• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8B
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• pp.1122-1128
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• 2010

In this paper, we proposed and designed a novel SNA protocol which operates in the way of a server and a client in the power control system. The proposed SNA protocol includes the information about the mode switching, the saving position of context information, the user trigger, and so forth, which are needed in the power management devices. We consider the application of the SNA protocol to the home network, where message flows between the SNA server and the SNA client. To verify the operation of the SNA protocol, the state transition diagrams of the server in the home gateway and the client in the network device are shown. Hence, we can conclude the SNA can operate without malfuction.

• Journal of Communications and Networks
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• v.12 no.5
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• pp.499-509
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• 2010

A plethora of transmission control protocol (TCP) congestion control algorithms have been devoted to achieving the ultimate goal of high link utilization and fair bandwidth sharing in high bandwidth-delay product (HBDP) networks. We present a new insight into the TCP congestion control problem; in particular an end-to-end delay-based approach for an HBDP network. Our main focus is to design an end-to-end mechanism that can achieve the goal without the assistance of any network feedback. Without a router's aid in notifying the network load factor of a bottleneck link, we utilize goodput and throughput values in order to estimate the load factor. The obtained load factor affects the congestion window adjustment. The new protocol, which is called TCP-goodput and throughput (GT), adopts the carefully designed inversely-proportional increase multiplicative decrease window control policy. Our protocol is stable and efficient regardless of the link capacity, the number of flows, and the round-trip delay. Simulation results show that TCP-GT achieves high utilization, good fairness, small standing queue size, and no packet loss in an HBDP environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.3
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• pp.389-399
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• 1998

The DMR-II shared-medium access control protocol was developed for the ATM access network users to supper the isochronous traffic and the non-isochronous traffic simultaneously under the bandwidth-skating environment. In this paper we analyze the performance of the DMR-II protocol by using both the analytical analysis and the simulation method. Under the ATM access network environment, the performance analysis result shows that the DMR-II protocol maintains the delay variation of the isochronous traffic beyond the threshold value, and satisfies the delay time criteria of the non-isochronous traffic by supporting the priority service. Moreover the result shows high network utilization over 130% due to the destination release mechanism of the DMR-II protocol.

• International Journal of Internet, Broadcasting and Communication
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• v.8 no.1
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• pp.53-63
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• 2016

This paper applies WiMedia UWB network into a wireless ship area network (WSAN) so as to support high-quality multimedia services on board and reliable instrument control information as well, since the need for mixed high-quality video traffic and shipboard control data traffic is essential for a high-cost valued digital ship. Thus, in this paper, prioritized contention access (PCA) and distributed reservation protocol (DRP) based on WiMedia UWB (ECMA-368) MAC protocols are combined and proposed to such mixed traffic environment, by varying the portions of superframe according to traffic type. It is shown that the proposed WiMedia UWB MAC protocol can provide reliable mixed video and shipboard control data traffic as well.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.1B
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• pp.39-46
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• 2005

As the multimedia application traffic takes more portion in the internet traffic, it is necessary to control the network congestion through the congestion control protocol. In addition, the QoS-enabled networks such as DiffServ become an indispensable technology when running the multimedia applications. However, the previously proposed end-to-end congestion control algorithms take the round trip time to react the network congestion. Thus, as the RTT becomes larger, the reaction against the congestion gets delayed further, while the network congestion gets worse. In addition the performance of end-to-end congestion control algorithm is degraded if the QoS-enabled network runs the congestion control mechanism in the network level without any coordination between them. In this paper, we propose the early rate adaptation protocol for the DiffServ network which effectively linke the congestion control algorithm at the host and the congestion mechanism in the network together. By taking advantage of early congestion notification from the network it is possible to react the network congestion more quickly and effectively.

• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.37-42
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• 2009

This paper presents an idea of implementation of many semiconductor equipments. The idea is a new design methodology of the Networked Control Systems (NCSs) using CAN (Controller Area Network) will be discussed. The Distributed Control Systems (DCSs) is very useful to control multiple systems that have a distance to communicate. The CAN protocol is very strong to noise, also provides the user with many powerful functionality. Only one communication line (BUS) is used, so that a control and a maintenance of those systems are very easy. This paper is concerned with the speed control of multiple DC motors using CAN Protocol. Experimental systems are made to validate effectiveness of the systems. The results of the experiment show that the NCSs using CAN has excellency in real time control.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3159-3161
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• 1999

This paper aims at developing remote control system to control and monitor distributed various devices through internet or information communication network. SNMP (Simple Network Management Protocol) and UPS (Uninterruptible Power Supply) are adopted for network management protocol and applied device, respectively. For controlling and monitoring distributed devices in real-time, Java-environment software is constructed. Also, general-use interface controller between network device and applied device is proposed. Finally, serial communication such as RS-232 and RS-485 is used between controller and applied device.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.5
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• pp.216-219
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• 2006

This paper presents an XML based standard specification of remote control protocol for home appliances. In the framework level, the XML protocol provides a useful bridge between services and platforms. The proposed protocol has been implemented into a personal video recorder for remote recording service. The results imply the potential of global standards for remote control by its minimum overhead in network and processor. The proposed XML is designated RCXML in this paper.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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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.

• ETRI Journal
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• v.10 no.2
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• pp.3-12
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• 1988

Several ISDN (Integrated Services Digital Network) protocols have implemented at ETRI (Electronics and Telecommunications Research Institute) in an experimental network so that functional characteristics of the protocols under test could be certified against their protocol specifications with the help of the ETRI protocol test facilities. This paper describes ETRI protocol test architecture and its application to testing the NSP (Network Service Part) protocols : MTP (Message Transfer Part) level 3 and SCCP (Signalling Connection Control Part) of the CCITT CCS (Common Channel Signalling ) system No. 7 The test architecture presented here allows tests for two different protocol classes : peer-to-peer and multipeer protocolos. Some extensions are made to the conventional test architectures, namely the test coordination, test result transfer and network state observation method.