Bob Larson, CCNA, CCNP, CCDP, CCDA, teaches technology courses at the University of Washington's Information School graduate programs. He served on the Cisco Networking Academy's Advisory Board.Matt Walker, CCNA, CEH, CPTS, CNDA, is an IT security architect working for Hewlett-Packard on numerous projects. He has held a variety of networking and IT security positions, including most recently the IT security manager position at Marshall Space Flight Center (SAIC contract) and Kennedy Space Center (Lockheed Martin contract).