802.11b Throughput with Link Interference

IEEE 802.11 MAC is a CSMA/CA protocol and uses RTS/CTS exchanges to avoid the hidden terminal problem. Recent findings have revealed that the carriersensing range set in current major implementations does not detect and prevent all interference signals even using RTS/CTS access method together. In this paper, we investigate the effect of interference and develop a mathematical model for it. We demonstrate that the 802.11 DCF does not properly act on the interference channel due to the small size and the exponential increment of backoff windows. The accuracy of our model is verified via simulations. Based on an insight from our model, we present a simple protocol that operates on the top of 802.11 MAC layer and achieves more throughput than rate-adjustment schemes

Asymptotic bounds for M^X/G/1 processor sharing queues

This paper analyzed the asymptotic bounds of an M/G/1 processor sharing queue with bulk arrivals

Review of Data Mining Techniques for Churn Prediction in Telecom

Telecommunication sector generates a huge amount of data due to increasing number of subscribers, rapidly renewable technologies; data based applications and other value added service. This data can be usefully mined for churn analysis and prediction. Significant research had been undertaken by researchers worldwide to understand the data mining practices that can be used for predicting customer churn. This paper provides a review of around 100 recent journal articles starting from year 2000 to present the various data mining techniques used in multiple customer based churn models. It then summarizes the existing telecom literature by highlighting the sample size used, churn variables employed and the findings of different DM techniques. Finally, we list the most popular techniques for churn prediction in telecom as decision trees, regression analysis and clustering, thereby providing a roadmap to new researchers to build upon novel churn management models

Review of Data Mining Techniques for Churn Prediction in Telecom

Telecommunication sector generates a huge amount of data due to increasing number of subscribers, rapidly renewable technologies; data based applications and other value added service. This data can be usefully mined for churn analysis and prediction. Significant research had been undertaken by researchers worldwide to understand the data mining practices that can be used for predicting customer churn. This paper provides a review of around 100 recent journal articles starting from year 2000 to present the various data mining techniques used in multiple customer based churn models. It then summarizes the existing telecom literature by highlighting the sample size used, churn variables employed and the findings of different DM techniques. Finally, we list the most popular techniques for churn prediction in telecom as decision trees, regression analysis and clustering, thereby providing a roadmap to new researchers to build upon novel churn management models

The Public Option: a Non-regulatory Alternative to Network Neutrality

Network neutrality and the role of regulation on the Internet have been heavily debated in recent times. Amongst the various definitions of network neutrality, we focus on the one which prohibits paid prioritization of content and we present an analytical treatment of the topic. We develop a model of the Internet ecosystem in terms of three primary players: consumers, ISPs and content providers. Our analysis looks at this issue from the point of view of the consumer, and we describe the desired state of the system as one which maximizes consumer surplus. By analyzing different scenarios of monopoly and competition, we obtain different conclusions on the desirability of regulation. We also introduce the notion of a Public Option ISP, an ISP that carries traffic in a network neutral manner. Our major findings are (i) in a monopolistic scenario, network neutral regulations benefit consumers; however, the introduction of a Public Option ISP is even better for consumers, as it aligns the interests of the monopolistic ISP with the consumer surplus and (ii) in an oligopolistic situation, the presence of a Public Option ISP is again preferable to network neutral regulations, although the presence of competing price-discriminating ISPs provides the most desirable situation for the consumers

PBS: A Unified Priority-Based CPU Scheduler

A novel CPU scheduling policy is designed and implemented. It is a configurable policy in the sense that a tunable parameter is provided to change its behavior. With different settings of the parameter, this policy can emulate the first-come first-serve, the processing sharing, or the feedback policies, as well as different levels of their mixtures. This policy is implemented in the Linux kernel as a replacement of the default scheduler. The drastic changes of behaviors as the parameter changes are analyzed and simulated. Its performance is measured with the real systems by the workload generators and benchmarks