• Proceedings of the Korea Multimedia Society Conference
• /
• 2003.05b
• /
• pp.655-658
• /
• 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:Computing Practices and Letters
• /
• v.16 no.2
• /
• pp.217-221
• /
• 2010

As the appearances of various new mobile devices and the explosive growth of mobile device users, many researches related to mobile P2P systems have been proceeded actively. In this paper, we propose a new search algorithm for the double-layered super peer system in the mobile environment. For the proposed search algorithm, we divide the entire experiment region into a grid of cells, each of which has the same size. The grid is configured properly by considering the communication range of a mobile device and the number of peers in the system. The proposed search algorithm is a partial flooding search method based on the directions of cells involved with the search. It reduces successfully the network traffic, but shows a low search hit ratio. To enhance the search hit ratio, we introduce a bridge-peer table for a super peer and utilize an n-way search. The experimental results show that the proposed algorithm made an average of 20~30% reduction in the number of message packets over the double-layered system. The success ratio was also improved about 2~5% over the double-layered system.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.7B
• /
• pp.728-733
• /
• 2009

An ubiquitous environment has features like peer-to-peer and nomadic environments. Such features can be represented by peer-to-peer systems and mobile ad-hoc networks. P2P systems and MANETs share similar features, appealing for implementing P2P systems in MANET environment. However, if a P2P system designed for wired networks was applied to mobile ad-hoc environment, its performance was not good enough. Subsequently, this paper proposes a P2P system to improve performance using cross-layer design and the goodness of a node as a peer by using routing metric and P2P metric to choose favorable peers to connect. It also utilizes proactive approach for distributing peer information. The simulation results showed that the proposed system produced better performance in query success rate, query response time and energy consumption by reducing the routing path length.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.280-282
• /
• 2015

This paper proposed Small business owners can use customer contact without additional external assistance professionals and mobile apps, the mobile web, homepage is can automatically create. Automation Platform system combines Single Page Application, cross-platform based native mobile apps, N-Screen based Content building, private cloud based PaaS of construction technology, P2P file sharing and network based multimedia-threaded technology and by automated platform to study how a small business to communicate with customers easily.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2019.05a
• /
• pp.290-292
• /
• 2019

Since the advent of blockchain and bitcoin, decentralization has been accelerating around the world as a public blockchain ethereum with smartcontract has begun. Developers can use Ethereum's blockchain development platform to develop "distributed applications" (DApp) running on a decentralized P2P network, and various types of devices from IoT to mobile can participate in a block-chain distributed environment have. Using Ethereum's blockchain development platform, developers can develop "Decentralized Application (DApp)" that run on a decentralized P2P network and various types of devices from IOT to mobile can participate in distributed blockchain environments. There are many ways to interact with the blockchain and the smart contract, but users tend to prefer the mobile methods due to their convenience and accessibility advantages. Therefore, the author developed an Android based voting DApp and researched related issues. Since the current development methods of DApp are not adequately researched and standardized, efficient methods for developing user-friendly DApp were studied. Because DApp has to spend a certain amount of fees to interact with blockchain, it has intensively investigated the gas problem of Smart Contract code and the security problem of code, and author would like to introduce it in this paper.

• 한국정보통신설비학회:학술대회논문집
• /
• 2003.08a
• /
• pp.329-331
• /
• 2003

본 논문에서는 통합 및 유비퀴터스(Ubiquitous) 환경의 실현을 위한 첫 단계 서비스라 할 수 있는 모발일 홈 네트워크 서비스에 대해 살펴본다. 따라서 모바일 홈 네트워크(mobile Home Network, mHN) 서비스의 개념 및 이를 제공하기 위해 존재하는 가치사슬, 서비스 모델 및 필요기술 등을 제시한다. 본 논문에서는 서비스 모델을 크게 P2P, Semi P2P, 통합형 (Hub & Spoke)으로 구분하여 각 모델의 특징을 살펴본다. 특히, 통합형 모델을 위한 서버의 서비스, 제어 및 관리 기능과 관련 노드들과의 연동을 위한 인터페이스 등을 나타낸다. 뿐만 아니라 댁내와 댁내의 연결 노드인 홈 게이트웨이의 구조 및 기능 들을 살펴보고 마지막으로 다양한 모바일 홈 네트워크 서비스의 예를 제시한다.

• Convergence Security Journal
• /
• v.21 no.1
• /
• pp.121-127
• /
• 2021

MANET, which does not have any infrastructure other than wireless nodes, has the advantage of being able to construct a fast network. However, the movement of nodes and wireless media are also the causes of security vulnerabilities of MANET. In particular, the damage caused by the attacking nodes existing on the network is considerably greater than that of other networks. Therefore, it is necessary to detection technique for attacking nodes and techniques to reduce damage caused by attacks. In this paper, we proposed a hierarchical structure technique to increase the efficiency of intrusion detection and collaboration-based intrusion detection technique applying a P2P mesh network configuration technique to reduce damage caused by attacks. There was excluded the network participation of the attacking node in advance through the reliability evaluation of the nodes in the cluster. In addition, when an attack by an attacking node is detected, this paper was applied a method of minimizing the damage of the attacking node by transmitting quickly the attack node information to the global network through the P2P mesh network between cluster heads. The ns-2 simulator was used to evaluate the performance of the proposed technique, and the excellent performance of the proposed technique was confirmed through comparative experiments.

• Journal of Advanced Navigation Technology
• /
• v.15 no.3
• /
• pp.364-371
• /
• 2011

In P2P distribution mobile networks, QoS of streaming media services are under heavy influence from overheads such as congestion, latency, and interference. The problem is further complicated by the fact that the popularity of media objects changes over time. This paper proposes a new FSMS+ (Fuzzy Similarity-based Multi-level Streaming Scheme) which minimizes performance degradation of streaming services due to overhead. We then utilize fuzzy similarity-based relevance that can dynamically stream the streaming media object with minimum overhead. The simulation result showed that the proposed scheme has better performance in retransmission rate, congestion control rate and latency rate than the other existing methods of distance method, DC (disk caching) method, and prefix method.

• Journal of Digital Convergence
• /
• v.12 no.2
• /
• pp.335-341
• /
• 2014

To play the networked video contents in a client's mobile device in real time, the contents should be delivered to it by the contents server with streaming technology. Generally, in a server-client based commerce model, the server is in charge of both the authentication of the paid customer and distribution of the contents. The drawback of it is that if the customers' requests go on growing rapidly, the service quality would be degraded results from the problems of overloaded server or restricted network bandwidth. On the contrary, in P2P based networks, more and more the demand for service increasing, the service quality is upgraded since a customer can act as a server. But, in the P2P based network, there are too many servers to manage, it's possible to distribute illegal contents because the P2P protocol cannot control distributed servers. Thus, it's not suitable for commercial purposes. In this paper, the dymanic group authentication scheme is proposed which is suited to P2P based applications. The proposed scheme consists of group based key generation, key update, signature generation and verification protocols. It can control the seeder's state whether the seeder is joining or leaving the network, and it can be applied to hybrid P2P based commerce model where sales transactions are covered by the index server and the contents are distributed by the P2P protocol.

• Journal of Advanced Navigation Technology
• /
• v.15 no.6
• /
• pp.1015-1024
• /
• 2011

Mobile P2P protocols in ad-hoc networks have gained large attention recently. Although there has been much research on P2P algorithms for wired networks, existing P2P protocols are not suitable for mobile ad-hoc networks because they do not consider mobility of peers. This study proposes a new cluster-based P2P protocol for ad hoc networks which utilizes peer mobility. In typical cluster-based P2P algorithms, each cluster has a super peer and other peers of the cluster register their file list to the super peer. High mobility peers would cause a lot of file list registration traffic because they hand-off between clusters frequently. In the proposed scheme, while peers with low mobility behave in the same way as the peers of the typical cluster-based P2P schemes, peers with high mobility behave differently. They inform their entrance to the cluster region to the super peer but they do not register their file list to the super peer. When a peer wishes to find a file, it first searches the registered file list of the super peer and if fails, query message is broadcasted. We perform mathematical modeling, analysis and optimization of the proposed scheme regarding P2P traffic and associated routing traffic. Numerical results show that the proposed scheme performs much better than or similar to the typical cluster-based P2P scheme and flooding based Gnutella.