WESTFORD, Mass. –December 19, 2006—NetScout® Systems, Inc. (NASDAQ: NTCT), a leading provider of enterprise-wide network and application performance management products and solutions, today announced that US Airways (NYSE: LCC) is using NetScout’s nGenius® Performance Management Solution to proactively ensure the performance of online reservation and information services and corporate networks. The airline chose the nGenius Solution for its ability to provide detailed, comprehensive views of the networks and applications supporting its corporate Web site.

US Airways, following its merger with America West Airlines, is the fifth largest domestic airline, employing more than 35,000 aviation professionals operating 3,800 daily flights to 234 communities in the United States, Canada, Europe, the Caribbean and Latin America. US Airways’ Web site generates more than $7 million in revenue per day on average, in addition to receiving millions of hits from customers checking flight schedules or conducting advance check-in.

“In the highly competitive arena of online travel booking, every second of responsiveness in the Web site counts,” said Tom Volante, senior manager of network operations at US Airways. “The root causes behind application slowdowns can be complex, making a quick diagnosis impossible unless you have a detailed understanding of what is running in the network links surrounding the site. With NetScout’s nGenius Performance Management Solution, we can immediately analyze the utilization of every application within a link. Without a doubt, NetScout provides the most complete picture for diagnosing performance problems of networked applications such as degradations.”

For example, US Airways used the nGenius Solution to identify the source of a significant slowdown on its Website impacting a number of online functions. It took US Airways network staff just 15 minutes to isolate a problem that would have taken hours or days to find previously. A third-party travel site was abnormally accessing several Web servers at up to ten times the normal rate, eating up bandwidth and slowing performance. US Airways blocked the offending application traffic until the partner could reconfigure it. Left unresolved, the problem would definitely have interrupted business transactions, likely driving customers to another airline.

“The ROI we have seen from the nGenius Solution was quick and significant,” Volante continued. “We can now contain the impact of application slowdowns on Web business. Operationally, the consolidation of key functions into a single product has increased our efficiency, while improving our ability to demonstrate the business impact of capacity and other technology issues to our executives.”

Eileen Haggerty, director of solutions marketing at NetScout Systems, said, “US Airways’ story typifies how IT leaders can use the nGenius Solution to manage business risks represented by information technology, eliminate management tool clutter and begin a proactive network and application performance management program.”

About NetScout Systems
NetScout Systems, Inc. (NASDAQ: NTCT) is a market leader and pioneer of integrated network and application performance management products and solutions that assure critical business services across the enterprise. More than 3200 organizations worldwide have deployed NetScout's nGenius® Performance Management System to increase their return on infrastructure investments by optimizing the performance of networks and applications according to business priorities. NetScout is headquartered in Westford, Massachusetts and has offices worldwide. Further information is available at http://www.netscout.com.

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