CIENA Captures Bell Atlantic DWDM Business; Expands Into Local Exchange Carrier Market.

LINTHICUM, Md.--(BUSINESS WIRE)--March 30, 1998--CIENA Corporation (NASDAQ: CIEN) announced today that it has reached an agreement to supply Bell Atlantic with CIENA's dense wavelength division multiplexing (DWDM) optical transmission systems. Under terms of the agreement, CIENA has been initially allocated 50% of Bell Atlantic's DWDM purchases over the next five years. General deployment is expected in the second half of 1998, subject to completion of ongoing testing. CIENA's DWDM systems are the only DWDM systems to have completed laboratory evaluation at Bell Atlantic.

"CIENA's optical transport products will help Bell Atlantic to stay ahead of the demand for more bandwidth being generated by the increasing growth of data and internet services," said Paul Lacouture, chief technology and engineering officer, Bell Atlantic.

Bell Atlantic's DWDM deployments will mark the first time a local exchange carrier (LEC) has committed to deployment of the technology. "This is one of the steps in Bell Atlantic's plans for an all-optical network," Lacouture said.

"The deployment of CIENA's MultiWave Firefly(tm) and MultiWave(R) 1600 in local exchange carrier networks is the next logical step for CIENA's optical transmission products," said Patrick Nettles, CIENA's president and chief executive officer. "The economics and scaleability of CIENA's DWDM equipment will enable local exchange carriers like Bell Atlantic to deploy a leading-edge technology that should handle all of their customers' bandwidth demands for the foreseeable future."

"By winning this account, we've completed the first in a series of milestones we set for ourselves when we started building our sales and support infrastructure for the LEC market over twelve months ago," stated Larry Huang, CIENA's senior vice president of sales and marketing. "CIENA's industry-leading technology and unparalleled experience in deploying DWDM networks should provide Bell Atlantic with some of the critical elements it will need to deploy its next generation broadband data network."

The supply agreement between CIENA and Bell Atlantic has no minimum purchase commitments and includes CIENA's long-haul systems (MultiWave(R) 1600 and MultiWave Sentry(tm)), its short-haul systems (MultiWave Firefly(tm)) as well as its network management solutions (WaveWatcher(R)).

CIENA's leadership in DWDM and optical networking has been demonstrated by the widespread acceptance and deployment of the MultiWave(R) 1600 and MultiWave Sentry(tm) in the inter-exchange carrier market in the U.S. as well as in Europe and Asia. Entry into the local exchange carrier market with products like the MultiWave Firefly(tm) further strengthens CIENA's position as the optical networking leader.

NOTE TO INVESTORS

Forward-looking statements in this release, including statements regarding the expected timing of general deployment of CIENA's equipment in the Bell Atlantic network during the second half of 1998, subject to completion of ongoing testing is 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 by such forward-looking statements, due to risks and uncertainties associated with the Company's dependence on its major customers and their spending patterns, including specifically the impact on the Company's near term operating results of WorldCom's recently announced change in purchasing practices, the challenge of transitioning to the manufacture of multiple product lines in fiscal 1998, and the overall management of its expansion. The forward-looking statements should be considered in the context of these and other risk factors disclosed in the Company's Form 10-Q, filed with the Securities and Exchange Commission on February 19, 1998.

ABOUT CIENA

Based in Linthicum, Maryland, CIENA Corporation is a worldwide market leader of open architecture, dense wavelength division multiplexing (DWDM) systems for long-distance and local exchange carriers. CIENA's DWDM solutions include the MultiWave(R) 1600 and 4000 long-haul transport systems, WaveWatcher(R) network management software, the MultiWave Optical Add/Drop Multiplexer, the MultiWave Sentry(tm) enhanced long-distance transport system and the new MultiWave Firefly(tm) and MultiWave Metro(tm) short-haul systems. Through its Alta subsidiary, based in Norcross, GA, CIENA provides a range of engineering, furnishing and installation (EF&I) services for telecommunications service providers in the areas of transport, switching and wireless communications.

CIENA's DWDM equipment expands the carrying capacity of fiber optic networks by dividing the optical signal into several separate optical channels or wavelengths. An optical fiber without DWDM technology carries a single color of laser light, or a single wavelength, on which travels approximately 32,000 voice or data transmissions. CIENA's DWDM technology divides the single wavelength into multiple colors, or channels, thereby multiplying the capacity of the fiber by the number of channels and enabling service providers to expand bandwidth without the expensive process of adding more fibers. -0- Additional information about CIENA can be found on its World Wide Website: http://www.ciena.com.

CONTACT: Press Contact:

Denny Bilter

CIENA Corporation

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Ells Edwards

Bell Atlantic

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Investor Contact:

Suzanne DuLong

CIENA Corporation

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