• Journal of Information Technology and Architecture
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• v.10 no.1
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• pp.101-111
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• 2013

Internet traffic volume has been increasing rapidly due to popularization of various smart devices and Internet development. In particular, HTTP-based traffic volume of smart devices is increasing rapidly in addition to desktop traffic volume. The increased mobile traffic can cause serious problems such as network overload, web security, and QoS. In order to solve these problems of the Internet overload and security, it is necessary to accurately detect applications. Traditionally, well-known port based method is utilized in traffic classification. However, this method shows low accuracy since P2P applications exploit a TCP/80 port, which is used for the HTTP protocol; to avoid firewall or IDS. Signature-based method is proposed to solve the lower accuracy problem. This method shows higher analysis rate but it has overhead of signature generation. Also, previous signature-based study only analyzes applications in HTTP protocol-level not application-level. That is, it is difficult to identify application name. Therefore, previous study only performs protocol-level analysis. In this paper, we propose a signature generation method to classify HTTP-based traffics in application-level using the characteristics of typical semi HTTP header. By applying our proposed method to campus network traffic, we validate feasibility of our method.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.247-249
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• 2005

최근 디지털 TV, DVD 플레이어, 홈시어터와 같은 디지털 A/V 기기들을 통합하여 멀티미디어 컨텐츠를 서비스 받는 홈 네트워크 기술에 대한 관심이 높아지고 있다. 이러한 환경에서 UpnP를 이용한 디지털 기기들의 상태를 모니터링하고, 사용자의 요청과 제어 명령을 전달하여, 멀티미디어 컨텐츠를 서비스 받을 수 있도록 하는 연구는 매우 중요하다. 그러나 UPnP는 TCP/IP 기반의 프로토콜을 사용하기 때문에 사용자 인터랙션에 의한 전송 지연 시간이 발생한다. 그러므로 본 논문에서는 셋탑 박스에 최적화된 UPnP AV 시스템을 구현하고 AV 컨텐츠의 효율적인 재생을 위한 UPnP프레임워크의 재생 기법을 제안한다. UPnP AV 시스템은 미디어 서버가 있고, 미디어 서버에 저장된 비디오/오디오 파일 등을 전송받아 재생하기 위한 셋탑 박스에는 컨트롤 포인트와 UPnP 미디어 렌더러의 통합 모델이 탑재된다. 이러한 기법은 다양한 기기를 제어하고 호환성을 제공하는 UPnP프레임워크가 될 수 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.11
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• pp.993-1003
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• 2012

In this paper, we propose a method that wireless mobile nodes can obtain high throughput in heterogeneous wireless networks using multiple connections and it has low packet loses under handover situation. Currently, a mobile node exchanges data with server for one network connection. The proposed method can use high throughput because it doesn't only use one network(WLAN, 3G, etc.) but also use multiple wireless networks. When mobile nodes move to area to use multiple connection, mobile nodes request heterogeneous wireless networks using multiple connections message from the server and the server transmit packets using multiple connections. Also, this method doesn't disconnect previous networks, so packets losses are decreased. Using the NS-2 simulation, we verify that the propose method enhances throughput.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.263-268
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• 2010

This paper shows the key management system in a small metallic cabinet using a small UHF RFID tags. Each key chain with a key has a custom-designed small RFID tag antenna. There are 6 metallic racks in the small cabinet, and each rack can hold 60 key chains. Therefore, the small cabinet can hold 360 key chains with tags. The 360 key chains with RFID tags in a cabinet are recognized by RFID key chain management system. Even though it is hard to recognize 360 tags in the a cabinet, this RFID key management system with small custom designed RFID tags can recognize all the tags in the small cabinet. To read the all the tags, the locations of antennas and tag shapes are optimized. The reading rates based on the bios-version of the reader and the locations of the reader antennas are compared.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3B
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• pp.339-348
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• 2004

Packet classification is an important factor to support various services such as QoS guarantee and VPN for users in Internet. Packet classification is a searching process for best matching rule on rule tables by employing multi-field such as source address, protocol, and port number as well as destination address in If header. In this paper, we propose hardware based packet classification algorithm by employing tree bitmap of multi-bit trio. We divided prefixes of searching fields and rule into multi-bit stride, and perform a rule searching with multi-bit of fixed size. The proposed scheme can reduce the access times taking for rule search by employing indexing key in a fixed size of upper bits of rule prefixes. We also employ a marker prefixes in order to remove backtracking during searching a rule. In this paper, we generate two dimensional random rule set of source address and destination address using routing tables provided by IPMA Project, and compare its memory usages and performance.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.61-67
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• 2018

Emulab software was developed by the team of University of Utah and it has been replicated at dozens of other sites in the world. Although KREONET Emulab, which established by the Korea Institute of Science and Technology Information, has only a modest number of compute nodes it has been provided an ideal playground to conduct various research for network protocols, cyber security and convergence research. A testbed is a critical enabler of experimental research and researchers only carry out the experiments that are supported by the testbed. This paper outlines the Utah Emulab's status and use types among the last 10 years of operation results and compares them with the ones with the KREONET Emulab. In addition, Testbed-as-a-Service(TaaS) is discussed to upgrade the testbed for the convergence research community services.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.3
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• pp.22-30
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• 2001

This paper investigated future telemedicine as implementation of the telemonitoring system using LAN environment. For telemonitoring system rapidly implementation used the PC compatible embedded computing system in the ROMDOS and application program used the WATTCP that free TCP/IP Stack. Host computer program - programed by Visual C++ - had saved ECG signal and Patient Data coming inside Embedded PC and displayed. Embedded PC acquired ECG signal and transmitted a Packet to Host Computer. Host Computer remote access Embedded PC. This structure is the same Client/Sever Model. This system will be basic telemedicine model. There are problems of realtime telemonitoring because of network delay and data packet. Because of these problems, telemedicine systems will be required faster network speed and method of bio-signal transmission.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.192-197
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• 2002

1. 실시간 모니터링 -온실 내부환경의 계측장치로 모듈화된 단일 칩 마이크로프로세서를 이용한 하우스 모니터를 개발하였다. 개발된 다수의 하우스 모니터는 RS-485통신을 이용하여 개발된 프로토콜을 통하여 그룹 모니터와 통신하면서 계측 데이터를 전송하였고 안정된 계측 성능을 보였다. 또한 그룹 모니터는 하우스모니터로부터 수신한 데이터를 인터넷 환경 TCP/IP 통신에 의해 서버에 정보를 전송하고 데이터베이스 서버에 저장할 수 있었다. 2. 클라이언트 서버 모델 -클라이언트 모니터를 통하여 허용된 사용자들은 해당 온실의 상황을 원격지에서 파악할 수 있는 있었다. 또한 분산환경 기술을 이용하여 서버를 경유하여 데이터베이스 서버에서 데이터 셋을 가져와 과거 재배 사례 등을 조회 및 이용 가능하였다. 이는 전문가에게 접근을 허용함으로써 재배에 관한 지원이 가능하도록 하였다. 데이터 베이스 시스템으로 연계하여 온실환경 정보를 분석하는 것이 가능하였다. 3. 기대효과 및 나아가야 할 방향 -개발된 시스템을 식물 공장 내 작물의 재배환경을 데이터베이스화하여 재배사례 데이터베이스를 형성하고 작물이 가장 잘 자라는 최적 재배 환경을 연구하여 고품질의 작물 재배에 이용될 수 있다. 또한 식물공장의 운전실적, 환경 조건, 환경 조절비용 등의 분석에 효율적으로 이용될 수 있을 것으로 예상되며 각 환경인자들과의 관계를 구명하는데 도움을 줄 것이다. 축적된 작물의 재배 사례 데이터베이스를 이용하여 작물 특성 및 재배 연구에 도움을 줄 수 있을 것이다. 제어 장치들의 운영실적을 분석함으로써 제어 시스템의 효율적이고 경제적인 제어가 가능하도록 할 수 있을 것이다. 이들이 모두 완성되면 전문가 및 전문가 시스템으로부터 지원을 받는 지능형 식물공장이 가능할 것이다. 본 연구에서 개발한 계측 모듈 및 데이터베이스 시스템은 실제 농가에 설치된 전용선을 이용하여 실증 실험을 통해 수정·보완하여야 할 것이다. 또한 시설원예분야에서 있어서 통신체계에 대한 표준화 연구가 수행되어 앞으로 개발될 다른 시스템들과의 호환성을 갖도록 해야 할 것이다. 앞으로 온실의 경영 및 관리 데이터베이스를 개발하여 첨단온실의 통합 관리 및 정보 시스템을 구축하여야 할 것이다. 또한, 시설원예의 환경 설계의 기준을 적용할 수 있도록 하여야 할 것이다.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3651-3667
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• 2000

Recently, in the distributed multimedia environments based on internet, as radical growing technologies, the most of researchers focus on both streaming technology and distributed object thchnology, Specially, the studies which are tried to integrate the streaming services on the distributed object technology have been progressing. These technologies are applied to various stream service mamgements and protocols. However, the stream service management mexlels which are being proposed by the existing researches are insufficient for suporting the QoS of stream services. Besides, the existing models have the problems that cannot support the extensibility and the reusability, when the QoS-reiatedfunctions are being developed as a sub-module which is suited on the specific-purpose application services. For solving these problems, in this paper. we suggested a QoS Integrated platform which can extend and reuse using the distributed object technologies, and guarantee the QoS of the stream services. A structure of platform we suggested consists of three components such as User Control Module(UCM), QoS Management Module(QoSM) and Stream Object. Stream Object has Send/Receive operations for transmitting the RTP packets over TCP/IP. User Control ModuleI(UCM) controls Stream Objects via the COREA service objects. QoS Management Modulel(QoSM) has the functions which maintain the QoS of stream service between the UCMs in client and server. As QoS control methexlologies, procedures of resource monitoring, negotiation, and resource adaptation are executed via the interactions among these comiXments mentioned above. For constmcting this QoS integrated platform, we first implemented the modules mentioned above independently, and then, used IDL for defining interfaces among these mexlules so that can support platform independence, interoperability and portability base on COREA. This platform is constructed using OrbixWeb 3.1c following CORBA specification on Solaris 2.5/2.7, Java language, Java, Java Media Framework API 2.0, Mini-SQL1.0.16 and multimedia equipments. As results for verifying this platform functionally, we showed executing results of each module we mentioned above, and a numerical data obtained from QoS control procedures on client and server's GUI, while stream service is executing on our platform.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.7
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• pp.109-117
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• 2010

Building a large-scale testbed for Future Internet is very important to evaluate a new protocol and new network architecture designed by clean-slate approach. In Korea, new Future Internet testbed project, called FIRST (Future Internet Research for Sustainable Testbed), has been started since Mar. 2009 to design and test new protocols. This project is working together with ETRI and 5 universities. The FIRST@PC is to implement a virtualized hardware-accelerated PC-node by extending the functions of NetFPGA card and build a Future Internet testbed on the KOREN and KREONET for evaluating newly designed protocols and interesting applications. In this paper, we first briefly introduce FIRST@PC project and explain a 'MAC in IP Capsulator' user-space program using raw-socket in Linux to interconnect OpenFlow enabled switch sites on the KOREN and KREONET. After that, we address test results for TCP throughput performance for varying packet size. The test results show that the software based capsulator can support a reasonable bandwidth performance for most of applications.