• Journal of KIISE:Computing Practices and Letters
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• v.5 no.4
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• pp.498-506
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• 1999

본 논문에서는 ATM 통신프로토콜을 위한 자동시험시스템인 ACTS(ATM Conformance Test System)의 개발과 적용을 소개한다. ACTS는 ITU-T 또는 ATM Forum의 ATM 사용자-망 접속표준을 준용하는 ATM 단말과 망장비의 프로토콜적합성을 확인하는데 사용된다. 본 논문에서는 ACTS 개발에 사용된 방법을 소개한 뒤, ACTS를 실제 ATM 단말과 장비에 적용한 사례들을 소개한다. ACTS의 적용을 통하여 시험대상 장비들이 지닌 프로토콜구현상의 문제점을 파악하였고, 문제에 대한 원인분석을 수행하였다. 또한 이러한 문제점들이 상호운용에 미치는 장애를 예측함으로써, ACTS를 상호운용하는 ATM 장비를 확보하기 위한 유용한 도구로 사용할 수 있음을 보인다.Abstract This paper presents development and application of ACTS(ATM Conformance Test System), an automated test system for ATM protocols. ACTS is a test system that checks conformance of ATM terminal and network equipment implementing either ITU-T or ATM Forum user-network interface. This paper, after presenting the methodology and process used for developing ACTS, conducts case studies of its applications to real ATM equipment. By applying ACTS, we were able to detect numerous problems in protocol implementations of ATM equipment and analyse causes of the problems, thereby demonstrating the efficacy of ACTS as an efficient automated testing tool. Furthermore, by predicting the potential effects of the problems on interoperability, we show how ACTS can be used as a useful tool for ensuring interoperable ATM equipment.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.3
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• pp.284-294
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• 2008

In this paper, we describe an implementation of small mobile robot that can be used at research and application of mobile sensor networking. This robot that will constitute the sensor network, as a platform of multi-robot system for each to be used as sensor node, has to satisfy restrictions in many aspects in order to perform sensing, communication protocol, and application algorithms. First, the platform must be designed with a robust structure and low power consumption since its maintenance after deployment is difficult. Second, it must have flexibility and modularity to be used effectively in any structure so that it can be used in various applications. Third, it must support the technique of wireless network for ubiquitous computing environment. At last, to let many nodes be scattered, it must be cost-effective and small. Considering the above restrictions of the mobile platform for sensor network, we designed and implemented robots control the current of actuator by using additional circuit for power efficiency. And we chose MSP430 as MCU, CC2420 as RF transceiver, and etc, that have the strength in the aspect of power. For flexibility and modularity, the platform has expansion ports. The results of experiments are described to show that this robot can act as sensor node by RF communication process with Zigbee standard protocol, execute the navigation process with simple obstacle avoidance and the moving action with RSSI(Received Signal Strength Indicator), operate at low-power, and be made with approx. $100.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.5
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• pp.948-955
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• 2008

Recently, as the dissemination of the Internet and development of computer network technology, Research is actively underway for realization of the next-generation computing paradigm called Ubiquitous Computing. For realization of Ubiquitous computing, The data recognized from each sensors must be collected on real-time and transferred to applied service so that they may be used as data for providing service to users. However, there are several problem for realization. First, there is no standardization of sensor metadata, interface and event definition. Second, applied service has weak point that difficult of approaching to the data. Third, none interoperability with each platform and protocol. In this paper, we designed Sensor Service Description Language based on XML to resolve problem above. This Language expresses the measurement of the sensor and Service Metadata in the form to be standardized. In addition, we have proposed and development a reference model for USN application service.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.2
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• pp.255-266
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• 2022

Messenger applications applied end-to-end encryption on their own to prevent message exposure to servers. Standardization of a group messaging protocol called Message Layer Security (MLS) with end-to-end encryption is being discussed for secure and efficient message communication. This paper performs safety checks based on the operation process and security requirements of MLS. Confidentiality to a middleman server, which is an essential security requirement in messenger communication, can be easily violated by a server administrator. We define a server administrator who is curious about the group's communication content as a curious admin and present an attack in which the admin obtains a group key from MLS. Reminds messenger application users that the server can view your communication content at any time. We discuss ways to authenticate between users without going through the server to prevent curious admin attacks.

• The Journal of Society for e-Business Studies
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• v.13 no.1
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• pp.21-32
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• 2008

RFID systems provide technologies of automatic object identification through wireless communications in invisible ranges and adaptability against various circumstances. These advantages make RFID systems to be applied in various fields of industries and individual life. However, it is difficult to use tags with distinction as tags are increasingly used in life because a tag usually stores only one object identifier in common RFID applications. In addition, RFID systems often make serious violation of privacy caused by various attacks because of their weakness of radio frequency communication. Therefore, information sharing methods among applications are necessary for expansive development of RFID systems. In this paper, we propose efficient RFID scheme. At first, we design a new RFID tag structure which supports many object identifiers of different applications in a tag and allows those applications to access them simultaneously. Secondly, we propose an authentication protocol to support the proposed tag structure. The proposed protocol is designed by considering of robustness against various attacks in low cost RFID systems. Especially, the proposed protocol is focused on efficiency of authentication procedure by considering security levels of applications. In the proposed protocol, each application goes through one of different authentication procedures according to their security levels. Finally, we prove efficiency of th proposed scheme compared with the other schemes through experiments and evaluation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.284-287
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• 2000

Recently, developing medical devices have a tendency becoming the module for satisfying user's mutual complex needs. Because the most effective method for the observation of patients condition a diagnosis and a treatment is collecting data from various devices and controling operation following it. Module tendency is more popular due to manage easily totally many individual systems. This study implemented communication protocol to control by one control system connecting modular medical devices. Implemented system consist of one master module controlling all module and managing communication and many Slave modules. Communication between each modules introduced SPI(Serial Peripheral Interface) among many synchronous serial communication methods for the exact transmission and receipt of data. All communication executes by packet format. This can detect error. And, this protocol introduced PNP(Plug And Play) function that auto-detect connecting or removing module during running. This protocol exactly transmitted and received in faster speed more than 1Mbps. And in practical application to the ventilator this confirmed to give and take real-time data. And various functions by th central control system is implemented in this protocol.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.221-227
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• 2013

RFID is an automatic identification technology that can control a range of information via IC chips and radio communication. Also known as electronic tags, smart tags or electronic labels, RFID technology enables embedding the overall process from production to sales in an ultra-small IC chip and tracking down such information using radio frequencies. Currently, RFID-based application and development is in progress in such fields as health care, national defense, logistics and security. RFID structure consists of a reader that reads tag information, a tag that provides information and the database that manages data. Yet, the wireless section between the reader and the tag is vulnerable to security issues. To sort out the vulnerability, studies on security protocols have been conducted actively. However, due to difficulties in implementation, most suggestions are concerned with theorem proving, which is prone to vulnerability found by other investigators later on, ending up in many troubles with applicability in practice. To experimentally test the security of the protocol proposed here, the formal verification tool, CasperFDR was used. To sum up, the proposed protocol was found to be secure against diverse attacks. That is, the proposed protocol meets the safety standard against new types of attacks and ensures security when applied to real tags in the future.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.21-28
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• 2015

Currently there are wide variety of web services and applications available for users. Such services restrict access to only authorized users, and therefore its users often need to go through the inconvenience of getting an authentication from each service every time. To resolve of such inconvenience, a third party application with OAuth(Open Authorization) protocol that can provide restricted access to different web services has appeared. OAuth protocol provides applicable and flexible services to its users, but is exposed to reply attack, phishing attack, impersonation attack. Therefore we propose method that after authentication Access Token can be issued by using the E-mail authentication. In proposed method, regular user authentication success rate is high when value is 5 minutes. However, in the case of the attacker, the probability which can be gotten certificated is not more than the user contrast 0.3% within 5 minutes.

• Journal of KIISE:Information Networking
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• v.30 no.1
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• pp.75-81
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• 2003

User authentication, including confidentiality, integrity over untrusted networks, is an important part of security for systems that allow remote access. Using human-memorable Password for remote user authentication is not easy due to the low entropy of the password, which constrained by the memory of the user. This paper presents a new password authentication and key agreement protocol suitable for authenticating users and exchanging keys over an insecure channel. The new protocol resists the dictionary attack and offers perfect forward secrecy, which means that revealing the password to an attacher does not help him obtain the session keys of past sessions against future compromises. Additionally user passwords are stored in a form that is not plaintext-equivalent to the password itself, so an attacker who captures the password database cannot use it directly to compromise security and gain immediate access to the server. It does not have to resort to a PKI or trusted third party such as a key server or arbitrator So no keys and certificates stored on the users computer. Further desirable properties are to minimize setup time by keeping the number of flows and the computation time. This is very useful in application which secure password authentication is required such as home banking through web, SSL, SET, IPSEC, telnet, ftp, and user mobile situation.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.289-294
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• 2014

Recently, the various web service and applications are provided to the user. As to these service, because of providing the service to the authenticated user, the user undergoes the inconvenience of performing the authentication with the service especially every time. The OAuth(Open Authorization) protocol which acquires the access privilege in which 3rd Party application is limited on the web service in order to resolve this inconvenience appeared. This OAuth protocol provides the service which is convenient and flexible to the user but has the security vulnerability about the authorization acquisition. Therefore, we propose the method that analyze the security vulnerability which it can be generated in the OAuth 2.0 protocol and secure user authority authentication method.