Search results for "Distributed coordination function"

showing 4 items of 14 documents

Rethinking the IEEE 802.11e EDCA Performance Modeling Methodology

2010

Analytical modeling of the 802.11e enhanced distributed channel access (EDCA) mechanism is today a fairly mature research area, considering the very large number of papers that have appeared in the literature. However, most work in this area models the EDCA operation through per-slot statistics, namely probability of transmission and collisions referred to "slots." In so doing, they still share a methodology originally proposed for the 802.11 Distributed Coordination Function (DCF), although they do extend it by considering differentiated transmission/ collision probabilities over different slots.We aim to show that it is possible to devise 802.11e models that do not rely on per-slot statis…

IEEE 802medium access protocolSettore ING-INF/03 - TelecomunicazioniComputer Networks and Communicationsbusiness.industryComputer scienceWiFiDistributed computingQuality of serviceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSQoSThroughputDistributed coordination functionComputer Science ApplicationsTransmission (telecommunications)Wireless lanElectrical and Electronic EngineeringbusinessThroughput (business)SoftwareComputer networkCommunication channelIEEE/ACM Transactions on Networking
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MAC design on real 802.11 devices: From exponential to Moderated Backoff

2016

In this paper we describe how a novel backoff mechanism called Moderated Backoff (MB), recently proposed as a standard extension for 802.11 networks, has been prototyped and experimentally validated on a commercial 802.11 card before being ratified. Indeed, for performance reasons, the time critical operations of MAC protocols, such as the backoff mechanism, are implemented into the card hardware/firmware and cannot be arbitrarily changed by third parties or by manufacturers only for experimental reasons. Our validation has been possible thanks to the availability of the so called Wireless MAC Processor (WMP), a prototype of a novel wireless card architecture in which MAC protocols can be p…

Settore ING-INF/03 - Telecomunicazionibusiness.industryFirmwareWireless ad hoc networkComputer scienceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS05 social sciences050801 communication & media studies020206 networking & telecommunicationsTime critical02 engineering and technologyDistributed coordination functioncomputer.software_genreExponential functionComputer Networks and Communication0508 media and communicationsFormal languageMedia Technology0202 electrical engineering electronic engineering information engineeringWirelessbusinesscomputerComputer network2016 IEEE 17th International Symposium on A World of Wireless, Mobile and Multimedia Networks (WoWMoM)
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Achieving Fair Bandwidth Distribution in WiFi Networks: A Game Theoretical Approach

2011

International audience; Achieving fair bandwidth distribution among uplink and downlink ows in IEEE 802.11 infrastructure networks is a complex issue, due to the well-known features of the Distributed Coordination Function (DCF) which regulates the access to the shared medium. Indeed, the dynamic adaptation of the contention windows causes phenomena of short-term unfairness, while the use of homogeneous contention parameters among the contending nodes makes the aggregated downlink bandwidth equal to the uplink bandwidth of a single node. We propose a dynamic tuning of the contention parameters used by the nodes, based on simple network monitoring functionalities and rational strategies. Spe…

WiFi; game theorygame theoryDynamic bandwidth allocationbusiness.industryComputer scienceDistributed computingWiFiComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSNetwork monitoringShared mediumDistributed coordination functionNash equilibriumShared resource[INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI]Telecommunications linkComputer Science::Networking and Internet ArchitectureBandwidth (computing)NetworksbusinessGame theoryGame theoryComputer network
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Improving IEEE 802.11 Performance in Chain Topologies through Distributed Polling and Network Coding

2009

Wireless multi-hop networks often rely on the use of IEEE 802.11 technology. Despite of the robustness of the IEEE 802.11 Distributed Coordination Function (DCF) for working in various network scenarios, it has been proven that critical inefficiencies can arise in the case of multi-hop packet forwarding. In this paper, we propose a MAC scheme, based on the virtualization of the Point Coordination Function, optimized for working on chain topologies with bidirectional traffic flows. Our scheme is based on a token-like access mechanism coupled with network coding. The basic idea is the use of multiple Point Coordinators (PCs) along the node chain, which are elected by passing special token fra…

business.industryBidirectional trafficComputer scienceSettore ING-INF/03 - TelecomunicazioniDistributed computingComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSPacket forwardingThroughputnetwork codingDistributed coordination functionNetwork topologyWLANToken passingPoint coordination functionIEEE 802.11Linear network codingWireless lanTelecommunications linkComputer Science::Networking and Internet ArchitectureWirelessPollingbusinessComputer network
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