41,565 research outputs found

    Heterogeneous Networking: An Enabling Paradigm for Ubiquitous Wireless Communications

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    In this paper we explore the principle of heterogeneous wireless networking and discuss the potential avenues towards the realization of the ubiquitous wireless communications. Specifically, we demonstrate that the heterogeneous network architecture, constituted by the fusion of the classic cellular and the ad hoc network topologies, inherits the vital complementary characteristics of both architectures, and thus has the potential of attaining the levels of performance and efficiency required by the future wireless communications

    DISTRIBUTED INTELLIGENT SPECTRUM MANAGEMENT IN COGNITIVE RADIO AD HOC NETWORKS

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    The rapid growth of the number of wireless devices has brought an exponential increase in the demand of the radio spectrum. However, according to the Federal Communications Commission (FCC), almost all the radio spectrum for wireless com- munications has already been allocated. In addition, according to FCC, up to 85% of the allocated spectrum is underutilized due to the current fixed spectrum alloca- tion policy. To alleviate the spectrum scarcity problem, FCC has suggested a new paradigm for dynamically accessing the allocated spectrum. Cognitive radio (CR) technology has emerged as a promising solution to realize dynamic spectrum access (DSA). With the capability of sensing the frequency bands in a time and location- varying spectrum environment and adjusting the operating parameters based on the sensing outcome, CR technology allows an unlicensed user to exploit the licensed channels which are not used by licensed users in an opportunistic manner. In this dissertation, distributed intelligent spectrum management in CR ad hoc networks is explored. In particular, four spectrum management issues in CR ad hoc networks are investigated: 1) distributed broadcasting in CR ad hoc networks; 2) distributed optimal HELLO message exchange in CR ad hoc networks; 3) distributed protocol to defend a particular network security attack in CR ad hoc networks; and 4) distributed spectrum handoff protocol in CR ad hoc networks. The research in this dissertation has fundamental impact on CR ad hoc network establishment, net- work functionality, network security, and network performance. In addition, many of the unique challenges of distributed intelligent spectrum management in CR ad hoc networks are addressed for the first time in this dissertation. These challenges are extremely difficult to solve due to the dynamic spectrum environment and they have significant effects on network functionality and performance. This dissertation is essential for establishing a CR ad hoc network and realizing networking protocols for seamless communications in CR ad hoc networks. Furthermore, this dissertation provides critical theoretical insights for future designs in CR ad hoc networks

    User Needs and Advances in Space Wireless Sensing and Communications

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    Decades of space exploration and technology trends for future missions show the need for new approaches in space/planetary sensor networks, observatories, internetworking, and communications/data delivery to Earth. The User Needs to be discussed in this talk includes interviews with several scientists and reviews of mission concepts for the next generation of sensors, observatories, and planetary surface missions. These observatories, sensors are envisioned to operate in extreme environments, with advanced autonomy, whereby sometimes communication to Earth is intermittent and delayed. These sensor nodes require software defined networking capabilities in order to learn and adapt to the environment, collect science data, internetwork, and communicate. Also, some user cases require the level of intelligence to manage network functions (either as a host), mobility, security, and interface data to the physical radio/optical layer. For instance, on a planetary surface, autonomous sensor nodes would create their own ad-hoc network, with some nodes handling communication capabilities between the wireless sensor networks and orbiting relay satellites. A section of this talk will cover the advances in space communication and internetworking to support future space missions. NASA's Space Communications and Navigation (SCaN) program continues to evolve with the development of optical communication, a new vision of the integrated network architecture with more capabilities, and the adoption of CCSDS space internetworking protocols. Advances in wireless communications hardware and electronics have enabled software defined networking (DVB-S2, VCM, ACM, DTN, Ad hoc, etc.) protocols for improved wireless communication and network management. Developing technologies to fulfil these user needs for wireless communications and adoption of standardized communication/internetworking protocols will be a huge benefit to future planetary missions, space observatories, and manned missions to other planets

    TelosRFID an ad-hoc wireless networking capable multi-protocol RFID reader system

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    Radio Frequency IDentification (RFID) is rapidly being adopted as a powerful tool used in object tracking access control, telemedicine and inventory management. Its basic architecture endows reader devices with the capability to wirelessly read stored data off of RFID tags. Because of competing standards, there is no unified air protocol for RFID communication. The proliferation of competing standards, paired with the proprietary nature of commercial readers, can make maintaining and upgrading an RFID infrastructure expensive and time-consuming. Part of the solution that this thesis proposes is an RFID reader which supports custom air protocol implementations. To further reduce the costs associated with the adoption of a new infrastructure, RFID readers would benefit from supporting ad-hoc wireless networking. This feature mitigates the need for an installed infrastructure and facilitates immediate deployment of RFID systems. The development of a multi-protocol RFID reader with ad-hoc wireless capabilities will be a boon for both the commercial and academic sectors. This thesis outlines the design of an ad-hoc wireless networking capable multi-protocol RFID reader system called TelosRFID. The name TelosRFID stems from the system\u27s combination of Crossbow Telos rev. B (TelosB) ZigBee motes with a custom 13.56MHz RFID reader board. The TelosRFID reader board is a custom hardware device that can communicate with 13.56MHz RFID tags. It runs custom firmware in order to control tag communications, manage tag presence monitoring, and relay tag information through the ZigBee network (via its attached TelosB mote.) The system is designed to be demonstratably useful. Its functionality can be visibly confirmed, and configuration errors are easily detected at every component in the system. This framework provides a reliable and established baseline for future enhancements to the system\u27s feature set

    Spontaneous ad hoc mobile cloud computing network

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    Cloud computing helps users and companies to share computing resources instead of having local servers or personal devices to handle the applications. Smart devices are becoming one of the main information processing devices. Their computing features are reaching levels that let them create a mobile cloud computing network. But sometimes they are not able to create it and collaborate actively in the cloud because it is difficult for them to build easily a spontaneous network and configure its parameters. For this reason, in this paper, we are going to present the design and deployment of a spontaneous ad hoc mobile cloud computing network. In order to perform it, we have developed a trusted algorithm that is able to manage the activity of the nodes when they join and leave the network. The paper shows the network procedures and classes that have been designed. Our simulation results using Castalia show that our proposal presents a good efficiency and network performance even by using high number of nodes.Lacuesta, R.; Lloret, J.; Sendra, S.; Peñalver Herrero, ML. (2014). Spontaneous ad hoc mobile cloud computing network. Scientific World Journal. 2014:1-19. doi:10.1155/2014/232419S1192014Rodrigues, J. J. P. C., Zhou, L., Mendes, L. D. P., Lin, K., & Lloret, J. (2012). Distributed media-aware flow scheduling in cloud computing environment. Computer Communications, 35(15), 1819-1827. doi:10.1016/j.comcom.2012.03.004Feeney, L. M., Ahlgren, B., & Westerlund, A. (2001). Spontaneous networking: an application oriented approach to ad hoc networking. IEEE Communications Magazine, 39(6), 176-181. doi:10.1109/35.925687Fernando, N., Loke, S. W., & Rahayu, W. (2013). Mobile cloud computing: A survey. Future Generation Computer Systems, 29(1), 84-106. doi:10.1016/j.future.2012.05.023Lacuesta, R., Lloret, J., Garcia, M., & Peñalver, L. (2013). A Secure Protocol for Spontaneous Wireless Ad Hoc Networks Creation. IEEE Transactions on Parallel and Distributed Systems, 24(4), 629-641. doi:10.1109/tpds.2012.168Lacuesta, R., Lloret, J., Garcia, M., & Peñalver, L. (2011). Two secure and energy-saving spontaneous ad-hoc protocol for wireless mesh client networks. Journal of Network and Computer Applications, 34(2), 492-505. doi:10.1016/j.jnca.2010.03.024Lacuesta, R., Lloret, J., Garcia, M., & Peñalver, L. (2010). A Spontaneous Ad Hoc Network to Share WWW Access. EURASIP Journal on Wireless Communications and Networking, 2010(1). doi:10.1155/2010/232083Lacuesta, R., Palacios-Navarro, G., Cetina, C., Peñalver, L., & Lloret, J. (2012). Internet of things: where to be is to trust. EURASIP Journal on Wireless Communications and Networking, 2012(1). doi:10.1186/1687-1499-2012-203Capkun, S., Buttyan, L., & Hubaux, J. (2003). Self-organized public-key management for mobile ad hoc networks. IEEE Transactions on Mobile Computing, 2(1), 52-64. doi:10.1109/tmc.2003.1195151Goodman, J., & Chandrakasan, A. (2000). An Energy Efficient Reconfigurable Public-Key Cryptography Processor Architecture. Lecture Notes in Computer Science, 175-190. doi:10.1007/3-540-44499-8_13Mayrhofer, R., Ortner, F., Ferscha, A., & Hechinger, M. (2003). Securing Passive Objects in Mobile Ad-Hoc Peer-to-Peer Networks. Electronic Notes in Theoretical Computer Science, 85(3), 105-121. doi:10.1016/s1571-0661(04)80687-xMendes, L. D. P., Rodrigues, J. J. P. C., Lloret, J., & Sendra, S. (2014). Cross-Layer Dynamic Admission Control for Cloud-Based Multimedia Sensor Networks. IEEE Systems Journal, 8(1), 235-246. doi:10.1109/jsyst.2013.2260653Dutta, R., & B, A. (2014). Protection of data in unsecured public cloud environment with open, vulnerable networks using threshold-based secret sharing. Network Protocols and Algorithms, 6(1), 58. doi:10.5296/npa.v6i1.486

    Optimisation of Bluetooth wireless personal area networks

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    In recent years there has been a marked growth in the use of wireless cellular telephones, PCs and the Internet. This proliferation of information technology has hastened the advent of wireless networks which aim to increase the accessibility and reach of communications devices. Ambient Intelligence (Ami) is a vision of the future of computing in which all kinds of everyday objects will contain intelligence. To be effective, Ami requires Ubiquitous Computing and Communication, the latter being enabled by wireless networking. The IEEE's 802.11 task group has developed a series of radio based replacements for the familiar wired ethernet LAN. At the same time another IEEE standards task group, 802.15, together with a number of industry consortia, has introduced a new level of wireless networking based upon short range, ad-hoc connections. Currently, the most significant of these new Wireless Personal Area Network (WPAN) standards is Bluetooth, one of the first of the enabling technologies of Ami to be commercially available. Bluetooth operates in the internationally unlicensed Industrial, Scientific and Medical (ISM) band at 2.4 GHz. unfortunately, this spectrum is particularly crowded. It is also used by: WiFi (IEEE 802.11); a new WPAN standard called Zig- Bee; many types of simple devices such as garage door openers; and is polluted by unintentional radiators. The success of a radio specification for ubiquitous wireless communications is, therefore, dependant upon a robust tolerance to high levels of electromagnetic noise. This thesis addresses the optimisation of low power WPANs in this context, with particular reference to the physical layer radio specification of the Bluetooth system

    Adoption of vehicular ad hoc networking protocols by networked robots

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    This paper focuses on the utilization of wireless networking in the robotics domain. Many researchers have already equipped their robots with wireless communication capabilities, stimulated by the observation that multi-robot systems tend to have several advantages over their single-robot counterparts. Typically, this integration of wireless communication is tackled in a quite pragmatic manner, only a few authors presented novel Robotic Ad Hoc Network (RANET) protocols that were designed specifically with robotic use cases in mind. This is in sharp contrast with the domain of vehicular ad hoc networks (VANET). This observation is the starting point of this paper. If the results of previous efforts focusing on VANET protocols could be reused in the RANET domain, this could lead to rapid progress in the field of networked robots. To investigate this possibility, this paper provides a thorough overview of the related work in the domain of robotic and vehicular ad hoc networks. Based on this information, an exhaustive list of requirements is defined for both types. It is concluded that the most significant difference lies in the fact that VANET protocols are oriented towards low throughput messaging, while RANET protocols have to support high throughput media streaming as well. Although not always with equal importance, all other defined requirements are valid for both protocols. This leads to the conclusion that cross-fertilization between them is an appealing approach for future RANET research. To support such developments, this paper concludes with the definition of an appropriate working plan

    An Overview of Mobile Ad Hoc Networks for the Existing Protocols and Applications

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    Mobile Ad Hoc Network (MANET) is a collection of two or more devices or nodes or terminals with wireless communications and networking capability that communicate with each other without the aid of any centralized administrator also the wireless nodes that can dynamically form a network to exchange information without using any existing fixed network infrastructure. And it's an autonomous system in which mobile hosts connected by wireless links are free to be dynamically and some time act as routers at the same time, and we discuss in this paper the distinct characteristics of traditional wired networks, including network configuration may change at any time, there is no direction or limit the movement and so on, and thus needed a new optional path Agreement (Routing Protocol) to identify nodes for these actions communicate with each other path, An ideal choice way the agreement should not only be able to find the right path, and the Ad Hoc Network must be able to adapt to changing network of this type at any time. and we talk in details in this paper all the information of Mobile Ad Hoc Network which include the History of ad hoc, wireless ad hoc, wireless mobile approaches and types of mobile ad Hoc networks, and then we present more than 13 types of the routing Ad Hoc Networks protocols have been proposed. In this paper, the more representative of routing protocols, analysis of individual characteristics and advantages and disadvantages to collate and compare, and present the all applications or the Possible Service of Ad Hoc Networks.Comment: 24 Pages, JGraph-Hoc Journa
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