TLRO based modeling of alternative commands and its application to generalized distributed resource allocation problem

Abstract

There are systems where alternative constructs need to be used for its description. In weakest precondition calculus disjunction of the post conditions of constituent guarded commands is used as the post condition of an alternative construct. Such representation is not suitable because it does not express a one to one correspondence between a guard and the relevant component of the characterized post condition. In this paper Temporal Logic Related to Observation (TLRO) is used to solve this problem. Each guarded command is expressed as a TLRO rule by using its strongest post condition and the corresponding precondition. List of these representations for all the constituent guarded commands is the required model. Technique is illustrated by considering a common sense scenario. The scheme is then applied to a generalized resource allocation algorithm which is a weaker version of Drinking Philosophers problem.