BT CHOOSES CIENA AS A STRATEGIC PARTNER FOR ITS NEXT-GENERATION NETWORK

CIENA’s End-to-End Optical Portfolio to Form Foundation For Global Operator’s Next-Generation Network

Linthicum, MD — 05/01/2003 Ciena® Corporation (NASDAQ: CIEN), a leading provider of intelligent optical networking systems and software, today announced that BT plc has selected Ciena’s LightWorks™ solutions portfolio as part of its new, next-generation network. The global three-year deal will place Ciena in the role of a strategic supplier of optical transport and switching equipment and network management software. Initial deployments are expected by the end of Ciena’s fiscal 2003.

The global contract specifies that BT Group, including BT Wholesale, BT Retail and BT Global Services, will have the ability to purchase Ciena’s portfolio of products to enable greater automation of network operations, and faster provisioning of services for BT, thereby allowing BT to more efficiently deliver services to its global customer base. In addition, Ciena will provide the associated installation, support and services that have been customized to meet the aggressive timeline and specifications that BT requires.

The distributed intelligence throughout Ciena’s product-line, exemplified by Ciena’s LightWorks OS™ Network Operating Software, will provide the automated and scalable infrastructure BT needs to serve new and existing customers, without the high operational costs traditionally associated with managing a static, manual infrastructure. By taking advantage of a “mesh-based” network core, BT will increase survivability for its core services.

“We look forward to partnering with BT, and are pleased that BT, one of the premier incumbent carriers in the world, has recognized the value our LightWorks architecture brings, as the company focuses on providing broadband data services to its customers,” said Gary Smith, president and chief executive officer of Ciena. “We are delighted to be able to fully support BT’s aim of creating a simpler, more efficient and more intelligent carrier-class network .”

Products that BT has included in the three-year global contract include Ciena’s CoreDirector®, CoreStream™, ONLINE Metro™, ONLINE Edge™ and MetroDirector K2™. Also, Ciena’s ON-Center® Management system combines element, network and service management capabilities, along with simple point-and-click provisioning, and robust, carrier-class scalability and reliability, to help BT manage its network efficiently.