The traditional fortress mentality of system security has proven ineffective to attacks by disruptive technologies. This is due largely to their reactive nature. Disruptive security technologies, on the other hand, are proactive in their approach to attacks. They allow systems to adapt to incoming threats, removing many of the vulnerabilities exploited by viruses and worms. 'Disruptive security technologies with mobile code' and Peer-To-Peer Networks provides a foundation for developing these adaptive systems by describing the design principles and a security paradigm embracing disruptive technologies. In order to provide a through grounding, the author covers such topics as mobile code, robust peer-to-peer networks, the multi-fractal model of network flow, security automata, dependability, quality of service, mobile code paradigms, code obfuscation, and distributed adaptation techniques as part of system security.