• 전자공학회논문지A
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• 제31A권7호
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• pp.17-28
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• 1994

A combined random/reservation multiple access protocol is proposed which can provide services for packet transmission in mobile satellite systems between mobile statons, or between mobile stations and fixed stations. Random multiple access protocol and reservation multiple access protocol which are currently employed in most satellite communication systems have some strengthes and some weeknesses in according to the kind of user and traffic. In this paper, a combined random/reservation multiple access protocol with better characteristics is proposed. The models of the modified random access protocol and the proposed access protocol is setted and analyzed. The performance of the PDAMA protocol, the random access protocol and the proposed access protocol is compared using simulation. For small packet arrival rate, the performance of the proposed access protocol is close at that of the modified random access protocol, and better than that of the PDAMA protocol. As the packet arrival rate is increased, the modified random access protocol is saturated and unstable at 0.23, and the performance of the proposed access protocol is better than that of the PDAMA protocol.

• ETRI Journal
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• 제11권4호
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• pp.22-36
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• 1989

In this paper, a design and implementation of an efficient protocol verification system named LOVE has been described. The LOVE has been developed specifically for LOTOS. It performs not only protocol syntax validation (PSV) but also protocol functional verification(PFV). The PSV is a test to check if a protocol is free from protocol syntax errors such as deadlocks and livelocks. The PFV confirms whether or not a protocol achieves its functional objectives. For the PSV, the reachability analysis is employed, and the observational equivalence test is used for the PFV. For protocol verification using the LOVE, a schematic protocol verification methodology has been outlined.

• Journal of Information Processing Systems
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• 제6권1호
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• pp.43-52
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• 2010

In the secure communication areas, three-party authenticated key exchange protocol is an important cryptographic technique. In this protocol, two clients will share a human-memorable password with a trusted server, in which two users can generate a secure session key. On the other hand the protocol should resist all types of password guessing attacks. Recently, STPKE' protocol has been proposed by Kim and Choi. An undetectable online password guessing attack on STPKE' protocol is presented in the current study. An alternative protocol to overcome undetectable online password guessing attacks is proposed. The results show that the proposed protocol can resist undetectable online password guessing attacks. Additionally, it achieves the same security level with reduced random numbers and without XOR operations. The computational efficiency is improved by $\approx$ 30% for problems of size $\approx$ 2048 bits. The proposed protocol is achieving better performance efficiency and withstands password guessing attacks. The results show that the proposed protocol is secure, efficient and practical.

• 한국통신학회논문지
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• 제32권7B호
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• pp.403-410
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• 2007

IPv6 유무선 로컬 네트워크에서 이웃하는 호스트와 라우터를 발견하기 위한 목적으로 ND (Neighbor Discovery) 프로토콜이 제안되었다. 그러나 ND 프로토콜은 악의 있는 사용자가 프로토콜 메시지를 위조하여 정상적인 호스트나 라우터로 위장하는 것이 가능하기 때문에 네트워크 공격에 취약한 문제를 가지고 있다. ND 프로토콜을 보호하기 위한 목적으로 SEND (Secure Neighbor Discovery) 프로토콜이 제안되었다. SEND 프로토콜은 주소 소유권 증명, 메시지 보호, 재현 공격 방지, 그리고 라우터 인증 메커니즘을 제공한다. 본 논문에서는 IPv6 네트워크상에서 핵심적으로 운용될 프로토콜중의 하나인 SEND 프로토콜을 설계 및 구현하다. 또한 본 논문에서 구현한 SEND 프로토콜을 IPv6 네트워크상에서 실험함으로써 SEND 프로토콜의 공격 방어 능력과 프로토콜의 성능을 평가하고 분석한다.

• 정보처리학회논문지D
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• 제8D권5호
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• pp.523-532
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• 2001

원자성 완료규약 분산트랜잭션을 규약에 참여하는 사이트에 일관되게 종료할 수 있게 한다. 사이트 나 통신의 고장에도 불구하고 참여자들이 트랜잭션을 정확하게 종료할 수 있다면 이것은 봉쇄문제를 제거한 규약이라 한다. 2PC 규약은 봉쇄 규약으로 유명하고, 반면에 3PC 규약은 봉쇄문제를 해결한 규약으로 알려졌다. 본 논문에서 제안된 봉쇄 해결 규약보다 봉쇄문제를 축소한 NB-2PC 규약을 제안한다. NB-2-PC 규약은 2PC 규약과 3PC규약을 변형한 규약이다. NB-2PC 규약은 선출단계에서 참여자들이 조정자에게 Prepare 메세지를 받으면, 조정자와 여러 참여자들에게 응답 메세지를 보낸다. 참여자들은 결정 메세지를 기다리다 조정자의 고장으로 인해 봉쇄 문제가 발생하면 Prepare 메세지를 보낸 참여자들 중에서 새로운 조정자를 선출한다. 참여자는 종료규약을 수행하여 봉쇄문제를 줄인다. 본 논문에서는 NB-2PC 규약의 기본적인 구조와 종료규약, 새로운 조정자 선출 방법을 제안한다. 또한 실험을 통하여 NB-2PC 규약이 3PC 규약보다 완료규약 수행시간이 우수하다는 것을 보인다.

• 한국철도학회논문집
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• 제7권2호
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• pp.114-119
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• 2004

According to the computerization of railway signalling systems. the communication protocol for interface between these systems are required. Therefore the new communication protocol for railway signaling system is required. Generally, there are two verification method for new designed protocol in the industrial and academic fields. One is the laboratory testing method which is very popular and general technique. In our research the comparison between existing and new designed protocol for signaling is described and the verification test results are also represented. From these laboratory test, we are verified the conformance of new designed protocol. Another method is verified by formal method. The format verification method is widely used at safety-critical system design but this approach is nor popular at verification communication protocol. However it is very important to verify the safety of new designed protocol for railway signaling system because signaling systems are very safety-critical systems. So, the methodology for formal verification of designed protocol is also reviews in this paper.

• 한국통신학회논문지
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• 제22권1호
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• pp.151-161
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• 1997

In this paper we designed a high speed wireless multiple access protocol, which is suitable for future multimedia wireless LAN systems which support high quality video teleconferencing, telephony and graphic databases. In the proposed protocol, Slotted-ALOHA protocol is used for transmitting random data packets and the packet reservation multiple access(PRMA) protocol for transmitting periodic data packets. The use of minislot is introduced for the reservation scheme. In order to measure the performance characteristic of the proposed protocol, a simulator is designed using an object oriented programming language, C++, and an exhaustive simulation study is carried out. From the simulation results, it is observed that the proposed protocol and the existing PRMA protocol have almost the same delay characteristic when network traffic is low. However, the proposed protocol is superior to the PRMA protocol when traffic becomes higher. The proposed protocol and the results can be utilized for the design of the wireless access systems and future broadband wireless LANs.

• 제어로봇시스템학회논문지
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• 제6권7호
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• pp.594-601
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• 2000

EIA-709.1 Control Network Protocol is the basic protocol of LonWorks systems that is emerg-ing as a fieldbus device. In this paper the protocol is implemented by using VHDL with FPGA and C program on an Intel 8051 processor. The protocol from the physical layer to the network layer of EIA-709.1 is im-plemented in a hardware level,. So it decreases the load of the CPU for implementing the protocol. We verify the commercial feasibility of the hardware through the communication test with Neuron Chip. based on EIA-709.1 protocol which is used in industrial fields. The developed protocol based on FPGA becomes one of IP can be applicable to various industrial field because it is implemented by VHDL.

• 스마트미디어저널
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• 제8권3호
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• pp.9-16
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• 2019

애플사는 장비 간 간편한 파일 송수신을 위해 자체적인 프로토콜인 Bonjour 프로토콜을 제공한다. 대표 서비스로는 Airdrop이 있으며, 애플사의 데스크탑, 노트북, 스마트폰 간에 간편한 데이터 송수신 프로토콜로 널리 사용되고 있다. 하지만, 2016년 해킹 보안 컨퍼런스인 Black Hat에서 Bonjour 프로토콜 취약점을 통해 중간자 공격이 가능함을 보였다. 본 논문은 장비 간 안전한 파일 송수신을 위해 Bonjour 프로토콜의 알려진 취약점을 설명하고, Bonjour 프로토콜의 안전성을 높이기 위해 ECDH(Elliptic Curve Diffie-Hellman) 기반 인증 프로토콜을 제안한다. 제안된 프로토콜을 상세한 동작 프로시저와 함께 설명하며, 중간자 공격과 신분위장 공격 가능성을 줄일 수 있음을 증명한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
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• pp.81-84
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• 2000

This paper has been studied a interworking signalling protocol between two hybrid networks by analyzing Satellite B-ISDN architecture, DSS2 Layer 3 Signalling protocol B-ISUP protocol, S-BISUP protocol stack and so on. Also in the paper, messages and primitives have been defined for B-ISDN's Connection Type, Ownership and each protocol in order to connect point-to-multipoint. And then this paper has designed basic call procedures for OBP Satellite B-ISDN NNI inter-working protocol, verified and implemented them.