72,136 research outputs found

    HWN* Mobility Management Considering QoS, Optimisation and Cross Layer Issues

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    In this paper, we address mobility management for 4th generation heterogeneous networks from a quality of service (QoS), optimisation and cross layer design perspective. Users are classified as high profile, normal profile and low profile according to their differentiated service requirements. Congestion avoidance control and adaptive handover mechanisms are implemented for efficient cooperation within the mobile heterogeneous network environment consisting of a TDMA network, ad hoc network and relay nodes. A previous proposed routing algorithm is also revised to include mobility management

    Reliable multicast in heterogeneous mobile ad-hoc networks

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    In disaster scenarios, communication infrastructure could be damaged or completely failed. Mobile Ad-hoc Networks (MANETs) can be used to substitute failed communication devices and thus to enable communication. As group communication is an important part in disaster scenarios, multicast will be used to address several nodes. In this paper, we propose our new reliable multicast protocol RMDA (Reliable Multicast over Delay Tolerant Mobile Ad hoc Networks). We introduce an efficient group management approach and a new method for reliable multicast delivery over Delay Tolerant Networks. We show, that our protocol is adaptive to different kinds of MANETs, e.g. with or without clusterheads, respectively. For those without, we use our name resolution over adaptive routing approach

    Towards End-to-End QoS in Ad Hoc Networks

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    http://citi.insa-lyon.fr/wons2006/index.htmlIn this paper, we address the problem of supporting adaptive QoS resource management in mobile ad hoc networks, by proposing an efficient model for providing proportional endto- end QoS between classes. The effectiveness of our proposed solution in meeting desired QoS differentiation at a specific node and from end-to-end are assessed by simulation using a queueing network model implemented in QNAP. The experiments results show that the proposed solution provides consistent proportional differentiation for any service class and validates our claim even under bursty traffic and fading channel conditions

    An identity-based broadcast encryption scheme for mobile ad hoc networks, Journal of Telecommunications and Information Technology, 2006, nr 1

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    Dynamic ad hoc networks facilitate interconnections between mobile devices without the support of any network infrastructure. In this paper, we propose a secure identity-based ad hoc protocol for mobile devices to construct a group key for a setup of a secure communication network in an efficient way and support dynamic changing of network topology. Unlike group key management protocols proposed previously in the literature, mobile devices can use our protocol to construct the group key by observing the others’ identity, like the MAC address, which distinguishes the device from the others. In contrast to other interactive protocols, we only need one broadcast to setup the group key and member removal is also highly efficient. Finally, we discuss the security issues and provide security proofs for our protocol

    A Dynamic Application Partitioning and Offloading Framework to Enhance the Capabilities of Transient Clouds Using Mobile Agents

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    Mobile cloud computing has emerged as a prominent area of research, a natural extension of cloud computing that proposes to offer solutions for enhancing the capabilities of smart mobile devices commonly plagued by resource constraints. As one of its promising models, transient clouds aim to address the internet connectivity shortfall inherent in most solutions through the formation of ad hoc networks by devices in close proximity, then the offloading some computations (Cyber Foraging) to the created cloud. However, transient clouds, at their current state, have several limitations, concerning their expansion on a local network having a large number of devices and the management of the instability of the network due to the constant mobility of the devices. Another issue is the fact code partitioning and offloading are not addressed to fit the need of such networks, thereby rendering the distributed computing mechanism barely efficient for the Transient Cloud. In this study, we propose a transient cloud-based framework that exploits the use of multi-agent systems, enabling a dynamic partitioning and offloading of code, and facilitating the movement and the execution of code partition packets in a multi-hop ad-hoc mesh network. When created and deployed, these intelligent mobile agents operate independently or collaboratively and adapt to the continual entry and exit of devices in the neighbourhood. The integration of these trending concepts in distributed computing within a framework offers a new architecture for resource-sharing among cooperating devices that addresses the varied issues that arise in dynamic environments

    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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