Renesys Issues Ranking of Global Service Providers Using Market Intelligence Solutions; Customer Base Index Ranks the Top Ten Carriers in North America, Europe and Asia.

MANCHESTER, N.H. -- Renesys Corporation, a leading provider of next-generation Internet Routing and Market Intelligence solutions, today released the first in a series of rankings that will compare service providers worldwide. Leveraging the power of the company's award-winning Market Intelligence Service, the Renesys Customer Base Index identifies and ranks carriers in North America, Europe and Asia in terms of transit presence in their respective geographic markets.

Much of the worldwide economy rests on the global network of carriers who provide Internet connectivity for most of the world's ISPs and corporate networks. These service providers rely on each other by exchanging customer traffic while also aggressively competing for the same customers. However, they may know comparatively little about each other's day-to-day operations on a global level. Renesys' Market Intelligence provides an objective, reliable view into the following metrics:

--Which service providers have the most customer networks?

--Which service providers are acquiring customer networks at the fastest rate?

--Which service providers are experiencing the least customer churn?

--Which service providers have the most customers with only one link to the Internet?

--Which service providers connect to the most customer networks, both directly and through peering relationships?

The Renesys Customer Base Index for the month of February 2006 showed the following results based on the criteria above across North America, Europe and Asia:

North America

1. Level 3 Communications, LLC
2. UUNET Technologies, Inc.
3. AT&T WorldNet Services
4. Sprint
5. Qwest
6. Cogent Communications
7. Savvis
8. Williams Communications, Incorporated
9. Global Crossing
10. Department Of Defense Network Information Center

Europe

1. Level 3 Communications, LLC
2. Sprint
3. TeliaNet Global Network
4. Global Crossing
5. Cable & Wireless
6. France Telecom
7. Telecom Italia Sparkle
8. Teleglobe Inc.
9. Deutsche Telekom AG
10. BT European Backbone

Asia

1. Sprint
2. NTT America, Inc.
3. China Telecom
4. KDDI Corporation
5. Savvis
6. UUNET Technologies, Inc.
7. JAPAN TELECOM CO.,LTD.
8. AT&T WorldNet Services
9. Level 3 Communications, LLC
10. Teleglobe Inc.

The Renesys Customer Base Index was created in three steps:

--A weight was assigned to each advertised network prefix in the global routing tables, estimating the total number of end-user systems that network represents.

--The weights were added for all of the network prefixes in a given geographic market that are seen "downstream" of a given provider -- that is, advertised by the provider, or by its customers.

--All providers who serve a given market were ranked in decreasing order of their total

Customer Base scores to create the Index.

"The rankings generated by Renesys Market Intelligence demonstrate the power of the solution to provide a new level of intelligence for service providers on a global scale," said James Cowie, Co-Founder and Chief Technology Officer of Renesys. "The most interesting ranking is for the Asian market, as network transit in this region is could be the driver of global Internet traffic over the next ten years. Given this, the rankings provide the industry with a preview of the service providers that could be atop the global rankings in the near future."

Renesys Market Intelligence (RMI) is the first and only continuously-updated information resource of its kind. Based on the evolution of the global service provider marketplace, it includes live data from global routing tables, which is therefore used to include real-time maps of more than 180,000 networks and 30,000 organizations worldwide. RMI showcases relative strengths and weaknesses of competing service providers, and includes global, national and regional rankings of service providers based on the number and quality of networks to which the competitor is linked.

About Renesys Corporation

Renesys offers the industry's first Internet performance monitoring and analysis solution that provides an unprecedented level of Internet intelligence for competitive advantage. The company gives service providers, government agencies and Global 2000 organizations, a real-time view into the Global Internet as it affects their business. Only with Renesys can customers have a new level of speed and agility in managing the Internet climate outside the four walls of the organization, resulting in minimal downtime between customers, partners and other stakeholders. Renesys was founded in 2000 and is based in Manchester, NH. For more information, visit www.renesys.com.