Ciena Delivers Pseudowire and Advanced Ethernet Interworking Enhancements for DN 7000 Series FlexSelect Multiservice Switching Products.

LINTHICUM, Md. -- Ciena Corporation (Nasdaq: CIEN):

--Critical tools for transitioning broadband aggregation, business services and wireless backhaul to Carrier Ethernet and MPLS backbones added to next-generation edge platform with industry-leading reliability and scalability

Ciena(R) Corporation (Nasdaq: CIEN), the network specialist, today announced availability of key enhancements to its pseudowire emulation edge-to-edge (PWE3) and advanced Ethernet interworking capabilities on the DN 7000 Series FlexSelect(TM) Multiservice Edge Switching and Aggregation Platform. Key application requirements addressed by the latest developments include migrating DSL aggregation from ATM to Ethernet, delivering access technology-agnostic Layer 2 MPLS VPNs and consolidating 2G/3G TDM, Ethernet, and ATM-based wireless backhaul onto a converged radio access network (RAN).

As the infrastructures utilized to deliver triple play, business data and 3G wireless services become increasingly Ethernet and MPLS-centric, service providers continue facing the challenge of maintaining a profitable mix of new and legacy networks and services. The latest enhancements to Ciena's DN 7000 product family provide support for seamless interworking of TDM, Frame Relay and ATM with new advanced services delivered natively across Ethernet or over MPLS, while more efficiently supporting legacy customers and reducing capital and operational expenditures through network consolidation.

"Pseudowire technology has a significant role to play throughout the entire network, and the technology is well-positioned to take center stage as a cost-effective and flexible solution to service providers' converged infrastructure plans," said Scott Clavenna, chief analyst at Heavy Reading. "And, advanced Ethernet interworking functionality provides a solution to help carriers transition the network edge as they continue to optimize their infrastructures and services around a portfolio of advanced IP and Ethernet-based communications."

Ciena's DN 7000 Series is next-generation multiservice edge market leader with deployments at multiple Tier 1 carriers including AT&T and Verizon, as well as other large wireline and wireless service providers.

All of DN 7000 series' pseudowire and advanced Ethernet interworking capabilities are standards-based implementations proven in several MFA Forum, multi-vendor Ethernet and MPLS interoperability demonstrations. Some key features include:

--Multiservice Flexibility - supports Address Resolution Protocol (ARP) Mediation defined by the IETF for Ethernet to ATM/FR service interworking; RFC 1483/2684 and RFC 1490/2427 for Ethernet to ATM/FR network interworking; full suite of multiservice pseudowires - Ethernet, TDM, ATM and Frame Relay; and the MFA Forum's ATM-MPLS interworking standard.

--Scalability - patent-pending Learning Virtual Connection (LVC) functionality for a unique but standards-based approach to overcoming Ethernet virtual local area network (VLAN) scalability issues when interworking with ATM, particularly in DSL aggregation-including support for DSL Forum's WT-101. Also supports several hundred thousand pseudowires per platform to accommodate high-growth traffic and large installed bases of legacy customers.

--Reliability, OAM & QoS - the DN 7000 series platforms are the only data products to deliver six-nines (99.9999%) system availability along with strict priority queuing and multiple QoS levels for ensuring service level agreements. Support for MPLS resiliency via Fast Re-route, LSP ping and traceroute, and Virtual Circuit Connection Verification (VCCV) to ensure reliability, ease of operations and performance monitoring.

"These DN 7000 Series enhancements deliver a multiservice 'insurance policy' for seamless network migration, preventing service disruption and subsequent risk for customer churn while service providers migrate their installed base of customers to more advanced Ethernet and IP access services," said Steve Alexander, chief technology officer at Ciena. "This upgrade also underscores the integral role DN 7000 products play as networks evolve, and increased scalability, reliability and advanced service interworking is required to keep pace with the growth in triple play, Carrier Ethernet and wireless backhaul services."

About Ciena's DN 7000 Series

Ciena's DN 7000 FlexSelect Multiservice Edge Switching and Aggregation Platforms offer a wide spectrum of cost-effective Ethernet and IP/MPLS service delivery from modern data-aware access networks to the traditional edge of the core. The product family, which has completed the Telcordia OSMINE Services process, provides industry-leading pseudowire and virtual circuit scalability coupled with 99.9999% carrier-class reliability. The DN 7000 Series includes three product models that share common hardware and software, thereby decreasing sparing requirements and simplifying system operation and management, and is support by ON-Center, Ciena's network and service management platform.

All Ciena products, including the DN 7000 Series, are supported by Ciena's Global Network Services (GNS) portfolio of deployment, maintenance and professional services to help customers cost-effectively transition their networks to enable new services while supporting legacy applications and protecting investment.

ABOUT CIENA

Ciena Corporation is the network specialist, focused on expanding the possibilities for its customers' networks while reducing their cost of ownership. The company's systems, software and services target and cure specific network pain points so that telcos, cable operators, governments and enterprises can best exploit the new applications that are driving their businesses forward. For more information, visit 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 June 1, 2006. 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.