• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.3
• /
• pp.1260-1283
• /
• 2019

Low earth orbit (LEO) satellite broadband network is a crucial part of the space information network. LEO satellite constellation design is a top-level design, which plays a decisive role in the overall performance of the LEO satellite network. However, the existing works on constellation design mainly focus on the coverage criterion and rarely take network performance into the design process. In this article, we develop a unified framework for constellation optimization design in LEO satellite broadband networks. Several design criteria including network performance and coverage capability are combined into the design process. Firstly, the quality of service (QoS) metrics is presented to evaluate the performance of the LEO satellite broadband network. Also, we propose a network stability model for the rapid change of the satellite network topology. Besides, a mathematical model of constellation optimization design is formulated by considering the network cost-efficiency and stability. Then, an optimization algorithm based on non-dominated sorting genetic algorithm-II (NSGA-II) is provided for the problem of constellation design. Finally, the proposed method is further evaluated through numerical simulations. Simulation results validate the proposed method and show that it is an efficient and effective approach for solving the problem of constellation design in LEO satellite broadband networks.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 1996.06b
• /
• pp.101-106
• /
• 1996

This paper describes the system and network configurations of the Application Development Center for multimedia applications on Korean broadband testbed network. The center is primarily used for developing networked multimedia services funded by the Korean Ministry of Information and Communications. The center is quipped with ATM switch, multimedia workstations and PCs. More than 180 applications for the broadband testbed network are under development. Several examples will be presented in detail.

• Information Systems Review
• /
• v.6 no.2
• /
• pp.1-24
• /
• 2004

This paper develops a framework for analyzing the effectiveness of broadband network from the value chain view. The value chain of broadband network is composed of activities such as broadband network building, application/equipments development, information systems utilization. The effectiveness from the interaction between these activities are defined as the effectiveness of informatization(private and public sector) and the effectiveness of IT Industry(effects on production on inducement of broadband carriers, IT equipments and service market creation, online digital contents market creation). For testing its real-world applicability, a case study is performed on the broadband network of Korea and the effectiveness of the framework for analyzing the effectiveness of broadband network is demonstrated.

• ETRI Journal
• /
• v.26 no.5
• /
• pp.505-508
• /
• 2004

We propose a new arbitration method for an input buffered switch with a buffered crossbar. In the proposed method, an exhaustive polling method is used to decrease the synchronization. Using an approximate analysis, we explain how the proposed method improves the switch performance. Also, using computer simulations, we show the proposed method outperforms the previous methods under burst traffic.

• ETRI Journal
• /
• v.27 no.1
• /
• pp.110-113
• /
• 2005

The resilient packet ring (RPR) is a data optimized ring network, where one of the key issues is on load balancing for competing streams of elastic traffic. This paper suggests three efficient traffic loading algorithms on the RPR. For the algorithms, we evaluate their efficiency via analysis or simulation.

• Journal of Communications and Networks
• /
• v.8 no.4
• /
• pp.410-421
• /
• 2006

In this work, we propose an analytic framework for dimensioning the link capacity of broadband access networks which provide universal broadband access services to a diverse kind of customers such as patient and impatient customers. The proposed framework takes into account the flow-level quality of service (QoS) of a connection as well as the packet-level QoS, via which a simple and systematic provisioning and operation of the network are provided. To that purpose, we first discuss the necessity of flow-aware network dimensioning by reviewing the networking technologies of the current and future access network. Next, we propose an analytic model for dimensioning the link capacity for an access node of broadband convergence networks which takes into account both the flow and packet level QoS requirements. By carrying out extensive numerical experiment for the proposed model assuming typical parameters that represent real network environment, the validity of the proposed method is assessed.

• International journal of advanced smart convergence
• /
• v.4 no.2
• /
• pp.14-19
• /
• 2015

Recently, water sewage disposal facilities are able to manage real-time data collection and record management through compact broadband modem LAN switching technology. Therefore, it needs more stable and efficient facility management. So, we required practical use of environmental facilities convergence based on broadband integrated modem. In this paper, we proposed short distance wireless communication network of compact broadband modem for sewage disposal facilities. And it received data inside of water treatment facility using the two communication methods (IEEE802.11x and IEEE802.15.4x). Then, our proposed an data-flow control algorithm of wireless network technology will prioritize processing data when emergency happen through collecting data, analysis data and processing. Lastly, we proved usefulness by experiment and simulation analysis.

• Journal of Digital Convergence
• /
• v.13 no.12
• /
• pp.13-21
• /
• 2015

Ongoing advances in wireless broadband technologies can affect all of industrial society. As new wireless broadband technologies emerge, they will improve competition between established industries and their current services and produce new industries and new converged services. This paper analyzes the trend of next-generation wireless broadband and suggests ways of activating the industry further. To this end, we analyze the trend for previous wireless broadband industries and find out three influential factors (content, wireless network technology, and service) that will produce the continued growth of wireless broadband. Using these three factors, we propose a network technology-driven growth model. Based on that model, we offer activation plans for next-generation wireless broadband industries. This study thus provides an insightful perspective for next-generation wireless broadband industries by establishing additional useful guidelines for developing wireless broadband industries in the future.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.24 no.8
• /
• pp.860-872
• /
• 2013

In this paper, reasonable and effective building strategies of PPDR network is presented through investigating and analysing current policies for PPDR network of Korea and foreign countries. The research result shows that it is necessary PPDR network is designed and implemented considering currently transient status in aspects of PPDR-related technical roadmaps and existing PPDR networks. Also, in the transient period of more than 5 years, mobile broadband- based private PPDR network should be builded and it should be complemented by some commercial networks such as TRS or other mobile broadband networks.

• Journal of the Korea Society of Computer and Information
• /
• v.23 no.9
• /
• pp.51-56
• /
• 2018

Currently, many households raise their companion animals for personal reasons. In this environment, the companion animal is left alone in the home, the owner of the companion animal is increasingly curious about the behavior pattern of the companion animal left alone, and there are many devices that can solve this question. In this paper, we have designed and implemented a Bluetooth-based slave device (beacon in this paper) and a router capable of connecting to a broadband network that can observe behavior patterns of companion animals by using advanced ICT technology. The Bluetooth router designed and implemented in this paper installs a beacon in the home, receives the beacon signal from the device and the beacon installed by the companion animal, and transmits the moving line of the companion animal to the owner of the companion animal through the broadband network, so that it can be confirmed in real time through the app for the provided smart phone.