• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04a
• /
• pp.811-813
• /
• 2004

IPv6는 IPv4 기반의 인터넷의 주소고갈과 새로운 부가 기능 등의 필요성 때문에 IETF에서 IPv4를 대체하기 위해 채택 된 프로토콜이다. 하지만 IPv4를 어느 한순간에 IPv6로 대체하는 것은 불가능하기 때문에 기존 IPv4와의 호환 및 연동을 위한 여러 메커니즘이 연구되었다. 그 중 NAT-PT(Network Address Translation-Protocol Translation)는 IPv4/IPv6 헤더 변환기술을 적용한 대표적인 변환 메커니즘이며, IP 패킷을 통과하는 망의 IP버전에 맞게 변환 시켜서 전송하는 방식이다. 그러나 모든 패킷들이 하나의 NAT-PT 노드로 집중되므로 병목현상이 발생하며, 이로 인해 성능저하가 발생한다. 본 논문은 NAT-PT 병목현상을 줄이기 위한 방안으로 DNS-ALG 기반된 서버를 이용하여 다중 NAT-PT를 사용한 방법을 제안한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2001.10c
• /
• pp.535-537
• /
• 2001

IPv6 초기 도입단계에서는 IPv4와 IPv6 (Internet protocol version 6)의 혼용이 예상됨에 따라 초기 IPv6 네트워크는 기존 IPv4와의 연동 및 호환을 위해 트랜지션 (transition) 메커니즘과 상호공존 (coexistence mechanism) 메커니즘을 필요로 한다. 이를 위해 다양한 트랜지션 메커니즘들이 제안되고 있는데 크게 터널링 (tunneling)과 변환 (translation) 방식으로 구분할 수 있다. 본 논문은 이러한 메커니즘 중에서 터널링을 이용한 DSTM (dual stack transition mechanism)을 분석한 후 제안된 DSTM의 각 연결별 임시 IPv4 주소할당에 대한 비합리적인 문제점을 개선한 모델을 제시하였다. 본 논문예서 제안한 모델은 기존의 NAT (network address translation) 방식과 유사하게 단일 IPv4 주소와 포트 넘버를 이용하여 각 연결을 식별할 수 있도록 한다. 그리고 DSTM 시스템 구현을 위한 효율적인 알고리즘 설계를 통해 IPv4 패킷을 IPv6 패킷으로 캡슐화 (encapsulation)하여 전송할 수 있는 인터페이스를 구현하여 결과를 분석하였다.

• Proceedings of the IEEK Conference
• /
• 2002.06b
• /
• pp.353-356
• /
• 2002

Due to the increased complexity and size of digital system and the need of the H/W-S/W co-design, C/C++ based system design methodology gains more Interests than ever in EDA field. This paper suggests the methodology in which handshake module corresponding to each basic statement of C is provided of the form of STG(Signal Transition Graph) and then, C statements is synthesized into asynchronous circuit through syntax-oriented translation. The 4-phase handshaking protocol is used for the communications between modules, and the modules are synthesized by the Petrify which is asynchronous logic synthesis CAD tool.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.3B
• /
• pp.217-223
• /
• 2003

In spite of widely deploying information broadcasting services based on Internet, there are some limitations to use them due to the bound of Internet protocol. In this paper, a new Internet broadcasting technology for access network is proposed by employing IP address translation function in base station. There are some advantages such as; no need to allocate IP address to receiver, no need to know web site address, and reduction of traffic for server and network. Especially, this technology is very proper to wireless Internet local information broadcasting.

• Journal of the Korea Society of Computer and Information
• /
• v.6 no.2
• /
• pp.116-122
• /
• 2001

A conventional multicast secure protocol. MVMRP, CBT is designed for a large scaled r protocol so the PIM-SM (protect Independent Multicst-Sparse Mode) routing protocol which small number of clients, long distance path among the hosts and shortest path routing chara weak point of require it's own Core tree and re-keying when the traffic is pass through the ro In this study, proposes a architect for a licit information secure of join/leave to all the user or on-service user. With proposed architect, subgroups for multicast secure group mana will be divided by RP (Rendezvous-Point) unit and each RP has a subgroup manager. As a result, the transmitting time is shortened because there is no need to data translation by group key on data sending and the whole architecture size is samller than the other multicast secure architecture.

• Journal of KIISE:Computing Practices and Letters
• /
• v.6 no.1
• /
• pp.58-67
• /
• 2000

Todays enterprise networks are composed of multiple types of interconnected networks.Enterprise Networks interoperability between these technologies is needed. To enable interworking, it is necessary to be able to map between the relevant object models and to build on this to provide a mechanism to handle protocol conversion on the domain boundaries.In this paper, we describe a gateway between management application in the CORBA domain and agent in the SNMP domain and various integration methods. The main function of the gateway is to dynamically convert the method invocations on object reference in CORBA domain to SNMP messages for MIB entries at remote agents, We also present translation methods from SNMP MIB to CORBA IDL using Direct translation and Abstract translation. JIDM algorithm has no notion of containment and inheritance relationships between object classes and is difficult to understanding between management attribute and SNMP Action attribute. Abstract translation over come these problems.New superclasses define for common attributes and define explicit CORBA method for SNMP Action.It is a methodology for obtaining the CORBA-compliant management agents from already existing SNMP agents.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 1991.10a
• /
• pp.196-198
• /
• 1991

분산 시스팀 환경하에서 여러 다양한 구성요소사이의 상호작용과 통신을 관장하는 규칙들인 프로토콜을 설계하는데 있어서 컴퓨터 과학 및 공학 영역의 형식방법과 소프트웨어 공학기법이 적용되고 있다. 그 결과로서 새로운 영역인 프로토콜 공학(Protocol Engineering)의 중요성이 점차 대두되고 있다. 본 연구에서는 프로토콜 공학 사이클(프로토콜과 서비스 명세, 프로토콜 검정과 검증, 프로토콜 종합, 프로토콜 변환, 성능 평가, 자동 구현, 그리고 적합성 시험) 중에서 적합성시섬 즉, 적합성 시험언어인 TTCN(Tree and Tabular Combined Notation) 특성, 시험시나리오, 그리고 추상적 시험 시나리오를 수행하는 시험언어 번역기(TTCN2C)에 관해서 논하였다.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1545-1549
• /
• 2005

According as computer is supplied in a lot of homes and offices and Internet use increases, various service based on the Internet. Including wireless PDA in the future, many devices such as Internet telephone, TV, refrigerator and oven will be connected on the Internet and Internet address exhaustion will be raised to serious problem gradually. Today, the IPv4 address exhaustion problem has been solved partially using NAT (Network Address Translation) however, the transition to next Generation Internet will be accelerated because of advantages such as mobility, security service, QoS, and abundant IP addresses. In IPv6, all hosts are designed to create and set their address automatically without manager's intervention using Neighbor Discovery Protocol. But, when an IPv6 host sets its address automatically, there are serious security vulnerabilities. In this paper, we analysis security vulnerabilities in auto-configuration and provide security requirements for secure auto-configuration.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.10
• /
• pp.2740-2751
• /
• 1999

Critical to more widespread use of Internet telephony are the smooth interoperability with the existing telephone network and the improved quality of voice connections. Of these requirements, this interoperability comes through the use of Internet Telephony Gateway's which perform protocol translation between an IP network and the Public Switched Telephone Network. In this paper, we have focused on the necessity and possibility of interoperability, and furthermore derives the necessary requirements for interoperability between IP networks and PSTN. For this purpose, we have analyzed the signaling protocols for gateway system. Then, we have modelled the inter-working part using the Petri-Net model. Through reachability trees of the Petri-Net model, we have confirmed that interoperability is possible, and that characteristics of deadlock, liveness, and boundness are satisfied.

• Journal of Korea Multimedia Society
• /
• v.1 no.1
• /
• pp.109-119
• /
• 1998

This paper describes a research result on automatic generation of Abstract Test Suite from INAP protocol in formal specifications by applying many existing related algorithms such as Rural Chinese Postman Tour and UIO sequence concepts. We use the I/O FSM generated from SDL specifications and a characterizing sequence concepts. We use the I/O FSM generated from SDL specifications and a characterizing sequence, called UIO sequence, is defined for the I/O FSM. The UIO sequence is combined with the concept of Rural Chinese Postman tour to obtain an optimal test sequence. It also proposes an estimation methodology of the fault courage for the Test Suite obtained by our method and their translation into the standardized test notation TTCN.