This paper addresses a shortcoming of the widely used Generalized Processor Sharing (GPS) scheduling a1 U rithm which can have significant impact on the pmviied service, however; which has been given little attention. Since, with GPS, the service rate received by a session is proportional to the number of backlogged sessions in the system, the service rate of a session may change abruptly if so...

This paper is dedicated to the study of HARQ protocols under a secrecy constraint. An encoder sends information to a legitimate decoder while keeping it secret from the eavesdropper. Our objective is to provide a coding scheme that satisfies both reliability and confidentiality conditions. This problem has been investigated in the literature using a coding scheme that involves a unique secrecy ...

Legacy 802.11b/g protocols have been successfully applied in wireless long-distance (WiLD) networks to provide low-cost network connectivity for rural areas and developing countries, by designing TDMA MAC protocols. In contrast, we investigate the performance, and enhancement of using 802.11n for WiLD networks still using CSMA/CA. Our extensive experiments from our testbed show that, although 8...

Minstrel is a practical rate selection algorithm for commodity 802.11 radios, implemented in the Linux kernel and the ns-3 network simulator. Design of a rate selection mechanism is complicated by the variety of sources of packet loss in 802.11 networks, the difficulty of testing rate adaptation, and interaction with higher layer protocols (especially TCP). Minstrel is based solely on acknowled...

Adaptation often involves the acquisition of a large number of genomic changes that arise as mutations in single individuals. In asexual populations, combinations of mutations can fix only when they arise in the same lineage, but for populations in which genetic information is exchanged, beneficial mutations can arise in different individuals and be combined later. In large populations, when th...

Explanations of the evolution of diploidy have focused on the advantages gained from masking deleterious alleles. Recent theory has shown, however, that masking does not always provide an advantage to diploidy and would never favor diploidy in predominantly asexual organisms. We explore a neglected alternative theory which posits that, by doubling the genome size, diploids double the rate at wh...

This paper investigates secure transmission using HARQ protocol when the encoder only knows the statistics of the channel-state. We analyze the tradeoff between reliability and secrecy probabilistic guarantees. The conventional approach of ensuring the secrecy via introduction of dummy-message is followed. However, unlike the previous works on this subject, we design a coding strategy tailored ...

Mobile computing environments that seek to support communication-intensive applications need to provide sustained end-to-end networking resources to static and mobile ows in the presence of scarce and variable wireless bandwidth, bursty wireless channel error, and user mobility. In order to achieve this goal, we present the design and implementation of a new resource management architecture and...

We present enhancements to the TCP-Friendly Rate Control mechanism (TFRC) designed to better handle the intermittent connectivity occurring in mobility situations. Our aim is to quickly adapt to new network conditions and better support real-time applications for which the user-perceived quality depends on the immediate transmission rate. We propose to suspend the transmission before disconnect...

A rate adaptation buuer is used in communications networks at the interface between two consecutive links, when the speed of the incoming link exceeds the speed of the outgoing link, in order to avoid excessive cell loss. In this paper we examine the performance of such a buuer in the case that the ratio between the input rate and the output rate takes an integer value, as well as in the more g...