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299
Delay and Capacity Trade-offs in Mobile Ad Hoc Networks: A Global Perspective
, 2007
"... ... which showed that mobility can increase the capacity of an ad hoc network, there has been a lot of interest in characterizing the delay-capacity relationship in ad hoc networks. Various mobility models have been studied in the literature, and the delay-capacity relationships under those models h ..."
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Cited by 145 (2 self)
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... which showed that mobility can increase the capacity of an ad hoc network, there has been a lot of interest in characterizing the delay-capacity relationship in ad hoc networks. Various mobility models have been studied in the literature, and the delay-capacity relationships under those models have been characterized. The results indicate that there are trade-offs between the delay and capacity, and that the nature of these trade-offs is strongly influenced by the choice of the mobility model. Some questions that arise are: (i) How representative are these mobility models studied in the literature? (ii) Can the delay-capacity relationship be significantly different under some other “reasonable” mobility model? (iii) What sort of delay-capacity trade-off are we likely to see in a real world scenario? In this paper, we take the first step toward answering these questions. In particular, we analyze, among others, the mobility models studied in recent related works, under a unified framework. We relate the nature of delay-capacity trade-off to the nature of node motion, thereby providing a better understanding of the delay-capacity relationship in ad hoc networks in comparison to earlier works.
Access and Mobility of Wireless PDA Users
"... In this paper, we analyze the mobility patterns of users of wireless handheld PDAs in a campus wireless network using an 11 week trace of wireless network activity. Our study has three goals. First, we characterize the high-level mobility and access patterns of handheld PDA users and compare these c ..."
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Cited by 142 (4 self)
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In this paper, we analyze the mobility patterns of users of wireless handheld PDAs in a campus wireless network using an 11 week trace of wireless network activity. Our study has three goals. First, we characterize the high-level mobility and access patterns of handheld PDA users and compare these characteristics to previous workload mobility studies focused on laptop users. Second, we develop two wireless network topology models for use in wireless mobility studies: an evolutionary topology model based on user proximity and a campus waypoint model that serves as a trace-based complement to the random waypoint model. Finally, we use our wireless network topology models as a case study to evaluate ad-hoc routing algorithms on the network topologies created by the access and mobility patterns of users of modern wireless PDAs.
The IMPORTANT framework for analyzing the Impact of Mobility on Performance Of RouTing protocols for Adhoc NeTworks
, 2003
"... A Mobile Ad hocNcBV`D (MAN`D is a collection of wireless mobile nodes forming a temporary network without using any existing infrastructure. Since not manyMANB` are currently deployed, research in this area is mostly simulation based. Random Waypoint is the commonly used mobility model in these simu ..."
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Cited by 130 (12 self)
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A Mobile Ad hocNcBV`D (MAN`D is a collection of wireless mobile nodes forming a temporary network without using any existing infrastructure. Since not manyMANB` are currently deployed, research in this area is mostly simulation based. Random Waypoint is the commonly used mobility model in these simulations. Random Waypoint is a simple model that may be applicable to some scenarios. However, we believe that it is not su#cient to capture some important mobility characteristics of scenarios in which MANhB may be deployed. Our framework aims to evaluate the impact of di#erent mobility models on the performance ofMAN; routing protocols. We propose various protocol independent metrics to capture interesting mobility characteristics, including spatial and temporal dependence and geographic restrictions. In addition, a rich set of parameterized mobility models is introduced including Random Waypoint, Group Mobility, Freeway and Manhattan models. Based on these models several #test-suite# scenarios are chosen carefully to span the metric space. We demonstrate the utility of our test-suite by evaluating variousMANo routing protocols, including DSR, AODV and DSDV. Our results show that the protocol performance may vary drastically across mobility models and performance rankings of protocols may vary with the mobility models used. This e#ect can be explained by the interaction of the mobility characteristics with the connectivity graph properties. Finally, we attempt to decompose the reactive routing protocols into mechanistic "building blocks" to gain a deeper insight into the performance variations across protocols in the face of mobility.
Exploiting Mobility for Energy Efficient Data Collection
- in Sensor Networks,‖ Mobile Networks and Applications
, 2006
"... Abstract. We analyze an architecture based on mobility to address the problem of energy efficient data collection in a sensor network. Our approach exploits mobile nodes present in the sensor field as forwarding agents. As a mobile node moves in close proximity to sensors, data is transferred to the ..."
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Cited by 113 (1 self)
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Abstract. We analyze an architecture based on mobility to address the problem of energy efficient data collection in a sensor network. Our approach exploits mobile nodes present in the sensor field as forwarding agents. As a mobile node moves in close proximity to sensors, data is transferred to the mobile node for later depositing at the destination. We present an analytical model to understand the key performance metrics such as data transfer, latency to the destination, and power. Parameters for our model include: sensor buffer size, data generation rate, radio characteristics, and mobility patterns of mobile nodes. Through simulation we verify our model and show that our approach can provide substantial savings in energy as compared to the traditional ad-hoc network approach.
PATHS: Analysis of PATH Duration Statistics and their Impact on Reactive MANET Routing Protocols
- in Proc. of MobiHoc
, 2003
"... We develop a detailed approach to study how mobility impacts the performance of reactive MANET routing protocols. In particular we examine how the statistics of path durations including PDFs vary with the parameters such as the mobility model, relative speed, number of hops, and radio range. We find ..."
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Cited by 78 (4 self)
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We develop a detailed approach to study how mobility impacts the performance of reactive MANET routing protocols. In particular we examine how the statistics of path durations including PDFs vary with the parameters such as the mobility model, relative speed, number of hops, and radio range. We find that at low speeds, certain mobility models may induce multi-modal distributions that reflect the characteristics of the spatial map, mobility constraints and the communicating tra#c pattern. However, our study suggests that at moderate and high velocities the exponential distribution with appropriate parameterizations is a good approximation of the path duration distribution for a range of mobility models. The reciprocal of the average path duration is analytically shown to have a strong linear relationship with the throughput and overhead that is confirmed by the simulation results for DSR.
Energy Environ
- Sci
, 2012
"... approach for robust speech recognition in noisy ..."
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The effect of mobility-induced location errors on geographic routing in ad hoc and sensor networks: Analysis and improvement using mobility prediction
- IEEE Trans. on Mobile Computing
, 2004
"... Abstract- Geographic routing in mobile ad hoc networks has proved to provide drastic performance improvement over strictly address-centric routing schemes. While geographic routing has been shown to be correct and efficient when location information is accurate, its performance in the face of locati ..."
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Cited by 59 (4 self)
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Abstract- Geographic routing in mobile ad hoc networks has proved to provide drastic performance improvement over strictly address-centric routing schemes. While geographic routing has been shown to be correct and efficient when location information is accurate, its performance in the face of location errors is not well understood. In this paper, we study the effect of inaccurate location information caused by node mobility under a rich set of scenarios and mobility models. We identify two main problems, named LLNK and LOOP, that are caused by mobility-induced location errors. Based on analysis via ns-2 simulations, we propose two mobility prediction schemes--- neighbor location prediction (NLP) and destination location prediction (DLP) to mitigate these problems. Simulation results show noticeable improvement under all mobility models used in our study. Our schemes achieve up to 27 % improvement in packet delivery and 37 % reduction in network resource wastage on average without incurring any additional communication or intense computation. 1.
Group and swarm mobility models for ad hoc network scenarios using virtual tracks
- In Proceedings of MILCOM
, 2004
"... The mobility model is one of the most important factors in the performance evaluation of a mobile ad hoc network (MANET). Traditionally, the random waypoint mobility model has been used to model the node mobility, where the movement of one node is modeled as independent from all others. However, in ..."
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Cited by 57 (10 self)
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The mobility model is one of the most important factors in the performance evaluation of a mobile ad hoc network (MANET). Traditionally, the random waypoint mobility model has been used to model the node mobility, where the movement of one node is modeled as independent from all others. However, in reality, especially in large scale military scenarios, mobility coherence among nodes is quite common. One typical mobility behavior is group mobility. Thus, to investigate military MANET scenarios, an underlying realistic mobility model is highly desired. In this paper, we propose a “virtual track ” based group mobility model (VT model) which closely approximates the mobility patterns in military MANET scenarios. It models various types of node mobility such as group moving nodes, individually moving nodes as well as static nodes. Moreover, the VT model not only models the group mobility, it also models the dynamics of group mobility such as group merge and split. Simulation experiments show that the choice of mobility model has significant impact on network performance. I.
Modeling Path Duration Distributions in MANETs and their Impact on Reactive Routing Protocols
- IEEE Journal on Selected Areas in Communications
, 2004
"... We develop a detailed approach to study how mobility impacts the performance of reactive MANET routing protocols. In particular we examine how the statistics of path durations including PDFs vary with the parameters such as the mobility model, relative speed, number of hops, and radio range. We find ..."
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Cited by 53 (6 self)
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We develop a detailed approach to study how mobility impacts the performance of reactive MANET routing protocols. In particular we examine how the statistics of path durations including PDFs vary with the parameters such as the mobility model, relative speed, number of hops, and radio range. We find that at low speeds, certain mobility models may induce multi-modal distributions that reflect the characteristics of the spatial map, mobility constraints and the communicating traffic pattern. However, our study suggests that at moderate and high velocities the exponential distribution with appropriate parameterizations is a good approximation of the path duration distribution for a range of mobility models.
AMOEBA: Robust Location Privacy Scheme for VANET
- IEEE Journal on Selected Areas in Communications
, 2007
"... Abstract — Communication messages in vehicular ad hoc networks (VANET) can be used to locate and track vehicles. While tracking can be beneficial for vehicle navigation, it can also lead to threats on location privacy of vehicle user. In this paper, we address the problem of mitigating unauthorized ..."
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Cited by 41 (3 self)
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Abstract — Communication messages in vehicular ad hoc networks (VANET) can be used to locate and track vehicles. While tracking can be beneficial for vehicle navigation, it can also lead to threats on location privacy of vehicle user. In this paper, we address the problem of mitigating unauthorized tracking of vehicles based on their broadcast communications, to enhance the user location privacy in VANET. Compared to other mobile networks, VANET exhibits unique characteristics in terms of vehicular mobility constraints, application requirements such as a safety message broadcast period, and vehicular network connectivity. Based on the observed characteristics, we propose a scheme called AMOEBA, that provides location privacy by utilizing the group navigation of vehicles. By simulating vehicular mobility in freeways and streets, the performance of the proposed scheme is evaluated under VANET application constraints and two passive adversary models. We make use of vehicular groups for anonymous access to location based service applications in VANET, for user privacy protection. The robustness of the user privacy provided is considered under various attacks. I.
