• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.2A
• /
• pp.203-212
• /
• 2007

An advanced vehicle safety system can be constructed by exchanging danger-related information ,such as urgency stop, traffic accident, obstacle, and car trouble, among the vehicles. However, because network topology changes rapidly and frequently due to the mobility of vehicles, it is impossible to configure the network for information forwarding in this environment. In the most of vehicle safety communication applications, an emergency message is propagated in a form of broadcasting. The simple broadcasting causes a lot of problems in terms of efficiency due to multi-hop area and radio collision problem. This paper proposes a method of selective message forwarding with stem and branch structure for propagating the emergency messages. However, the proposed method raise the efficiency of message transmission with the selective forwarding based on the priority assignment as its location. We analyze and evaluate the performance by comparing the proposed scheme with other schemes that are presented in the paper.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.6 no.2
• /
• pp.70-80
• /
• 2007

Inter-vehicular communication suffers from a variety of the problem on the road, resulting in large delay in propagating emergency warning. An energy depletion as well as a transmission delay may induced by traffic accident. A transmission delay are caused by direct contention from nodes that can hear each other or indirect contention from nodes that can not hear each other, but simultaneously transmit to the same destination. A variety of works have been researched to solve the transmission delay and energy consumption problem in intelligent cars transportation systems. We consider a vehicle-to-vehicle communication protocol for disseminating an emergency information that include end-to-end and energy efficient transmission. In this paper, we propose A vehicle-to-vehicle communication protocol scheme for dissemination emergency information in intelligent cars communication based on IEEE 802.15.3 wireless personal area networks. Results from a simulation study reveal that our scheme can achieves low latency in delivering emergency warnings, and efficiency in consuming energy in stressful road scenarios.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39B no.2
• /
• pp.133-141
• /
• 2014

Recently, various services are provided by using WAVE protocol for communication among neighboring vehicles. And in order to operate stable system, the gateway for interconnecting in and out vehicle networks is required. In this paper, we propose gateway interconnecting WAVE and CAN protocol. The proposed gateway based on OSEK OS consists of a communication layer, a message translator layer and a message management layer. In the communication layer, WAVE communication part and CAN communication part are designed to communicate with WAVE and CAN. And in the message management layer, message management layer functions to store the received messages and check errors with the message. Based on these functions, experiment was conducted to analyze performance of the gateway with two scenarios such as transmitting periodically BSM as a message structure for safety services in vehicle-to-vehicle communications and responding to road side equipments requiring in-vehicle information. As a result of test, we verify our gateway performance by analyzing measured time in test scenarios.

• Journal of the Korea Society for Simulation
• /
• v.20 no.1
• /
• pp.19-28
• /
• 2011

The safety applications based on the IEEE 802.11p, periodically transmit the safety-related information to all surrounding vehicles with high reliability and a strict timeline. However, due to the high vehicle mobility, dynamic network topology and limited network resource, the fixed beacon scheduling scheme excess delay and packet loss due to the channel contention and network congestion. With this motivation, we propose a novel beacon scheduling algorithm referred to as spatial-aware(SA) beacon scheduling based on the spatial context information, dynamically rescheduling the beaconing rate like a TDMA channel access scheme. The proposed SA beacon scheduling algorithm was evaluated using different highway traffic scenarios with both a realistic channel model and 802.11p model in our simulation. The simulation results showed that the performance of our proposed algorithm was better than the fixed scheduling in terms of throughput, channel access delay, and channel load. Also, our proposed algorithm is satisfy the requirements of vehicular safety application.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.39B no.3
• /
• pp.169-179
• /
• 2014

For vehicle safety-related services using wireless communications, reliable collection of various driving informations transmitted periodically by neighbor vehicles is the most important. Every host vehicle analyses them to estimate a potential dangerous situation in a very short time and warns drivers to prevent an accident. However tremendous amount of periodic messages can cause the wireless communication in chaos and the services not in safe. In this paper, we propose a time-division broadcasting protocol to mitigate the communication congestion. It utilizes the received information of vehicle velocity and location, i.e. vehicle traffic density on a road to adjust the number of time slots in a given broadcasting period, and transmission power. The simulation results show that message reception ratio is changed to approximately 40% and channel access time also decreased from 10ms to 0.23ms.

• The KIPS Transactions:PartC
• /
• v.18C no.4
• /
• pp.207-212
• /
• 2011

Vehicular Ad Hoc Network(VANET) is a communication technology between vehicles and vehicles(V2V) or vehicles and infrastructures(V2I) for offering a number of practical applications. Considering the importance of communicated information through VANET, data authentication, confidentiality and integrity are fundamental security elements. Recently, to enhance a security of VANET in various circumstances, message authentication is widely researched by many laboratories. Among of them, Zhang. et. al. is an efficient method to authenticate the message with condition of anonymity in dense space. In the scheme, to obtain the vehicular ID with condition of anonymity, the k-anonymity is used. However it has a disadvantage, which conducts hash operations in case of determining the vehicular ID. In the paper, we present a location based algorithm using received signal strength for the location based authentication and encryption technique as well, and to enhance the accuracy of algorithm we apply a location determination technique over the 3-dimensional space.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.5
• /
• pp.1057-1068
• /
• 2012

According to advance on vehicle technology, many kinds of ECU(Electronic Control Unit) are equipped inside the vehicle. In-vehicle communication among ECUs is performed through CAN(Controller Area Networks). CAN have high reliability. However, it has many vulnerabilities because there is not any security mechanism for CAN. Recently, many papers proposed attacks of in-vehicle communication by using these vulnerabilities. In this paper, we propose an wireless attack model using a mobile radio communication network. We propose a secure authentication mechanism for in-vehicle network communication that assure confidentiality and integrity of data packets and also protect in-vehicle communication from the replay attack.

• 한국IT서비스학회:학술대회논문집
• /
• 2007.11a
• /
• pp.604-608
• /
• 2007

현재 정보통신 기술의 발달에 상응하여 지능형 교통 시스템(ITS)은 네트워크 기반으로 실시간 교통 정보를 제공하기 위해 CCTV, GPS, VDS, 루프 검지기, 영상 검지기 등과 같은 다양한 방법으로 교통 정보 수집이 이루어지고 있다. 또한 정확한 정보 제공을 위해 정보의 수집 및 가공에 대한 많은 연구들이 진행되고 있다. 본 논문에서는 텔레매틱스 기반의 효율적인 교통정보 수집을 위해 RFID 태그 정보를 이용하여 교통정보를 수집하여 보다 정확한 실시간 차량 정보를 제공하는 RFID 기반의 차량점보수집 시스템 모델을 제시하고자 한다.

• Information and Communications Magazine
• /
• v.20 no.12
• /
• pp.14-31
• /
• 2003

텔레매틱스(Telematics)는 자동차와 컴퓨터.이동통신 등 다수의 이종기술의 결합을 의미한다. 텔레매틱스는 또한 유, 무선통신망 등을 통해서 운전자가 정보를 교환하여 운전자 및 차량의 안전 및 편의성을 향상시킬 수 있는 장치 및 서비스를 통칭한다. 휴대용 개인 단말기와 달리 차량에 장착되는 텔레매틱스 단말기는 차량 정보 네트워크에 연결되어 주행 안전이 가장 우선 되어야 하고 부가적인 운전자 정보 서비스가 이루어 져야 한다. 이제까지 제안 또는 적용 되고 있는 기술을 중심으로 텔레매틱스 기술 동향을 요약하였다. 주행 중에 제공되는 서비스로서 텔레매틱스는 안전 관련 제도적 보완이 필요하고 특히 국가 차원의 공공 인프라 지원 정책이 뒷받침되어야만 하는 국가 정책 차원의 지원이 반드시 이루어 져야 한다.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.24 no.5
• /
• pp.73-82
• /
• 2013

최근 차량 네트워크(VANET)는 차량 및 도로 안전에 관한 정보와 다양한 인포테인먼트 서비스 증가로, 기존 차량 통신에 고정적으로 할당된 주파수로는 요구되어지는 주파수 수요량을 충족하지 못할 것으로 예측된다. 이에 따라, 인지 무선(CR) 기술을 VANET 환경의 특징에 적합하게 적용함으로써, 동적인 주파수 사용으로 주파수의 활용도를 향상시키기 위한 연구가 큰 관심을 받고 있다. 본 고에서는 인지 무선을 이용한 차간 통신 이슈 및 연구 동향을 소개한다.