BT's 21CN (21st Century Network) is a radical and almost total overhaul of the present BT network infrastructure.

To quote Wikipedia, "It will see the UK incumbent's telephone network move from the present AXE/System X Public Switched Telephone Network (PSTN) to an Internet Protocol (IP) system".

In fact, the Wikipedia article gives a fairly decent overview of the technical specs for the project, but BT has been rather more cagey about tangible products that will be available once the overhaul has finally completed - it started in November 2006 and is likely to continue into 2012.

The major product that we do know will affect the UK broadband market is Wholesale Broadband Connect (WBC). The major contributing factor towards WBC is the upgrading of equipment at exchange level and "Node" level to accommodate ADSL2+ broadband over copper telephone lines..

Now, it should be noted that the introduction of MSAN (Multi Service Access Node) technology has actually been around and in use for some time. Indeed, Fusion's partners at Cable & Wireless have ensured all their 800+ exchanges in the UK have been MSAN-compatible for several years, allowing high speed ADSL2+ access well in advance of BT's new products.
Fusion's own B2B+ service was built upon C&W's Next Generation Network platform.
So, whilst not exactly brand new technology, the most exciting end result of WBC is that it will bring ADSL2+ access to virtually the whole of the UK over the next three years.

Well, eventually, the "up to 8Mb" Max services will cease to exist, to be replaced by "up to 24Mb" ADSL2+.

The "standard" and "premium" variants will still carry forward, although the difference will be less on defined contention ratios, and more on higher traffic prioritisation.

Initially, BT are making no provision for the Annex M variant, which allows for a higher upstream rate, however the general industry expectation is that this will follow as an enhancement eventually.

However, Fusion plans to launch Annex M ADSL2+ with Cable & Wireless at the end of 2009.
Following evaluations, Fusion's full commitment to WBC will commence in Autumn 2009, where we will start to regrade all existing Max customers to ADSL2+ where the service has already become available. 2010 is the real focus for exchanges upgrading, and Fusion will be upgrading clients as soon as their local exchange is lit through the year.

Crucial for businesses will be where the initial products MAY develop following launch. Fusion's 1:1 contention Vita DSL service was built upon a Max Premium tail circuit and was considered an innovative advance using the existing technology. We are already testing options for enhancing 21CN products for the business market, and will of course provide updates as these become available.

BT's 21CN - What about current low contention services? VitaDSL, SDSL and Ethernet?

Headline speeds for ADSL2+ products are very attractive for buyers, particularly small businesses and home users, but the services are still no replacement for low contention, premium broadband.

There are no plans to remove Vita and SDSL from the Fusion product portfolio - indeed, "legacy" products such as these are expected to remain viable for at least a further 4-5 years.

What will be expected to slowly take over from current premium services is 1:1 contention ethernet. Prices for ethernet are now far more competitive than even 12 months ago, and the case for purchasing ethernet instead of copper based DSL for high-end services is becoming increasingly compelling.

Fusion is at the forefront of delivering highly cost effective ethernet solutions, and our commitment to this continues as we look at brining even further value to these services in the next 12 months.