Sycamore Networks Demonstrates Standards-Based Control Plane Interoperability in Leading Edge IP/Optical Test Event.

ASON/GMPLS-Compliant SN 16000 Intelligent Optical Switch Showcases Dynamic 10 Gigabit End-to-End Ethernet Connectivity and Control Plane Resiliency

CHELMSFORD, Mass. -- Sycamore Networks, Inc. (NASDAQ: SCMR), today announced its SN 16000 intelligent optical switch successfully demonstrated standards-based control plane interoperability in a multi-vendor event that featured a diverse range of next-generation IP/MPLS applications and services running over a dynamic optical core. Held in conjunction with the MPLS 2006 conference, the Isocore Leading Edge Code (LEC) test event showcased the current state of multiservice interworking and multicast applications across a resilient, hybrid optical transport network, and included participation from industry-leading IP, MPLS and optical networking equipment vendors.

During the independent test event, Sycamore SN 16000 intelligent optical switches successfully demonstrated multi-vendor IP/Optical control plane interworking using standards-based Generalized Multi-Protocol Label Switching (GMPLS). The scope of the test effort, which included validation of GMPLS UNI models and MPLS-to-GMPLS migration strategies, reinforces the carrier-class performance, scalability and reliability of Sycamore intelligent optical switching solutions.

Highlights of the multi-vendor interoperability test event included:

Next-Generation Multiservice Interworking

The large network built for this demonstration provided network operators the opportunity to evaluate the current state of a wide range of next-generation applications including multiservice interworking, Video-on-Demand (VoD), inter-provider Layer 2/Layer 3 network services, and IPv6 enabled VPNs. The interoperability event also featured the industry's first validation of IPTV service delivery over Virtual Private LAN services implemented across a dynamic Ethernet transport infrastructure.

Dynamic 10 Gigabit Ethernet Service Connectivity

Growth in high-bandwidth applications such as Storage Area Networking continues to drive demand for flexible, cost-effective Ethernet transport services. In a multi-vendor test that included core IP routers as client devices, SN 16000 optical switches successfully demonstrated dynamic, end-to-end provisioning of 10 Gigabit Ethernet Label Switched Paths (LSPs) in a hybrid IP/Optical application using GMPLS User Network Interface (UNI) control plane signaling. This advanced capability was enabled by the Universal Service Card (USC), a modular service interface card for the SN 16000 that supports a variety of interface types, port speeds, and transport options in a single line card.

Control Plane Resiliency

Demonstrating the ability of the optical transport network to recover from control plane failures using Graceful Restart mechanisms as defined for IETF-based GMPLS signaling was one of the key objectives for the interoperability event. With multiple network services carried across GMPLS LSPs, participating vendors successfully demonstrated Graceful Restart interoperability and the ability of network services to remain unaffected in the event of a control plane failure. The IP/Optical application testing also included the industry's first validation of graceful recovery mechanisms for dynamically signaled 10-GigE-over-SONET LSPs.

"Validating unified control plane interoperability in a multi-vendor broadband environment provides key proof to network operators that standards such as ASON and GMPLS have reached a level of maturity necessary to support new high-bandwidth services such as Video on Demand or ubiquitous IPTV," said Kevin Oye, Vice President of Systems and Technology at Sycamore Networks. "During this test event, Sycamore further reinforced its leadership position in control plane technologies with the demonstration of dynamic end-to-end 10 Gigabit Ethernet connectivity in a multi-vendor IP/Optical network."

Sycamore Networks is a leader in the development and implementation of standards-based control plane technology, with an open systems architecture designed to support industry initiatives such as the IETF's GMPLS protocols; the Optical Internetworking Forum's UNI and NNI interfaces; and the International Telecommunication Union, Telecommunication Standardization Sector's (ITU-T) Automatic Switched Optical Network (ASON) reference architecture. Sycamore optical switching solutions support emerging control plane standards and traditional provisioning processes and protection mechanisms on the same platform, which enables network operators to pragmatically and non-disruptively introduce advanced features into their network.

About Sycamore Networks

Sycamore Networks, Inc. (NASDAQ: SCMR) is a leading provider of intelligent networking solutions for fixed line and mobile network operators worldwide. From multiservice access networks to the optical core, Sycamore products enable network operators to lower overall network costs, increase operational efficiencies, and rapidly deploy new revenue-generating services. Sycamore's global customer base includes Tier 1 service providers, government agencies, and utility companies. For more information, please visit www.sycamorenet.com.

We wish to caution you that certain matters discussed in this news release constitute forward-looking statements that involve risks and uncertainties. Readers are cautioned that actual results or events could differ materially from those stated or implied in forward-looking statements. These risks and uncertainties include, but are not limited to, risks relating to the formal investigations commenced by the Securities and Exchange Commission and the U.S. Attorney's office with respect to certain stock options granted by the Company, additional actions and findings that may result from the Company's investigation into the accounting treatment for stock options, the inability of the Company to file its Annual Report on Form 10-K on a timely basis and the issuance of a delisting notice by Nasdaq. Certain additional risks are set forth in more detail in the section entitled Factors that May Affect Future Results in the Company's most recently filed Form 10-Q, Form 10-K and the other reports filed by the Company from time to time with the Securities and Exchange Commission. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future results or otherwise.