60,688 research outputs found

    Source Delay in Mobile Ad Hoc Networks

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    Source delay, the time a packet experiences in its source node, serves as a fundamental quantity for delay performance analysis in networks. However, the source delay performance in highly dynamic mobile ad hoc networks (MANETs) is still largely unknown by now. This paper studies the source delay in MANETs based on a general packet dispatching scheme with dispatch limit ff (PD-ff for short), where a same packet will be dispatched out up to ff times by its source node such that packet dispatching process can be flexibly controlled through a proper setting of ff. We first apply the Quasi-Birth-and-Death (QBD) theory to develop a theoretical framework to capture the complex packet dispatching process in PD-ff MANETs. With the help of the theoretical framework, we then derive the cumulative distribution function as well as mean and variance of the source delay in such networks. Finally, extensive simulation and theoretical results are provided to validate our source delay analysis and illustrate how source delay in MANETs are related to network parameters.Comment: 11page

    Underwater spray and wait routing technique for mobile ad-hoc networks

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    1648-1655The underwater mobile ad-hoc networks comprise sensor nodes that are source nodes for gathering underwater-related data. Relay nodes are the mobile nodes for collecting data from sensor nodes and achieving intermittent connectivity among source and destination nodes. Developing an efficient routing protocol for underwater communication is a challenging issue due to limitations of the underwater environment. Underwater mobile ad-hoc networks are intermittent networks where end-to-end path does not exist from source to destination. To overcome these problems a delay and disruption tolerant network (DTN) is a good solution. In the current paper, we consider the Spray and Wait (SaW) routing technique. In SaW, source and relay nodes represents the moving nodes, and they try to send data to destination nodes. Based on this, we propose the replica based underwater SaW (USaW) routing for underwater mobile ad-hoc networks. In USaW, source nodes are fixed to the bottom of the surface. Underwater sensor nodes replicate sensor data and provide maximum copies of data to the relay nodes that they encounter. In generally, relay nodes have high capability of transmitting data as compared to sensor nodes in an underwater environment. We analyze the performance of USaW with respect to delivery ratio, network throughput, energy consumption, end-to-end delay, and packet drop rate comparing with existing SaW and prophet routing protocols

    Improving Ad Hoc Networks Capacity and Connectivity Using Dynamic Blind Beamforming

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    We propose a dynamic blind beamforming scheme which allows to benefit from antenna directivity in large mobile ad hoc networks while avoiding heavy feedback to track mobile nodes localization. By orienting its directional antenna successively in all directions, a source surely but blindly hits its destination without knowing its exact position. Performance is analyzed in terms of total network throughput and connectivity and the optimal number of rotations allowing to maximize performance is shown to result from a trade-off between delay and improvements in terms of interference. In large ad hoc networks, known to be interference limited, we show that dynamic blind beamforming can outperform omnidirectional transmissions both in terms of capacity and connectivit

    Analysis and Modeling Experiment Performance Parameters of Routing Protocols in MANETs and VANETs

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    In this paper, a framework for experimental parameters in which Packet Delivery Ratio (PDR), effect of link duration over End-to-End Delay (E2ED) and Normalized Routing Overhead (NRO) in terms of control packets is analyzed and modeled for Mobile Ad-Hoc NETworks (MANETs) and Vehicular Ad-Hoc NETworks (VANETs) with the assumption that nodes (vehicles) are sparsely moving in two different road. Moreover, this paper contributes the performance comparison of one Proactive Routing Protocol; Destination Sequenced Distance vector (DSDV) and two reactive protocols; DYnamic Source Routing (DSR) and DYnamic MANET On-Demand (DYMO). A novel contribution of this work is enhancements in default versions of selected routing protocols. Three performance parameters; PDR, E2ED and NRO with varying scalabilities are measured to analyze the performance of selected routing protocols with their original and enhanced versions. From extensive simulations, it is observed that DSR outperforms among all three protocols at the cost of delay. NS-2 simulator is used for simulation with TwoRayGround propagation model to evaluate analytical results

    A Study of Congestion Aware Adaptive Routing Protocols in MANET

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    Routing protocols for mobile ad hoc networks (MANETs) have been explored extensively in last few years. Much of this work is targeted at finding a feasible route from a source to a destination without considering current network traffic or application requirements. Routing may let a congestion happen which is detected by congestion control, but dealing with congestion in reactive manner results in longer delay, and unnecessary packet loss and requires significant overhead if a new route is needed. Routing should not be aware of, but also be adaptive to, network congestion. Adaptation to the congestion helps to increase both the effectiveness and efficiency of routing. These problems are solved by the congestion-aware routing protocols in certain degree. These protocols which are adaptive to congestion status of mobile ad-hoc network can greatly improve the network performance. In this paper, we present the survey of congestion adaptive routing protocols for mobile ad-hoc network. Finally, the future direction of congestion-aware routing protocols is described. Keywords: Ad hoc networks, congestion aware routing, Congestion metric, congestion adaptabilit

    A Survey of MANET Routing Protocols in Large-Scale and Ordinary Networks

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    An ad hoc network (MANET) consists of mobile nodes that communicate with each other. Routing in ad hoc network is a challenging task because nodes are mobile. Efficient routing protocols have better performance in such networks. Many protocols have been proposed for ad hoc networks such as: Ad hoc on-demand Distance Vector (AODV), Optimized Link State Routing (OLSR), Dynamic Source Routing (DSR), and Geographic routing protocol (GRP). these approaches have not been evaluated for the same conditions in pervious researches. But in this study, the performance of these protocols is evaluated in various network conditions and with different packet size patterns. Also, different MAC layers like 802.11b, 802.11g in ordinary and large-scale networks are considered. For the evaluation, Different metrics like packet delivery ratio, end-to-end delay, Mac delay and Routing traffic received/sent, are applied. All simulations have been done using OPNET

    P-AODV Routing Protocol for Better Performance in MANET

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    MANET (Mobile Ad-Hoc Network) is an independent collection of mobile nodes that communicate over quite bandwidth constrained wireless links. In Mobile Ad hoc Networks (MANETs), the performance of various on-demand routing protocols significantly affected by the changing network topology.in the route discovery process, AODV (Ad-hoc On-Demand Distance Vector) is the mostly studied on-demand routing protocol that uses single route reply packet with reverse path for answering to the source node. Due to increase in the variability of the network topology, the possibility of route reply packet loss increases & destroys the performance of the routing protocol. It includes related material and details of other modified AODV protocols like R-AODV, Multipath Routing Protocol. This protocols makes better performance as compared to AODV but there we need more modification for efficient. We then focus on the end-to-end delay, throughput and overhead for the performance improvement. As by, we proposed a new AODV routing protocol that uses R-AODV for route discovery and Multipath routing protocol for data(packet) sending from source to the destination. Our proposed Protocol (P-AODV) would improve performance in terms of Average End-to-End Delay, Throughput and Routing Overhead. DOI: 10.17762/ijritcc2321-8169.15058
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