• Journal of Communications and Networks
• /
• v.10 no.1
• /
• pp.89-97
• /
• 2008

Anomaly detection systems playa significant role in protection mechanism against attacks launched on a network. The greatest challenge in designing systems detecting anomalous exploits is defining what to measure. Effective yet simple, Shannon entropy metrics have been successfully used to detect specific types of malicious traffic in a number of commercially available IDS's. We believe that Renyi entropy measures can also adequately describe the characteristics of a network as a whole as well as detect abnormal traces in the observed traffic. In addition, Renyi entropy metrics might boost sensitivity of the methods when disambiguating certain anomalous patterns. In this paper we describe our efforts to understand how Renyi mutual information can be applied to anomaly detection as an offline computation. An initial analysis has been performed to determine how well fast spreading worms (Slammer, Code Red, and Welchia) can be detected using our technique. We use both synthetic and real data audits to illustrate the potentials of our method and provide a tentative explanation of the results.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.10
• /
• pp.898-907
• /
• 2013

For D2D communications underlaying cellular networks, it is essential to consider the mutual interference between the existing cellular communications and D2D communications as well as the spectral efficiency, as they need to share the same frequency. Accordingly, a resource allocation scheme should be designed in such a way that minimizes the mutual interference and maximizes the spectrum utilization efficiency at the same time. In this paper, we propose a resource allocation scheme based on cooperation of the base station and D2D terminals. Specifically, a D2D terminal senses the cellular spectrum to recognize the interference condition, chooses the best cellular resource, and reports the information to the base station. The base station allocates D2D resource such that the corresponding D2D link and cellular link share the same resource. The performance of the proposed resource allocation scheme is ated through compu under 3GPP LTE-Advanced scenarios.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.3C
• /
• pp.348-354
• /
• 2007

RFID system is emerging new technology for ubiquitous computing environment. RFID system, however, provides privacy problems while the technology offers incredible rich opportunities for applications in the filed of logistics, distribution, and medical services, etc. Many researches have been conducted in order to solve this problem, but the current RFID authentication protocols are still insufficient for settling the privacy problem in the point of view of privacy intrusion and system efficiency. The purpose of this paper is to present a RFID mutual authentication protocol which improves safety level, compared with current authentication protocols. The proposed authentication protocol can provide mutual authentication services, and is secure against location tracing, spoofing, reflection attack.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.6
• /
• pp.540-549
• /
• 2013

An adaptive non-uniform quantization scheme is proposed for soft-decision error correction in NAND flash memory. Even though the conventional maximizing mutual information (MMI) quantizer shows the optimal post-FEC (forward error correction) bit error rate (BER) performance, this quantization scheme demands heavy computational overheads due to the exhaustive search to find the optimal parameter values. The proposed quantization scheme has a simple structure that is constructed by only six parameters, and the optimal values of them are found by maximizing the mutual information between the input and the output symbols. It is demonstrated that the proposed quantization scheme improves the BER performance of soft-decision decoding with only small computational overheads.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.3A
• /
• pp.151-156
• /
• 2003

Millimeter waves are potentially useful for high resolution ranging and imaging in low optical visibility conditions such as fog and smoke. Also, They can be used for wide band communications since the currently used spectrum bands are already crowded. However, it is necessary to develop a theoretical and experimental understanding of millimeter wave propagation to assess the performance of millimeter wave systems. The intensity fluctuations and mutual coherence function (MCF) describe atmospheric effects on the millimeter wave propagation. Using the quasi-optical method (QOM), a practical and efficient method is suggested to obtain MCF from the flux measurement in the antenna focal plane.

• Journal of Internet Computing and Services
• /
• v.5 no.1
• /
• pp.99-111
• /
• 2004

Two general security measures in computing networks are secure data transmission and user authentication, These problems are still critical in the wireless LAN environments. Thus security becomes most significant issue in personal network environments and ubiquitous networks based on wireless LANs. We purpose a new authentication system for these kind of environments, and coined it UPMA(Ubiquitous Personal Mutual Authen-tication) model. UPMA supports authenticating configurations which provides personal verification for each system. It guarantees secure communications through the session key setup, and provides mutual authentication by verifying each user and his/her station. UPMA solves security problems in ubiquitous networks without accessing authentication server, Instead it performs mutual authentication between terminals or between systems. It is a global authentication system which enables global roaming service through the Internet or other public networks, It can be used to guarantee safe and convenient access to a company Intranet or to a home network.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.2
• /
• pp.254-262
• /
• 2016

With the increased demand for automotive radar systems, mutual interference between vehicles has become a crucial issue that must be resolved to ensure better automotive safety. Mutual interference between frequency modulated continuous waveform (FMCW) radar system appears in the form of increased noise levels in the frequency domain and results in a failure to separate the target object from interferers. The traditional fast fourier transform (FFT) algorithm, which is used to estimate the beat frequency, is vulnerable in interference-limited automotive radar environments. In order to overcome this drawback, we propose a high-resolution frequency estimation technique for use in interference environments. To verify the performance of the proposed algorithms, a 77GHz FMCW radar system is considered. The proposed method employs a high-resolution algorithm, specially the multiple signal classification and estimation of signal parameters via rotational invariance techniques, which are able to estimate beat frequency accurately.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.21 no.4
• /
• pp.822-834
• /
• 2007

This study searched the philosophical and medical thought of mutual understanding and human body. Mutual understanding is a fundamental problem in all branches of oriental studies. In other words, mutual understanding becomes the existential foundation of heaven-earth-human(三才). So human beings, heaven and the earth can't exist if there is no mutual understanding. It comes out the problem of self-consciousness in philosophy, and qi movement pattern like upward, downward, inward and outward movement in traditional korean medicine. Human beings have mutual understandings with heaven and the earth from a macroscopic standpoint, on the other side the human body from a microscopic standpoint. Qi movement is the mutual understanding and response of qi in human body, so with which the physiological functions and pathologic changes of viscera and bowels comes out. Therefore we want to present how to complete qi movement between viscera-bowels and organs to examine mutual understandings in human body closely. The results was summarized as follows; First, upbearing the clear yang and down bearing the turbid yin of spleen-stomach is main pivot of upward and downward of qi movement, and it is true form of mutual understandings between viscera and bowels, so upward, downward, inward and outward movement of whole viscera and bowels can be controlled by spleen-stomach. Second, by restraining relationships between downward heart fire and upward kidney water, heart fire and kidney water have close communications physiologically and pathologically as upper-lower, yin-yang and water-fire. Third, by restraining relationships between upbearing and effusion of liver and purification and down-sending of lung, liver and lung are outer circles of upward and downward movement, so they have antagonistic functions. Firth, by the relationships between upbearing the clear and down bearing the turbid of spleen-stomach and free coursing of liver, free coursing of liver-gallbladder is the essential requirement that it certify transportation and transformation of spleen-earth, so the disease of liver-gallbladder induce spleen-stomach disease pattern to affect its function of transportation and transformation. Fifth, by spleen and kidney, spleen yang is based on kidney yang, so the weakness of kidney yang can affect the function of transportation and transformation of spleen-stomach as it can't warm spleen earth. Sixth, by homogeny of liver-kidney, essence and blood of liver-kidney and ministerial fire of liver-kidney have mutal generation and limitation physiologically and they mutually are affected in pathologically.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2003.09a
• /
• pp.256-259
• /
• 2003

This paper presents mutual authentication scheme between user and network on mobile communications using public key scheme based on counter, and simultaneously shows key agreement between user and user using random number for secure communications. This is also a range of possible solutions to authentication and key agreement problem-authentication and key agreement protocol based on nonce and count, and secure end-to-end protocol based on the function Y=f(.)$\^$1/, C$\^$i/ is count of user I, and f(.) is one way function.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.9
• /
• pp.2064-2071
• /
• 2012

The generalization trend of smart phones have brought many smartphone games into daily lives. These games are mainly dependent on the interactions on the display of the phone using finger touches. On the other hand, functions for detecting the positions and actions of the phones such as gyro-sensors have been rapidly developed over the former orientation sensors and acceleration sensors. Though it has become technologically possible to detect the users' motion via the smartphone devices and to use the phone device directly as the game device, it is hard to find the actualized cases. This paper proposes a new paradigm including basic frameworks and algorithm for the games combining the motion recognitions and mutual communications on the smartphones and finally presents the details of its implementation and results.