Ches is an early innovator in Internet security. He is known for his work in firewalls, proxies, and Internet mapping at Bell Labs and Lumeta Corp. He is best known for the book he co-authored with Steve Bellovin and now Avi Rubin, Firewalls and Internet Security; Repelling the Wily Hacker.
Ches is now a member of the technical staff at AT&T Labs - Research in Florham Park, NJ, where he is working on security, visualization, user interfaces, and a variety of other things.