For almost as long as there have been computers, we have sought new and ever-better ways to build software so that programs running on multiple computers can work together. As in human endeavors, we find that coordinated efforts can produce better results than the separate efforts of the isolated. The distribution of computing across faster processors, using faster networks, brings new challenges and opportunities for systems that can scale, are secure, have good performance, and can tolerate faults in the software and hardware.

This issue will show how distributed computing technologies compare, and how they are used by government and military organizations. We kick things off with Ed Shrum’s article detailing military requirements for distributed computing technology and the Army's current directions. Next is John Kane’s article on the Intelligence, Surveillance, and Reconnaissance (ISR) Information Service (ISRIS), which describes how basic Web technologies and novel subscription services are combined to provide real-time services and data from today’s operational and developing ISR platforms. ISRIS shows what can be done with distributed computing today, where available resources and technologies joined in new ways can produce powerful capabilities.

Dock Allen's sidebar on real-time distributed computing illustrates the natural evolution of the technology to address concerns of highly reliable, embedded, and performance-constrained applications. Margaret Lyell’s article then explores the world of software agent architectures. In addition to comparing agents to other technologies, the article shows how to connect distributed agents to an existing system.

Stan Manoski reports on the U.S. Army’s plans to use peer-to-peer (P2P) computing in the era of the “TOC-less” Army; Paul Silvey’s sidebar on P2P computing augments the article from a technology perspective. David Slattery then examines the issue of authentication in distributed systems, an issue of critical concern to deployed troops. The issue concludes with Ed Shrum’s brief history of distributed computing, which places the preceding articles in the context of an evolving discipline.

For more information, please contact guest editors Eric Hughes or Kevin Kelly using the employee directory.