Performance analysis of the retrial queueing systems
Sprache der Bezeichnung:
Englisch
Original Kurzfassung:
Retrial queues are important stochastic models for many telecommunication systems. In order to
construct competitive networks it is necessary to investigate problems related to optimal control of
queueing systems. In this paper we analyse a controlled retrial queue with two exponential
heterogeneous servers in which the time between two successive repeated attempts is independent of
the number of customers applying for the service. The customers upon arrival are queued in the orbit
or enters service area according to the control policy. This system is analyzed as controlled quasibirth-
and-death (QBD) process. It is showed that the optimal control policy is of threshold and
monotone type. We propose the value iteration algorithm for the calculation of optimal threshold levels
and perform the steady-state analysis using matrix-geometric approach. The main performance
characteristics are calculated for the system under optimal threshold policy (OTP) and compared with
the same characteristics for the model under scheduling threshold policy (STP) and other heuristic
policies, e.g. the usage of the Fastest Free Server (FFS) or Random Server Selection (RSS).