Avici Systems First Vendor to Successfully Complete Rigorous BTexact Benchmark Evaluation for Core Routers.

Business/Technology Editors

N. BILLERICA, Mass.--(BUSINESS WIRE)--May 21, 2002

Proves Carrier-Class Reliability, Scalability

and Performance of Product

Avici Systems Inc. (Nasdaq: AVCI), the specialist in high reliability routing solutions for the Internet, today announced the successful completion of BTexact Technologies' testing of the TSR(TM)core router platform against its rigorous Carrier Class Benchmark.

In February 2002, BTexact, British Telecom's advanced research and technology business, issued a challenge to the core router industry outlined in its "Carrier Requirements of Core IP Routers" Benchmark Study. This study surveyed leading global carriers and prioritized the key requirements for core routers, setting the new standard by which routers are evaluated. Reliability, scalability and operational performance were identified as the top three requirements of core router platforms.

According to Dr. Tony Dann, head of the IP Test and Evaluation at BTexact Technologies, "The continued growth of IP traffic and the increasing need to support value-added IP services requires carriers to look to a new generation of routers which can deliver five nines reliability, non-disruptive scalability and robust operational performance. We are pleased that Avici Systems had the confidence to accept our Carrier Class Benchmark challenge, and our tests show the TSR delivers real advances in several of these key areas."

The BTexact team evaluated Avici's products against requirements in seven categories including reliability, scalability, performance, feature support, management, interoperability and security. In contrast to traditional router performance tests, each of the BTexact tests were designed to replicate the stresses of real-world carrier networks with multiple protocols and management tasks running simultaneously.

Evaluation Report Excerpts:

-- "The TSR was found to support wire-speed forwarding of packets on all tested
interfaces with low latency and carrier-scale implementations of the major
routing protocols."

-- "In our opinion, the provision of a duplicated server, resilience mechanisms
such as composite trunking, and the regression testing of software do indicate
the TSR has been designed to address the carriers' requirement for reliability
and stability."

-- "These tests indicate the TSR can accommodate both the range of protocols
and the scale of implementations required by carriers."

-- "The TSR has the interface range required by today's carriers, and higher
rate IP links can be created through the Composite Link(TM) technology."

-- "Interoperability using all of the major protocols was demonstrated over a
variety of interfaces with routers from Cisco and Juniper. Avici passed all of
the tests with no concerns."

"It is gratifying for Avici's TSR to be the only core routing platform which has successfully completed BTexact's rigorous evaluation against the Carrier Requirements Benchmark," said Chris Gunner, senior vice president of research and development at Avici Systems.

Avici is the only router vendor that has designed and deployed an Internet core router designed specifically for carriers. Avici's family of carrier-class routers enables service providers to grow from five Gbps to over five Tbps of capacity as their demand increases. Avici's unique distributed Velociti(TM) architecture, robust IPriori(TM) software, and NSR(TM) non-stop routing technology deliver the highest levels of network reliability while lowering the cost of building and operating IP networks.

The summary evaluation report is available on Avici's web site at: www.avici.com.

The BTexact Carrier Requirements of Core IP Routers 2002 Benchmark Study is available at: http://www.btexact.com/ideas/whitepapers.

About Avici Systems

Avici Systems Inc., headquartered in North Billerica, Mass., is a leading provider of purpose-built carrier-class routing solutions for the Internet. Avici's family of routers is designed to meet carrier requirements for the highest scalability, reliability and network availability, while lowering the total cost of building and operating their networks. The company's routing systems provide new IP solutions to some of the world's leading service providers. For more information, please visit us at www.avici.com.

Avici, TSR, SSR, Velociti, IPriori, and NSR are trademarks of Avici Systems Inc.

This release contains information about Avici's future expectations, plans, and prospects that constitute forward-looking statements for purposes of the safe harbor provisions under the Private Securities Litigation Reform Act of 1995. Such forward-looking statements are subject to risks and uncertainties, which could cause actual results to differ materially from those anticipated. When used in this press release, the word "will", "expected" and other similar expressions are intended to identify such forward looking statements. Such risks and uncertainties include, but are not limited to, market acceptance of Avici products, services and enhancements, customer purchasing patterns and commitments, development of the market place, product development and enhancement, intensity of competition of other vendors, technological changes and other risks set forth in Avici's filings with the Securities and Exchange Commission.