• Journal of Information Processing Systems
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• 제2권1호
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• pp.48-51
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• 2006

To achieve security in wireless sensor networks (WSN), it is important to be able to encrypt messages sent among sensor nodes. We propose a new cryptographic key management protocol, which is based on the clustering scheme but does not depend on the probabilistic key. The protocol can increase the efficiency to manage keys since, before distributing the keys by bootstrap, the use of public keys shared among nodes can eliminate the processes to send or to receive keys among the sensors. Also, to find any compromised nodes safely on the network, it solves safety problems by applying the functions of a lightweight attack-detection mechanism.

• 한국정보처리학회논문지
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• 제3권4호
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• pp.709-719
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• 1996

DHCP는 호스트에게 IP(Internet Protocol) 주소나 구성 파라미터 (Configuration Parameter) 등을 동적으로 할당해주는 프로토콜이다. 그러나 이프로토콜은 메시지를 교환하기 위해 브로드캐스팅을 이용하기 때문에 네트워크에 과중한 트래픽의 발생 요인이 된다. 이러한 오버헤드를 줄이기 위해 메시지 교환시에 가능하면 브로드 캐스 팅을 피하고, 간결하고 효율적인 클라이언트-서버의 동작 메처니즘을 설계하였다. 본 연구에서는 DHCP가 유발하는 브로드캐스팅 트래픽 특성을 고찰하여 메시지를 유치캐스트 할 수 있는 방안과 트래픽을 줄일 수 있도록 알고리즘을 개선한 DHCP의 모델을 구현하였다.

• Journal of information and communication convergence engineering
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• 제6권4호
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• pp.466-469
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• 2008

The existing routing protocols in USN environment, PEGASIS is more efficient than LEACH, which is a hierarchical routing protocol, for network configuration based on power consumption. Despite its merit that it can reduce energy consumption per node, however, the PEGASIS protocol also has a weakness that it is less responsive to frequent changes that occur in the configuration of sensor network due to BS nodes that keep changing, which is a typical characteristic of the sensor network. To address this problem, this paper proposes to select sub-cluster heads and have them serve as intermediate nodes. This paper presents and analyses that this method can resolve the aforementioned problem of the PEGASIS algorithm.

• 디지털콘텐츠학회 논문지
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• 제3권2호
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• pp.187-196
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• 2002

DHCP의 기능을 확장하여 mobile IP의 홈 에이전트 및 외부 에이전트의 기능을 수용하도록 함으로써 DHCP 노드가 동적 IP 할당의 전 프로세스를 수행하게 하여 에이전트를 통한 이동 IP 할당보다. 단순한 구조를 유지하게 한다. DHCP는 윈도우즈 NT 계통의 운영체제를 사용하는 단말기에서 기본적으로 제공되고 있다. 여기에 mobile IP의 기능을 별도의 프로세스로 장착하지 않고 DHCP메시지의 옵션 필드들을 이용해 mobile IP의 기능이 DHCP 노드에서 이뤄질 수 있도록 제안하였다.

• Journal of information and communication convergence engineering
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• 제18권1호
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• pp.8-15
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• 2020

Internet-of-Things (IoT) technologies are used everywhere, and communication is one of its core and essential aspect. To solve the networking and communication of small IoT terminals, in this paper, a communication scheme based on low-cost WiFi is proposed, which also has the advantages of good compatibility and low power consumption. At the same time, it has a convenient one-key configuration mode, which reduces the technical requirements for operators. In this study, a communication protocol is designed that mainly aims at up to dozens of domestic IoT terminals, in which the amount of data is not large, data exchange is not high, and network is unstable. According to the alarm data, update data, and equipment or network fault, the protocol can respectively transmit in real time, regularly and repeatedly. This protocol is open and easy to integrate, and after cooperating with tiny encryption algorithm, information can be safely transmitted.

• 한국통신학회논문지
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• 제32권10A호
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• pp.1004-1014
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• 2007

In sensor networks, it is crucial to reliably and energy-efficiently deliver sensed information from each source to a sink node. Specifically, in mobile sink (user) applications, due to the sink mobility, a stationary dissemination path may no longer be effective. The path will have to be continuously reconfigured according to the current location of the sink. Moreover, the dynamic optimal path from each source to the sink is required in order to reduce end-to-end delay and additional energy wastage. In this paper, an Adaptive Reversal Optimal path Tree (AROT) protocol is proposed. Information delivery from each source to a mobile sink can be easily achieved along the AROT without additional control overhead, because the AROT proactively performs adaptive sink mobility management. In addition, the dynamic path is optimal in terms of hop counts and the AROT can maintain a robust tree structure by quickly recovering the partitioned tree with minimum packet transmission. Finally, the simulation results demonstrate that the AROT is a considerably energy-efficient and robust protocol.

• 한국컴퓨터정보학회논문지
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• 제21권1호
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• pp.39-47
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• 2016

In this paper, we propose vehicle SoC fault diagnosis platform using FlexRay protocol in order to detect the faults of semiconductor control chip even after vehicle production. Before FlexRay protocol by sending NFI (Null Frame Indicator) bit among the header segment and a specific identifier in the payload segment of FlexRay frame, this technique can be distinguishable from normal mode and test mode. By using this technique, it is possible to detect the faults such as performance degradation of vehicle network system caused by the aging or several problems of vehicle semiconductor chip. Also high reliability and safety of vehicle can be maintained by using structural test for vehicle SoC fault detection.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권8호
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• pp.492-499
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• 2003

This paper presents the analysis and the implementation of the asynchronous communication portion of the IEEE 802.11 MAC protocol. We have used PRISM2 chipsets from INTERSIL to build baseband, IF, and RF parts and PCI controller from PLX to interface LLC Layer. We have implemented DCF(Distributed Coordination Function) service using CSMA/CA(Carrier Sense Multiple Access with Collision Acoidance) with backoff algorithm and RTS/CTS protocol. Also, we have implemented TSF(Timing Synchronization Function) which can be used for power management frequency hop synchronization, and other management function. This study can be used as a reference for the MAC protocol implementation and MAC controller design in very high speed wireless LAN which complies with the IEEE 802.11 standard.

• Journal of electromagnetic engineering and science
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• 제12권2호
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• pp.135-141
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• 2012

In this paper, we propose a novel cooperative routing protocol (NCRP) for wireless networks. The proposed protocol uses cooperative transmission to improve end-to-end outage probability. The broadcast nature ensures that the destination can receive a packet from the source or from the relays and if it cannot correctly decode the packet, the successful relays will start a retransmission. The NCRP protocol can skip some transmissions from the intermediate relays, thereby reducing the total power consumption. Theoretical results are derived and verified by simulation results.

• 한국산학기술학회논문지
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• 제9권6호
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• pp.1647-1652
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• 2008

USN 환경에서 제안된 라우팅 프로토콜 중에서 PEGASIS 프로토콜은 LEACH 프로토콜과 비교해 볼 때 노드의 에너지 소비량 감소에 효과적이다. 하지만, PEGASIS 프로토콜은 센서 네트워크의 특성인 BS 노드의 빈번한 변경으로 인한 센서 네트워크 망 구성의 변화에 취약성을 가지고 있다. 이에 본 논문에서는 이를 해결하기 위해서 작은 단위의 클러스터 헤드를 선출해 중간노드의 역할을 하게 하고자 한다. 이를 통해 PEGASIS 알고리즘이 가지고 있는 취약점을 보완할 수 있음을 보이고 이에 대한 시뮬레이션 결과를 보인다.