France Telecom showcases VDSL2 broadband

By Matt Whipp

Posted on 8 Sep 2005 at 13:09

France Telecom, parent of UK subsidiaries Wanadoo and Orange, has demonstrated VDSL2 broadband technology at its headquarters in Issy-les-Moulineaux in Paris.

VDSL2 uses an extended frequency range of 30MHz and DMT modulation to massively expand the bandwidth available to as high as 100Mbps, still using standard 'last-mile' copper connections.

In the test, the company placed increasing loads on the service. Starting with two HDTV signals, the demand was initially 25Mbps - far above the 18Mbps ADSL2+ services that are starting to roll out in the UK. On top of this, a high-definition video camera added a 2Mbps live stream, a digital TV signal added another 4Mbps, and FTP file transfers took the total load to more than 80Mbps.

Jea-Yves Leonnec, Director of Middleware and Advanced Platforms at France Telecom's R&D facility said that first deployments could begin in 12 months' time, although this will initially start with urban centres and specific corporate premises where it is possible to place the DSLAM as close as possible to the users.

VSDL2 deteriorates quickly from a theoretical maximum of 250Mbps at 'source' to 100Mbps at 0.5km, but degrades at a much slower rate from there, and still outperforms VDSL1.

France Telecom has already invested in technology to reduce the demand on the ATM (Asynchronous Transfer Mode) hardware and to ensure performance levels on VDSL2 connections where they are deployed alongside other systems in the local loop.

Leonnec said that such high bandwidths will be vital to supporting services such as videoconferencing and content broadcast and shared over IP networks. As such, VDSL2 is a symmetric technology with the same upstream and downstream bandwidths. He said that 'we'll see more and more peer-to-peer architecture as content is managed from or on devices, rather than on the network.'

BT is also pursuing this approach, as we saw when Kevin Foster, Manager of BT's Advanced Copper Technologies Unit, guided us around an idealistic, gadget-laden Broadband Home in the Adastral Park research centre.

Indeed, VDSL2 is still very much in its infancy. The recommendation for the standard was only finalised in May and comments that followed are still being resolved.