• Proceedings of the Korean Information Science Society Conference
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• 2001.04a
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• pp.721-723
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• 2001

월드 와이드 웹(WWW)서비스는 상당한 지연이 발생할 것이라고 예상하는 수준까지 성장해 왔다. 이런 이유로 웹 지연시간을 줄이기 위한 기술들이 중요하게 되었다. 프록시 서버 캐시는 느린 응답시간과 네트워크 정체와 같은 문제들을 해결하기 위해서 제안되었는데 이런 프록시 서버들을 계층적으로 구성하는 방법에 대한 많은 연구가 있었다. 하지만 이런 일반적인 웹캐싱 계층 기법들은 프록시 서버들간의 통신 경로에 있어서 유연성을 제공하지 못하는 정적 구조의 기법이다. 이런 정적인 기법에서의 단점을 해결하기 위해서 캐싱 지역 프로토콜(Caching Neighborhood Protocol)이 제안되었고 이 CNP는 요청들을 협력적으로 처리하는 일련의 프록시 서버의 집합이 매 단일 요청에 대해서 바뀔 수 있고 이에 따라서 요청 처리 경로가 다양해 질 수 있기 때문에 정적 구조 기법과는 반대인 동적 구조 기법이다. 하지만 이러한 동적 웹 캐싱 계층 구조인 CNP에서는 각 웹서버를 대표하는 캐싱 대리인(Caching Representatives)에 대한 웹문서의 링크참조정보와 부하정보를 고려하지 않았기 때문에 사용자에게 빠른 응답시간을 제공하지 못하는 단점이 있다. 본 논문에서는 최근에 제안되었던 프록시 서버들을 동적 웹캐싱 계층으로 구성한 CNP와 새로 추가된 C-Rep의 상태정보를 이용해서 새로운 요청 라우팅 기법을 제안하였다. 제안한 기법은 이런 C-Rep의 상태정보를 이용하여 응답시간의 향상과 C-Rep의 부하를 분산시킬 수 있었다.

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.555-562
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• 2002

Increasing of electronic commerce users and high-capacity multimedia data is the main causes of increasing of load and network traffic in electronic commerce system. Increasing of load and network traffic brings the delay of service about client's request. And it's becoming factor that decreases customer satisfaction and corporation's competitive ability. So it is needed to research that consider efficient management and response time of electronic commerce system. In this paper, we designed electronic commerce system based on local server with web cashing function in order to solve load problem of electronic commerce system. And we proposed web cashing algorithm for local web server and analyzed performance by an experiment.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.559-561
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• 2002

고용량 멀티미디어 데이터의 사용 증가와 인터넷 사용 인구의 폭발적인 증가로 현재의 네트워크 인프라로는 사용자의 요구를 충분히 수용하지 못하고 있는 상황이다. 이러한 문제를 해결하기 위해 제시된 웹캐싱 기술도 캐시 서버에 부하가 집중될 때에 지속적인 서비스를 해 주는 것이 불가능한 경우가 발생한다. 본 논문에서는 여러 대의 캐시 서버를 다양한 형태의 가상 캐시 서버로 구축하여 캐시 서버 한 대에 집중되는 부하를 분산하는 방안에 대해서 연구하였다. 이를 위하여 가상 캐시 서버 시스템을 다양한 구성 방식과 알고리즘에 따라 구축하고 성능을 평가하였다. 이런 과정을 거쳐서 멀티미디어 데이터의 스트리밍 서비스에 가장 적합한 구성 및 알고리즘을 제시하였다.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.829-830
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• 2006

A distributed web caching system can transmit information to a user quickly and stably, avoiding a congested internet network by storing and later supplying requested content to a cache that is distributed and shared like a proxy server. This paper proposes a client-based distributed web caching system that assigns an object and controls the load using a user's direct connection to shared caches, without the aid of additional domain name system (DNS) requests. The proposed system simplifies information transmission by reducing both DNS queries and delay time.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.1379-1382
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• 2004

The use of a cache for storing and processing of Web objects is becoming larger. Also, many studies on the efficient management of the storing scope of caches are being done. Web caching algorithms have many differences from traditional algorithms. Particularly, heterogeneity of Web objects that are processing units of Web caching, and a variation of Web object reference characteristic with time are the important causes of the decrease the performance of existing algorithms. In this study, we proposed the new web-caching algorithm. A heterogeneity variation of an object can be reduced as the proposed method dividedly managing Web objects and a cache scope with heterogeneity, and it is adaptively reflecting a variation of object reference characteristics with the flowing of time. In the experiments, we verified that the performance of the proposed method was more improved than existing algorithms through the two experiment models which considered heterogeneity of an object.

• The KIPS Transactions:PartA
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• v.10A no.3
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• pp.261-268
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• 2003

In this paper, we propose a new caching strategy for web servers. The proposed strategy collects only the statistics of the requested file, for example the popularity, when a request arrives. At a point of time, only files with higher forecasted popularity are cached all together. Forecasted popularity based lazy caching (FPLC) strategy uses exponential smoothing method for forecast popularity of web files. And, FPLC strategy shows that the cache hit ratio and the cache transfer ratio are better than those produced by other caching strategy. Furthermore, the experiment that is performed with real log files built from web servers shows our study on forecast method for popularity of web files improves cache efficiency.

• The KIPS Transactions:PartA
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• v.11A no.7 s.91
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• pp.469-474
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• 2004

As traffic on the web increases, users are faced with increasing delays. A key performance measure for the web is the speed with which object is served to users. Web caching is the one of the key method that improve performance of Web base system. Also, many studies for efficient management of storing scope on cache are performed actively. An important issue in web caching is how to improve a efficiency of a caching system. For this, efficient web cache management is required. A solution for this is to set up the caching strategy that consider a heterogeneity of Web object. In this paper, We propose a new web caching technique for a performance improvement of a multimedia object process. The proposed method is based on a heterogeneity of Web object, and it increases performance of a caching system by increasing the caching efficiency of a multimedia object. In the experiment, We verified performance improvement of proposed web caching system through performance analysis of a proposed system.

• The KIPS Transactions:PartB
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• v.11B no.3
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• pp.361-368
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• 2004

This paper proposes an interactive VOD system to serve truly interactive VCR services using multicast delivery, client buffer and web-caching technique which implements the distributed proxy in Head-End- Network(HNET). This technique adopts some caches in the HNET that consists of a Switching Agent(SA), some Head-End-Nodes(HEN) and many clients. In this model, HENs distributively store the requested video under the control of SA. Also, client buffer dynamically expands to support various VCR playback rate. Thus, interactive services are offered with transmitting video streams from network, HENs and stored streams on buffer. Therefore this technique makes the load of network occur In the limited area, minimizes the additional channel allocation from server and restricts the transmission of duplicated video contents

• Journal of Convergence for Information Technology
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• v.9 no.2
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• pp.17-22
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• 2019

Cache is a technique that improves the client's response time, thereby reducing the bandwidth and showing an effective side. However, there are vulnerabilities in the cache technique as well as in some techniques. Web caching is convenient, but it can be exploited by hacking and cause problems. Web cache problems are mainly caused by cache misses and excessive cache line fetch. If the cache miss is high and excessive, the cache will become a vulnerability, causing errors such as transforming the secure data and causing problems for both the client and the system of the user. If the user is aware of the cache infection and the countermeasure against the error, the user will no longer feel the cache error or the problem of the infection occurrence. Therefore, this study proposed countermeasures against four kinds of cache infections and errors, and suggested countermeasures against web cache infections.