David is an old-school, dumb-terminal kind of UNIX geek who's always been fascinated by password cracking. Past work in this area has included distributed password cracking, pattern-based dictionaries, and building Rainbow tables for salted passwords. Currently employed by Intrepidus Group, David performs assessments on web applications, mobile devices, and occasionally networks. His alter ego, Darth Null, greatly enjoys solving puzzle contests at security conferences.