I was a Member of Technical Staff at AT&T Bell-Labs from 1985 to 1989. In 1989 I joined the computer science department at Tel-Aviv University. I was a consultant for AT&T research labs from 1988 to 2000. In 2001 I founded Riverhead Networks together with Anat bremler-Barr, Dan Touitou, and Yuval Rachmilevitch. Riverhead Networks is the only company to have succeeded in providing a solution to the problem of Distributed Denial of Service attacks on the Internet. The Riverhead Guard, as it is called, protects thousands of sites (including some from fortune-5, and many from fortune-500), keeping them up and running despite massive multi Gbps attacks over long periods of time. Riverhead was acquired by Cisco in 2004, after which I remained as a director in Cisco until May of 2009.