Composite performance and dependability analysis is gaining importance in the design of complex, fault-tolerant systems. Markov reward models are most commonly used for this purpose. In this paper, an introduction to Markov reward models including solution techniques and application examples is presented. Extensions of Markov reward models to semi-Markov reward models are also mentioned. A brief discussion of how task completion time models and models of queues with breakdowns and repairs relate to Markov reward models is also given.

No abstract

No abstract

This chapter addresses the issue of determining the response time distribution in networks of queues. Four different techniques are described and demonstrated. A two-step numerical approach to compute the response time distribution for closed Markovian networks with general connectivity, a technique for determining the approximate (exact under certain conditions) response time distribution of a time Markov chain (CTMC) "response time blocks," an expansion of "response time blocks" to open Markovian networks with general phase-type (PH) service time distributions, and an approach for handling non-Markovian networks having M/G/1 priority and PH/G/1 queues. These techniques are shown to give accurate results with much smaller CTMCs or semi-Markov processes than exact analysis.

No abstract