Contemporary networks accommodate handling of multiple priorities, aiming to provide suitable QoS levels to different traffic classes. In the presence of multiple priorities, a scheduling algorithm is employed to select each time the next packet to transmit over the data link. Class-based Weighted Fair Queuing (CBWFQ) scheduling and its variations, is widely used as a scheduling technique, sinc...

This paper is concerned with the stability of a preemptive repeat priority queueing system with multiple types of customers and customer transfers between queues. Using the mean-drift method and matrix-analytic methods, simple conditions for the queueing system to be stable or instable are found. The conditions indicate that system stability depends only on the service rate of customers of the ...

We obtain an essentially optimal tradeoff between the amortized cost of the three basic priority queue operations insert, delete and find-min in the comparison model. More specifically, we show that A(find-min) = Ω ( n (2 + )A(insert)+A(delete) )

We study MX/G/1 nonpreemptive and preemptive-resume priority queues with/without vacations under random order of service (ROS) discipline within each class. By considering the conditional waiting times given the states of the system, which an arbitrary message observes upon arrival, we derive the Laplace-Stieltjes transforms of the waiting time distributions and explicitly obtain the first two ...

A new priority queue structure is introduced, for which the amortized time to insert a new element isO(1) while that for the minimumextraction is O(logK). K is the average, taken over all the deleted elements x, of the number of elements that are inserted during the lifespan of x and are still in the heap when x is removed. Several applications of our structure are mentioned.

A Bernoulli schedule is random service discipline for a multi-class priority queueing system which operates as follows: If queue i(l :s i :s N) is not empty just after servicing a message in its queue, a message in queue i is served again with probability Pi, and the highest class message present in the system is served with probability 1-Pi, where 0 :s Pi :s 1. This paper presents an analysis ...

AbstmctA direct application of commonly used synchronization primitives such as semaphores, monitors, or the Ada rendezvous can lead to uncontrolled priority inversion, a situation in which a higher priority job is blocked by lower priority jobs for an indefinite period of time. In this paper, we investigate two protocols belonging to the class of priority inheritance protocols, called the basi...

The ability to perform traffic differentiation is a promising feature of the current Medium Access Control (MAC) in Wireless Local Area Networks (WLANs). The Enhaced Distributed Channel Access (EDCA) MAC protocol for WLANs proposes up to four Access Categories (AC) that can be mapped to different traffic priorities. High priority ACs are allowed to transmit more often than low priority ACs, pro...

The hierarchical smoothed round robin (HSRR) packet scheduler that improves the performance of the smoothed round robin (SRR) for real-world packet scheduling scenarios is presented. The SRR suffers from an inability to fairly distribute service in highly skewed weight distributions where such distributions often occur in practice. As a result, the transmission behaviour of the SRR can be burst...