Earticle

There have been researches into digital watermarking technology or Fingerprinting vigorously to safeguard 'Protective rights for knowledge and poverty' for digital contents. DRM, Digital Rights Management, is not only 'Protective rights for knowledge and poverty', but also management and systems that are necessary to put out, circulate and use for contents. This technology, DRM, encrypts contents to protect digital contents and they are sold users on. Sellers transmit contents with 'Usage Right' and a license including a key of encryption. The key of encryption decodes encoded files. The right of usage restricts users' application of contents. Even if digital contents that are applied the DRM are coped illegally and circulated, contents will be protected from that because a player of DRM checks existence of licenses and allows contents to be restored. However, this method might cause users to feel inconvenient since the users can only restore contents through the licenses offered by a player or a Smartcard. If radio as well as cable is used popularly in the future, there will be a lot of limits to use those kinds of players. In the method of that, the method using players need different players in order to work successfully in wired and wireless environment. In the case of using Smartcards, there might be a dangerous situation when the Smartcards disappeared. This paper proposes two kinds of ideas. One is protecting contents from illegal acts such as illegal copies when the contents are in the process of circulation. The other is the protocol that can give users convenience. Hidden Agents are used so that contents are protected from illegal copies and illegal use in the contents and cuts off those illegal acts. The Agent will be installed without any special setup. In addition, it can replace roles of Watermarking as a protection. Therefore, this paper shows the solution of illegal copies that happens frequently.

Abstract. IMT-2000 appeared in order to satisfy the desires of the uses who wish to supply through wireless most of the services being provided through wire, such as Internet services and multimedia high-speed data information.[1] However, during global roaming, the signal data and the user data get transmitted through the networks of other users. Also, it is judged that with the provision of high speed data communication the amount of data communication necessary for confidentiality protection will increase. It is planned that the recent IMT-2000 project will begin its commercial service in 2002. From this viewpoint, wireless contents, due to their special characteristics, are greatly exposed to illegal actions by third persons. As a result, it can be said that security and authentication issues in the mobile telecommunication environment are indispensable matters. For this purpose, it is intended that in this thesis through an analysis of the existent IMT-2000 authentication method, a more safe and efficient authentication method is presented and, at the same time, a security protocol necessary in the provision of wireless contents is designed.

This paper describes an efficient audio flow control method in the point of quantitative performance using TDM(Tree-structural Distributed-terminal Mixing), compared to existing P2P(Peer To Peer) method. In comparison with existing P2P method, using central mixing and distributed terminal mixing method, we achieved advance at the point of global network usage and each terminal's CPU load, and additionally we expect more session, more terminal can be served by same amount of network bandwidth and computers. By using P2P method in audio communication, speaker and listener must connect to each other. So it has the critical defect that as the participants grows more and more, the network bandwidth usage, each terminal's CPU load will grows rapidly. So the number of participants in same session will be extremely restricted. In comparison with P2P method, the central mixing method has the great advantage at the points of network usage and terminals CPU load. Regardless of the number of speakers and listeners, all the participants can speak and listen with all other participants by using just one stream's amount of data size and CPU load. But all the network usages and CPU loads of "Audio decompression->Buffering->Mixing->Audio Compression" are concentrated on central server. So the number of sessions and terminals can be participated in one server will be highly restricted. This study solves the problems of server's CPU load and network load by using TDM. The TDM is the method to distribute the overload for gathering, mixing and distributing the audio data according to each terminal’s up/down bandwidth and data processing capability using tree-structure. This method enables many terminals participate in the internet-broadcasting by distributing the overload of server to all the terminals.

Accurate system sizing are essential for higher efficiency of investment. Accurate system sizing benefits are generally viewed in terms of the avoidance of excess equipment and lost opportunity costs by not being able to support business needs. We are proposed calculating method for hardware components that is CPU, memory and system, data disk according to the application system types

From the 90's, the image information retrieval methods have been on progress. As good examples of the methods, Conventional histogram method and merged-color histogram method were introduced. They could get good result in image retrieval. However, Conventional histogram method has disadvantages if the histogram is shifted as a result of intensity change. Merged-color histogram, also, causes more process so, it needs more time to retrieve images. In this paper, we propose an improved new method using Adaptive Color Histogram (ACH) in image retrieval. The proposed method has been tested and verified through a number of simulations using hundreds of images in a database. The simulation results have quickly yielded the highly accurate candidate images in comparison to other retrieval methods. We show that ACH's can give superior results to color histograms for image retrieval.