F5's BIG-IP Product Delivers Mission-Critical Availability, Easy Scalability, and Enhanced Security to Microsoft Office Live Communications Server 2005 Deployments.

SEATTLE -- F5 Has Completed Comprehensive and Exhaustive Product and Performance Testing to Ensure Delivery of an Enterprise-Ready Instant Messaging Solution

F5 Networks, Inc. (Nasdaq:FFIV), the global leader of Application Traffic Management products, today announced that its BIG-IP(R) product has been thoroughly tested and validated to work with Microsoft Office Live Communications Server 2005. Tight collaboration between F5 and Microsoft resulted in the successful interoperability testing and documentation of joint BIG-IP and Live Communications Server product deployments, which gives customers a prescriptive solution with the assurance of lower cost and risk. The BIG-IP product's unique capabilities, including its "application fluency" applied toward SIP (Session Initiation Protocol)-enabled networks, have been proven and documented.

"Live Communications Server 2005 delivers enterprise-grade instant messaging and presence, and a platform for enterprise real-time communications. It connects people, information, and business processes in real-time -- enabling better decisions faster," said Marc Sanders, Senior Product Manager, Real-Time Collaboration at Microsoft. "Microsoft's Live Communications Server 2005 version delivers a powerful and effective enterprise grade instant messaging platform that is built to accommodate up to 125,000 concurrently active clients and encompasses service availability, superior performance and security. BIG-IP provides the building blocks necessary to achieve our customers' required levels of availability and reliability in a SIP-enabled network."

Deployment of real-time collaboration, presence and instant messaging (IM) solutions are on the rise as enterprises strive to communicate more effectively, efficiently, and provide better tools to make good business decisions, as corporations move to the next level of productivity improvements. The BIG-IP product enhances the Microsoft solution by providing the ability to add and remove servers on-the-fly, implement health monitoring of servers, enable virtualization, and direct client traffic based on a set of sophisticated metrics, features that ease corporate data center deployments of Microsoft's Live Communications Server product.

"In our research we have seen tremendous interest by enterprises to adopt enhanced communication services like IM, video, and presence," said Matthias Machowinski, Directing Analyst, Enterprise Voice and Data, Infonetics Research. "The extensive interoperability work accomplished between F5 and Microsoft will allow enterprise organizations to deliver these services in a secure and robust manner that enhances overall performance of real-time applications."

"F5 recognized the importance of SIP and converged data and voice networks over three years ago when we offered the first SIP-capable traffic management solution," said Jim Ritchings, Vice President of Business Development at F5 Networks. "We're pleased that BIG-IP's advanced capabilities mesh so well with Microsoft's Live Communications Server to create a joint solution that delivers enterprise class reliability, scale, security and performance. This is yet another proof point of the benefits that can be achieved when applications and the network work in concert."

About F5 Networks

F5 enables organizations to successfully deliver business-critical applications and gives them the greatest level of agility to stay ahead of growing business demands. As the pioneer and global leader in Application Traffic Management, F5 continues to lead the industry by driving more intelligence into the network to deliver advanced application agility. F5 products ensure the secure and optimized delivery of applications to any user -- anywhere. Through its flexible and cohesive architecture, F5 delivers unmatched value by dramatically improving the way organizations serve their employees, customers and constituents, while lowering operational costs. Over 6,000 organizations and service providers worldwide trust F5 to keep their businesses running. The company is headquartered in Seattle, Washington with offices worldwide. For more information go to www.f5.com.

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