August 25, 2008

Blue Coat Senior Architect Honored With SIGCOMM’s Test of Time Award for TCP Performance Research

Blue Coat Systems, Inc. (Nasdaq:BCSI), the leader in WAN Application Delivery and Secure Web Gateway, today announced that SIGCOMM, ACM's professional forum for communications and computer networks, has recognized Blue Coat Senior Architect Jamshid Mahdavi for his groundbreaking paper, "The Macroscopic Behavior of the TCP Congestion Avoidance Algorithm," with the Test of Time award. This award recognizes research papers published 10-12 years ago that continue to provide useful contributions to today's research. The ability to increase TCP performance and provide congestion control is a fundamental building block of wide area network (WAN) optimization.

In the paper, Mahdavi and his co-authors, Matt Mathis, Internet engineer at the Pittsburgh Supercomputing Center, Jeff Semke, software engineer at Network Appliance, and Teun Ott, an independent researcher recognized for his work on TCP, lay out an analytical model that examines TCP performance to improve congestion control capabilities. By analyzing TCP performance as a function of network latency, packet loss rate and packet size, the paper presents a model that advanced innovations in congestion control.

"TCP is one of the foundational elements of communication over the network, and its ability to effectively manage congestion is essential to improving application performance across the wide area network," said Mahdavi. "This research was the basis for developments in congestion control techniques that are now a fundamental part of the technology used by Blue Coat to increase application performance."

The model described in the paper led to the development of scalable TCP, a critical technology that enhances performance across the wide area network and is implemented in Blue Coat(R) ProxySG(R) appliances. Blue Coat solutions provide visibility, security and control at the Internet gateway and over the Wide Area Network (WAN) while accelerating business-critical traffic and reducing bandwidth consumption. By efficiently managing congestion control and optimizing chatty web-based applications, ProxySG appliances improve the delivery of applications to the branch office.

In addition to creating a model for analyzing TCP performance, the research highlighted in the paper laid the groundwork for other innovations in the industry, including advancements in congestion control algorithms, router queuing and active queue management, and congestion control for unicast and multicast traffic. The research also helped spur the development of transport protocols to carry telephony traffic over the Internet and provided a basis for quantifying the effects of packet loss in wireless networks to resolve TCP performance issues.

About Blue Coat Systems

Blue Coat secures Web communications and accelerates business applications across the distributed enterprise. Blue Coat's family of appliances and client-based solutions - deployed in branch offices, Internet gateways, end points, and data centers - provide intelligent points of policy-based control enabling IT organizations to optimize security and accelerate performance between users and applications. Blue Coat has installed more than 40,000 appliances worldwide. Blue Coat is headquartered in Sunnyvale, California, and can be reached at (408) 220-2200 or

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