Atlantic Telephone Becomes Newest Customer for CIENA's Next-Generation Broadband Loop Carrier.

LINTHICUM, Md. -- CIENA's CN 1000 Reduces Total Cost of Ownership for Atlantic and Paves the Way for Delivery of Advanced Services

CIENA(R) Corporation (Nasdaq:CIEN), a leading global provider of intelligent service creation and delivery solutions, today announced that Atlantic Telephone has deployed its CN 1000(TM) Next-Generation Broadband Access Platform, illustrating the latest addition to CIENA's list of successes in the broadband access market.

Atlantic Telephone Membership Corporation is the largest member-owned telephone cooperative in North Carolina, with more than 33,000 members and 43,000 access lines, several of which are now served by CIENA's CN 1000 Broadband Loop Carrier (BLC) platform. Because the CN 1000 provides plain old telephone service (POTS) and asynchronous digital subscriber line (ADSL) service on every line, Atlantic Telephone can software-provision broadband service to any subscriber as orders are received, dramatically reducing operational costs and accelerating time-to-revenue.

"We required a next-generation BLC that would not only reduce our total cost of ownership, but also increase our port density and our ability to offer advanced services from a single platform," said Larry Clemmons, vice president of network and plant operations at Atlantic Telephone. "With CIENA's CN 1000, we're able to rapidly deploy DSL and expand our capability to add high-value voice, data and even video services down the line."

According to Clemmons, Atlantic Telephone evaluated a number of remote switch, Digital Loop Carrier (DLC) and BLC offerings before selecting the CN 1000. Clemmons said the CIENA platform offers "much higher port density with comparable features, at a much more competitive price." Additionally, Atlantic expects to reap considerable long-term benefits with the CN 1000 as it continues to expand its voice and data services portfolio.

"Atlantic Telephone was looking to invest in a solution that would not only enable them to immediately offer DSL to its customers, but also one that offered a wide array of upgrade options and features for future service deployments," said Jim Hjartarson, senior vice president and general manager of CIENA's Broadband Access Group. "The CN 1000 is a natural fit for carriers seeking a cost-effective way to deliver these types of services and efficiently plan for network upgrades to support advanced services such as VoIP and IPTV."

About CIENA's CN 1000 BLC Broadband Access Platform

The CN 1000 Broadband Loop Carrier is a high-density broadband access system that delivers integrated voice, data and video services at a fraction of the cost of competing systems. The CN 1000 provides POTS, DSL and Packet Voice capability on every line, enabling carriers to software-provision these services to any subscriber - remotely, without manual intervention. By integrating the functions of a next-generation DLC (NGDLC), a video-enabled digital subscriber line access multiplexer (DSLAM), a fiber multiplexer and a packet-ready media gateway, the CN 1000 greatly simplifies the access network.

The CN 1000's unique POTS+DSL architecture offers the service provider two significant cost advantages over competing systems:

--"Right-to-Use" DSL - The remote-provisioning capability of the CN 1000 allows CIENA to offer the platform to carrier customers on a "right-to-use" (RTU) basis, under which the service provider pays CIENA only when a port is turned up, rather than when the line card is first installed. This pay-as-you-go approach dramatically reduces initial CapEx costs.

--DSL Portability - Once a DSL right-to-use port has been purchased, it can be turned up, and moved at any time, anywhere in the network. If a customer cancels the service, that DSL port can be turned up at another location, without the need to purchase another RTU license. This portability eliminates the traditional high cost of churn associated with DSL service.

ABOUT CIENA

CIENA Corporation delivers innovative network solutions to the world's largest service providers, cable operators and enterprises, increasing the cost-efficiency of current services while enabling the creation of new carrier-class data services built upon the existing network infrastructure. Additional information about CIENA can be found at www.ciena.com.

NOTE TO INVESTORS

This press release contains certain forward-looking statements based on current expectations, forecasts and assumptions that involve risks and uncertainties. These statements are based on information available to the Company as of the date hereof; and CIENA's actual results could differ materially from those stated or implied, due to risks and uncertainties associated with its business, which include the risk factors disclosed in its Report on Form 10-Q, which CIENA filed with the Securities and Exchange Commission on August 19, 2004. Forward-looking statements include statements regarding CIENA's expectations, beliefs, intentions or strategies regarding the future and can be identified by forward-looking words such as "anticipate," "believe," "could," "estimate," "expect," "intend," "may," "should," "will," and "would" or similar words. CIENA assumes no obligation to update the information included in this press release, whether as a result of new information, future events or otherwise.