Internet Through Power Lines in SA?!

[Karnaugh]

Just like to stomp some wrong information and inform people a bit better before I read another line of text about how "1337 PLC wlil chenge our lifes !!"

Firstly PLC stands for Programmable Logic Controller.

Power Line Carrier Communication is <b>PLCC</b> (I distrust anyone who cant get that right and claims they are in the business of providing it! Although the typo seems easy)

PLCC will not revolutionize the internet, it will not become a major carrier for internet. Firstly one major problem is that power cables have very high attenuation at high frequencies. I doubt you'd reliably get anything over 10Mbps. As things stand other technologies have much more potential as far as bandwidth goes (Wireless for one). If one got 10Mbps through a power grid, remember its SHARED as PLCC has to operate in a buss topology (since wires are generally a common phase unless each plug had its own phase, in which case you're much better off with CAT5 for the cost of that and we are back to square one)

Cost is the other factor. While you may thing "wow but there is already a huge power grid that we can utilize!" one needs to actually realize how it operates (and very often doesn’t operate since its run by the municipality). Throughout the grid power is being stepped up and stepped down through transformers that are designed for 50Hz operation. The chances of you getting a signal further than your street is unlikely, and if it were it would be horribly attenuated and distorted. The signal certainly wouldn’t travel through a transformer. One could place a repeater to relay signals around transformers, but the cost in doing that for what you get at the end of the day questions its viability and potential verses Wireless or even CAT5/CAT6.

So with that in mind, PLCC is useless IMHO, it will never be what people think it is, there are fundamental limitations and the cost to overcome those really don’t make it any more feasible than much better technologies out there.

Another myth is that Eskom use PLCC, they DONT! They run optical fiber in the center of their power cables.

- Colin Alston
colin at alston dot za dot org

"Getting traffic shaping right is easy and can be summed up in one word: Dont." -- George Barnett

 

[donn]

The problem with this technology is that you lose all the data whenever a transformer is in the way. Eskom has been using this facility for years to talk on the phone down their HT wires. But if you try to listen in at home you won't hear anything because the transformers can't transform these frequencies when they convert high voltage down to 220V.

There are plenty of other applications (intercoms, etc) that can use normal power lines.

Donn Edwards
http://privacy.4mg.com

 

[mbs]

Probably going off at a tangent here, but I think Eskom would be far better off focussing on ensuring a sustainable power resource for the future - I read somewhere that we're going to have problems circa 2007. They should withdraw entirely from the SNO, or at most become a facilitating partner for the utilisation of PLCC technologies (hehe - note: I got the acronym right!). I wonder if they are in fact actively involved in the research and development of this, perhaps with the CSIR or private industry?

 

[Karnaugh]

I think we missed the point that Eskom have little intrest in PLCC, they use Fibre optics which has a far greater bandwidth (10 TBps or something is the largest speed attianed and there is room for more).

Eskom are not trying to partake in the SNO, they simply are leasing out their vast network to the SNO as a backbone and taking a share in the profits.

- Colin Alston
colin at alston dot za dot org

"Getting traffic shaping right is easy and can be summed up in one word: Dont." -- George Barnett

 

[mbs]

Ah, I see... thanx for the heads-up, KARNAUGH...