Sainsbury's has completed the installation of a major new network across 463 of its stores, which supplier BT claims is the largest Multiprotocol Label Switching (MPLS) network in the UK.
The roll-out is part of Accenture's ongoing outsourcing contract to modernise the supermarket chain's IT infrastructure.
The MPLS network, which BT said is also one of the largest in Europe, will allow peer-to-peer communication between stores.
Sainsbury's began the modernisation programme in late 2000, when it signed a deal to outsource the design, building, implementation and running of its IT systems and networks to Accenture.
As part of the deal, 800 staff transferred from Sainsbury's to Accenture.
At the time of the deal, the supermarket wanted to reduce its £200m-a-year IT bill while at the same time improving business efficiency. It felt that its ageing systems were hampering its ability to compete and would not handle the company's e-commerce requirements.
BT also expects to finalise a major 10-year, £1.5bn outsourcing contract with the Royal Mail any day now, as part of the Computer Sciences-led Prism Alliance. BT estimates its share of the contract to be worth £450m.
Once signed, the Prism Alliance - which also includes Xansa - will provide a range of IT services, including the maintenance of 42,000 desktop computers and the management and development of the Royal Mail's server, mainframe and network infrastructure.
Around 2,000 people, mostly IT staff, will be transferred to the Alliance under the deal.
The Royal Mail would not comment on the deal, but a spokeswoman said: "The contract has not been signed and negotiations are still continuing."
The contracts are the latest in a raft of outsourcing deals that BT has signed in the past six months. The deals include contracts worth ? ¬1bn, £125m and £140m with Unilever, Abbey National and Bradford & Bingley respectively.
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