Peer-to-Peer (P2P) networks enable users to directly share digital content (such as audio, video, and text files) as well as real-time data (such as telephony traffic) with other users without depending on a central server. Although originally popularized by unlicensed online music services such as Napster, P2P networking has recently emerged as a viable multimillion dollar business model for the distribution of academic and clinical information, telecommunications, and social networking. Written at an accessible level for any reader familiar with fundamental Internet protocols, Peer-to-Peer Networking and Applications explains the conceptual operations and architecture underlying basic P2P systems using well-known commercial systems as models. The book also delineates the latest research directions, thereby providing not only a sophisticated understanding of current systems, but also the means to improve upon these systems with innovations that will better performance and security.