CIENA ANNOUNCES DISMISSAL OF CLASS ACTION COMPLAINT

Linthicum, MD — 05/17/2000

Ciena Corporation (CIEN) today announced that United States District Court for the District of Maryland has dismissed the consolidated securities class action complaint naming Ciena and certain of its officers and directors as defendants.

The complaint, originally filed on August 26, 1998 and subsequently dismissed and re-filed on August 20, 1999, alleged that Ciena and certain of its officers and directors violated certain provisions of the federal securities laws by making false statements, failing to disclose material information and taking other actions to artificially inflate and maintain the market price of Ciena's common stock during the Class period of May 21, 1998 to September 14, 1998. Ciena's motion to dismiss the second amended complaint was granted and the action was dismissed by the order of the Honorable J. Frederick Motz, United States District Judge for the District of Maryland.

Once a judgment is entered, the order will be subject to appeal. The Company has no information as to whether an appeal will be taken.

"We're pleased with the ruling. We are happy to put the distractions of this litigation behind us so that we can continue to focus on building shareholder value," said Patrick Nettles, Ciena's president and chief executive officer.


About Ciena

Ciena Corporation's market-leading optical networking systems form the core for the new era of networks and services worldwide. Ciena's LightWorks™ architecture enables next-generation optical services and changes the fundamental economics of service-provider networks by simplifying the network and reducing the cost to operate it. Additional information about Ciena can be found at http://www.ciena.com.
Press Contacts:
Nicole Anderson
Ciena Corporation
(877) 857 -7377
pr@ciena.com
Investor Contacts:
Marie Downing
Ciena Corporation
(888) 243-6223
ir@ciena.com