End to end QoS (Quality of Service) is crucial in computer networks, but very hard to study as the systems are in general very complex. We suppose that systems can be modeled by multidimensional Markov processes, which could be very hard to analyse if there is no specific solution form. We propose to apply stochastic comparisons of Markov processes in order to solve this problem. We provide new...

This paper presents a general framework for optimal task reallocation in heterogeneous distributed computing systems (DCSs). The framework relies on a rigorous analytical model for the stochastic execution time of a workload. The model takes into account the heterogeneity and randomness of both service times and communication delays, an arbitrary task-reallocation policy as well as the stochast...

It is well known that in stochastic service systems such as telecommunications networks, selective denial of service based on system state can enhance performance. For example, in a cellular mobile network, preference might be given to hando calls over new calls when the system is more heavily loaded. When the service center can be modeled as a markov process, there exist means to calculate the...

With cloud computing growing in popularity cloud-service providers must guarantee that data are processed rapidly and transferred when and where they are needed. Unfortunately, it is extremely difficult to predict the exact performance characteristics and demands on the network at any particular time. In this paper we show that the cloud computing demand can be developed as a branching stochast...

Resource allocation for cloud services is a complex task due to the diversity of the services and the dynamic workloads. One way to address this is by overprovisioning which results in high cost due to the unutilized resources. A much more economical approach, relying on the stochastic nature of the demand, is to allocate just the right amount of resources and use additional more expensive mech...

In most production-inventory systems, the products are transferred from the production centre to the inventory (warehouse) in subbatchs rather than one at a time. In this paper, mathematical models of such systems for both deterministic and stochastic cases of demand are developed and analysed. Comparison of these new models with the EBQ model shows a considerable loss when applying the ru...