Quality of Service (QoS) is a tool to measure the efficiency of the Ad-hoc network. QoS is a complex function because it depends mainly on four factors (throughput, packet delivery ratio, end-to-end delay and jitter)....Quality of Service (QoS) is a tool to measure the efficiency of the Ad-hoc network. QoS is a complex function because it depends mainly on four factors (throughput, packet delivery ratio, end-to-end delay and jitter). These four factors are functions of internal factors and are variables with the time. In the result the QoS is an ambiguous tool. This paper proposes a brand-new method to solve this ambiguity, it will use the fuzzy technique to simplify the QoS factor and summarize it in a simple form or in a single value for each application. So it will summarize all factors of the QoS in a single value for the network if the applications share is defined. This paper will apply the propose method on Mobile Ad-hoc NETwork (MANET) with different protocols. The new algorithm will summarize the efficiency of each protocol in a single (crisp) value for all applications. Finally, an important conclusion is proved, by experimental result, implying that higher throughput does not usually mean high QoS supported by the protocols.展开更多
We propose a mobility assisted spectrum aware routing(MASAR) protocol for cognitive radio ad hoc networks(CRAHNs),providing robustness to primary user activity and node mobility.This protocol allows nodes to collect s...We propose a mobility assisted spectrum aware routing(MASAR) protocol for cognitive radio ad hoc networks(CRAHNs),providing robustness to primary user activity and node mobility.This protocol allows nodes to collect spectrum information during a spectrum management interval followed by a transmission period.Cognitive users discover next hops based on the collected spectrum and mobility information.Using a beaconless mechanism,nodes obtain the mobility information and spectrum status of their neighbors.A geographical routing scheme is adopted to avoid performance degradation specially due to the mobility of the nodes and the activity of the primary users.Our scheme uses two approaches to fnd either short or stable routes.Since mobility metrics have a signifcant role in the selection of the next hop,both approaches use a reactive mobility update process assisted by mobility prediction to avoid location errors.MASAR protocol performance is investigated through simulations of diferent scenarios and compared with that of the most similar protocol,CAODV.The results indicate that MASAR can achieve signifcant reduction in control overhead as well as improved packet delivery in highly mobile networks.展开更多
文摘Quality of Service (QoS) is a tool to measure the efficiency of the Ad-hoc network. QoS is a complex function because it depends mainly on four factors (throughput, packet delivery ratio, end-to-end delay and jitter). These four factors are functions of internal factors and are variables with the time. In the result the QoS is an ambiguous tool. This paper proposes a brand-new method to solve this ambiguity, it will use the fuzzy technique to simplify the QoS factor and summarize it in a simple form or in a single value for each application. So it will summarize all factors of the QoS in a single value for the network if the applications share is defined. This paper will apply the propose method on Mobile Ad-hoc NETwork (MANET) with different protocols. The new algorithm will summarize the efficiency of each protocol in a single (crisp) value for all applications. Finally, an important conclusion is proved, by experimental result, implying that higher throughput does not usually mean high QoS supported by the protocols.
基金Project supported by Iran Telecommunication Research Center(ITRC)
文摘We propose a mobility assisted spectrum aware routing(MASAR) protocol for cognitive radio ad hoc networks(CRAHNs),providing robustness to primary user activity and node mobility.This protocol allows nodes to collect spectrum information during a spectrum management interval followed by a transmission period.Cognitive users discover next hops based on the collected spectrum and mobility information.Using a beaconless mechanism,nodes obtain the mobility information and spectrum status of their neighbors.A geographical routing scheme is adopted to avoid performance degradation specially due to the mobility of the nodes and the activity of the primary users.Our scheme uses two approaches to fnd either short or stable routes.Since mobility metrics have a signifcant role in the selection of the next hop,both approaches use a reactive mobility update process assisted by mobility prediction to avoid location errors.MASAR protocol performance is investigated through simulations of diferent scenarios and compared with that of the most similar protocol,CAODV.The results indicate that MASAR can achieve signifcant reduction in control overhead as well as improved packet delivery in highly mobile networks.
