• The Transactions of the Korea Information Processing Society
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• v.7 no.8S
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• pp.2774-2782
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• 2000

Release 99 UMTS/GPRS는 Mobile IP 서비스를 제공하기 위한 방안으로서 단계별로 3가지 망 구조를 제안하고 있다. 1단계 망 구조에서 GGSN(Gateway GPRS Support Node)과 FA(Foreign Agent)간 인터페이스는 구현사항으로 기술하고 있으며, GGSN과 FA를 동일 플랫폼에서 구현하는 경우와 별도 플랫폼에서 구현하는 경우를 둘 다 고려하고 있다. 그러나 후자의 경우에 필요한 인터페이스는 표준화 대상에서 제외하고 있다. 따라서 GGSN과 FA를 별도의 플랫폼에서 구현하기 위해서 proprietary한 인터페이스 새로이 정의되어야 한다. 이를 위해 본 논문에서는 GGSN과 FA간 새로운 Gi+ 인터페이스를 정의하고, 이를 실현하기 위해 기본적으로 필요한 데이터 트래픽 프로토콜 구조와 신호 프로토콜 구조를 제안하였다. 그리고 GPRS의 GTP(GPRS Tunneling Protocol)ID를 세션 구별자로 사용하고, Gi+ 세션을 관리하기 위해 GGSN에 단말의 상태 관리 모델을 적용하는 SIAM(Session Identifier Adaptation Mechanism)을 설계 하였다. SIAM의 장점은 GGSN과FA 사이에 Mobile IP 신호 전송은 UDP를, 그리고 데이터 트래픽 전송은 IP-in-IP를 사용할 수 있게 함으로서 Gi+ 인터페이스 구현의 용이성을 제공한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.292-294
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• 2003

이동 단말의 수요가 급속하게 증가하고 무선 인터넷의 보급이 활발해짐에 따라 IP 멀티캐스트를 사용하는 응용 프로그램의 사용 증가가 예상된다. 이를 위해, 유니캐스트와 마찬가지로 이동 단말을 위한 무선 IP 멀티캐스트를 위한 핸드오프 프로토콜이 제시되어야 하는데, 그러한 프로토콜로 원격가입(Remote Subscription)과 양방향 터널링(Bidirectional Tunneling)이 제시되고 있다. 하지만. 이들 프로토콜은 가입 지연시간 발생과 패킷 데이터 중복수신의 문제점을 각각 안고 있다. 이러한 문제점들은 멀티캐스트 단말의 Micro­mobility 지원에 있어서 장애가 된다. 본 논문에서는 계층 구조를 통해 멀티캐스트 트리의 재구성을 최소화하고 원격가입 지연시간을 최소화함으로써 Micro­mobility를 지원하는 프로토콜을 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.76-78
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• 2002

Multicasting over mobile IP network becomes more important with the increasing needs of supporting multimedia services in mobile network. The IETF has suggested two approaches which are remote subscription and bidirectional tunneling for supporting mobility management in multicasting over mobile IP. But these protocols have problems - the frequent reconstruction of multicast delivery tree, packet less during handoff, convergence problem, and so on. In this paper, we propose to use preconfiguration of multicast delivery tree when mobile host enters the foreign network. It will decrease the frequency of multicast delivery tree reconstruction, and reduce the packet loss during handoff, Also the multicast delivery tree maintained by Keep Alive messages makes the signaling overload of networks diminished.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.1
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• pp.120-131
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• 2016

In this paper, a 512b MTP memory IP is designed by using MTP memory cells which are written by the FN (Fowler-Nordheim) tunneling method with only MV (medium voltage) devices of 5V which uses the back-gate bias, that is VNN (negative voltage). The used MTP cell consists of a CG (control gate) capacitor, a TG (tunnel gate) transistor, and a select transistor. To reduce the size of the MTP memory cell, just two PWs (P-wells) are used: one for the TG and the select transistors; and the other for the CG capacitor. In addition, just one DNW (deep N-well) is used for the entire 512b memory cell array. VPP and VNN generators supplying pumping voltages of ${\pm}8V$ which are insensitive to PVT variations since VPP and VNN level detectors are designed by a regulated voltage, V1V (=1V), provided by a BGR voltage generator.

• Journal of Convergence for Information Technology
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• v.9 no.9
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• pp.52-57
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• 2019

DNS stands for 'Domain Name System' and uses IP addresses to identify devices connected to the network on the network. IP is a protocol that registers and manages aliases such as IPs because it is difficult for general users to remember. In recent years, the abuse of such DNS is increasing abroad, and behind the scenes, called 'DNS pionage,' are developing and evolving new rules and malware. DNSpionage attack is abusing DNS system such as Increasing hacking success rate, leading to fake sites, changing or forged data. As a result it is increasing the damage cases. As the global DNS system is expanding to the extent that it is out of control. Therefore, in this research, the countermeasures of DNSpionage attack is proposed to contribute to build a secure and efficient DNS system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.1
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• pp.65-73
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• 2004

In this paper, we propose a tunnel establishment scheme using Next Hop Resolution Protocol over mobile IP networks, which consist of LAN-based IP networks and ATM-based IP networks. As a basic idea, we use the shortest path algorithm to establish a short-cut tunnel between HA and FA. Also, we classify methods for establishing a short-cut tunnel into four cases considering the locations of HA, FA, CN and MN. To confirm the advantages of our schemes, which deliver packets using short-cut tunnel in optimized path method over mobile IP networks, we performed mathematical analysis and simulation, compared proposed schemes with existing IP routing method in terms of transmission delay between CN and MN. The simulation results show that our scheme have superior performance to that of existing IP routing mechanism, because the store-and-forward delay which occurred in IP routing mechanism is considerably reduced in short-cut tunnel over ATM networks.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.163-166
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• 2003

In recent years, there has been increased to access multimedia service through the Internet due to rise of the access speed. We suppose the co-existence of the various access networks in adjacent area in the future, such as wireless LAN, Bluetooth, and 3G Cellular So, the size of the cell will be smaller and the number of access point will be increased. In other words, the potable devices need the efficient mobility scheme due to move between cells frequently Currently, the several of the scheme, which is Cellular IP, HAWAII, Mobile IPv4 regional registration, and hierarchical Mobile IPv6, is suggested to support micro-mobility but Mobile IPv4 is standard scheme to support the mobility of the mobile node. MPLS, which forwards the packet through switching instead of routing using IP address, has begun to deploy in the internet backbone to increase the performance of mobility protocol. The integration of both MPLS and Mobile IP improves the scalability of the Mobile IP data forwarding process by leveraging on the features MPLS which are fast switching and high scalability. Moreover it abbreviates IP-in-IP tunneling between HA and FA. In this paper, we suggest efficient mobility scheme through integration of both MPLS and hierarchical Mobile IPv6.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.7
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• pp.1257-1262
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• 2001

In recent years there has been a lot of interest in carrying IP over WDM networks in an efficient manner. The benefits here include larger bandwidth capacities, better network scalability, and more efficient operation. W based approach, termed "lambda-labeling" is presented for direct If over WDM integration. In this paper, we study on architecture approach method consider of optical Internet evolution that based on MPLamdaS conception of IETF. Label stack conception collect electronic LSP of optical LSP. This paper is proposed method of co-operation between MPLS domain and MPLambdaS domain. Additionally, proposed architecture of Edge Optical LSR.tical LSR.

• Journal of Korea Multimedia Society
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• v.8 no.2
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• pp.258-268
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• 2005

The efficient provision of multicast service to moving hosts in mobile computing environments is not so easy task. Bi-directional tunneling scheme causes overhead about encapsulation and triangular routing. On the other hand, remote subscription scheme need freDuent tree reconstruction, which is inefficient for rapid moving hosts. In this paper we propose Mobility Based Mobile Multicast(MBMOM) scheme which is based on host's mobility information. Ultimately MBMOM try to find the strong points of remote subscription scheme and hi-directional tunneling scheme. If host's mobility speed is considered to be high, multicast packets are forwarded using hi-directional tunneling scheme from home agent continuously. If host's mobility speed is considered to be slow, remote subscription scheme is applied for foreign agent and it try to join multicast tree. We developed analytical models to analyze the performance of proposed scheme and simulated our scheme compared with MOM(Mobile Multicast), RBMOM(Range Based MOM), and TBMOM(Timer Based MOM) schemes. Simulation results show that our scheme has shorter transmission delay than above 3 schemes in the aspect of host's mobility speed and multicast group size.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.620-632
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• 2004

IP is not suitable for mobile nodes by network-based routing because mobile nodes are dynamically change their network attachment point. Mobile-IP is an IETF standard providing continuous access to the Internet for mobile nodes, but it has the triangle routing problem. Also it has a performance degradation problem by massive packet loss during layer 3 handoff of mobile nodes. Especially, two IETF multicast support schemes for Mobile-IP do not guarantee the quality of realtime multimedia services because they have several problems such as long routing path, packet duplication(hi-directional tunneling) and massive packet loss(remote subscription). In this paper, we propose a lossless remote subscription scheme that guarantees the quality of realtime multimedia services over Mobile-IP. From the result of simulation, we verified that the proposed scheme in this paper can reduce the delay time of remote subscription by the effect of the low latency handoff scheme that is extended to apply to the multicast group management and it requires only 0.58% buffer spaces of the previously proposed lossless remote subscription scheme.