Research On Communication Of Mobile Agents

Mobile agent technology, which combines Artificial Intelligence(AI) with distributed computing, has been a hotspot in research of distributed computing and AI. Essentially, Mobile agent is an object that looks for cooperators in the Internet on behalf of a user, and cooperates with other agents in order to implement the task of the user. In a mobile agent system, the migration of mobile agents and the collaboration between mobile agents both depend on communication. Therefore, communication is very important for the mobile agent systems, and the quality of the tasks'fulfilling should be decided by the reliability of communication, and also cooperation is the essential demand of mobile agent. Cooperation is a very challenging issue of mobile agent key technology. At present, the cooperation of mobile agents mainly focuses on the research of communication mechanism.In traditional distributed computing model, the position of object is fixed and not changed in the whole life circle since it is created. So the message sender is easy to get the location of a target mobile agent for communication. But for a mobile agent, its position maybe changed frequently, the following problems need to be considered under mobile agent computing mode: Firstly, how to give a position independence naming method for mobile agent in distributed environment. Secondly, how to implement transparent locating of a mobile agent. Thirdly, how to handle messages that are sent to mobile agent when it is being in the procedure of migration. Finally, how to resolve the problem of communicating invalidation. Many researchers have put forward some kinds of solutions of agent location tracking, message storage and transfer for problems above, such as Broadcasting method, Link Tracing method, Home Proxy method Central Registration method, and etc. Although these methods have their advantages respectively, there are some disadvantages in tracing efficiency, expansibility and communication reliability.In order to resolve the problems above, this thesis proposes a reliable and high-performance mobile agent communication model. In this model, mailbox is used to be the transfer of message sending, which can also prevent the phenomenal of message chasing; The position information of mobile agent is not only stored in the home place of the agents,which is the computer where its mailbox is stored, but also stored in the computer where the agents is rest now, so that, the burden of its home place can be reduced, the neckbottle can be avoided, and the sudden-dead agents can be detected in time; Messages are divided into two parts,urgent messages and ecumenic messages, and ensure that the urgent messages can be sent to the target agents as soon as possible; Energy control mechanism is used, so that the useless agents can be detected through local communication, and the unlimitedly occupying of network and computer resources would never exist.Finally, we analyze the performance of this communication model, and compare it with other current typical models, then discuss its reliability, asynchronism,and stability. In general, this is a flexible-structured, high-performance and high-reliability model for mobile agent communication. These advantages make a good foundation for subsequent research.