CIENA Launches Operations in Brazil; Optical Networking Leader Furthers Presence in Latin America Market By Opening CIENA Brazil Limitada in Sao Paulo.

Business Editors/Hi-Tech Writers

RIO DE JANEIRO, Brazil--(BUSINESS WIRE)--April 10, 2000

CIENA Corporation (Nasdaq: CIEN) today announced at Telecom Americas 2000 that it has opened CIENA Brazil Limitada, a wholly owned subsidary of CIENA, in Sao Paulo, Brazil.

Staffed by local engineers and managers, CIENA's operations in Brazil will deliver the company's market-leading intelligent optical networking solutions to meet the demands of one of the world's fastest-growing telecommunications markets.

CIENA pioneered the commercial development of intelligent optical transport technology called dense wavelength division multiplexing (DWDM) and, in the process, helped change the economics of bandwidth. Today, CIENA provides complete optical networking solutions for service providers around the globe.

Experts predict the $18-billion (USD) Brazilian telecommunications market will explode to $45 billion by 2003,(1) with data services expected to grow by 300 percent.(2) As a result, service providers throughout Latin America are aggressively introducing new services and investing in network infrastructure to meet this demand.

"As Brazil's telecommunications industry continues to expand, CIENA is now well positioned to support the growth of this exciting marketplace," said M. Arely Castellon, CIENA's vice president, Latin America. "We are moving forward to provide intelligent bandwidth and network management solutions for the continued success of Latin America's leading carriers and ISPs."

With CIENA LightWorks(TM), a complete blueprint for implementing next-generation optical networks, the region's rapidly growing carriers will be able to efficiently scale networks to meet demand, dramatically simplify their legacy networks, and more easily deliver additional broadband services at lower costs.

This architecture extends integrated capabilities in optical transport, core switching, automated provisioning, flexible restoration, and multi-service access through software-driven intelligence embedded throughout the optical network. These solutions scale to meet the networking needs of Brazil's new entrants as well as global network providers.

CIENA's recently announced LightWorks Toolkit(TM) provides service-enabling technologies such as Wavelength Binding(TM), VSR Optics, Flexible Concatenation(TM), Transparent Service Multiplexing(TM) and Optical Priority Provisioning(TM).

Carriers will be able use these innovative technologies to quickly bring differentiable new optical services to market, including automatic bandwidth bursting, optical virtual private networking, and dynamically prioritized services to meet service level agreements.

CIENA named Carlos Pinto Jr. sales manager for the new Sao Paulo office. Carlos has comprehensive experience in the telecommunications industry, including serving as country manager for Brazil at a multi-service wide area networking company.

Marcos Cesar Frutos da Silva leads systems engineering in Brazil. He has extensive experience in optical networking and previously worked for a major telecommunications equipment developer in Brazil.

CIENA Brazil is located at Centro Empresarial Nacoes Unidas, Torre Oeste, Av. das Nacoes Unidas, 12.901, CEP 04578-900, Sao Paulo. Phone: [phone]. Fax: [phone].

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(TM) 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.

NOTE TO INVESTORS

Forward-looking statements in this release, including, but not limited to, the size and growth of the Brazilian telecommunications market, cost savings, deployment timing and network management benefits of the Company's products, including LightWorks Toolkit, are based on information available to the Company as of the date hereof.

The Company's actual results could differ materially from those stated or implied in such forward-looking statements, due to risks and uncertainties associated with the Company's business, which include the risk factors disclosed in the Company's Report on Form 10-Q filed with the Securities and Exchange Commission on February 17, 2000.

(1) Source: Dataquest's Brazilian Telecommunications Market

Analysis, 1999

(2) Source: Dataquest's Preliminary Latin American Telecom

Services Forecast, 1999