In the late 1990s, AI witnessed an increasing use of the term 'argumentation' within its bounds: in natural language processing, in user interface design, in logic programming and nonmonotonic reasoning, in Al's interface with the legal community, and in the newly emerging field of multi-agent systems. It seemed to me that many of these uses of argumentation were inspired by (of­ ten inspired) guesswork, and that a great majority of the AI community were unaware that there was a maturing, rich field of research in Argumentation Theory (and Critical Thinking and Informal Logic) that had been steadily re­ building a scholarly approach to the area over the previous twenty years or so. Argumentation Theory, on its side; was developing theories and approaches that many in the field felt could have a role more widely in research and soci­ ety, but were for the most part unaware that AI was one of the best candidates for such application.

We dedicate this book to students 0/ computer science who want to under­ stand why the radio channel is at the heart of mobile communications, be it data or voice, and to students 0/ communications engineering looking for an introduction to the structure of the Internet protocols, and their application to mobile radio. We also welcome the practicing engineer' working for mobile network operators and infrastructure suppliers, and the application program­ mer looking for the underlying reasons for the problems they encounter in their daily work. Given that convergence of the information technology and communica­ tions worlds has been talked about for almost 20 years, there is still surpris­ ingly little knowledge among specialists of each others' fields. Data communi­ cations over radio, notably Internet access, however, requires fuH understand­ ing of both fields. Internet protocols have been designed for fixed networks. There bit errors are so rare that interrupted transmission almost inevitably means congestion. In contrast, the radio channel constitutes a bottleneck for mobile data communications in that it introduces bit errors even at modest data rates. This book is based on the doctoral thesis of one of us (M. Taferner).

Peers In A Client Server Worldô provides a comprehensive overview of emerging peer-to-peer (P2P) technologies that have revolutionized the way we think about distributed computing and the internet. These technologies are compared to alternative solutions, most notably web services and Grid computing but also other technologies, such as client/server based systems and agent technologies. A wide range of diverse middleware and application-based technologies are covered, such as JXTA, Jini, Globus, Web services, OGSA, J2EE, Napster and Gnutella, with an 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 that gives the reader a context in which to consider the most advanced and broad ranging distributed systems available today, and provides them with an essential reference text for designing new distributed systems.

Informatik ist der Schlüssel, um unsere zunehmend digitalisierte Welt zu verstehen! In diesem Buch lesen Sie nicht nur, wie Navis den günstigsten Weg bestimmen, wie so viele Bilder auf eine kleine Speicherkarte passen oder welche Dinge ein Computer eben nicht ausrechnen kann. Mit Papier und Bleistift und den Bastelvorlagen können Sie die Antworten auf diese und viele weitere Fragen selbst buchstäblich begreifen. Ein Computer ist dafür nicht nötig!