We consider a discrete-time queueing system subjected to random server interruptions. As customers arriving in the queue require generally distributed service times, the server can be interrupted during a customer’s service. Therefore, nine different service strategies are proposed and analyzed using a probability generating functions approach. Performance measures under investigation include m...

This paper compares two discrete-time single-server queueing models with queues. In both models, the server is available to a queue probability 1/2 at each service opportunity. Since obtaining easy-to-evaluate expressions for joint moments not feasible, we rely on heavy-traffic limit approach. The correlation coefficient of queue-contents computed via solution two-dimensional functional equatio...

In this paper, we consider a queue whose service speed changes according to an external environment that is governed by a Markov process. It is possible that the server changes its service speed many times while serving a customer. We derive first and second moments of the service time of customers in system using first step analysis to obtain an insight on the service process. In fact, we obta...

Proposals to improve the performance of TCP in high speed networks have been recently put forward. Examples of such proposals include High-Speed TCP, Scalable TCP, and FAST. In contrast to the additive increase multiplicative decrease algorithm used in the standard TCP, Scalable TCP uses a multiplicative increase multiplicative decrease (MIMD) algorithm for the window size evolution. In this pa...

this paper presents a discrete-time single-server finite buffer n threshold policy queue with renewal input and discretemarkovian service process. the server terminates service whenever the system becomes empty, and recommencesservice as soon as the number of waiting customers in the queue is n. we obtain the system-length distributionsat pre-arrival and arbitrary epochs using the supplementary...

One of the key performance measures in queueing systems is the exponential decay rate of the steady-state tail probabilities of the queue lengths. It is known that if a corresponding fluid model is stable and the stochastic primitives have finite moments, then the queue lengths also have finite moments, so that the tail probability P(· > s) decays faster than s−n for any n. It is natural to con...