关键词: 用户模型, 普适计算, MRGP, 可用性度量

Abstract: With the vision of anytime anywhere computing, the availability management is playing an important role in pervasive computing. Most research focus on the qualitative analysis. This paper adopts a quantitative approach to attack this topic. Due to the CTMC and SMP can not be applied to the modeling of the availability of pervasive computing system, which has the features of user oriented, non-exponential distributions and associative analysis between user states and system states, this paper presents an MRGP(Markov regenerative process)-based measurement for the availability of pervasive computing system. First, a bidirectional extended user model is developed, which provides a base point for describing the availability in pervasive computing. Second, an MRGP model for availability is establised, and a stochastic process-based analysis is conducted for the availability of pervasive computing system. The transient and steady availability analysis are provided for this model, and a novel availability metric, called request availability of pervasive computing system, is suggested. Finally, numerical analysis has been carried out and the results argue that the proposed approach and availability metric can give reasonable evaluation for pervasive computing system.

Key words: user model, pervasive computing, MRGP, availability