Service Availability in Concurrent Systems - Part II: Analysis and Case Studies Using HSIP

The problem of service availability is analyzed using the model developed in Part I. It is shown that the general service availability problem is undecidable, i.e. there is no single algorithm to determine whether a given service in a given system is available at a given time. In restricted cases, it is shown that the problem is decidable, but is NP-complete. The problem of service availability is then extended to nondeterministic systems. Finally, it is shown that a number of important cases can be studied in a cohesive manner based on our proposed formalism.