4,223 research outputs found

    Na neizrazitoj logici zasnovano upravljanje frekvencijom za ODMRP u mobilnim ad hoc mrežama

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    On Demand Multicast Routing Protocol (ODMRP) is a popular solution designed for ad hoc networks with mobile hosts. Its efficiency, simplicity, and robustness to mobility render it one of the most widely used multicast routing protocols in Mobile Ad hoc NETworks (MANET). In ODMRP, there is no input rate control for upper layer traffic. So, it’s possible that high dense traffic flow causes congestion in networks. In this work, an enhancement to ODMRP is proposed referred to as fuzzy logic based Rate Control ODMRP (FRC-ODMRP). FRC-ODMRP attempts to adapt the arrival rate from upper layers to the state in the network by using feedback information from receivers of the multicast group. Accordingly, source comes up with a decision whether to increase or decrease its transmission rate based on information collected from the receivers. In this research, delay and packet delivery ratio reconsidered as indicators of congestion in addition to number of received packets. Simulation results demonstrate that FRC-ODMRP achieves significant performance improvements in comparison to conventional ODMRP and QoS-ODMRP. Indeed, it efficiently handles simultaneous traffic flows such that no one could dominate available bandwidth of networks.On Demand Multicast Routing Protocol (ODMRP) popularno je rješenje namijenjeno ad hoc mrežama s mobilnim domaćinima. Efikasnost, jednostavnost i robusnost u smislu mobilnosti učini su ovu metodu jednom od najraširenijih multicast protokola u ad hoc mobilnim mrežam (eng. MANET). Kod ODMRP-a nema upravljanja ulaznom frekvencijom za promet višeg sloja. Zbog toga je moguće da gusti promet uzrokuje zagušenje u mrežama. U ovome je radu predstavljeno poboljšanje ODMRP-a nazvano ODMRP zasnovan na fuzzy logici (FRC-ODRMP). FRC-ODRMP pokušava prilagoditi dolazne signale iz viših slojeva stanju u mreži koristeći povratnu informaciju od primatelja iz multicast grupe. Prilikom istraživanja dodatno je uzet omjer kašnjenja i dostavljenih paketa kao pokazatelj zagušenosti mreže uz broj dostavljenih paketa. Simulacijski rezultati pokazuju kako FRC-ODMRP značajno poboljšava performanse u odnosu na konvencionalni ODMRP i Qos-ODMRP. Dodatno, simultani promet efikasno je upravljan tako da nitko ne može dominirati dostupnom propusnošću mreže

    A Review of the Energy Efficient and Secure Multicast Routing Protocols for Mobile Ad hoc Networks

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    This paper presents a thorough survey of recent work addressing energy efficient multicast routing protocols and secure multicast routing protocols in Mobile Ad hoc Networks (MANETs). There are so many issues and solutions which witness the need of energy management and security in ad hoc wireless networks. The objective of a multicast routing protocol for MANETs is to support the propagation of data from a sender to all the receivers of a multicast group while trying to use the available bandwidth efficiently in the presence of frequent topology changes. Multicasting can improve the efficiency of the wireless link when sending multiple copies of messages by exploiting the inherent broadcast property of wireless transmission. Secure multicast routing plays a significant role in MANETs. However, offering energy efficient and secure multicast routing is a difficult and challenging task. In recent years, various multicast routing protocols have been proposed for MANETs. These protocols have distinguishing features and use different mechanismsComment: 15 page

    Performance Enhancement of Routing in MANETs by using EOMD

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    Usually large scale of network applications requires communication of the single copy of same information packets simultaneously to many destinations. Applying the infrastructure- based multicast routing protocols in Mobile Ad hoc wireless Networks (MANETs) is a big challenge task. The circumstances that make Multicasting in ad hoc networks is extra intricate than in wired networks are node mobility, Interference of Wi-Fi alerts and broadcast nature of the communication. Tree based Protocols aren't suitable for common topology modifications as an excessive amount of overhead for updating the filter information and additionally no longer suitable for partition or isolation. The major impact of routing for multi-hop MANETs comes due to mobility of the node, as performance is prone to modifications in network topology. When any link breaks, the direction should be repaired or changed, similar to direction preservation or route discovery, respectively. The rerouting process charges in radio bandwidth and battery energy, and the extra routing latency can also affect QoS for community packages, degrading communication performance. The ODMRP is more robust to mobility and unreliable wireless links as its core layout relies on periodic floods of path discovery and renovation. ODMRP periodically reconstructs the ?forwarding mesh? on a fixed quick interval. The path refresh is the most essential parameter because it has the important effect at the protocol overhead. We proposed an Extended - On Demand Multicast Routing Protocol with motion detection (EOMD), which reduces communication overhead and performance improvisation in mobile Ad-Hoc Network in Mobility

    Evaluasi Kinerja Protokol Perutean AODV dan SDGR+R pada VANET dengan Studi Kasus Pelabuhan Lembar

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    The Vehicular ad-hoc Network (VANET) is a subclass of Mobile ad-hoc networks (MANETs).VANET is a wireless network created from the concept of building a vehicle network (node) toexchange data information (data communication). There is a new concept technique forVANET communication used, namely the use of the concept of Software Defined Network(SDN) on VANET. For data communication between vehicles, a routing protocol required. Themost common routing protocol used on VANET since 2003 is AODV. In 2014 several studieswere using the SDN paradigm tried on VANET technology to improve the performance ofQuality of Service (QoS), one of which is a Geographic-based SDN, called SDGR in 2016.Multicast is a method of routing data on a network that allows one node or a group of nodes tocommunicate efficiently with the receiving node. The multicast concept supports one-to-manyrouting in nodes that send packet data to a group of nodes. The development of the SDGRrouting protocol using the idea of multicast technique to SDGR based on the Direction calledSDGR + R carried out in 2019. This study uses a case study of vehicle transportationsimulations in the Lamber Port area of Lombok. The simulation results knew that SDGR + Ris better than AODV in terms of service quality (QoS) at a latency of 15.58% and packet deliveryratio (PDR) of 47.78%

    Mengenal pasti masalah pemahaman dan hubungannya dengan latar belakang matematik, gaya pembelajaran, motivasi dan minat pelajar terhadap bab pengawalan kos makanan di Sekolah Menengah Teknik (ert) Rembau: satu kajian kes.

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    Kajian ini dijalankan untuk mengkaji hubungan korelasi antara latar belakang Matematik, gaya pembelajaran, motivasi dan minat dengan pemahaman pelajar terhadap bab tersebut. Responden adalah seramai 30 orang iaitu terdiri daripada pelajar tingkatan lima kursus Katering, Sekolah Menengah Teknik (ERT) Rembau, Negeri Sembilan. Instrumen kajian adalah soal selidik dan semua data dianalisis menggunakan program SPSS versi 10.0 untuk mendapatkan nilai min dan nilai korelasi bagi memenuhi objektif yang telah ditetapkan. Hasil kajian ini menunjukkan bahawa hubungan korelasi antara gaya pembelajaran pelajar terhadap pemahaman pelajar adalah kuat. Manakala hubungan korelasi antara latar belakang Matematik, motivasi dan minat terhadap pemahaman pelajar adalah sederhana. Nilai tahap min bagi masalah pemahaman pelajar, latar belakang Matematik, gaya pembelajaran, motivasi dan minat terhadap bab Pengawalan Kos Makanan adalah sederhana. Kajian ini mencadangkan penghasilan satu Modul Pembelajaran Kendiri bagi bab Pengawalan Kos Makanan untuk membantu pelajar kursus Katering dalam proses pembelajaran mereka

    Security and Privacy Issues in Wireless Mesh Networks: A Survey

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    This book chapter identifies various security threats in wireless mesh network (WMN). Keeping in mind the critical requirement of security and user privacy in WMNs, this chapter provides a comprehensive overview of various possible attacks on different layers of the communication protocol stack for WMNs and their corresponding defense mechanisms. First, it identifies the security vulnerabilities in the physical, link, network, transport, application layers. Furthermore, various possible attacks on the key management protocols, user authentication and access control protocols, and user privacy preservation protocols are presented. After enumerating various possible attacks, the chapter provides a detailed discussion on various existing security mechanisms and protocols to defend against and wherever possible prevent the possible attacks. Comparative analyses are also presented on the security schemes with regards to the cryptographic schemes used, key management strategies deployed, use of any trusted third party, computation and communication overhead involved etc. The chapter then presents a brief discussion on various trust management approaches for WMNs since trust and reputation-based schemes are increasingly becoming popular for enforcing security in wireless networks. A number of open problems in security and privacy issues for WMNs are subsequently discussed before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the author's previous submission in arXiv submission: arXiv:1102.1226. There are some text overlaps with the previous submissio
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