Dependability analysis of distributed computer systems with imperfect coverage

In this paper a new algorithm based on Binary Decision Diagrams (BDD) for dependability analysis of distributed computer systems (DCS) with imperfect coverage is proposed. Minimum file spanning trees (MFST) are generated and stored via BDD manipulation. By using the multistate concept, our algorithm can generate BDDs that can deal with imperfect coverage and obtain reliability expressions from these BDDs. Ordering strategies for variables are discussed in this paper as well. Due to the nature of the BDD, the sum of disjoint products (SDP) can be implicitly represented which avoids huge storage and high computation complexity for large systems. Several examples are given to show the efficiency of this algorithm.