"From P2P to Web Services  and Grids"  provides a comprehensive overview of emerging distributed-systems technologies. It covers peer-to-peer (P2P) systems, which have revolutionized the way we think about distributed computing  and the internet, alternative solutions, most notably web services  and Grid computing, but also other technologies, such as client/server based systems  and distributed-object technologies. A wide range of middleware  and application-based technologies are covered, such as Jxta, Jini, Globus, Web services, OGSA, WSRF, SOAP, WSDL, Napster  and Gnutella, with emphasis given on the architecture employed  and security model chosen. Each technology  and its capabilities are analyzed in the context of the degree of centralization or decentralization they employ. A resulting taxonomy is created giving a context in which to consider the most advanced  and broad ranging distributed systems available today,   and provides an essential reference text for designing new distributed systems.