• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.4
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• pp.183-189
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• 2018

With the recent advancement of vehicle wireless communication technology, many vehicular clouds have been proposed. The existing research focused on cloud services through data collection based on vehicular networks of mobile V2V (Vehicle-to-Vehicle) and V2I (Vehicle-to-Infrastructure). In this paper, we present a vehicular datacenter model that utilizes the vehicle in the parking space as a resource for the datacenter. Also, we derive resource allocation strategy based on the expected execution time considering the leave rate of each vehicle in our vehicular datacenter model. Simulation results show that our proposed resource allocation strategies outperform the existing strategy in terms of mean execution time.

• Journal of Korean Society of Transportation
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• v.26 no.6
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• pp.93-101
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• 2008

With a spread of mobile devices, the growing trend of integrating wireless communications technologies into transportation systems is advanced. In particular, vehicular ad hoc networks (VANETs) enable vehicles to share traffic information that they have through intervehicle communications. This research focused on the design of an integrated transportation and communication simulation framework to build an environment that is more realistic than previous studies developed for studying VANETs. Developing a VANET-based information model, this research designed an integrated transportation and communication simulation framework in which these independent simulation tools not supporting High Level Architecture (HLA) were tightly coupled and finely synchronized. As a case study, a VANET-based traffic information system was demonstrated based on a real road network and real traffic data. The experiment results showed that the simulation framework was well integrated. The simulation framework designed in this study is expected to contribute to developing the environment to experiment a wide range of VANET applications.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.235-236
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• 2006

IEEE 802.16 networks support mobile stations (MSs) to access broadband wireless networks while moving at a vehicular speed. However, IEEE 802.16 networks do not provide link layer native multicast capability because of point-to-multipoint connection characteristic. Due to this feature, it is not easy to adopt protocols or applications which need native link layer multicast capability. In order to solve the multicast support problem, we use the built-in LAN emulation feature of IEEE 802.16 which is based on Convergence Sublayer (CS). Our proposed operational procedures support not only the delivery of link local scope multicast packets, but also the delivery of non-link local scope multicast packets such as site local or global scope multicast packets. We also present the method of forming multicast Connection Identifier (CID) which is used to transport IP packets over IEEE 802.16 networks.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.05a
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• pp.610-613
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• 2013

Vehicular Ad Hoc NETwork (VANET), a subclass of Mobile Ah Hoc NETwork (MANET) has been a tech-buzz for the last couple of decades. VANET, yet not deployed, promises the ease, comfort, and safety to both drivers and passengers once deployed. The by far most important factor in successful VANET application is the data dissemination scheme. Such data includes scheduled beacons that contain whereabouts information of vehicles. In this paper, we aim at regularly broadcasted beacons and devise an algorithm to disseminate the beacon information up to a maximum distance and alleviate the broadcast storm problem at the same time. According to the proposed scheme, a vehicle before re-broadcasting a beacon, takes into account the current vehicular density in its neighborhood. The re-broadcasters are chosen away from the source of the beacon and among the candidate re-broadcasters, if the density in the neighborhood is high, then the candidate rebroadcaster re-broadcasts the beacon with high probability and with low probability, otherwise. We also performed thorough simulations of our algorithms and the results are sound according to the expectations.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.181-188
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• 2011

With the rapid proliferation of wireless networks and mobile computing applications, the landscape of the network security has greatly changed recently. Especially, Vehicular Ad Hoc Networks maintaining network topology with vehicle nodes of high mobility are self-organizing Peer-to-Peer networks that typically have short-lasting and unstable communication links. VANETs are formed with neither fixed infrastructure, centralized administration, nor dedicated routing equipment, and vehicle nodes are moving, joining and leaving the network with very high speed over time. So, VANET-security is very vulnerable for the intrusion of malicious and misbehaving nodes in the network, since VANETs are mostly open networks, allowing everyone connection without centralized control. In this paper, we propose a weighted intrusion detection method using rough set that can identify malicious behavior of vehicle node's activity and detect intrusions efficiently in VANETs. The performance of the proposed scheme is evaluated by a simulation study in terms of intrusion detection rate and false alarm rate for the threshold of deviation number ${\epsilon}$.

• The KIPS Transactions:PartC
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• v.18C no.6
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• pp.405-412
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• 2011

Our proposed mobility management scheme is based on Multicasting and HIP(Host Identity Protocol) in PMIPv6(Proxy Mobile IPv6) Networks, and allows users to handoff within and across different administrative domains. The main advantage of our scheme is to enable the inter-domain handoff of both types of nodes with a reduced signalling overhead and packet losses. Specifically, the scheme enables the interworking between host-based and network-based mobility support, by means of the interaction between PMIPv6 with Multicasting and HIP. Performance evaluations demonstrate that our scheme improves the handoff latency and packet losses compared to other global mobility management protocols.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.481-484
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• 2012

차로에서 차량의 많은 증가는 안전과 무선통신의 가용성에 대한 필요성을 높여 왔다. Vehicular ad hoc networks(VANETs)은 다양한 차량 어플리케이션을 위한 용도와 상용분야로의 개발을 점차적으로 해오고 있다. 차량 간의 효과적인 통신범위를 제공하기 위해서 최적화된 라우팅 프로토콜이 필요하다. 지금까지 목적지까지 최적의 경로를 찾는 mobile ad hoc networks(MANETs)를 위한 많은 기존의 프로토콜들이 존재한다. 본 논문에서는 두 개의 라우팅 프로토콜들을 비교함으로써 VANET 환경을 위한 프로토콜 개선방향을 제시하였다. Multicast Ad-hoc On-Demand Distance Vector(MAODV)[1][2] 라우팅 프로토콜의 솔루션은 목적지 대상으로 최적의 경로를 탐색함으로써 더욱 향상된 결과를 보여준다. NS-2[3]는 라우팅 프로토콜 실험을 수행하고 결과를 도출하는데 사용되어 왔다. 실험을 통하여 최적의 라우팅 프로토콜에 대한 연구방향 및 개선될 사항을 찾고자 한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.2
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• pp.542-558
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• 2016

Vehicular Ad Hoc Networks (VANETs) are self-configuring networks where the nodes are vehicles equipped with wireless communication technologies. In such networks, limitation of signal coverage and fast topology changes impose difficulties to the proper functioning of the routing protocols. Traditional Mobile Ad Hoc Networks (MANET) routing protocols lose their performance, when communicating between vehicles, compromising information exchange. Obviously, most applications critically rely on routing protocols. Thus, in this work, we propose a methodology for investigating the performance of well-established protocols for MANETs in the VANET arena and, at the same time, we introduce a routing protocol, called Genetic Network Protocol (G-NET). It is based in part on Dynamic Source Routing Protocol (DSR) and on the use of Genetic Algorithms (GAs) for maintenance and route optimization. As G-NET update routes periodically, this work investigates its performance compared to DSR and Ad Hoc on demand Distance Vector (AODV). For more realistic simulation of vehicle movement in urban environments, an analysis was performed by using the VanetMobiSim mobility generator and the Network Simulator (NS-3). Experiments were conducted with different number of vehicles and the results show that, despite the increased routing overhead with respect to DSR, G-NET is better than AODV and provides comparable data delivery rate to the other protocols in the analyzed scenarios.

• International Journal of Computer Science & Network Security
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• v.23 no.2
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• pp.101-110
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• 2023

Vehicular Ad Hoc Network (VANET) is considered to be a subclass of Mobile Ad Hoc Networks (MANET). It has some challenges and issues of privacy which require to be solved before practical implementation of the system i.e., location preservation privacy. Many schemes have been proposed. The most prominent is pseudonym change based location preservation scheme. Safety message can be compromised when it sends via a wireless medium, consequently, an adversary can eavesdrop the communication to analyze and track targeted vehicle. The issue can be counter by use of pseudo identity instead of real and their change while communication proves to be a sufficient solution for such problems. In this context, a large amount of literature on pseudonym change strategies has been proposed to solve such problems in VANET. In this paper, we have given details on strategies proposed last two decades on pseudonym change based location preservation along with issues that they focus to resolve and try to give full understanding to readers.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1269-1277
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• 2008

Ships at sea cannot exchange data among them easily so far. Basically voice-oriented communication systems are the main methods, some of them utilize the HF radio systems at lower bit rates, and for higher bit rates, the Inmarsat or VSAT are adopted. None of them are used widely because of lower qualities and higher costs. There exist many technical and economical limits to have the Internet service just like on land such as the WWW service. In order to achieve the improved transmission rates of the maritime communication networks at farther sea, MANET(Mobile Ad Hoc Network) is one of the most practical models. In this paper, a new routing protocol named EZR (Expansive Search Zone Routing Protocol) is proposed, which is based on SANET (Ship Ad Hoc Network) model that has some different features from MANET and VANET (Vehicular Ad Hoc Network). The search zone for the shortest path is firstly found by EZR. If no path is searched in the zone, the zone is expanded according to the rule of EZR. The zone-expanding and path-searching procedures are repeated until the path is found out. The performance of EZR is evaluated and compared with LAR protocol which is one of the most typical routing protocols based on geographical information. The simulated results show that EZR is much better than LAR at sea environments in terms of routing success rate, route optimality, and a single index of performance combined the previous two metrics.