RESEARCH TRIANGLE PARK, N.C. — Cingular has signed a three-year contract with Nortel for services and equipment as part of its wireless network upgrade plans.

Cingular is in the process of updating its network to support more 3G multimedia applications.

Terms of the deal were not disclosed.

Both companies said the Nortel deal would help Cingular "reduce costs, increase network reliability and improve the quality of service for subscribers through the use of a more cost efficient, packet- switched core network."

"This contract represents a new footprint for Nortel and is a testament to our leadership in voice over packet technology and 3G wireless broadband solutions," said Mike Zafirovski, president and chief executive officer of Nortel, in a statement. "We're applying our networking expertise from wireless and wireline packet voice technology to help make operators like Cingular more successful."