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Intrusion detection in mobile ad hoc networksSun, Bo 29 August 2005 (has links)
Most existent protocols, applications and services for Mobile Ad Hoc NET-works (MANETs) assume a cooperative and friendly network environment and do not accommodate security. Therefore, Intrusion Detection Systems (IDSs), serving as the second line of defense for information systems, are indispensable for MANETs with high security requirements. Central to the research described in this dissertation is the proposed two-level nonoverlapping Zone-Based Intrusion Detection System (ZBIDS) which fit the unique requirement of MANETs. First, in the low-level of ZBIDS, I propose an intrusion detection agent model and present a Markov Chain based anomaly detection algorithm. Local and trusted communication activities such as routing table related features are periodically selected and formatted with minimum errors from raw data. A Markov Chain based normal profile is then constructed to capture the temporal dependency among network activities and accommodate the dynamic nature of raw data. A local detection model aggregating abnormal behaviors is constructed to reflect recent subject activities in order to achieve low false positive ratio and high detection ratio. A set of criteria to tune parameters is developed and the performance trade-off is discussed. Second, I present a nonoverlapping Zone-based framework to manage locally generated alerts from a wider area. An alert data model conformed to the Intrusion Detection Message Exchange Format (IDMEF) is presented to suit the needs of MANETs. Furthermore, an aggregation algorithm utilizing attribute similarity from alert messages is proposed to integrate security related information from a wider area. In this way, the gateway nodes of ZBIDS can reduce false positive ratio, improve detection ratio, and present more diagnostic information about the attack. Third, MANET IDSs need to consider mobility impact and adjust their behavior dynamically. I first demonstrate that nodes?? moving speed, a commonly used parameter in tuning IDS performance, is not an effective metric for the performance measurement of MANET IDSs. A new feature -link change rate -is then proposed as a unified metric for local MANET IDSs to adaptively select normal profiles . Different mobility models are utilized to evaluate the performance of the adaptive mechanisms.
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Design and analysis of distributed primitives for mobile ad hoc networksChen, Yu 30 October 2006 (has links)
This dissertation focuses on the design and analysis of distributed primitives for
mobile ad hoc networks, in which mobile hosts are free to move arbitrarily. Arbitrary
mobility adds unpredictability to the topology changes experienced by the network, which
poses a serious challenge for the design and analysis of reliable protocols. In this work,
three different approaches are used to handle mobility. The first part of the dissertation
employs the simple technique of ignoring the mobility and showing a lower bound for the
static case, which also holds in the mobile case. In particular, a lower bound on the worstcase
running time of a previously known token circulation algorithm is proved. In the
second part of the dissertation, a self-stabilizing mutual exclusion algorithm is proposed
for mobile ad hoc networks, which is based on dynamic virtual rings formed by circulating
tokens. The difficulties resulting from mobility are dealt with in the analysis by showing
which properties hold for several kinds of mobile behavior; in particular, it is shown that
mutual exclusion always holds and different levels of progress hold depending on how
the mobility affects the token circulation. The third part of the dissertation presents two
broadcasting protocols which propagate a message from a source node to all of the nodes in
the network. Instead of relying on the frequently changing topology, the protocols depend
on a less frequently changing and more stable characteristic â the distribution of mobile
hosts. Constraints on distribution and mobility of mobile nodes are given which guarantee
that all the nodes receive the broadcast data.
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Trusted application centric ad hoc networkXu, Gang, January 2008 (has links)
Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Computer Science." Includes bibliographical references (p. 113-121).
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Modeling and performance analysis for mobile group localization and formationDenson, D. Paul. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on June 27, 2009). Includes bibliographical references (p. 59-60).
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Congestion control for networks in challenged environmentsZhang, Guohua. January 2008 (has links)
Thesis (Ph.D.) -- University of Texas at Arlington, 2008.
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Remote Monitoring of Residential Energy UsageTramel, Nathan, Dill, Jacob, Almuqallad, Hussam 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / A substantial amount of the energy usage in developed countries is consumed by climate control of residential and commercial structures. Collecting information on the usage patterns of heating, ventilation and air conditioning (HVAC) systems can allow a consumer to better understand the cost and effectiveness of these systems, and allow landlords and others to monitor their use. This paper describes a system which can easily be retrofitted onto legacy HVAC systems to monitor their activity, and then transmit the information over a wireless radio network for archiving and analysis
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Device Pairing Using Visible Light CommunicationsGuo, Shangyuan January 2014 (has links)
Device authentication in ad hoc networks is becoming more and more important. Nowadays, there are many interesting applications which communicate via the short-rang wireless communication channel (such as Bluetooth or WiFi). In the communication, a great deal of sensitive information is required to be transmitted. Therefore, device authentication is significant. In order to build a secure authentication mechanism, protocols are proposed using human control visual channels. However, this method brings many challenges, the main one being the burden placed on humans. Therefore, in this thesis, these protocols are optimized using visible light communication techniques, which significantly reduce the work faced by humans.
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Video Streaming in Vehicular Ad Hoc Networks: Challenges, Protocols and The Use of RedundancyRezende, Cristiano 30 April 2014 (has links)
Vehicular Ad Hoc Networks (VANETs) are no longer a futuristic promise but rather an attainable technology. Vehicles are already equipped with a variety of computational devices that control or assist drivers in many tasks such as localization, safely breaking, parking and passengers entertainment. The majority of services envisioned for VANETs either require the provision of multimedia support or have it as an extremely beneficial additional feature. In particular, video streaming capabilities over VANETs are crucial to the development of interesting and valuable services. However,VANETs’ highly dynamic topology poses as a demanding challenge to the fulfillment of video streaming’s stringent requirements.
The main goal on this thesis is the development of feasible solutions that support the streaming of video content over VANETs. Initially, the main issues of VANETs are explained through both a discussion of its characteristics and the results of some preliminary conclusions. Based on this understanding of VANETs’ peculiarities, three distinguishing solutions are designed REACT-DIS, REDEC and VIRTUS; the two first for video dissemination and the later for video unicast. These solutions offer a great advancement towards the provision of video streaming capabilities but packet loss is still an issue at high data rates.
In order to improve the delivery ratios reached by the previous solutions, redundancy is used as an error correction mechanism. The use of redundancy is ideal for VANETs in handling packet loss as they do not require any interaction between source and receivers nodes. Sophisticated coding techniques were used for an efficient use of the increase on entropy of the information sent by the source node. It was also evaluated the selective use of redundancy solely on packets carrying the crucial information of I-frames. Although this selective approach obtained lower overall delivery ratios than when redundancy is used for all packets, the video quality obtained similar improvements under a much lower cost. The evaluation on the use of redundancy has considered the impact on the rate by which unique video content is received at end-users which is fundamental to understand
the resolution of videos that can be displayed.
This thesis provides several contributions as it advances the knowledge in the peculiarities of VANETs, solutions for video streaming over VANETs and the use of redundancy as an error correction mechanism for video streaming over VANETs.
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Performance enhancement in VANET with admission control and contention window adjustmentTiwari, Vivek 10 September 2012 (has links)
Vehicular Ad Hoc Networks (VANET), a derivative of mobile networks, has the
capability to increase the safety, e ciency and comfort of transportation systems,
and provide users on-the-road Internet connectivity. Because of its impetus and
signi cance in practical scenarios, it becomes a sought after topic in both industry and
academia. In this thesis, we focus on the vehicle-to-infrastructure (V2I) drive-thru
Internet services in a highway scenario. The road side unit (RSU) along a highway
can provide network services for vehicles within the coverage. To enhance the network
performance, we propose two strategies. First, to ensure a high network throughput,
the RSU uses an admission control strategy to limit the competition among vehicles,
and avoid the waste of channel time to the low-data-rate users. Second, based on
the vehicle density, we also propose a contention window (CW) adjustment strategy
which can reduce the collision probability when the network is congested, and reduce
the idle time otherwise. Extensive simulations using network simulator (NS-2) are
given, which demonstrate the e ectiveness of the proposed solutions. / Graduate
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Multi-retransmission Route Discovery Schemes for Ad Hoc Wireless Network with a Realistic Physical LayerJin, Xiangyang 28 September 2011 (has links)
During the route discovery process, each node receiving the route request packet (RReq) will retransmit it exactly once. A distant neighbor may accidentally receive/loose the only RReq and use it to announce a new route, although that link is inferior/superior for route reply packets (RRep) or actual message routing. Overall, the constructed route may be far from the optimal. All existing route discovery schemes (including DSR/AODV) apply retransmission during route discovery exactly once (1R). Based on a realistic physical layer model, we propose two new route discovery schemes: n-retransmission (nR, retransmitting exactly n times) and n-retransmission c-reception (ncRR), retransmitting until we either reach a total of n own retransmissions or c copies from neighbors are heard. We compare our two new scheme with the traditional one, under otherwise identical conditions (same metric, same packet reception probability on each link) and the same choices about possibly retransmitting again upon discovering a better route (R+) or discarding it (R1), generating route reply packet for every received RRep (B*), or for first and better discovered routes only (B2), and retransmitting RRep exactly once (A1), up to a maximum of three times (A3), or optimally u times decided by link quality (Au). Experimental results show that the proposed ncRR scheme (for n=2 and c=3 or c=4) achieves the best tradeoff between quality of route, success rate and message overhead in the route discovery process, followed by the nR scheme, and both of them are superior to the existing traditional schemes.
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