Comparative cost-benefit analysis of two reliability models for one unit base transceiver system considering hardware based software faults

Abstract

This paper deals with comparative analysis of two stochastic models for a base transceiver system given in [5] and [6] to judge which and when one model is better than the other in terms of different measures of system performance and costs. A base transceiver system may fail or may not work satisfactorily on occurrence of some major or minor faults, common cause failures or network traffic congestion. When major/minor fault occurs the repair team first inspects whether there is hardware or software or hardware based software fault then recovery of the relevant component is done. In the first model given in [5], only hardware and software failures are taken whereas in the model given in [6], hardware based software failures and common cause failures are taken apart from considering occurrence of some minor or major faults in hardware/ software components and traffic congestion. In these models it is assumed that the minor fault leads to partial failure or degradation state whereas a major fault and common cause failure leads to complete failure of the system. On the basis of computed measures of system performance, comparison of the models with respect to their mean times to failures, expected uptimes/degradation times and profits is made using graphs for some particular case and conclusions are drawn.