[UK - TheReg] BT to stretch DSL to absolute limit

bk

BT to stretch DSL to absolute limit

At the moment DSL in the UK reaches people at up to 6km from the exchange. They are now running trials to see if it will reach up to 10km.

I believe in Ireland, Eircoms DSL reaches only 3km from the exchange, what a joke.

Urban Weigl

Yep, read that on The Register today. It also mentions that they the service at 10km will be the full 512/256 product, and that they will even do testing beyond 10km to see how well that works.

watty

NEC now sells Telcos a VHDSL product that alows ISDN at same time.. 20Mbit at up to 10K.

In a year or so to install and run this on local loop will be same as existing gear.

thegills

Fair play to BT for being innovative and actually wanting people to buy DSL. Why can't BT Ireland follow suit??

Milton Keynes is the most boring place in the UK.

thegills

Urban Weigl

Originally posted by thegills
Fair play to BT for being innovative and actually wanting people to buy DSL. Why can't BT Ireland follow suit??

They would if ComReg allowed proper unbundling. Right now with the fee structure here, it just isn't possible to do this (believe me I know).

Tenshot

I'll be well impressed if they can get much over 5 Km; I was involved in some DSL lab testing a few years ago, and that was pretty much the cut-off point for a range of different DSL equipment. (This was in ideal conditions as well - introducing cross-talk etc. dropped that down to below 4 Km).

Still, nice to see they're willing to give it a try...

watty

Probabily not "traditional" BB/ADSL gear. It will be the newer kind of stuff. Different carrier / modulation method.

You'll still need to get rid of any loading coils in the circuit, i'd imagine.

Urban Weigl

To say that DSL technology has progressed a lot in recent years is almost an understatement. BT have already been testing lines as OK up to about 6km from the exchange for some time, and 5.5km before that. T-Online in Germany are also quoting 6km as the distance they will do installs at currently.

What I will actually be interested in is what speeds they will get at over 10km, since the article only mentions full 512k service at up to 10km. I don't think they'd try if they had not already run their own tests that showed it should work (note the usage of the word should).

watty

The new product, "VDSL concentrator VC1200" and "VDSL modem VF100T/100TD" is the newest addition of NEC's access systems solutions realizing industry-fastest 51.2 Mbps access speed. The new products supports a full range of VDSL and Ethernet technologies in an architecture that allows for easy migration from narrow-band to broadband services and can be economically expanded to meet customer demand.

And this was TWO YEARS ago.


More at http://www.nec.co.jp/press/en/0203/1202.html

And
http://www.findarticles.com/cf_dls/m0IUL/8_36/90794499/p1/article.jhtml

also
http://www.unisys.com/communications/insights/white__papers/papers.htm?insightsID=8681

The basic ADSL variant has a maximum transmission span of up to 10 km. The maximum transmission distance possible over copper pair decreases as the maximum bit rate gets higher.

For the highest speed VDSL, the maximum distance is about 300 m. A decrease in the operating bit rate for any of the variants increases the maximum transmission distance, so VDSL operating at up to 8 Mbits/s has a maximum span of about 3 km.

Up to 4.6Mbps at nearly 7km for xDSL seems fairly standard. So at 10Km I'd assume something between 1Mbit and 4.6Mbit is fairly possible now.

watty

This
http://www.nextgendc.com/?/seminar_xdsl.htm
is a good intro to how DSL works. Normal DSL does not allow ISDN.
The VDSL and some other xDSL varients do allow ISDN.

Or this
http://www.pcquest.com/content/broadband/101030103.asp

Johnny_the_fox

already in the North a BT exchange covers a 5 miles radius... ( or 8.04672 km radius)