• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권6호
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• pp.1901-1913
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• 2014

The IEEE 802.15.6 is a communication standard for Wireless Body Area Networks (WBANs). This standard includes a prioritized slotted Aloha as a choice for medium access control. This protocol is different from the traditional version as it has integral considerations for certain priorities of users. It attempts to resolve collision by halving the probability of retransmission, lower bounded by to a minimum, in the alternate slots to follow. In this paper, we present an analytical model to compute the non-saturated throughput of this protocol in the presence of finite number of nodes. The model is validated against simulation.

• 중소기업융합학회논문지
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• 제4권3호
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• pp.21-25
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• 2014

Group communications are becoming popular in Internet applications such as video conferences, on-line chatting programs, games, and gambling. Secure and efficient group communication is needed for message integration, confidentiality, and system usability. However, the conventional group key agreement protocols are too much focused on minimizing the computational overhead by concentrating on generating the common group key efficiently for secure communication. As a result, the common group key is generated efficiently but a failure in authentication allows adversaries to obtain valuable information during the group communication. After achieving the secure group communication, the secure group communication should generate the group key efficiently and distribute it to group members securely, so the balance of security and system usage must be considered at the same time. Therefore, this research proposes the software architecture model of a secure and efficient group communication that will be imbedded into networking applications.

• 한국CDE학회논문집
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• 제8권3호
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• pp.141-149
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• 2003

The ship STEP is an international standard for the computer-interpretable representation of ship product information and for the exchange of ship product model data. The ship STEP consists of several APs(Application Protocol), such as AP215(ship arrangement), AP216(ship moulded form), AP218(ship structures), AP226(ship mechanical systems), and AP234(operating logs, records, message). The STEP AP216(ISO 10303) are an application protocol for the exchange of ship arrangement and ship moulded forms. The AP216 specifies the geometric shape and the hydrostatic properties of the ship moulded form. This paper introduces the state-of-the-art of ship STEP AP216 and develops the test case for the validation of data structure of AP216.

• 한국컴퓨터정보학회논문지
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• 제23권2호
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• pp.53-61
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• 2018

In this paper, the author proposes an efficient group key agreement scheme in a mobile environment where group members frequently join and leave. This protocol consists of basic protocols and general ones and is expected to be suitable for communications between a mobile device with limited computing capability and a key distributing center (or base station) with sufficient computing capability. Compared with other schemes, the performance of the proposed protocol is a bit more efficient in the aspects of the overall cost for both communication and computation where the computational efficiency of the scheme is achieved by using exclusive or operations and a one-way hash function. Also, in the aspect of security, it guarantees both forward and backward secrecy based on the computational Diffie-Hellman (CDH) assumption so that secure group communication can be made possible. Furthermore, the author proves its security against a passive adversary in the random oracle model.

• Journal of Communications and Networks
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• 제14권1호
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• pp.40-50
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• 2012

The Berkeley-medium access control (B-MAC) is a lightweight, configurable and asynchronous duty cycle medium access control (MAC) protocol in wireless sensor networks. This article presents an analytic modelling of single-hop B-MAC protocol under a Poisson traffic assumption.Our model considers important B-MAC parameters such as the sleep cycle, the two stage backoff mechanism, and the extended preamble. The service delay of an arriving packet and the energy consumption are calculated by an iterative method. The simulation results verify that the proposed analytic model can accurately estimate the performance of single-hop B-MAC with different operating environments.

• 한국정보처리학회논문지
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• 제6권10호
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• pp.2740-2751
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• 1999

Critical to more widespread use of Internet telephony are the smooth interoperability with the existing telephone network and the improved quality of voice connections. Of these requirements, this interoperability comes through the use of Internet Telephony Gateway's which perform protocol translation between an IP network and the Public Switched Telephone Network. In this paper, we have focused on the necessity and possibility of interoperability, and furthermore derives the necessary requirements for interoperability between IP networks and PSTN. For this purpose, we have analyzed the signaling protocols for gateway system. Then, we have modelled the inter-working part using the Petri-Net model. Through reachability trees of the Petri-Net model, we have confirmed that interoperability is possible, and that characteristics of deadlock, liveness, and boundness are satisfied.

• 전기학회논문지
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• 제58권11호
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• pp.2253-2260
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• 2009

BACnet is an international standard communication protocol especially designed for building automation and control systems. In this paper, a reference model of network management system for BACnet is proposed and its implementation method is introduced. In order to evaluate the feasibility and validity of proposed network management system, it is applied to a real experimental model of BACnet network system. Proposed network management system complies with standard BACnet protocol and its functions are implemented in software without hardware dependencies so that it can be applied not only to newly installed BACnet system but also to already installed BACnet system by software upgrade. The network management system and its implementation method introduced in this paper will help BACnet-based automation system to be managed efficiently and they can be practically applied in real BACnet-based automation systems.

• 정보보호학회논문지
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• 제5권1호
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• pp.65-84
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• 1995

개방형 시스템에서 사용자에게 안전성 및 신뢰성을 보증하기 위하여 정보 보호가 필요하다.본 논문에서는 트랜스포트 계층에서 보호서비스를 제공하기 위하여 ISO와 IEC에서 표준으로 권고하고 있는 트랜스포트 계층 보호 프로토콜과 보호연관 프로토콜을 분석하고, 표준에서는 정의하지 않았으나 구현상 필요한 세부 사항들을 정의한다. 그리고 구현 모델을 제시하고 이에 기초하여 보호시스템을 개발한다. 개발을 위한 환경으로는 USL의 ONP를 사용한다.

• 한국경영과학회지
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• 제22권2호
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• pp.31-44
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• 1997

This paper presents an approximate analytical model to estimate the mean packet walting times at the stations in the IEEE 802, 6 subnetwork of a metropolitan area network. Each station is modeled as a two queue single server system, which serves data packets and requests from downstream stations according to the DQDB protocol. The model estimates the mean waiting time of the requests and in turn, using the discrete time work conservation law, estimates the mean waiting time for packets. Simulation experiments shows that the model accurately works even under very high traffic loads.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 춘계학술발표논문집 (하)
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• pp.1137-1140
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• 2001

This thesis defines an end-to-end billing process model. The processes in the model can be mapped to the TMN(Telecommunications Management Network) model which is based on an international telecommunications management standard. We have identified two interfaces in this billing process model. Part 1 of this thesis provides a protocol-independent design of the UAI(Usage Accounting interface) between the service provider and the network provider. Part 2 of this thesis provides information modeling of the UMI(Usage Metering Interface) between the network provider and the equipment provider. This interface is applied to the B-ICI(Broadband ISDN Inter-Carrier Interface) environment.