Joint-State Modelling for Open Queuing Networks with Breakdowns, Repairs and Finite Buffers

Networks of queues are extensively used in modelling transaction processing systems and nodes in communication networks. Today, many practical queuing systems with finite queuing capacity are widely used in communication and computing. In such systems, servers are prone to failures. In this paper, the performance modelling of a multi-node system, with finite capacity heterogeneous nodes, serving internal and external arrivals of jobs is considered. An analytical model has been developed, and solved for performability measures. Joint-state modelling approach is used for this purpose. In an attempt to improve accuracy in performability evaluation, assumptions made have been minimised and a series of computations have been performed for open queuing networks with breakdowns, repairs, and finite queuing capacity. Results obtained from the analytical model are presented comparatively with simulation results and IPP modelling.