Mobile Agents are soft-wares migrating from one node to another to fulfill the task of its owner. Mobile agents are not properly utilized because of security concerns. One such concern is 'Denial of Service', in it the malicious host might deny resources required by the agent and kill the agent, thus the result computed so far is lost and this might happen every time the agent visits any malicious host. This paper is an extension of our work [12] in it we extend the concept to hierarchical model by grouping similar hosts together and finally detects the malicious host to prevent Denial of Service Attack. Simulation is done using CPN tools, Colored Petri Nets (CPNs) is a language for the modeling and validation of systems in which concurrency, synchronization and communication play a major role [3].

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Hierarchal Model Mobile Agent Denial Of Service Attack Colored Petrinets Group In Charge