Khalid Alnowibet* and Lotfi Tadj
This paper analyzes an MX/G/1 queueing system where the server is subject to random breakdowns and the server applies the D-policy in providing the service. The steady-state queue size probability distribution is obtained using the embedded Markov chain technique. Key performance measures of the system are derived to obtain the optimal value of the threshold level D that minimizes the expected total cost per unit of time. The theoretical results are verified by special cases with published formulas.