Wireless sensor networks (WSNs) are required to provide different levels of Quality of Services (QoS) based on the type of applications. Providing QoS support in wireless sensor networks is an emerging area of researc...Wireless sensor networks (WSNs) are required to provide different levels of Quality of Services (QoS) based on the type of applications. Providing QoS support in wireless sensor networks is an emerging area of research. Due to resource constraints like processing power, memory, bandwidth and power sources in sensor networks, QoS support in WSNs is a challenging task. In this paper, we discuss the QoS requirements in WSNs and present a survey of some of the QoS aware routing techniques in WSNs. We also explore the middleware approaches for QoS support in WSNs and finally, highlight some open issues and future direction of research for providing QoS in WSNs.展开更多
To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater...To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater environment.Moreover,the underwater acoustic channels are affected by hindrances such as long propagation delay and limited bandwidth,which appear in the design of the MAC protocol for the UWSNs.The available MAC protocols for the terrestrial wireless sensor networks exhibit low performance in energy efficiency,throughput and reliability in the UWSNs,and cannot be used in the UWSNs directly because of their unique characteristics.This paper proposes a synchronous duty-cycled reservation-based MAC protocol named Ordered Contention MAC(OCMAC)protocol.The basic mechanism of this protocol is to schedule data transmission by transmitters through the scheduling of Ready To Send(RTS)frames.The protocol eliminates the possible collision during data transmission and improves communication efficiency.The paper analyzes the performance in energy efficiency,throughput and reliability of the protocol by modeling the queuing behavior of OCMAC with a Markov Chain process.Furthermore,the analytical model is validated through a simulation study.The analysis results demonstrated that while providing good throughput and reliability,OCMAC can achieve energy saving.展开更多
Quality of Service (QoS) in Wireless Sensor Networks (WSNs) is a challenging area of research because of the limited availability of resources in WSNs. The resources in WSNs are processing power, memory, bandwidth, en...Quality of Service (QoS) in Wireless Sensor Networks (WSNs) is a challenging area of research because of the limited availability of resources in WSNs. The resources in WSNs are processing power, memory, bandwidth, energy, communication capacity, etc. Delay is an important QoS parameter for delivery of delay sensitive data in a time constraint sensor network environment. In this paper, an extended version of a delay aware routing protocol for WSNs is presented along with its performance comparison with different deployment scenarios of sensor nodes, taking IEEE802.15.4 as the underlying MAC protocol. The performance evaluation of the protocol is done by simulation using ns-2 simulator.展开更多
文摘Wireless sensor networks (WSNs) are required to provide different levels of Quality of Services (QoS) based on the type of applications. Providing QoS support in wireless sensor networks is an emerging area of research. Due to resource constraints like processing power, memory, bandwidth and power sources in sensor networks, QoS support in WSNs is a challenging task. In this paper, we discuss the QoS requirements in WSNs and present a survey of some of the QoS aware routing techniques in WSNs. We also explore the middleware approaches for QoS support in WSNs and finally, highlight some open issues and future direction of research for providing QoS in WSNs.
文摘To design an energy-efficient Medium Access Control(MAC)protocol for the Underwater Wireless Sensor Networks(UWSNs)is an urgent research issue since depleted batteries cannot be recharged or replaced in the underwater environment.Moreover,the underwater acoustic channels are affected by hindrances such as long propagation delay and limited bandwidth,which appear in the design of the MAC protocol for the UWSNs.The available MAC protocols for the terrestrial wireless sensor networks exhibit low performance in energy efficiency,throughput and reliability in the UWSNs,and cannot be used in the UWSNs directly because of their unique characteristics.This paper proposes a synchronous duty-cycled reservation-based MAC protocol named Ordered Contention MAC(OCMAC)protocol.The basic mechanism of this protocol is to schedule data transmission by transmitters through the scheduling of Ready To Send(RTS)frames.The protocol eliminates the possible collision during data transmission and improves communication efficiency.The paper analyzes the performance in energy efficiency,throughput and reliability of the protocol by modeling the queuing behavior of OCMAC with a Markov Chain process.Furthermore,the analytical model is validated through a simulation study.The analysis results demonstrated that while providing good throughput and reliability,OCMAC can achieve energy saving.
文摘Quality of Service (QoS) in Wireless Sensor Networks (WSNs) is a challenging area of research because of the limited availability of resources in WSNs. The resources in WSNs are processing power, memory, bandwidth, energy, communication capacity, etc. Delay is an important QoS parameter for delivery of delay sensitive data in a time constraint sensor network environment. In this paper, an extended version of a delay aware routing protocol for WSNs is presented along with its performance comparison with different deployment scenarios of sensor nodes, taking IEEE802.15.4 as the underlying MAC protocol. The performance evaluation of the protocol is done by simulation using ns-2 simulator.
