Search results for "IEEE 802.11r-2008"

showing 6 items of 6 documents

Increasing the VoIP Capacity through MAP Overhead Reduction in the IEEE 802.16 OFDMa Systems

2010

One of the main issues with supporting VoIP service over 802.16 networks is the signalling overhead caused by the downlink MAP messages due to frequent transmissions and small packets. To decrease the MAP overhead, the 802.16 standard proposes some mechanisms, such as the compressed MAP and sub-MAPs. In this paper, we show by means of extensive dynamic simulations that sub-MAPs can reduce dramatically the signalling overhead associated with VoIP traffic and significantly improve overall VoIP capacity. At the same time, since sub-MAPs are more sensitive to packet drops, they tend to increase the number of HARQ retransmissions in downlink and transmission delays in the uplink direction.

IEEE 802Voice over IPComputer sciencebusiness.industryNetwork packetComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSReal-time computingHybrid automatic repeat requestData_CODINGANDINFORMATIONTHEORYTransmission (telecommunications)Telecommunications linkOverhead (computing)businessComputer networkIEEE 802.11r-2008
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Analysis of the limitations of WiFi communications managed by the IEEE 802.11 protocol in data transmission in automated power distribution systems

2010

This paper presents a study on the performances of the IEEE 802.11 protocol used in a Medium Voltage networks management system, carried out using a model for the simulation of WiFi chains architectures. The results of the simulations give some practical indications for the use of the IEEE 802.11 protocol also in presence of transmissions characterized by rigid time intervals, for which this protocol is usually not suitable. Finally the whole communications system is presented.

IEEE 802.11EngineeringIEEE 802IEEE 802.11uSettore ING-INF/03 - Telecomunicazionibusiness.industryInter-Access Point ProtocolWiFiComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaIEEE 802.1QEmbedded systemIEEE 802.11g-2003DiagnosticIEEE 802.1XbusinessComputer networkIEEE 802.11sIEEE 802.11r-2008SPEEDAM 2010
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Assessing the effectiveness of IEEE 802.11e in multi-hop mobile network environments

2004

The IEEE 802.11e technology is receiving much interest due to the promising enhancements it offers to wireless local area networks in terms of QoS support. Until now, research has focused on single hop, access point based environments, which are the most common. We review the enhancements proposed in the last IEEE 802.11e draft (version 8.0). We analyze the performance of the IEEE 802.11e protocol on ad-hoc networks (multi-hop) in terms of throughput and end-to-end delay. We also measure the effectiveness for static and fully dynamic networks with a variable number of source stations. Finally, we analyze the performance of IEEE 802.11e when legacy IEEE 802.11 stations (no IEEE 802.11e suppo…

IEEE 802.11uIEEE 802IEEE 802.11w-2009business.industryComputer scienceInter-Access Point ProtocolDistributed computingComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSIEEE 802.11b-1999IEEE 802.1XbusinessIEEE 802.11sComputer networkIEEE 802.11r-2008
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QoS Support for Time-Constrained Multimedia Communications in IEEE 802.11 WLANs: A Performance Evaluation

2005

During the past few years, we have been witnessing the massive deployment of IEEE 802.11 wireless LANs. Even though the widespread deployment of such wireless LANs, many studies are still underway aiming to design and develop simple yet effective QoS mechanisms for supporting time-constrained services over such platforms. In this paper, we first overview five different QoS mechanisms recently introduced in the literature as well as the upcoming IEEE 802.11e (EDCA) standard. We then carry out a comparative performance evaluation of all the QoS mechanisms. We focus our study on the effectiveness of the various QoS mechanisms for supporting time-constrained services.

IEEE 802.11uIEEE 802IEEE 802.11w-2009business.industryInter-Access Point ProtocolComputer scienceComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSWireless Multimedia ExtensionsMobile QoSIEEE 802.11e-2005businessTelecommunicationsComputer networkIEEE 802.11r-20082005 Systems Communications (ICW'05, ICHSN'05, ICMCS'05, SENET'05)
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An energy analysis of IEEE 802.15.6 scheduled access modes

2010

Body Area Networks (BANs) are an emerging area of wireless personal communications. The IEEE 802.15.6 working group aims to develop a communications standard optimised for low power devices operating on, in or around the human body. IEEE 802.15.6 specifically targets low power medical application areas. The IEEE 802.15.6 draft defines two main channel access modes; contention based and contention free. This paper examines the energy lifetime performance of contention free access and in particular of periodic scheduled allocations. This paper presents an overview of the IEEE 802.15.6 and an analytical model for estimating the device lifetime. The analysis determines the maximum device lifeti…

Settore ING-INF/03 - TelecomunicazioniComputer scienceInter-Access Point Protocolbusiness.industryPhysical layerbiomedical communication body area networks personal area networksIEEE 802.15.6 scheduled access modes body area network channel access modes communications standard device lifetime estimation energy analysis energy lifetime performance human body low power devices low power medical application areas periodic scheduled allocation wireless personal communicationTelecommunications linkBody area networkWirelessIEEE 802.11e-2005TransceiverbusinessIEEE 802.15IEEE 802.11r-2008Computer network2010 IEEE Globecom Workshops
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Achieving Robustness through Caching and Retransmissions in IEEE 802.15.4-based WSNs

2007

This paper proposes a network-layer protocol for wireless sensor networks based on the IEEE 802.15.4 standard. Our protocol is devised to provide reliable data gathering in latency-constrained applications, and exploits both the flexibility of the IEEE 802.15.4 MAC layer and features of data aggregation techniques, such as implicit acknowledgment of reception. The proposed protocol acts as a routing module and a control entity for the MAC layer and provides reliable communication, while managing power saving and synchronizertion among nodes. Without relying on MAC-layer acknowledgments, the protocol implements caching and network-layer retransmissions, triggered upon detection of a link fai…

Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniComputer scienceInter-Access Point Protocolbusiness.industryComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSEnergy consumptionNetwork allocation vectorWireless sensor networksIEEE 802.1QLogical link controlbusinessWireless sensor networkIEEE 802.15IEEE 802.11r-2008Computer networkIEEE 802.11s2007 16th International Conference on Computer Communications and Networks
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