Page 2 Lecture Notes in Computer Science 2865 Edited by G. Goos ...
Page 2 Lecture Notes in Computer Science 2865 Edited by G. Goos ...
Page 2 Lecture Notes in Computer Science 2865 Edited by G. Goos ...
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
120 F. Gamba, J.-F. Wagen, and D. Rossieris made up of numerous classes and can thus be difficult to implement <strong>in</strong>to embeddedsystems.The Lightweight and Extensible Agent Platform (LEAP) 6 is a project aim<strong>in</strong>g at therealization of a FIPA platform that can be deployed seamlessly on any Java-enableddevice endowed with sufficient resources and with a wired or wireless connection,such as PDAs and smart phones [15]. LEAP significantly contributes to provid<strong>in</strong>gnetwork devices with an embedded agent platform.LEAP appears to be particularly <strong>in</strong>terest<strong>in</strong>g because it can easily be deployed <strong>in</strong> asimple Java processor based platform, which can be connected to any vendor<strong>in</strong>dependentaccess po<strong>in</strong>t. We are now <strong>in</strong>vestigat<strong>in</strong>g the deployment of ourAWM_agent <strong>in</strong>to a LEAP-based Java processor based platform.3.2 Agent BehaviorThe Jade agent platform [16] provides a novel approach towards task design withgeneric behaviors. Based on message exchanges between agents, several behaviorschemes correspond<strong>in</strong>g to various task types are def<strong>in</strong>ed <strong>in</strong> order to enable multiple<strong>in</strong>teractions with other agents.The behaviors are divided <strong>in</strong>to two ma<strong>in</strong> categories, respectively simple and compositebehaviors. A simple behavior consists <strong>in</strong> a task that is activated only once andcannot be blocked - oneShotBehaviour - or <strong>in</strong> a cyclically activated task. A compositebehavior is made up of several behaviors accord<strong>in</strong>g to a parent-child relationship; itmay consist of a sequential behavior - SequentialBehaviour - which executes the subbehaviorssequentially and term<strong>in</strong>ates when all sub-behaviors have been executed; onthe contrary, parallel behavior - ParallelBehaviour - allows the developer to implementsub-behaviors which can be executed <strong>in</strong> a non-determ<strong>in</strong>istic order. F<strong>in</strong>ally, abehavior can be described with a f<strong>in</strong>ite state mach<strong>in</strong>e (FSM); the parent behaviorcontrols the transitions between the FSM states and activates the behaviors correspond<strong>in</strong>gto the current state.From the communication po<strong>in</strong>t of view, the agents can <strong>in</strong>teract via <strong>in</strong>tra-platformcommunication: all the agents participat<strong>in</strong>g <strong>in</strong> the <strong>in</strong>teraction are managed <strong>by</strong> thesame platform; they reside <strong>in</strong> the same environment. The agents can also be distributedover several platforms, <strong>in</strong> which case they <strong>in</strong>teract via an <strong>in</strong>ter-platform communicationmechanism. In both cases, agents communicate via ACL messages. For example,if an agent platform is dedicated to one and only one access po<strong>in</strong>t, the hostedAWM_agent endowed with an SNMP manager can be logically perceived as the accesspo<strong>in</strong>t itself and only <strong>in</strong>ter-platform communication will take place. On the contrary,if an agent platform hosts several AWM_agents, the agent platform is responsiblefor manag<strong>in</strong>g several access po<strong>in</strong>ts, and <strong>in</strong>tra-platform communication will takeplace between the AWM_agents resid<strong>in</strong>g <strong>in</strong> the platform.3.3 AWM Agent ArchitectureIn our framework, an AWM_agent is dedicated to an access po<strong>in</strong>t and performs threebasic tasks: at first, the agent cont<strong>in</strong>uously monitors its local environment <strong>by</strong> query<strong>in</strong>gthe SNMP agent of the access po<strong>in</strong>t; the retrieval of particular values from MIB vari-6http://leap.crm-paris.com