BT Global Services has struck a deal with Barclays to provide an IP network worth £500m over a seven-year period.
The contract, negotiated by consultant Xantus, covers IP WAN and LAN, as well as voice services.
"When people sign long-term deals they want to know that the options will be there in the long term," said Steve Watmough, managing director of Xantus.
"This is a complex deal. We're not changing the technology on day one but, in the future, when some products hit a certain price point, they can make the move."
Analysts at Ovum Holway pointed to BT's early lead in providing managed voice over IP (VoIP) services to large financial businesses in the UK, but also cited a contract with Lloyds TSB that the carrier lost to IBM last year.
Sources in the industry have said that BT is now thinking of voice as one feature that sits on top of a delivery network rather than thinking of voice as the be-all and end-all. All telcos are facing up to shrinking call margins and increased competition.
"This deal is related to 21CN [BT's plan for a nationwide IP infrastructure] in that once we have built an entire BT network, VoIP becomes far more attractive and cost-effective for everyone," said a BT representative.
However, as far as is known, Barclays is not using the network for VoIP services just yet.
BT expects Barclays to make efficiency savings of more than 30 per cent over the life of the deal.
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