Sam Bowne has been teaching computer networking and security classes at CCSF since 2000. He has given talks at CodeCamp, DEFCON, BayThreat, LayerOne, and Toorcon, and taught classes and seminars at many other schools and teaching conferences. He has a Ph.D. and a CISSP and a lot of other certifications, and a lot of computer and cables and firewalls and stuff.