• 한국컴퓨터정보학회논문지
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• 제6권4호
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• pp.68-73
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• 2001

MPLS(Multi protocol Label Switching)는 Network Traffic 흐름의 속도를 높이고 관리하기 쉽게 하기 위한 표준 기술이다. MPLS는 정해진 Pack 열에 특정 경로를 설정하는 것에 관여하고, 각 Pack 내에는 라벨이 있어 Router 입장에서는 그 Pack을 전달할 노드의 주소를 확인하여 소요시간을 절약한다. MPLS는 IP, ATM및 프레임 릴레이 Network protocol 등과 같이 작동한다. MPLS는 Network OSI 참조모델과 함께 3Layer가 아닌 Switching을 하는 2Layer에서 대부분의 Pack이 전달되게 한다. MPLS는 Traffic을 빠르게 움직이게 하며, QoS를 위한 Network관리를 쉽게 한다. 이런 이유에 MPLS 기술은 더 많고 특정한 Traffic을 전송하기 시작한 Network로 채택될 유망한 기술로 기대되고 있다.

• 디지털산업정보학회논문지
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• 제8권1호
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• pp.47-53
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• 2012

Sensor networks and car networks that have different structure from that of conventional TCP/IP network require extreme network environment due to frequent change of connectivity. Because such extreme network environment has characteristics like unreliable link connectivity, long delay time, asymmetrical data transfer rate, and high error rate, etc., it is difficult to perform normally with the conventional TCP/P-based routing. DTNs (delay and disruption tolerant network) was designed to support data transfer in extreme network environment with long delay time and no guarantee for continuous connectivity between terminals. This study suggests an algorithm that limits the maximum number of copying transferred message to L by improving the spray and wait routing protocol, which is one of the conventional DTNs routing protocols, and using the azimuth and density data of the mobile nods. The suggested algorithm was examined by using ONE, a DTNs simulator. As a result, it could reduce the delay time and overhead of unnecessary packets compared to the conventional spray and wait routing protocol.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제5권5호
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• pp.619-627
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• 1999

서로 다른 네트워크 환경을 갖는 도메인 사이에서 멀티미디어 서비스를 제공하기 위해서는 여러 가지 측면에 대한 기능 대응이 이루어져야 한다. 본 논문에서는 ATM 기반의 DAVIC(Digital Audio Visual Council) 서비스와 인터넷 AV 서비스를 연동하기 위하여, 프로토콜 변환 및 QoS(Quality of Service) 적응을 지원하는 연동 게이트웨이를 구현하였다. 구현된 연동 게이트웨이는 ATM 망에서 DSM-CC (Digital Storage Media Command & Control)를 기반으로 서비스되는 스트림을 RTSP(Real-Time STreaming Protocol)로 제어할 수 있으며, RTP(Real-Time Transport Protocol)를 이용하여 스트림을 전달한다. 또한 네트워크 대역폭 변화를 고려한 스트림 전달을 위해 QoS 모니터링과 MPEG 필터링을 이용한 QoS 적응 기능을 제공한다.

• International journal of advanced smart convergence
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• 제6권3호
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• pp.53-58
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• 2017

A WSN (Wireless Sensor Network) is a network that is composed of wireless sensor nodes. There is no restriction on the place where it can be installed because it is composed wirelessly. Instead, sensor nodes have limited energy. Therefore, to use the network for a long time, energy consumption should be minimized. Several protocols have been proposed to minimize energy consumption, and the typical protocol is the LEACH protocol. The LEACH protocol is a cluster-based protocol that minimizes energy consumption by dividing the sensor field into clusters. Depending on how you organize the clusters of sensor field, network lifetimes may increase or decrease. In this paper, we will improve the network lifetime by improving the cluster head selection method in LEACH Protocol.

• 전기학회논문지P
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• 제52권3호
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• pp.95-99
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• 2003

In this paper, the power system automation based on CAN communication protocol is introduced. Along with digitalization of electrical device, the various on-line services such as remote control, remote monitoring, remote parameter setting, fault data recording and remote diagnostic have been realized and become available. Therefore, it is necessary for those electrical devices to have real-time and reliable communication protocols. Author proposes DNPC(Distributed Network Protocol with CAN) which is proper to the power system SCADA (Supervisory Control And Data Acquisition) and DCS (Distributed Control System). The physical and datalink layer of DNPC protocol consists of the CAN2.0B which has the real-time characteristics and powerful error control scheme. As the transport and application layer, DNP3.0 is adopted because of its flexibility and compatible feature. Using the DNPC protocol, the power system automation is realized.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권1호
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• pp.135-158
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• 2018

High-Speed vehicles can be considered as multiple mobile nodes that move together in a large-scale mobile network. High-speed makes the time allowed for a mobile node to complete a handover procedure shorter and more frequently. Hence, several protocols are used to manage the mobility of mobile nodes such as Network Mobility (NEMO). However, there are still some problems such as high handover latency and packet loss. So efficient handover management is needed to meet Quality of Service (QoS) requirements for real-time applications. This paper utilizes the cross-layer seamless handover technique for network mobility presented in cellular networks. It extends this technique to propose QoS-aware NEMO protocol which considers QoS requirements for real-time applications. A novel analytical framework is developed to compare the performance of the proposed protocol with basic NEMO using cost functions for realistic city mobility model. The numerical results show that QoS-aware NEMO protocol improves the performance in terms of handover latency, packet delivery cost, location update cost, and total cost.

• 제어로봇시스템학회논문지
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• 제13권10호
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• pp.933-939
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• 2007

Safety critical systems such as x-by-wire systems require in-vehicle network systems that can interconnect various sensors, actuators, and controllers. These networks need to have high data rate, deterministic operation, and fault tolerance. Recently, FlexRay protocol that is a time-triggered protocol has been introduced, and many automotive companies have been focusing on this protocol. This paper presents a design method of FlexRay network system and implementation of FlexRay-based motor control system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1129-1132
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• 1999

This paper deals with the design and implementation of an Ethernet-based communication protocol to be used in PC-based I/O interface systems. Recently, the performance of PC systems is being highly improved and Ethernet is used as the stable communication network over the world. We develop a new protocol driver with the capability of accessing Ethernet directly using NDIS(Network Driver Interface Specification), the network interface standard of Windows O.S. in PC, and install it at the application layer of the protocol structure. Its major roles are the supplement of CSMA/CD algorithm, the effective use of the long data frame of Ethernet, and the real-time transmission of data frames. This paper represents the possibility of the real-time control network and systems based on PCs and Ethernet.

• 제어로봇시스템학회논문지
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• 제11권8호
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• pp.709-716
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• 2005

As a way to build more efficient and intelligent container cranes for todays hub ports, communication networks are used to interconnect numerous sensors, actuators, controllers, and operator switches and consoles that are spatially distributed over a crane. Various signals such as sensor values and operator's commands are digitized and broadcast on the network instead of using separate wiring cables. This not only makes the design and manufacturing of a crane more efficient, but also easier implementation of intelligent control algorithms. This paper presents the performance evaluation of CAN(Controller Area Network), TTP(Time Triggered Protocol) and Byteflight that can be used for cranes. Through discrete event simulation, several important quantitative performance factors such as the probability of a transmission failure, average system delay (data latency) and maximum system delay have been evaluated.

• 한국군사과학기술학회지
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• 제11권3호
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• pp.106-114
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• 2008

In this paper we suggest a protocol and an algorithm which connect a secure channel between a server and a client over a TCP layer. To make key exchange time the most quickly, the protocol adopts ECC Diffie Hellman(ECCDH) algorithm. And the protocol does not use Hello message for key exchanges and state changes. We also implement this protocol over an open TCP/IP program and check the secure channel connecting time over the military computer network. The suggested protocol could be practically used on the military computer network without a hardware implementation.