Ebook: Mobile Agents and Security

New paradigms can popularize old technologies. A new standalone" paradigm, the electronic desktop, popularized the personal computer. A new connected" paradigm, the web browser, popularized the Internet. Another new paradigm, the mobile agent, may further popularize the Internet by giving people greater access to it with less eort. MobileAgentParadigm The mobile agent paradigm integrates a network of computers in a novel way designed to simplify the development of network applications. To an application developer the computers appear to form an electronic world of places occupied by agents. Each agent or place in the electronic world has the authority of an individual or an organization in the physical world. The authority can be established, for example, cryptographically. A mobile agent can travel from one place to another subject to the des- nation place’s approval. The source and destination places can be in the same computer or in di erent computers. In either case,the agentinitiates the trip by executing a go" instruction which takes as an argument the name or address of the destination place. The next instruction in the agent’s program is executed in the destination place, rather than in the source place. Thus, in a sense, the mobile agent paradigm reduces networking to a program instruction. A mobile agent can interact programmatically with the places it visits and, if the other agents approve, with the other agents it encounters in those places.

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The mobile agents paradigm integrates a network of computers in a novel way and, in a certain sense, reduces networking to program construction. A mobile agent can travel from one place to another and, subject to the destination's approval, interact programmatically with the place it visits. Besides a good deal of promise, mobile agents also introduce new problems. Most of these problems have to do with security and safety. Some of the security concerns have been studied by the distributed systems community and cryptologists for a long time, but mechanisms and technologies developed to secure communication and control access to resources must be adapted to take into account mobility and protection of mobile agents from malicious hosts.