Data automata on data words is a decidable model proposed by Bojańczyk et al. in 2006. Class automata, introduced recently by Bojańczyk and Lasota, is an extension of data automata which unifies different automata models on data words. The nonemptiness of class automata is undecidable, since class automata can simulate two-counter machines. In this paper, a decidable model called class automata...

Content delivery providers can improve their service scalability and offload their servers by making use of content transfers among their clients. To provide peers with incentive to transfer data to other peers, protocols such as BitTorrent typically employ a tit-for-tat policy in which peers give upload preference to peers that provide the highest upload rate to them. However, the tit-for-tat ...

Two traditional approaches exist for a task that is blocked on a global resource; a task either performs a non-preemptive busy wait, i.e., spins, or suspends and releases the processor. Previously, we have shown that both approaches can be viewed as spinning either at the highest priority (HP) or at the lowest priority on the processor (LP), respectively. Based on this view, previously we have ...

In this paper we present the approximate waiting time analysis of two class non-preemptive priority queues. The traffics of the queue are characterized by ”two parameter description”, which means that the mean and the squared coefficient of variation of the inter arrival times and of the service times are given. The solution is based on the separate analysis of the low and high priority queue. ...

The classical M / G / l system with vacations has been used to estimate the mean waiting t ime of individual priority classes of homogeneous FDDI networks. To faithfully model the FDDI network using M / G / l system, the vacation interval of the server (token) as seen by individual priority classes must be evaluated. The expressions for the mean waiting time of individual priority classes are f...

Accountable decision-makers are required to legitimize their priority setting decisions in health to members of society. In this perspective we stress the point that fair, legitimate processes should reflect efforts of authorities to treat all stakeholders as moral equals in terms of providing all people with well-justified, reasonable reasons to endorse the decisions. ...

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...