Abstract
Markov models are widely used for the analysis of availability of computer/communication systems. Realistic models often involve state space cardinalities that are so large that it is impractical to generate the transition rate matrix let alone solve for availability measures. Various state space reduction methods have been developed, particularly for transient analysis. In this paper, we present an approximation technique for determining steady-state availability. Of particular interest is that the method also provides bounds on the error. Examples are given to illustrate the method. © 1989 IEEE