl requires not more than ~1.5km. In contrast to this I can walk to the nearest electrical substation in 15 minutes. I would estimate that the average is a lot shorter than Telkom's. There is a way to stop interference with the radio spectrum. Contrary to what the hams believe and have been telling everyone it's not the technology that is causing it, if it was there wouldn't be adsl.
 
Prometheus said:
At one time during the 60's it was said that you can't communicate through the water supply and then a couple of kids went and took the quartz radio experiment a bit further and attached a wire to the ground and another wire to the tap, of course it only worked for a couple of meters with such a primitive setup. I was quite fascinated as a kid by books on the subject and thought why can't they use the electrical wiring to communicate. Apart from saying it can't be done the books were quite adament that the currents would actually kill you. Nontheless some did give the filters required for separating the electrical signal from the communications signal.

I guess the lesson we can learn from history is that all great advances come from amateurs seeking solutions to life's everyday problems and not from men in white labcoats. Telkom's local loop is more than 5km in a lot of instances. Multi-megabit adsl requires not more than ~1.5km. In contrast to this I can walk to the nearest electrical substation in 15 minutes. I would estimate that the average is a lot shorter than Telkom's. There is a way to stop interference with the radio spectrum. Contrary to what the hams believe and have been telling everyone it's not the technology that is causing it, if it was there wouldn't be adsl.
Click to expand...

This is like a blo*dy Game being played that I don't understand... I just know that you are getting warmer... :D
 
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