The increasing use of computers for saving valuable data imposes stringent reliability constraints on storage systems. Reliability improvement via use of redundancy is a common practice. As the disk capacity improves, advanced techniques such as disk scrubbing are being employed to proactively fix latent sector errors. These techniques utilize the disk idle time for reliability improvement. How...

The utilization of idle compute cycles has been known as most promising and cost-effective way to build a large scale high performance computing system, but not widely used because of the lack of effective idleness prediction techniques. In this paper, we argue PCs at university computer labs have a great potential for the utilization of idle CPU cycles, and propose two techniques for predictin...

spend much of their time idle, and various schemes have been proposed to use this idle time productively. We have used this approach to improve overall performance in storage systems. The most common approach is to off-load activity from busy periods to less-busy ones in order to improve system responsiveness. In addition, speculative work can be performed in idle periods in the hope that it wi...

We model and analyze the distributed task allocation problem, which is solved by ant colonies on a daily basis. Ant colonies employ task allocation in which ants are moved from one task to the other in order to meet changing demands introduced by the environment, such as excess or shortage of food, dirtier or cleaner nest, etc. The different tasks are: nursing (overseeing the hatching of newbie...

In cognitive radio networks (CRNs), secondary users (SUs) may employ network coding to pursue higher throughput. However, as SUs must vacate the spectrum when it is accessed by primary users (PUs), the available transmission time of SUs is usually uncertain, i.e., SUs do not know how long the idle state can last. Meanwhile, existing network coding strategies generally adopt a block-based transm...

ABSTRACT IEEE 802.16 WiMAX is a promising technology to provide broadband wireless networking access. IEEE 802.16j Mobile Multihop Relay standard introduces multihop relaying to WiMAX system. Relay stations are used to extended network coverage and enhance system throughput. To reduce power consumption, an idle mode MS does not send location update messages while moving across cell borders. Pag...

Despite a low occurrence rate, silent data corruption represents a growing concern for storage systems designers. Throughout the storage hierarchy, from the file system down to the disk drives, various solutions exist to avoid, detect, and correct silent data corruption. Undetected errors during the completion of WRITEs may cause silent data corruption. A portion of the WRITE errors may be dete...

We deviate from the Berman et al. models in inventory with positive service time. We establish a necessary and sufficient condition for system stability. Several performance measures are computed. An optimisation problem is discussed. Our analysis suggests that it is optimal to place the replenishment order when the inventory level is positive (even in the zero lead time case). Numerical illust...

Chocs and-calculus are two extensions of CCS where, respectively, processes and channels are transmissible values. In previous work we have proposed a formalization of the notion of bisimulation for Chocs. In this paper we suggest a more eeective way to reason about this notion by means of an embedding of Chocs into a richer calculus endowed with a notion ofàctivation' channel which we christen...

Port scans are done by an attacker to discover which services are o ered by systems on a network and could be attacked. There are various approaches for port scanning, all providing advantages and disadvantages. One of those approaches is the TCP Idle Scan, in which the attacker spoofs messages of a third computer in order to remain undetected. To see the results of the scan, he utilizes the IP...