Cyber Security Expert Barrett Lyon Brings Defense.net Out Of Stealth To Battle A New Wave Of DDoS Attacks

Cyber security expert and serial entrepreneur Barrett Lyon has a new startup coming out of stealth today. The company, named Defense.net, specializes in mitigating DDoS attacks — something Lyon knows a little something about. And it has raised $9.5 million from Bessemer Venture Partners to go after that market.

In 2003 Lyon founded Prolexis, one of the first network security firms to combat a growing wave of denial-of-service attacks. Back then, he was working mostly to fight off extortionist threats against online casinos, an effort that was immortalized in the book Fatal System Error. Since then, Lyon has founded a couple of firms working on content distribution — BitGravity and XDN (née 3Crowd).

But Lyon’s been drawn back into the online security game, helping businesses to fight a whole new wave of DDoS threats. A lot’s changed in the decade since he founded Prolexis — today’s DDoS attacks are larger, better organized, more distributed, and on the whole a lot more sophisticated.

But the biggest difference is that DDoS attacks today are no longer just the work of extortionists looking to make a quick buck, but so-called hacktivists, some of which might be government-sponsored, looking to cause real damage to online organizations. And so, it calls for a new type of network defense company. That’s what Defense.net hopes to be.

Defense.net CEO Chris Risley says that companies like banks and other organizations faced with DDoS attacks suffers from a concentration risk due to there being just a few companies out there. In that way, it could provide an alternative option to existing DDoS mitigation offerings from companies like Prolexis (still around) and Verisign. That could help banks and utilities and telecoms and Internet companies and the like.

The company is coming out of stealth today, with a team of 15. Most of those employees were engineers and DDoS mitigation experts who have been assembled from companies like Prolexic, Verisign, BitGravity, Juniper, Box.net and Apple’s security team. That includes Prolexic veterans Joe Daly and and Dan Murphy, who are Defense.net’s VP of Network Operations and Director of Systems Architecture, respectively. At the helm is CEO Risley, a veteran of highly-scalable Secure Data Management software companies.

Defense.net was incubated in the office of Bessemer Venture Partners, which led an investment in the startup. It has raised a total of $9.5 million led by Bessemer partner and Verisign co-founder David Cowan. Joining Cowan on the board of directors is Equinix, Digg, and Revision3 co-founder Jay Adelson.

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