• Review of KIISC
• /
• v.14 no.4
• /
• pp.10-18
• /
• 2004

상호운영성, 유연성, P2P(피어투피어), 역동성, 확장성 등 웹 서비스가 지닌 다양한 특성으로 인하여 웹 서비스 보안은 안전한 웹 서비스 운영을 위한 핵심요소라 할 수 있다. 웹 서비스의 기본 구성은 서비스 수요자와 제공자, 검색소로 구성되며 WSDL(Web Service Definition Language), UDDI(University Discovery and Integration of Business for Web), SOAP(Smple Object Access Protocol)등 세 개의 표준으로 서비스는 이루어진다. 이 중에서 특히 메시지 교환을 담당하는 통신 프로토콜인 SOAP는 웹 서비스 보안의 중심에 있으며, 웹 서비스 보안은 SOAP 메시지의 사용자 인증과 무결성, 기밀성을 보장하는 것으로 정의할 수 있다. SOAP는 HTTP를 통해 일반적으로 전송되므로 HTTP 상의 모든 위협을 가지게 되며 전송계층에 기반을 둔 보안을 생각할 수 있지만, 사실상 웹 서비스는 다수의 중간 중개자를 가질 수 있는 구조이기 때문에 단대단 보안(메시지 레벨의 보안)이 반드시 필요하다. 또한, 웹 서비스 상에서 단대단 보안을 보장하기 위해서는 각 객체와 키와의 연결이 중요하며 특정 객체에게 발행한 보안토큰의 신뢰성 화보를 위한 메카니즘을 필요로 한다. 본 논문에서는 이러한 보안 요구사항을 만족하기 위하여 XML 메시지 보안을 위한 전자서명 및 암호화 표준과 SOAP을 위한 W3C, OASIS의 통합표준을 중심으로 SOAP 메시지 보안기술을 분석하고자 한다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2019.07a
• /
• pp.343-344
• /
• 2019

본 논문에서는 교수자에게 큰 부담을 주지 않으면서 학습 효과를 높이기 위한 방법으로 문제풀이 기반의 자발적 복습을 지원하는 교수학습 모형을 제안하고 이를 수업 운영에 적용하였다. 학습자들에게 배포한 수업내용을 복습할 수 있는 문제들로 구성한 유인물은 단순히 해당 요일의 수업을 되풀이하여 익히는 소극적 의미에서의 복습이 아니라 이전 수업 내용들 간의 연관성을 이해할 수 있도록 문제를 구성하고 학습자들의 복습시 발생하는 어려움을 해결할 수 있도록 교수 전략을 수립한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 1999.10c
• /
• pp.739-741
• /
• 1999

공동작업을 위한 어플리케이션 공유는 여러 시스템에 분산되어 있는 개발도구와 어플리케이션을 공유하여 다수의 참여자가 공간적으로 제약받지 않고 공동 개발할 수 있도록 한다. 그러나 가상공간에 개념을 둔 CSCW에 기존의 어플리케이션 공유 방식을 적용하기에는 3차원이라는 공간적인 요소를 고려하지 않은 문제점을 가지게 된다. 또한 기존의 CSCW에 비해서 가상공간에 기반을 둔 CSCW 어플리케이션 개발은 가상 공간과 다중 참여자를 고려해서 개발하여야 하기 때문에 개발자에게 매우 어려운 작업이다. 따라서, 이 논문에서는 다중 참여자를 지원하는 VRML 기반 어플리케이션 공유 엔진을 설계하였다. 설계된 VRML 기반 어플리케이션 공유 엔진은 참여자 사이트로 에이전트를 이동시켜 웹 브라우져 내의 VRML 가상 공간에서 참여자의 어플리케이션 대한 3차원상의 이벤트를 2차원적인 상대값으로 바꾸고 실제 어플리케이션상의 이벤트로 변환하는 메커니즘을 도입하여 VRML 가상공간에서 어플리케이션을 공유를 가능하게 하였다. 또한 참여자 이벤트를 처리하는 스케줄러를 도입하여 참여자의 이벤트를 순서적이고 참여자 간의 충돌을 해결할 수 있었으며 가상환경이 VRML로 구성되기 때문에 운영체제에 독립적이고 웹상에서 어플리케이션 공유가 가능하였다. 그리고 가상환경을 위한 CSCW 응용 개발에 대한 오버헤드를 줄이고 기존 윈도우 어플리케이션을 가상공간에 사용함으로서 기존 어플리케이션의 재사용성을 높일 수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.5B
• /
• pp.421-429
• /
• 2006

In this paper, we suggest a new capability aware spanning tree(CAST) algorithm for Ethernet bridged network which consists of both legacy Ethernet bridges and synchronous Ethernet ones. The legacy spanning tree algorithm specified in IEEE 802.1D standard select root bridge and construct tree based on each bridge's identifier without consideration of each bridge's capability. Thus we note that if the legacy STP may assign a synchronous bridge as a root bridge, the bridge may become a bottleneck for asynchronous trafficbecause of bandwidth limitation for asynchronous traffic. In this paper, the CAST algorithm constructsmultiple spanning tree by using of bridge capability and makes different transmission path for each traffics, can removes this kind of defect. From the simulation results, we can see that the proposed CAST algorithm has better end-to-end delay performance than legacy spanning tree algorithm in high traffic load and multiple hops environment.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.6
• /
• pp.1025-1030
• /
• 2019

This paper describes SON(: Self Organization Network) technology in LTE networks. The SON is a unique feature of LTE compared to previous cellular systems such as UMTS and GSM, and it is a tool that effectively derives the best performance in the time-varying wireless radio environment. Also, the SON has the ability for the operator to automate the setting of the network, allowing for centralized planning and reducing the need for manual work. The SON is largely divided into three categories: Self-Configuration, Self-Optimization, and Self-Healing. Each large categories has a detailed description of technology, and the technologies in each categories are gathered to complete the technology called the SON. In this paper, we focus on MRO which is one of the Self-Optimization technique in each of the three categories.

• Journal of KIISE:Software and Applications
• /
• v.41 no.7
• /
• pp.457-468
• /
• 2014

Recently, several approaches are proposed to support developing Self-Adaptive System. However, they do not provide the way to accept interaction between requirements and architecture. It makes difficult to judge the impact of changing requirements, handle quickly, and understand adaptation process for stakeholder. To overcome above problems, this paper suggests the interweaving method for providing traceability based on the relationship between requirements and architecture. This traceability allows tracing the impact of changing requirements, and it provides the rationale of architectural decision for advanced degree of understanding. Example shows the usefulness through developing process and changing process on Smart Grid domain.

• The Journal of the Korea Contents Association
• /
• v.6 no.3
• /
• pp.108-115
• /
• 2006

e-Learning contents are composed of compounding multimedia data. It requires many professionals in contents development stage. The process of e-learning contents development can be seen as a collaborative work. In the perspective of a collaborative work process, the whole process of e-learning contents development would be regarded as collaborative work process for each participant as well as for whole group members. Most of collaborative works in contents development field are widely distributed. Members of work groups require workspaces for sharing information and communicating each other. In addition to workspaces, it also needs to support collaborative reflection such as planning for collaborative work and monitoring for work process. This paper is intended to develop the reflective collaborative work system for e-Learning contents development in order to support the systemic process of e-learning contents development. The reflective collaborative work system is composed of four supportive parts: work flow management, personal workspace, collaborative workspace, and collaborative reflection.

• The Journal of the Korea Contents Association
• /
• v.19 no.4
• /
• pp.197-206
• /
• 2019

This study aims to analyze through the integrated textbooks whether writing tasks are designed to be successful in cultivating students' writing abilities in the general-purpose Korean language education. First, we established the concept and the components of the writing task based on the definitions mentioned in previous research. The analysis of the types of writing tasks revealed "free writing" and "imitation and writing" to be the most frequent types of writing tasks in both textbooks. The textbooks have only twenty-one subjects in common. And most instructions provide only themes and genres, excluding the purpose, form, quantity, and time necessary for the article or for comprehending the instructions. In these tasks, the reading passages are most often explanatory text. The scoring criteria and time were not provided for the evaluation criteria and other factors. Therefore it became necessary to express the components of the writing task as explicitly and concretely as possible to improve learners' performances.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.6
• /
• pp.137-145
• /
• 2008

In general, a large-scale wireless sensor network(WSNs) is composed of hundreds of or thousands of sensor nodes. In this large-scale wireless sensor networks, it is required to maintain and manage the networks to lower management cost and obtain high energy efficiency. Users should be provided with sensing service at the level of quality for users through an efficient system. In evaluating the result data quality provided from this network to users, the number of sensors related to event detection has an important role. Accordingly, the network protocol which can provide proper QoS at the level of users demanding quality should be designed in a way such that the overall system function has not to be influenced even if some sensor nodes are in error. The energy consumption is minimized at the same time. The protocol suggested in this article is based on the LEACH protocol and is a role-based self-Organization one that is appropriate for large-scale networks which need constant monitoring.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.6
• /
• pp.225-230
• /
• 2016

Recently, Web has arisen large amount of data that to the development of the network and the Internet. In order to process it appeared that Big Data technology. Big Data technologies have been studied aiming a multifaceted and accurate analysis using existing regular data and a variety of data social data. But social data does not have the expertise and objectivity. And such manipulation and concealment and distortion of information have been raised troubling. Thus, this paper proposes for trust big data platform and will be described in detail. The big data platform proposed in this paper consists of data refiner, Data Analyzer, co-truster, visualizer, searcher, etc.