F5 Strengthens Its Worldwide No. 1 Market Share Position in Application Delivery Controllers.

Leading industry analyst firm reports that F5 has demonstrated strong growth and increased its market share lead

SEATTLE -- F5 Networks, Inc. (Nasdaq:FFIV), the global leader in Application Delivery Networking, today announced that it continues to hold the number one position in the Application Delivery Controller (ADC) market. In a recently published Gartner report, Market Share: Application Acceleration Equipment, Worldwide, 3Q061, F5 is leading the ADC sector with 33.4 percent worldwide 3Q06 market share based on manufacturer revenue. F5 also continues to dominate the advanced platform ADC subsegment, capturing 59.8 percent of the worldwide market in 3Q06.

"Increasingly, customers are recognizing that the successful delivery of applications depends upon the network's ability to understand the particular needs of an application, which is fueling the demand for F5's BIG-IP solutions and its flexible TMOS platform," said Erik Giesa, VP of Product Management and Marketing at F5. "As a company, F5 is the only vendor completely focused on application delivery and our market share lead in Application Delivery Controllers is powerful evidence of our commitment to this market. Our strong 40 percent growth over the last fiscal year was driven by the increasing demand of our BIG-IP application delivery platform."

F5's ADC offering combines the BIG-IP high-performance hardware platforms with BIG-IP v9 software for a comprehensive, advanced solution that delivers industry-leading application security, optimization, and availability. TMOSCoF5's intelligent, modular and scalable architectureCobrings key differentiators to the market, including the only full IP application proxy, iRules[TM] programming language, TCP Express, and iControl[TM] application integration interface. To assist customers and partners in leveraging iRules and iControl, F5 created DevCentral. As the only web site and community on the Internet that offers practical, real-world solutions and discussions, DevCentral helps to bridge the gap that has existed between application developers and network professionals.

For related research on the Application Delivery market, read Gartner's Magic Quadrant for Application Delivery Products, 2005, found here: http://mediaproducts.gartner.com/reprints/f5networks/article1/ article1.html (Due to its length, this URL may need to be copied/pasted into your Internet browser's address field. Remove the extra space if one exists).

1 Market Share: Application Acceleration Equipment Worldwide, 3Q06, Joe Skorupa December 2006, Gartner, Inc.

About F5 Networks

F5 Networks is the global leader in Application Delivery Networking. F5 provides solutions that make applications secure, fast and available for everyone, helping organizations get the most out of their investment. By adding intelligence and manageability into the network to offload applications, F5 optimizes applications and allows them to work faster and consume fewer resources. F5's extensible architecture intelligently integrates application optimization, protects the application and the network, and delivers application reliabilityCoall on one universal platform. Over 10,000 organizations and service providers worldwide trust F5 to keep their applications running. The company is headquartered in Seattle, Washington with offices worldwide. For more information, go to www.f5.com.

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