• Journal of Institute of Control, Robotics and Systems
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• v.20 no.7
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• pp.782-787
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• 2014

Due to the complicated steel structure and safety concern, it is very difficult to deploy wireless networks in power plants. This paper presents a hybrid network, named as $P^2HYMN$ (Power Plant HYbrid Maintenance Network), encompassing PLC (Power Line Communication), TLC (Telephone Line Communication), and Wireless LAN. The design goal of $P^2HYMN$ is to integrate multimedia data such as design drawings of control equipment, process data, and video image data for maintenance operation in electric power plants. A Multiplex Line Communication (MLC) device was designed and implemented to integrate PLC, TLC, and Wireless LAN into $P^2HYMN$. Performance test of $P^2HYMN$ has been conducted on a testbed under various conditions. The throughput of TLC was shown as 39 Mbps. Because the bandwidth requirement per camera is 8.5 Mbps on average, TLC is expected to support more thant four video camera at the same time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.11
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• pp.1216-1223
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• 2014

Internet traffic is rapidly increasing due to the spread of personal smart devices and the demand for multimedia contents. When designing a large ship such as cruise, network architecture is also considered which supports various IT services in a maritime environment similar to the ground environment. In this paper, we consider wireless P2P (peer-to-peer) communication for efficient multimedia content sharing and propose novel handover scheme for efficient download service. The proposed handover method shows that it can improve the download symbol rates for handover in a wireless P2P system considering the signal strength and quality of peers as well. The proposed system is expected to provide efficient contents distribution and reliable communication in the ship-area-network (SAN).

• Journal of Communications and Networks
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• v.11 no.4
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• pp.359-367
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• 2009

Trust-based solutions provide some form of payment to peers to encourage good behavior. The problem with trust management systems is that they require prior knowledge to work. In other words, peers are vulnerable to attack if they do not have knowledge or correct knowledge of other peers in a trust management system. Therefore, considering only trust is inadequate when a decision is made to identify the best set of peers to utilize. In order to solve the problem, we propose a distributed decision-making mechanism for wireless peer-to-peer (P2P) networks based on game theory and relevant trust mechanisms in which we incorporate the element of trust and risk into a single model. The main idea of our mechanism is to use utility function to express the relationship between benefits and costs of peers, and then make the decision based on expected utility as well as risk attitude in a fully distributed fashion. The unique feature of our mechanism is that it not only helps a peer to select its partners, but also mitigates vulnerabilities in trust-based mechanisms. Through analysis and experiments, we believe our approach is useful for peers to make the decision regarding who to interact with. In addition, it is also a good starting point for exploring tradeoffs among risk, trust and utility.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.4
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• pp.501-509
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• 2014

In NCW(Network Centric Warfare) environment, mobile nodes communicate through wireless link. But wireless link provides limited networking performance due to signal interferences or mobility of nodes. So it is quite challenge to acquire enough networking resources and use the resources efficiently. In this paper, we have proposed a P2P based tactical information sharing system which provides satisfactory visual information playout for mobile nodes(i.e., military personnel, vehicle,..) in NCW environment. Our proposed system consists of two components. One is caching-enabled switch which stores tactical information segments at its internal storage and then transports them to mobile nodes when require. Another is centralized scheduling algorithm which exploits networking resources more efficiently. To validate performance of proposed system, we performed series of experiments in wireless network testbed. Results show improved performance in terms of segment-missing ratio, networking resources usage, sharing time, and number of simultaneous playout mobile nodes with acceptable playout continuity(i.e., over 95%).

• 한국정보컨버전스학회:학술대회논문집
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• 2008.06a
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• pp.195-198
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• 2008

The JXTA was made in order to solve the problem of being generated with the computer platform suggested with the P2P(Peer-to-peer) method in the distributed computing. JXTA makes a communication between the various network and the devices is connected to a network which possible. It was designed to the client having the minimum computing ability could attend in the peer-to-peer network. However, for smoothly applying JXTA in the wireless environment, there is a limit with the limited resource of the Mobile Device. By using the Relay of the JXTA based for the Mobile Device, this paper implemented the P2P service which is flexibly effective in the wireless network environment.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.941-944
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• 2003

본 논문에서는 유무선 통합 망에서 미디어 파일과 같은 자원들을 효율적으로 공유하기 위해, 이동 에이전트 기능을 사용하여 P2P 플랫폼을 설계하였다. 현재 대다수의 P2P 애플리케이션들은 유선망을 기반으로, 서로 다른 API를 사용하고 있어, 플랫폼에 종속적이며, 다양한 네트워크 환경과 디바이스 등을 포함하지 않는다. 이러한 문제점을 해결하기 위해 오픈 소스 프로젝트인 썬의 JXTA를 이용하여 전체 시스템을 설계하였으며, 기존의 JXTA 프로토콜의 문제점을 모바일 에이전트를 이용해 개선하고자 한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.655-658
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• 2003

본 논문에서는 기존의 유선망을 기반으로 하는 P2P 시스템에 썬의 JXTA와 JXME를 이용하여 모바일 기능을 추가하였으며, 유무선 통합 망에서 미디어 파일과 같은 자원들을 효율적으로 공유하도록 설계하였다 현재 대다수의 P2P 애플리케이션들은 유선망을 기반으로, 서로 다른 API를 사용하고 있어, 플랫폼에 종속적이며, 다양한 네트워크 환경과 디바이스 등을 포항하지 않는다. 이러한 문제점을 오픈 소스 프로젝트인 썬의 JXTA를 이용하여 전체 시스템을 설계하였으며, JXTA 프로토콜을 이용하여, 피어의 상태 정보를 모니터링하여, 원격 피어의 상태에 따라 동일한 파일을 설러 피어들로부터 전송 받을 수 있도록 한다.

• Journal of KIISE:Information Networking
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• v.33 no.2
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• pp.139-148
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• 2006

Recently with the advancement of local wireless communication technologies, digital trends of audio contents and devices are paving the way for new experiences to network-based audio streaming services. In this paper, we present the Wireless Audio Sharing (WASH) technology over Bluetooth and Wireless Local Area Network (WLAN). WASH system provides an audio sharing mechanism over multiple users and also provides stereo audio streaming between Bluetooth-enabled devices and Universal Plug and Play (UPnP) media devices connected to wired/wireless LANs. To achieve these, we extended the Bluetooth audio distribution profile and combined the extended profile with the UPnP AV architecture. With the implementation of this WASH technology, we show some experimental results of the stereo audio streaming in a real environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.568-570
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• 2013

NFC represents the 2nd generation of the proximity contact-less technology, which beyond the RFID, supports peer-to-peer communication, and enables consumer access to aggregated services, anytime, anywhere, with any type of consumer stationary and mobile devices. NFC is a short range device wireless technology designed to exchange data, initiate connections with other wireless networks and act as a secured smart key for access to services such as cashless payment, ticketing, on-line entertainment and access control. In this paper, the NFC services for social networking applications are studied, and the signal flow of SNS application based on NFC P2P for smart devices and server model is proposed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.3
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• pp.815-834
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• 2012

Recently, along with the innovative development of wireless communication techniques and mobile devices, mobile P2P services in mobile wireless networks have gained a lot of attention. In this paper, we propose a resource discovery scheme with data dissemination over mobile P2P networks. In the proposed scheme, each peer manages a local information table, a resource index table, and a routing table in a local database to enhance the accuracy and cost of resource discovery. The local information table stores the status of a mobile peer, and the resource index table stores the resource information of the neighbor peers via the ranking function. The routing table is used to communicate with the neighbor peers. We use a timestamp message to determine whether or not the resource index table will be changed before the resource information is exchanged. Our ranking function considers the interest and mobility of the mobile peer and prioritizes the resource information transmitted from the neighbor peers. It is shown via various experiments that the proposed scheme outperforms the existing scheme.