Distributed operating systems have many aspects in common with centralized ones, but they also differ in certain ways. This paper is intended as an introduction to distributed operating systems, and especially to current university research about them. After a discussion of what constitutes a distributed operating system and how it is distinguished from a computer network, various key design issues are discussed. Then several examples of current research projects are examined in some detail, namely, the Cambridge Distributed Computing System, Amoeba, V, and Eden.

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RFID (Radio Frequency Identification) systems are one of the most pervasive computing technologies with technical potential and profitable opportunities in a diverse area of applications. Among their advantages is included their low cost and their broad applicability. However, they also present a number of inherent vulnerabilities. This paper develops a structural methodology for risks that RFID networks face by developing a classification of RFID attacks, presenting their important features, and discussing possible countermeasures. The goal of the paper is to categorize the existing weaknesses of RFID communication so that a better understanding of RFID attacks can be achieved and subsequently more efficient and effective algorithms, techniques and procedures to combat these attacks may be developed.

ast@cs.vu.nl; www.cs.vu.nl/~ast. www.computer.org/internet/ Stay on Track IEEE Internet Computing reports emerging tools, technologies, and applications implemented through the Internet to support a worldwide computing environment.