• Journal of Broadcast Engineering
• /
• v.23 no.1
• /
• pp.26-35
• /
• 2018

The recent development of overlay network technology enables distributed sharing of various types of contents. Although overlay network has great advantages as a huge content repository, it is practically difficult to directly provide such Internet service as streaming of contents. On the other hand, the media server, which is specialized in content services, has excellent service capabilities, but it suffers from the huge contents that are constantly created and requires large expansion of severs and storages, and thus requires much effort for efficient management of the huge repository. Hence, the association of an overlay network of huge storage with a media server of high performance content service will show a great synergy effect. In this paper, a location-aware scheme of constructing overlay networks and associating it with media server is proposed, and then cache-based contents management and service policy are proposed for efficient content service. The performance is analysed for one of the content services, streaming service.

• Proceedings of the Korean Information Science Society Conference
• /
• 1998.10a
• /
• pp.83-85
• /
• 1998

컴퓨터 하드웨어 기술의 발달은 물론 고속 통신 기술의 발달로 컴퓨터의 사용분야가 단순 계산에서 멀티미디어를 사용하는 VOD 서버 기술을 필요로 하게 되고 경제적이면 효율적으로 멀티미디어 데이터를 다루는 기술이 요구되면서 서버의 확장성과 원활한 데이터 서비스가 필요하게 되었다. 이에 본 논문에서는 초고속 통신망에 기반한 SAN(System Area Network)에 기반한 클러스터링 시스템을 제안하여 최대한 대역폭을 이용한 병렬 I/O를 통하여 SAN 상에 입출력 성능의 개선할 수 있는 Scalable VOD 서버를 제안하여 구현 성능 평가 하혀 한다.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.01a
• /
• pp.69-70
• /
• 2022

본 논문에서는 Photon Network를 사용하여 경찰과 도둑 컨셉으로 5명이 함께 즐길 수 있는 Multi Game을 구현하였다. 서버는 리슨 서버 방식으로 Master Client가 게임을 시작하면 Game에 참가한 모든 Player는 Photon Network의 RPC 기능을 사용하여 Player의 동작, Game 진행 상황 등을 실시간으로 Server에 동기화한다.

• Proceedings of the KSME Conference
• /
• 2003.04a
• /
• pp.792-798
• /
• 2003

This paper is about implementation of intelligent robot based on home network. Existing robots are mainly stand alone type. Home network is spreading rapidly and can play an important role as a path for informations between appliances in home. Robot can be more intelligent and have versatile functions with a junction of home network. By distribution of tasks through home network, robot doesn't have to process every task. In addition, robot can access to appliances through network as appliances are added continuously. In the future, smart space in which robot behaves on various types of network is in expectation. In this research, home network based system which consists of home server, embedded robot, and intelligent robot is proposed and implemented.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.3C
• /
• pp.233-240
• /
• 2012

Unlike traditional factory environment, in an industrial factory network applied wireless sensor network technologies, all procedures of discovery, identification and verification of devices should be performed in an automatic fashion. To address these challenges, we design a management system using the device registry server that we propose in this paper. In the phase of device discovery, the proposed system utilizes properties of routing protocol running in factories. Also, in the phase of identification and verification, the system uses unique and general information of a device stored within the device registration server. Such a way allows management system to reduce implementation complexity and to easily manage devices in a factory applied with a wireless network consisting of heterogeneous devices.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.4B
• /
• pp.424-434
• /
• 2004

Ubiquitous network consists of various devices using several heterogeneous protocols and requires seamless communication between devices. This paper proposes a new hierarchical event service and multiple event server architecture to implement the service under ubiquitous environment. The proposed event service classifies devices by logical and physical location to abstract the idiosyncrasy of used protocols, and reduces network load. Due to the design consideration, the proposed architecture removes transfer of duplicated event data effectively. As a result, we can guarantee the reliable event delivery. The prototype multiple event server architecture was implemented according to the proposed idea and evaluated its performance under a home network test bed.

• Journal of Information Processing Systems
• /
• v.7 no.1
• /
• pp.53-62
• /
• 2011

With the steady growth of mobile technology and applications, demand for more storage in mobile devices has also increased. A lightweight block-level protocol, Internet Advanced Technology Attachment (iATA), has been developed to deliver a cost-effective storage network solution for mobile devices to obtain more storage. This paper seeks to contribute to designing and implementing Load Balancing (LB), Network Monitoring (NM) and Write Replication (WR) modules to improve the protocol's scalability and data availability. LB and NM modules are invoked to collect system resources states and current network status at each associate node (server machine). A dynamic weight factor is calculated based on the collected information and sent to a referral server. The referral server is responsible to analyze and allocate the most ideal node with the least weight to serve the client. With this approach, the client can avoid connecting to a heavily loaded node that may cause delays in subsequent in-band I/O operations. Write replication is applied to the remaining nodes through a WR module by utilizing the Unison file synchronization program. A client initially connected to node IP A for write operations will have no hindrances in executing the relevant read operations at node IP B in new connections. In the worst case scenario of a node crashing, data remain recoverable from other functioning nodes. We have conducted several benchmark tests and our results are evaluated and verified in a later section.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2006.05a
• /
• pp.745-748
• /
• 2006

With a home network, a device can dynamically join a home network, obtain an IP address, convey its capabilities, and learn about the presence and capabilities of other devices. Devices can subsequently communicate with each other directly. Device discovery protocol defines how network services can be discovered on the network. In this paper, we propose the secure discovery method of devices that uses mutual authentication with symmetric key between devices. This method that we present distributes symmetric-key to home network devices by the home server. Using this key, mutual authentication is performed between home appliances. It enables any appliance under any middleware's control to securely communicate any other appliances.

• Journal of Korea Multimedia Society
• /
• v.11 no.10
• /
• pp.1376-1384
• /
• 2008

Numerous researches on network self-configuration have been conducted on Wireless Sensor Network (WSN) and Ad Hoc network but the results have not been applied yet for factory automation. This paper presents development of intelligent process management systems conducting process monitoring and control irrelevant to physical position of a plant operator. The systems are indispensable for diagnosis of rotating machines which cannot exploit wired network. The system was implemented in a Personal Digital Assistant (PDA) using Bluetooth communication protocol. When a mobile terminal reaches to communication range of the process management server, the server detects the mobile terminal to reconfigure plant network automatically. The server authenticates a user of the terminal to download and installs monitoring and control program considering authorized level of the user. If the terminal leaves communication range of the server, it deletes the node from the network and removes the program automatically to save resources and prevent security problems such as missing terminal. Operation of developed functions was verified in a testbed emulating steel-making plant.

• Journal of the Korea Society of Computer and Information
• /
• v.7 no.4
• /
• pp.141-149
• /
• 2002

Recently, a number of network systems are developed rapidly and network architectures are more complex than before, and a policy-based network management should be used in network system. Especially, a new paradigm that policy-based network management can be applied for the network security is raised. A security policy server in the management layer can generate new policy, delete. update the existing policy and decide the policy when security policy is requested. The security server needs to analyze and manage the alert message received from server Policy enforcement system in the enforcement layer for the available information. In this paper, we implement an alert analyzer that analyze the stored alert data for making of security policy efficiently in framework of the policy-based network security management. We also propose a data mining system for the analysis of alert data The implemented mining system supports alert analyzer and the high level analyzer efficiently for the security.