* Uses well-known commercial P2P systems as models, thus demonstrating real-world applicability. * Discusses how current research trends in wireless networking, high-def content, DRM, etc. will intersect with P2P, allowing readers to account for future developments in their designs. * Provides online access to the Overlay Weaver P2P emulator, an open source tool that supports a number of peer-to-peer applications with which readers can practice.