• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.11
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• pp.1077-1082
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• 2016

IDS can be used as a countermeasure for malicious attacks which cause degrade of network transmission performance by disturbing of MANET routing function. In this paper, effects of IDS for transmission performance on MANET under grayhole attacks which has intrusion objects for a part of transmissions packets, some suggestion for effective IDS will be considered. Computer simulation based on NS-2 is used for performance analysis, performance is measured with VoIP(: Voice over Internet Protocol) as an application service. MOS(: Mean Opinion Score), CCR(: Call Connection Rate) and end-to-end delay is used for performance parameter as standard transmission quality factor for voice transmission.

• Journal of Advanced Navigation Technology
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• v.19 no.1
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• pp.53-59
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• 2015

We consider the problems that consist of designing time, establishment cost, delay time and reliability in designing a mesh network when given link costs and traffic requirements between nodes. Designing time, establishment cost and delay time are less, reliability is higher in designing a mesh network. One of the problems designing time is solved by mesh network topology optimization and routing (MENTOR) algorithm that Aaron Kershenbaum propose, but the others remain. In this paper we propose a new mesh network design algorithm with small computational complexity that the others are solved. The result of the proposed algorithm is better than MENTOR's in total establishment cost, delay time and reliability.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.145-148
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• 2003

MPLS is one of the most important technics for the growth of the next generation network. MPLS is a kind of third layers switching technics which is combined with second layers switching speed and third layers routing ability. And a simple label switching paradigm which uses short and fired lengths of lables is available in MPLS, too. Like this way, MPLS not only can keep its competitive price but also keep its merits such as second layers speed, third layers expansion, and compatibility with existing protocols. That means the traffic engineering, VPN, QoS ran be supported easily in MPLS. In this thesis, therefore, we will implement a small inter-networking based on MPLS and analyze its performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3A
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• pp.347-357
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• 2004

Network systems have been developed to meet the high performance of forwarding packets and flexibility for providing various services, so network processor emerged. In order to improve the performance of network processors, fast external interface and special functional units have been used. Recently as an architectural method of improving performance, the SMT(Simultaneous Multi Threading) architecture is proposed, but this architecture is difficult to implement due to its complexity. Therefore research for architectural optimization is needed to develop the SMT network processors. In this paper we analyze each functional units on performing network algorithms and propose an optimized SMT network Processor architecture.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9B
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• pp.883-891
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• 2009

This paper proposes Ethernet linear protection switching technology in order to provide the SONET/SDH-like resiliency over Metro Ethernet Networks. The proposed design is made of an architecture with a control processor board and several data processing boards, where the control processor board is independent of data processing board, providing a flexible solution for carrier Ethernet system. However, it leads an increasing message delay between inter-processors. In this paper, we implement and confirm a restoration of failed transport connections withing 50 millisecond in spite of increasing message delay between the control processing board and data processing board providing carrier-class network survivability.

• Journal of KIISE:Information Networking
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• v.28 no.1
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• pp.173-181
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• 2001

최근 인터넷 사용자의 증가와 서비스의 다양화 그리고 이에 따른 고속 인터넷 엑세스 기술의 도입으로 인터넷 트래픽의 급격한 증가를 초래하고 있다. 이러한 이유로 인터넷 패킷 전달에 2계층 스위칭 기술과 3계층 라우팅 기술을 접목한 IP/ATM Hybrid system이 등장하게 되었다. 이러한 시스템에서의 중요한 자원은 2계층 스위칭 기술을 사용하기 위한 유한한 VCI/VPI 공간이다. 이 VCI/VPI 공간을 효과적으로 관리하기 위한 방안으로 많은 방안들이 제시되고 있다. 특히 흐름 기반의 IP/ATM Hybrid system에서의 흐름 분류기를 사용함으로서 VCI/CPI 공간을 관리하고 있다. 본 논문에서 주장하는 적응형X/Y 분류기가 유한한 VCI/VPI 공간을 효율적으로 관리하기 위한 방안임을 제시하고 이에 대하여 실험을 통하여 성능 평가를 실시하였다 특히 동일한 VCI/VPI 공간에서 X/Y분류기와의 비교실험에서 적응형 X/Y 분류기의 성능이 높은 스위칭 율로 나타나고 있다. 즉 적응형 X/Y 분류기가 X/Y분류기에 비하여 효율적으로 VCI/VPI를 관리함을 보이고 있다

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.3
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• pp.47-54
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• 2004

By using wireless terminal, the number of users who wish to use the multimedia service like the Internet as well as Short Message Services and voice service has increased dramatically over the last years. We propose the method that improves Mobile IPv4 (MIPv4) Regional Registration in wireless mobile networks to decrease traffic's transmission delay and message generation compared with an existing method We design the scheme in MIPv4 environments that a packet do not pass through the home agent transmitted from correspondent node to mobile node, if a mobile node moves to other mobility agent. Simulation results show that the proposed method significantly reduces the expenses for registration and delivering packet.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.8
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• pp.2090-2095
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• 1998

In this paper, we measured voice packet loss over the Korean Internet and analyzed percentage articulation by variation of the packet loss. To do this, we reviewed real-time transmission service based on RTP/UDP/IP and test method of the transmission quality. and implemented the real-time speech transmission system using GSM and UDP/IP. Monosyllable list has been chosen for the percentage articulation test, each voice packet has been coded and compressed by GSM and it has sequence number to measured packet loss and to recover out-of-order packets. In transmission results using seven router over the Korean Internet, we have show that loss rates reached 1.6% (unload), 22.5%(load) and loss rates after packet recovery by resequencing and FEC are from 9% to 35%. Finally, we have shown that percentage articulations by variation of the network traffic are Table 4.

• The KIPS Transactions:PartB
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• v.18B no.3
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• pp.157-164
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• 2011

This paper presents a fast and scalable re-routing algorithm that adapts to dynamically changing networks. The proposed algorithm integrates Dijkstra's shortest path algorithm with the genetic algorithm. Dijkstra's algorithm is used to define the predecessor array that facilitates the initialization process of the genetic algorithm. After that, the genetic algorithm re-searches the optimal path through appropriate genetic operators under dynamic traffic situations. Experimental results demonstrate that the proposed algorithm produces routes with less traveling time and computational overhead than pure genetic algorithm-based approaches as well as the standard Dijkstra's algorithm for large-scale networks.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2764-2771
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• 1999

ATM has recently received much attention because of its high capacity, its bandwidth scalability, and its ability to support multiservice traffic. However, ATM is connection oriented whereas the vast majority of modern data networking protocols are connectionless. The alternative to support current service on ATM will be a router with attached switching hardware that has the ability to cache routing decisions. In this paper, we described the router using a switch and simulated the performance. From the results of the simulation, the routing delay was decreased as the number of flow channels. Cell-delay was shortest at 30,000 cell-time when the keeping time of a flow channel was. The line utilization was rapidly decrease when a flow-setup time is 20 30 cell-time. The results of this simulation could be applied to predict the performance of the router using ATM switch.