2 research outputs found

    Dynamic routing discovery scheme for high mobility in mobile ad hoc wireless networks

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    An innovative technology that is widely used in many applications is the Mobile Ad-hoc Network (MANET). Discovery and maintenance of routes at MANET are important issues. Within MANET, broadcasting is used to discover a path within on-demand routing protocols. Establishing and maintaining a route periodically among the nodes is the challenge that requires the transmitting of control packets across a network. This state leads to the issue of broadcasting storms. Broadcasting control packets increase control packets overhead and decrease network performance. In this paper, we proposed a scheme called AODV-Velocity and Dynamic (AODV-VD) for effective broadcast control packets. The routing protocol for the ad-hoc on-demand distance victor (AODV) is used to implement the proposed AODV-VD scheme. AODV-VD scheme reduces both the excessive route discovery control packets and network overhead. Network simulator version 2.35 (NS2.35) was used to compare the proposed AODV-VD scheme to the AODV routing protocol in terms of end-to-end latency, average throughput, packet transmission ratio and overhead ratio

    Error control in bacterial quorum communications

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    Quorum sensing (QS) is used to describe the communication between bacterial cells, whereby a coordinated population response is controlled through the synthesis, accumulation and subsequent sensing of specific diffusible chemical signals called autoinducers, enabling a cluster of bacteria to regulate gene expression and behavior collectively and synchronously, and assess their own population. As a promising method of molecular communication (MC), bacterial populations can be programmed as bio-transceivers to establish information transmission using molecules. In this work, to investigate the key features for MC, a bacterial QS system is introduced, which contains two clusters of bacteria, specifically Vibrio fischeri, as the transmitter node and receiver node, and the diffusive channel. The transmitted information is represented by the concentration of autoinducers with on-off keying (OOK) modulation. In addition, to achieve better reliability and energy efficiency, different error control techniques, including forward error correction (FEC) and Automatic Repeat reQuest (ARQ) are taken into consideration. For FEC, this work presents a comparison of the performance of traditional Hamming codes, Minimum Energy Codes (MEC) and Luby Transform (LT) codes over the channel. In addition, it applied several ARQ protocols, namely Stop-N-Wait (SW-ARQ), Go-Back-N (GBN-ARQ), and Selective-Repeat (SR-ARQ) combined with error detection codes to achieve better reliability. Results show that both the FEC and ARQ techniques can enhance the channel reliability, and that ARQ can resolve the issue of out-of-sequence and duplicate packet delivery. Moreover, this work further addresses the question of optimal frame size for data communication in this channel capacity and energy constrained bacterial quorum communication system. A novel energy model which is constructed using the experimental validated synthetic logic gates has been proposed to help with the optimization process. The optimal fixed frame length is determined for a set of channel parameters by maximizing the throughput and energy efficiency matrix
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