• 한국산학기술학회논문지
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• 제14권4호
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• pp.1969-1975
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• 2013

ICN(Information-Centric Network)은 인터넷 상에 존재하는 방대한 정보를 효율적으로 이용하기 위하여 기존의 인터넷 통신 패러다임을 정보 기반의 통신 방법으로 전환하기 위한 차세대 인터넷 통신 기술이다. 따라서 ICN은 호스트 주소를 중심으로 통신 절차에 집중하던 기존 인터넷 통신 기술과는 달리 인터넷 상에 존재하는 모든 것을 정보라는 개념으로 정의함으로써 각 정보를 이용하기 위한 통신 목적에 집중한다. 이를 위하여 ICN에서는 각 정보에 이름을 붙여 사용하는 이름 기반 라우팅(NbR, Name-based Routing) 방법을 사용하며 ICN에 참여하는 모든 라우터는 각 라우터 마다 정보를 공유할 수 있도록 물리적인 스토리지를 가지는 특징이 있다. ICN에서의 NbR 방법은 각 라우터에서 보유하고 있는 스토리지에 도달하는 방법에 따라 one-phase routing과 two-phase routing으로 나뉜다. 그러나 현재 제시되고 있는 ICN에서의 NbR 방법은 ICN이 가지고 있는 고유한 특징을 반영하지 못하고 있기 때문에 많은 문제점을 발생시키고 있다. 따라서 본 논문에서는 ICN을 위한 효율적인 NbR 방법을 제시하기 위하여 정보에 대한 캐싱, 접근 시간, 분산, 이동성, 확장성, 배포 측면에서 NbR 이슈들을 점검하고, ICN을 위해 제안된 기존 방법들에 대한 비교 분석을 수행하였다. 또한 분석된 내용을 기반으로 ICN에서의 효율적인 NbR 기법에 대한 연구 방향을 제시하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.552-557
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• 2004

Mobile Ad Hoc Network (MANET) is a network architecture, which has no backbone network and is deployed temporarily and rapidly in emergency or war without fixed mobile infrastructures. All communications between network entities are carried in ad-hoc networks over the wireless medium. Due to the radio communications being extremely vulnerable to propagation impairments, connectivity between network nodes is not guaranteed. Therefore, previously developed routing algorithms in wired networks cannot be used. And many new algorithms have been undergone. This study proposes the secondary leader approach to the cluster based routing protocol(CBRP). In case, the primary leader becomes abnormal status so that the primary leader cannot participate the communications between network entities, the secondary leader immediately replaces the primary header without selecting process of the new primary leader. The performances of proposed algorithm ACBRP(Advanced Cluster. Based Routing Protocol;CBRP using secondary leader) are compared with CBRP and results are presented in order to show the effectiveness of the algorithm.

• International Journal of Internet, Broadcasting and Communication
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• 제12권3호
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• pp.46-55
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• 2020

Ad Hoc network is a special wireless network, mainly because the nodes are no control center, the topology is flexible, and the networking could be established quickly, which results the transmission stability is lower than other types of networks. In order to guarantee the transmission of data packets in the network effectively, an improved Queue Ad Hoc On-demand Distance Vector Routing protocol (Q-AODV) for node detection by using blockchain technology is proposed. In the route search process. Firstly, according to the node's daily communication record the cluster is formed by the source node using the smart contract and gradually extends to the path detection. Then the best optional path nodes are chained in the form of Merkle tree. Finally, the best path is chosen on the blockchain. Simulation experiments show that the stability of Q-AODV protocol is higher than the AODV protocol or the Dynamic Source Routing (DSR) protocol.

• Journal of Communications and Networks
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• 제16권2호
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• pp.146-154
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• 2014

This paper proposes a bandwidth-aware localized-routing algorithm that is capable of sensing the available spectrum bands within a two-hop neighboring for choosing the highly opportunistic routes. A mixed-integer linear programming (MILP) is utilized to formulate the optimization problem. Then, the proposed algorithm is used to determine the maximum bandwidth possible of link pairs via a bandwidth approximation process of relaxed variables. Thereby, the proposed algorithm can allow selected routes corresponding to maximum bandwidth possible between cognitive radio (CR) users through link pairs in cognitive radio networks. By comparing the solution values to previous works, simulation results demonstrate that the proposed algorithm can offer a closed-optimal solution for routing performance in cognitive radio networks. The contribution of this paper is achieved through approximately 50% throughput utilized in the network.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.448-450
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• 2005

A ubiquitous network allows all users to access and exchange information of any kind freely at any time, from anywhere, and from any appliance through the use of broadband and mobile access. Bluetooth commincation can provide the missing wireless extension to the heterogeneous network, allowing a more ubiquitous access. In this point of view, the BT specifications define ways for which each BT device can set up multiple connections with neighboring devices to communicate in a multi-hop fashion. this paper provides insights on the Bluetooth technology and on some limitations of the scatternet formations. so that, we describe a new multi-hop routing protocol for the establishment of scatternets. this protocol defines rules for forming a multi-hop topology in two phases. the first phase, topology discovery, concerns the discovery of the node's depth from a root node initiating inquiry process. the second phase forms scatternet topology based on the result of topology discovery.

• 한국경영과학회지
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• 제14권2호
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• pp.53-66
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• 1989

The Public Vehicle Routing Problem (PVRP) is to find the minimum total cost routes of M or less Public-Vehicles to traverse the required arcs(streets) at least once, and return to their starting depot on a directed network. In this paper, first, a mathematical model is formulated as minimal cost flow model with illegal subtour elimination constraints, and with the fixed cost and routing cost as an objective function. Second, an efficient branch and bound algorithm is developed to obtain an exact solution. A subproblem in this method is a minimal cost flow problem relaxing illegal subtour elimination constraints. The branching strategy is a variable dichotomy method according to the entering nonrequired arcs which are candidates to eneter into an illegal subtour. To accelerate the fathoming process, a tighter lower bound of a candidate subproblem is calculated by using a minimum reduced coast of the entering nonrequired arcs. Computational results based on randomly generated networks report that the developed algorithm is efficient.

• Journal of Electrical Engineering and information Science
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• 제2권3호
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• pp.1-6
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• 1997

This paper describes the design of a network interface controller (NIC) chip which is to be used to support a novel adaptive virtual cut-through routing method for parallel compute systems with direct (i.e., point-to-point) interconnection networks. The NIC chip is designed to provide the interface between a processing node constructed from commercially available microprocessors and another custom-designed router chip, which in turn performs the actual routing of packets to their respective destinations. The NIC, designed using a semi-full-custom VLSi design technique outperform traditional wormhole routing with a minimal amount of hardware overhead. The NIC design has been fully simulated and laid out using a 0.8$\mu\textrm{m}$ CMOS process.

• Journal of Communications and Networks
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• 제16권4호
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• pp.363-370
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• 2014

Despite several years of intense research, the security and cryptography in wireless sensor networks still have a number of ongoing problems. This paper describes how identification (ID)-based node authentication can be used to solve the key agreement problem in a three-layer interaction. The scheme uses a novel security mechanism that considers the characteristics, architecture, and vulnerability of the sensors, and provides an ID-based node authentication that does not require expensive certificates. The scheme describes the routing process using a simple ID suitable for low power and ID exposure, and proposes an ID-based node authentication. This method achieves low-cost communications with an efficient protocol. Results from this study demonstrates that it improves routing performance under different node densities, and reduces the computational cost of key encryption and decryption.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2005년도 추계학술대회 및 정기총회
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• pp.13-18
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• 2005

Routers determine routing path considering network topology and link state information for providing QoS (quality of service) guarantee. Therefore, it is important that routers know link state information to calculate routing path. However, if routers generate link state update messages inordinately, their router performance are reduced due to the process of link state update messages. On the other side, in case that link state information is not updated appropriately, route setup requests can be rejected even though there exist routes. In this paper, we propose an algorithm to improve router performance and evaluate the proposed algorithm performance compare with conventional algorithm by simulations.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.1112-1114
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• 2017

액체 로켓 엔진은 채택되는 사이클, 하드웨어 구성, 기능 구현상의 짐벌 타입 등에 의해 구성품 배치와 레이아웃의 라우팅이 결정된다. 본 논문에서는 액체로켓엔진에 장착되는 주요 구성품을 기준으로 구동을 담당하는 헬륨(He) 공급 공압라인, 각종 퍼지 공압라인, 주 점화라인 등의 주요 유공압 라인의 개념 라우팅을 수행하였다.