• Proceedings of the Korea Information Processing Society Conference
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• 2003.05b
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• pp.1201-1204
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• 2003

현재는 IPv4의 주소 체계를 사용하여 많은 단말기들이 인터넷에 연결되고 있다. 32비트 주소 체계인 IPv4는 앞으로 유비쿼터스 환경에서 모든 단말기에 주소를 할당 할 수 없는 문제점을 가지고 있다. 이런 문제점을 해결하기 위해 새로운 주소 체계인 IPv6가 연구되고 있다. 현재의 주소 체계를 사용하고 있는 대부분의 단말기들과 IPv6의 주소 체계를 사용하는 단말기들을 직접 연결하는 것은 불가능하다. IPv4에서 IPv6의 주소 체계로 넘어가는 과도기적 단계에서 두 프로토콜 간외 상호 변환이 필요하다. 본 논문에서는 IPv4와 IPv6의 변환 기술인 SIIT(Stateless IP/ICMP Translator)를 하드웨어로 설계하기 위하여 VHDL로 모델링 하였으며 FPGA에서 검증하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.701-705
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• 2002

This paper describes implementation of IPv6-IPv4 transition toolbox named as 6TALK(IPv6 TrAansLator of Krv6) and some scenarios using 6TALK which enables IPv6 island to connect other IPv6 island or IPv4 island seamlessly. 6TALK implements some transition mechanisms suggested in NGTrans Working Group of IETF. Those mechanisms are composed of basic mechanism, tunneling, and applied mechanism such as DSTM. 6TALK provides functions which enable IPv6 network at the edge of existing network to communicate with IPv4 network by using these transition mechanisms. As major transition mechanisms in 6TALK we adopt NAT-PT/SIIT and DSTM/DSTM options and as implementation environment we use Linux Kernel 2.4.18 and Netfilter framework. Software modules implemented in Linux kernel was ported to hardware box using Motorola MPC 8260 processor. The transition mechanisms used in 6TALK are the ones predicted to be used in initial transition step to IPv6.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11B
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• pp.736-743
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• 2005

NAT-PT is one of the IPv6 transition mechanisms, as defined in RFC2766, allowing IPv6-only devices to communicate with IPv4-only devices and vice versa. In NAT-PT, sender fail to verify TCP/UDP checksum and authentication data due to IP translation in the NAT-PT server The NAT-PT, therefore, has a limit to applying the IPsec that provides the end-to-end security such as confidentiality, authentication, and integrity. This paper proposes a scheme to apply the IPsec using IP HTI in NAT-PT environment.

• Journal of Magnetics
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• v.18 no.3
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• pp.311-316
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• 2013

Digital image processing has increasingly been implemented in nanostructural analysis and would be an ideal tool to characterize the morphology and position of self-assembled magnetic nanoparticles for high density recording. In this work, magnetic nanoparticles were synthesized by the modified polyol process using $Fe(acac)_3$ and $Pt(acac)_2$ as starting materials. Transmission electron microscope (TEM) images of as-synthesized products were inspected using an image processing procedure. Grayscale images ($800{\times}800$ pixels, 72 dot per inch) were converted to binary images by using Otsu's thresholding. Each particle was then detected by using the closing algorithm with disk structuring elements of 2 pixels, the Canny edge detection, and edge linking algorithm. Their centroid, diameter and area were subsequently evaluated. The degree of polydispersity of magnetic nanoparticles can then be compared using the size distribution from this image processing procedure.