• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1434-1440
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• 2008

Performance of TCP/IP is studied on the wireless network using flow control and congestion control mechanism based on transmission rate. We discuss the elimination or the reduction of various phenomena of burst by flow controlling on transmission rate and verify that there are TCP ACK compression promblems on the queue by burst reaction while executing transmission rate controlled channels. Analyzing periodic burst reaction on the queue of source IP, the maximum value of queue is expected, which represents the applible expectation of throughput reduce and shows the improvement of performance by the reduce of throughput due to hi-directional traffic.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.305-309
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• 2006

The important field of research on ship operation is related to the high efficiency of transportation, the convenience of maneuvering ships and the safety of navigation. For these purposes, many intelligent technologies for ship automation have been required and studied. As a way of practical application for a smart ship based on network system, this paper proposes the intelligent control system for ship steering gear based on TCP/IP and desires to testify the validity of the proposal by applying the fuzzy control model to the steering gear system. As study method, the fuzzy inference was adopted to build the maneuvering models of steersman and then the network system was implemented using the TCP/IP Socket programming. Lastly, the miniature steering control system was designed to testify for its effectiveness.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.301-306
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• 2006

The important field of research on ship operation is related to the high efficiency of transportation, the convenience of maneuvering ships and the safety of navigation. As a way of practical application for a smart ship based on network system, this paper proposes the intelligent support system for ship steering control system based on TCP/IP and desires to testify the validity of the proposal by applying the fuzzy control model to the steering control system. As the specific study methods, the fuzzy inference was adopted to build the maneuvering models of steersman, and then the network system was implemented using the TCP/IP socket-based programming. Lastly, the miniature model steering control system combined with LIBL (Linguistic Instruction-based Learning) was designed to testify for its effectiveness.

• Journal of Internet Computing and Services
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• v.6 no.1
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• pp.1-12
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• 2005

Recently, the patterns of cyber attack through internet have been various and have become more complicated and thus it is difficult to detect a network intruder effectively and to response the intrusion quickly. Therefore, It is almost not possible to chase the real location of a network intruder and to isolate the Intruder from network in UDP based DoS or DDoS attacks spoofing source IP address and in TCP based detour connection attacks. In this paper, we propose active security architecture on active network to correspond to various cyber attacks promptly. Security management framework is designed using active technology, and security control mechanism to chase and isolate a network intruder is implemented. We also test the operation of the active security mechanism implemented on test_bed according to several attack scenarios and analyze the experiment results.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.73-83
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• 2010

This paper investigates protocol architecture of a Web-ZigBee gateway for interconnecting TCP/IP-based networks and ZigBee/IEEE802.15.4-based wireless sensor networks. The Web-ZigBee gateway delivers data between the TCP/IP network and the ZigBee network. Since those two networks have different communication protocols, a protocol translation mechanism is needed. Herein, we propose a method to deliver query messages from the Internet to the sensor network and receive data from sensors. The protocol translation is performed in the translation layer that is placed above the two application layers, i.e., the Internet application layer and ZigBee application layer. Among various interfaces, we use CGI programming to take care of translation functions efficiently. The CGI manages query information from a client on the Internet and data from the ZigBee sensor network. Whereas the TCP/IP enabled sensor network overlays two heterogeneous communication protocols, overlaying layers increase the complexity and cost of implementing the sensor network. On the contrary, the sensors in our gateway-based system are not only light (because each communication protocol works independently without overlaying), but also efficient because the translation layer mostly alleviates header overloading.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.2
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• pp.131-136
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• 2008

From the reciprocal connection by this Internet network researchs about the efficiency improvement of the whole system is accomplished with the method which reduces delays in message transmission. From here, we will do a comparative study between the user data program protocol (UDP) and the zero copy which does not use the buffer cache to fine out the valid method to improve the efficiency. In this thesis, I will change the message copy from execution process of the buffer cache of the TCP/IP on Unix OS with process on Linux OS. The object of conversion is to show you that the zero copy which doesn't use the buffer cache from transfer control class improves the communication efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.5
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• pp.1013-1027
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• 2011

In this paper we propose ATCS, a practical TCP protocol coding scheme based on network coding for satellite IP networks. The proposal is specially designed to enhance TCP performance over satellite networks. In our scheme, the source introduces a degree of redundancy and transmits a random linear combination of TCP packets. Since the redundant packets are utilized to mask packet loss over satellite links, the degree of redundancy is determined by the link error rates. Through a simple and effective method, ATCS estimates link error rates in real time and then dynamically adjusts the redundant factor. Consequently, ATCS is adaptable to a wide range of link error rates by coding TCP segments with a flexible redundancy factor. Furthermore, the scheme is compatible with traditional TCP variants. Simulation results indicate that the proposal improves TCP performance considerably.

• The Journal of Engineering Research
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• v.5 no.1
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• pp.45-55
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• 2004

NAT (Network Address Translation) is an IP address modification protocol that translates private IP address into authentic Internet address. The main features of NAT are to improve network security and to save IP address. Generally speaking, in order to perform its functionality, NAT uses the address information in the packet header. Certain application protocols, however, use the information in the packet data as well as the information in the packet header to perform end-to-end communication. Therefore, to support these types of application protocols, NAT should be able to perform appropriate translation of protocol information in the packet data. In this thesis, we design and implement a method which translates virtual IP information in the packet date into real IP information by using port proxy server.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.6
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• pp.625-630
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• 2010

With regard to the examples of establishing various sorts of information security, it can be seen that there are gradual, developmental procedures including Firewall and VPN (Virtual Private Network), IDS (Intrusion Detection System), or ESM(Enterprise Security Management). Each of the security solutions and equipments analyzes both defense and attack for information security with the criteria of classifying the problems of security policies by TCP/IP layers or resulted from attack patterns, attack types, or invasion through specialized security technology. The direction of this study is to examine latency time vulnerable to invasion which occurs when L2-stratum or lower grade equipments or policies are applied to the existing network through TCP/IP layer's L3-stratum or higher grade security policies or equipments and analyze security holes which may generate due to the IP preoccupation in the process of establishing policies to limit particular IP area regarding the policies for security equipments to figure out technological problems lying in it.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1415-1419
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• 2008

In this paper, we investigate various Audio Transmission Systems to implement Audio Transmission System based on AoIP of Internet transmission technology TCP/IP Network and we design and implement a Audio transmission system based on AoIP by adopting the most efficient one. The implemented system can be applied for various professional audio systems with large-scale audio distribution network as well as small-scale PA systems. Moreover, this can be applied in various fields which need audio transmission.