The Study, Based On The Collaborative Model Of Semantics And Access Policies

Massively parallel and distributed systems open new horizons for large applications and many applications already take advantage of the increased raw computational power provided by such parallel systems to yield significantly shorter turn-around times. Exploiting the full potential of massively parallel systems requires programming models that explicitly deal with the concurrency of cooperation among very large numbers of active entities that comprise a single application. The shared dataspace coordination models, represented by Linda, have the characteristic of temporal uncoupling, spatial uncoupling and referential uncoupling, indicate the development trend of massive programming and satisfy the requirements of software application in Internet that is open, dynamic and distributed. They have attracted great concern of the software technology research area.However, some problems exist in the current coordination models: one is lack of semantic information. The interactive entities can not understand the meaning of each other, so the further development is tempered in the open and distributed environment. The other is the access control in current models. Based on the above mentioned problems, the dissertation focuses on the agent coordination model with the background of multi-Agent system, and proposes a semantic and access policy based coordination model. Following efforts are presented in this dissertation:(1) Coordination model with semanticCombining OWL DL and rule of semantic web technology with Linda, a coordination model with semantic is proposed. In this model, semantic information is described by OWL DL, the tuplespace is presented as an ontology model. Analysis the new type of tuple, a new set of coordination primitives are defined and corresponding matching mechanism is proposed.(2) Access control policyThis dissertation uses declarative policy-based approach to control the behavior of the tuplespace, including:①OWL of semantic technology is used to define a access policy language applies to Linda.②the representation of policy rule, coordination operation and matching are solved.③an access policy reasoning algorithm is proposed to determine whether the agent has the right to carry out the operation.(3) The implementation of the coordination modelBased on the above two mentioned aspects, a part implementation of the semantic and access policy based coordination model-AccSTuple is presented. The work flow is presented and the application of the access policy is described by an instance. Key words: coordination technology, coordination model, Linda, semantic web...