For reasons of economy and scalability, many of the current distributed computing systems (DCSs) are realized as an integration of prefabricated and deployed components offering specific services. A critical task that the assembler of such a system needs to address is to locate and select appropriate components scattered over a network. This requires solving many research challenges. These include: (a) deployment of components and their specifications, (b) efficient searching for and gathering of appropriate specifications, (c) representation of queries, and (d) semantics of matching between queries and specifications. UniFrame (Raje, Auguston, Bryant, Olson, & Burt, 2001) is a framework that allows the seamless discovery and integration of such distributed software components. It addresses three key research issues: (1) architecture-based interoperability, (2) distributed discovery of resources, and (3) quality validation. This article presents a mobile-agent-based discovery service, which is one of the alternatives developed under research issue (2).
