• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4B
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• pp.687-694
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• 2010

IPTV(Internet Protocol Television) is an emerging technology in which telecommunication and broadcasting technologies are converged. IPTV service providers usually multicast scrambled contents. And only legitimate subscribers who pass the access control can de-scramble and use the contents. In order to ensure revenues, providers oftentimes employ password-based authentication protocols that ensure secure authentication processes between set-top box and smart card. In this paper, we propose a fingerprint-based 1-out-of-n authentication protocol which provides convenient and more secure authentication process in some organizational environments. The proposed scheme shows that only those who provide legitimate fingerprint information can be authenticated even in a situation that both password and smart card are compromised.

• Journal of Broadcast Engineering
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• v.12 no.3
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• pp.214-221
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• 2007

In this paper, we presents conformance test tools for the broadcast web site (BWS) service which is one of the data services for terrestrial digital multimedia broadcasting (T-DMB). First, the methodology for the conformance test is established for both transmitters and receivers of T-DMB BWS services. The test tools consist of three parts: BWS bitstream analyzer, BWS reference decoder (software) module, and BWS test bitstreams. For testing transmitted BWS bitstreams, we developed the bitstream analyzer. For testing BWS receivers, we developed the reference Ifecoder module and created the test bitstreams. Actually the bitstream analyzer developed in this paper was used for the verification of the test bitstreams. The same test bitstreams are fed to a BWS decoder module under test and the reference decoder module and the results from the two are compared for verification. The test tools can be used for the test of all the protocol and textual/image specifications related to BWS including MOT protocol, HTML, PNG, MNG, JPEG, and Ecma Script.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.3
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• pp.169-179
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• 2014

For vehicle safety-related services using wireless communications, reliable collection of various driving informations transmitted periodically by neighbor vehicles is the most important. Every host vehicle analyses them to estimate a potential dangerous situation in a very short time and warns drivers to prevent an accident. However tremendous amount of periodic messages can cause the wireless communication in chaos and the services not in safe. In this paper, we propose a time-division broadcasting protocol to mitigate the communication congestion. It utilizes the received information of vehicle velocity and location, i.e. vehicle traffic density on a road to adjust the number of time slots in a given broadcasting period, and transmission power. The simulation results show that message reception ratio is changed to approximately 40% and channel access time also decreased from 10ms to 0.23ms.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.649-652
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• 2009

Now Broadcasting system of TV has been developed from analogue to digital we call that IPTV(Internet Protocol Television) or DCATV(Digital Cable Television). But, The characteristics of digital broadcasting is the high-quality contents of easily and almost no damage piracy, and Copyright loss is increasing by Internet, P2P(Peer to Peer) and personal path. Nevertheless user's permissions that recorded and reuse of broadcasting can't restraint, And Training Materials etc. use of fair program needs to be separated from illegality. In this paper using a digital certificate permit the use of stored program to authorized user and user of fair purpose, And illegal distribution of restriction design and implement a distribution system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.3
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• pp.59-64
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• 2023

Fire and disaster broadcasting systems are divided into analog, digital, and network-based digital public address systems, and important specifications in network-based digital public address systems are low-latency audio, high sampling rate, and multi-channel input and output. In the past, it has been widely used to the AoE method for distinguishing based on the MAC address of the data link layer. However, this method has a problem of increasing complexity and cost. This proposal is an AoIP/UDP method, which allows communication to be easily distinguished by IP address without the need for a separate redundant network, so that the network can be freely used and configured, and cost can be reduced by reducing complexity. After implementing the AoIP/UDP method, the experimental results showed that the cost was improved with the equivalent performance with 2.66ms latency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.4B
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• pp.391-398
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• 2011

In this paper, we propose a MAC protocol for visible light wireless LAN using LED light. The proposed MAC protocol has a function of automatic direction optimization for LED transceiver. There is periodical time slot for broadcasting and registration in the proposed MAC protocol. We used polling method for data transfer in the protocol since visible light is hard to detect carrier and collision by other mobile stations; thus we cannot use CSMA/CD method in visible light LAN. We also amended the MAC frame of IEEE 802.11 to propose a revised version for visible light wireless LAN using LED light. We investigate the performance of the proposed MAC protocol. When the bit rate of physical layer is 100 Mb/s, the net data throughput using the proposed MAC protocol is estimated to 94.386 Mb/s.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.4
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• pp.312-333
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• 2005

SIP(Session Initiation Protocol) has been proposed for session control protocol of Internet multimedia communication system like VoIP(Voice over IP). SIP has complicated session control steps to support various kinds of audio and video formats and to assure service quality of real time data communication. Up until now, existing protocol analyzers can not provide such detailed information of SIP based communication system. In this paper, therefore, we propose a new protocol analyzer as a tool that can analyze and diagnose SIP based multimedia communication system throughout the session initiation, data exchange and session change steps. The propose traffic analyzer, which is called STAT(SIP based Traffic Analysis Tool), Is implemented on Winder's environment so that it is generally usable and extensible. Since STAT analyze low level packets captured via Ethernet broadcasting property, it is able to provide session status and real time traffic monitoring information without any affection to the communication system. The STAT which is implemented in this paper. therefore, is expected to be a useful tool for developing and managing of a SIP based multimedia communication system.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.141-150
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• 2013

Simulation is an important technique to test and verify routing protocol correctness. However, simulation does not guarantee that the protocol works expectedly on a real world environment because it needs to rely on assumptions and simplified properties such as radio characteristics and effects of geographical constraints that may not reflect the real world networking environments. Therefore, a real world experiments are necessary to gain a practical insight into the actual performance of ad hoc networks. In this paper, we build a test-bed to evaluate multi-hop ad hoc networks for high speed video streaming inside a building using AODV-UU routing protocol. Our observation indicates that the considered ad hoc network can provide a sufficient performance for a low rate streaming data in terms of throughput, PDR (Packet delivery ratio) and the average delay.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.1
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• pp.95-101
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• 2009

Wireless Sensor Network (WSN) has limited power and bandwidth. In order to high data rate and high speed communication systems are required. Cooperative communication system can help to decrease power consumption through spatial diversity. In cooperative transmission, one partner node assists one sensor node to transmit their data to destination. Instead of using M partners for M sensor nodes, we propose 1 partner for M sensor nodes. And we proposed relay selection scheme base on ARQ. Proposed protocol offers higher diversity order as conventional one with much less bandwidth and power. The destination will consider the one packets received from the best relay to reduce the complexity of the system. We verified BER performance for the proposed protocol through Monte-Carlo simulation over Rayleigh fading plus AWGN.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.6
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• pp.201-210
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• 2009

Studies on human-centered services are approaching their highest peak with the emergence of a new concept of the network environment, a ubiquitous environment. Among these ubiquitous service technologies, services related to health care are very closely related to the current social environment. In this paper, With social aging and changes in ubiquitous IT environment, studies on health care, which is among the essential application services and which has been defined as a key application technology, and studies related to it have been conducted. In addition, healthcare services, which are essentially applicable to the ubiquitous environment, were suggested by analyzing existing healthcare studies and drawing from them the requirements for such. This paper proposes management protocol for serious case except from health care research. This system is constructed database using RFID, it has location information. It provides procedures to consistently monitor the status of patients and process the outcome in real-time.