Agent Tcl: A transportable agent system

Agent Tcl is a transportable-agent system that is under development at Dartmouth College. A transportable agent is a named program that can migrate from machine to machine in a heterogeneous network. Such programs are a powerful tool for implementing information agents since the electronic resources in a user's information space are often distributed across a network and can contain tremendous quantities of data. Sending a user-speci c program to the network location of the resource is often the most convenient and e cient alternative. The goal of Agent Tcl is to address the weaknesses of existing transportable-agent systems. Agent Tcl will run on standard hardware, support multiple languages and transport mechanisms, provide transparent migration and communication, and provide e ective security and fault-tolerance in the uncertain world of the Internet. This paper describes the architecture of Agent Tcl and its current implementation and presents four informationmanagement applications in which Agent Tcl has proven useful.