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BT offers London-wide Ethernet LANs

BT is gearing up for its 21st Century Network with a service that lets firms extend their office network within the M25

BT will offer Ethernet networks that span London, in a new virtual private LAN service (VPLS) that forms a stepping stone to its much-heralded 21st Century Network.

"It’s for anyone with five or six sites in the London area that wants to disseminate information between them," said Alan Davis, worldwide head of BT Internet Services. "We believe this is the first launch of a city-wide VPLS uncontended network."

The Ethernet Virtual LAN (EVLAN) service extends BT's existing LAN/SAN extension service, which uses fibre connections to make Ethernet links between places up to 25km apart and is currently being rolled out to all London schools in a Government-backed project.

EVLAN increases the distance, and the number of connections possible, by linking sites through six major BT points of presence (POPs). This will allow BT to offer 10Mbps, 100Mbps or 1Gbps of uncontended LAN bandwidth between any two points, essentially extending anyone's LAN to anywhere within the M25. "It’s dedicated Ethernet," said Davis. "The POPs are held together by native, Layer 2, dedicated Ethernet."

The price is undetermined as yet, but Davis said it was likely to be close to the current price of LAN/SAN, so a 10Mbps link might cost £10,000 to install, and then upwards of £5,000 a year in rental. "We can do a lower connection cost and higher rental," said Davis. "We are trying to match with the LAN /SAN portfolio." Companies who need connections installed further away from the POPs will pay a higher price to have fibre laid to their offices.

The service will be "21CN-ready", as it uses the same Alcatel switches that will be used in BT's 21st Century Network (21CN), an all-IP backbone which will be rolled out over the next few years.

Although only available in London now, EVLAN could be extended to another five cities once 21CN is built. "Two of the POPs are co-located with MPLS POPs on the 21CN," he said. "If we needed to, we could hold metropolitan areas together with MPLS in the 21CN."

The service can also be extended to greater speeds, as optical techniques can run multiple channels on the fibres used, through dense wavelength digital multplexing, which sends signals on different colours.