MANET下环境感知的服务可用性量化评估模型

Environment-Aware Quantitative Assessment Model for Service Availability in MANET

移动Ad hoc网络(MANET)环境下,移动节点通过向其他节点提供服务是进行资源共享与能力协同的有效方式.但是由于 MANET环境的复杂性、链路的动态性和节点的异构性等特点,使得服务可用性时刻都在发生变化,且难以量化.通过对 MANET环境下服务运行环境和对影响服务可用性的节点、网络环境可用性的分析,提出了一个具有环境感知能力的服务可用性量化评估模型EQAM-SA,该模型由服务请求触发,实时获取服务运行参数、量化评估指标,并采用层次分析法和多属性综合评估法对服务的可用性进行量化评估.最后通过仿真实验验证了EQAM-SA的可行性和有效性.

In mobile ad hoc networks（MANETs）,mobile nodes share resources and collaborate to do work by using Web service technologies,and the service is defined as any hardware or software entity that resides on a mobile device or platform.However,the complex environment,dynamic network links and heterogeneous terminals make the service availability constantly vary and be difficult to assess in quantitative model.In this paper,after analyzing the running environment of services and the environmental factors that impact the service availability,an environment-aware quantitative assessment model for service availability（EQAM-SA） is proposed,which is touched off by the service requesting.In EQAM-SA,the running parameters of services are obtained and the quantitative evaluation indicators are then computed in real time as soon as a service request is received.The weights of these indicators are different and are used to assess services availability in different application scenarios,so Delphi approach is used to determine the weights.Then,the analytic hierarchy process（AHP） approach and multi-attribute evaluation with a weighted sum model are adopted to evaluate the service availability.Finally,the feasibility and effectiveness are validated by numbers of simulations.