[LINK] Power lines offer broadband alternative

[Chirgwin, Richard]

Ahem. 45M >bytes< per second? "45 megabytes a second, rivalling some DSL
services." Reckon some linkers would love to know where you can get DSL
services that are "rivalled" by 45 megabytes per second ... who can get 340M
bps on DSL?

Still, I think having the review is a good idea, even if only to do some
hype debunking.

An error of confusion in the article:
> PLC, which operates across the power lines themselves. 
> Users access
> PLC through a specialised modem that connects to a power point.

Two different technologies lumped together here: powerline in the home (for
eg look at homeplug.org) and powerline for a "last mile".

I could get a bunch of Linksys powerline modems, and use the in-home
powerlines to redistribute signals from an ordinary modem or an ADSL modem
or a cable TV router.

In the other direction, a utility could terminate a powerline last-mile
service to a box with an Ethernet outlet. Which is quite likely, because
in-home is a very unpredictable signal environment (an article in CommsWorld
last year covered this. IIRC, an in-home electrical cable may drag speeds
down to the hundreds of kilobytes - that's a damn slow LAN).

The "powerline end-to-end" vision is actually product pitch from various
vendors (for eg Main.net).

It's not all hype, however. Scottish Hydro is running a broadband powerline
service.

Remember, though, that it's a shared service. From the head end, you get 45M
bits/s to however many households are served - so our old friend
oversubscription will rear its head. I'm not at all sure how privacy is
preserved (remembering that we have to ensure that users can't sniff each
others' private traffic; AND that a freelance hacker can't sniff traffic by
capturing radio emissions from those lovely long antennas from the house to
the transformer).

Final observations: standards in powerline are, as far as I'm aware, in
short supply. In-home is slightly better with HomePlug pushing for
standards. But their standards are for 10M bits/s, not 45 somethings.

Richard Chirgwin

> -----Original Message-----
> From: Bernard Robertson-Dunn [mailto:brd at austarmetro.com.au]
> Sent: Thursday, 3 April 2003 13:19
> To: Link
> Subject: [LINK] Power lines offer broadband alternative
> 
> 
> <brd>
> A topic we have discussed on Link several times over the past six or
> seven years.
> </brd>
> 
> Power lines offer broadband alternative
> Apr 3
> Ben Woodhead
> Fin Review
> http://afr.com/it/2003/04/03/FFX97V370ED.html
> 
> The federal government has launched a review of controversial 
> technology
> that would allow the use of power lines to deliver high-speed 
> internet and
> data services to homes.
> 
> Known as power line communications, or PLC, the technology 
> could transform
> common power lines into high-speed communications links with 
> the potential
> to resolve many of Australia's "last mile" broadband access issues.
> 
> The review, managed by the Department of Communications, IT 
> and the Arts,
> is one of two broadband research projects announced by the 
> office recently.
> 
> As reported by The Australian Financial Review last Tuesday, 
> DCITA has also
> launched a review of the nation's high-bandwidth transmission
> infrastructure to determine the volume of unused capacity owned by
> telecommunications operators and other organisations such as 
> rail operators
> and electricity distributors.
> 
> Much of that review is to focus on dark fibre, the optical 
> cable that has
> been laid but remains unused. Many rail operators and electricity
> distributors own high-capacity fibre optic networks. These 
> are distinct
> from PLC, which operates across the power lines themselves. 
> Users access
> PLC through a specialised modem that connects to a power point.
> 
> "As electricity distribution networks access more residences 
> than either
> cable or even telephone lines, Australia's electricity 
> distribution network
> could be used to provide an alternative telecommunications 
> network," DCITA
> said in a tender calling for consultants to conduct the PLC review.
> 
> "The development of PLC technologies may offer communication providers
> another option for the provision of communications services 
> to end-users in
> rural and remote Australia." The review will assess the 
> viability of PLC,
> which some claim is capable of data transmission rates of up to 45
> megabytes a second, rivalling some DSL services.
> 
> PLC is still in the early stages of development though and 
> many questions
> hang over its ability to deliver quality services to homes.
> 
> The DCITA tender asks applicants to assess technical 
> impediments to the
> implementation of PLC as well as potential service levels, 
> including data
> rates.
> 
> "While the fundamentals of electricity distribution a re 
> essentially the
> same in every country, there is a considerable variation in 
> reticulation
> standards and wiring practices from network to network," 
> DCITA said in the
> tender documents.
> 
> "These differences impact on the ability to implement 
> feasible PLC systems
> and may necessitate a variety of implementation strategies." Despite
> reservations, governments and utilities around the world are 
> exploring PLC
> as a means of boosting broadband penetration.
> 
> In other broadband developments, telecommunications journal 
> Communications
> Day reported that broadcast transmission provider Broadcast 
> Australia was
> trialling the delivery of broadband over datacasting spectrum 
> in a further
> bid to push high-speed internet access to rural and regional 
> Australia.
> 
> -- 
> We believe that electricity exists, because the electric company keeps
> sending us bills for it, but we cannot figure out how it 
> travels inside
> wires.
> -- Dave Barry
> 
> Regards
> brd
> 
> Bernard Robertson-Dunn
> Canberra Australia
> brd at austarmetro.com.au
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