• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.5A
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• pp.889-901
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• 2001

본 논문에서 Multiprotocol Label Switching 시스템을 위한 Label Distribution Protocol의 개발과 분석에 관해서 기술한다. 먼저 Gigabit Switched Router를 만들기 위해서, 상용화시 Carrier Class 제품에 적용하기 위한 LDP의 구현시 고려해야 될 사항에 대해 살피고, 상세 설계를 제안한다. IETF 표준에 의거한 LDP의 구현을 위한 상세 설계는 프로토콜 상태기계의 유도 트리와 프로세스 대수를 사용한 형식적 명세를 사용하여 제시한다. 본 논문에서는 제시된 유도트리와 프로세스 대수를 사용한 프로토콜 동작의 분석을 통해, 구현된 LDP의 상호 연동성과 완전성, 생존성, 도달성, 안전성을 검증한다. 또한 이를 사용하여 구현된 LDP가 기존 상용 제품들과의 연동성과 그 동작의 신뢰성을 확보할 것을 기대한다. 결과적으로 구현된 LDP의 프로토콜 동작들의 검증을 제공한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12B
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• pp.2249-2261
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• 1999

In this paper, we describe the design and implementation of the Label Distribution Protocol (LDP) for Multiprotocol Label Switching System. We review the implementation issues of LDP that is required to make a gigabit switched router, and propose a detail design of it. We present the data structures and procedures for the LDP as a result, which are based on IETF standard. We present design issues for applying this to carrier class products. The implemented protocol could afford 40,000 entries of the IP routing table that is required for deploying this system to commercialized data network. Furthermore this system implemented using the standard API of Unix, as a result, it has portability. By implementing LDP based on the international standard and these implementation issues, we expect that the implemented LDP will be interoperable with other commercialized products. We prove the validity of the design of the LDP through prototyping, and also verify the prototype with the specification using the process algebra and the performance analysis.

• Journal of KIISE:Information Networking
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• v.30 no.2
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• pp.270-281
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• 2003

ETF made the RFCs of MPLS technologies for providing the QoS of ATM or Frame Relay and the flexibility&scalability of IP on the Internet services. IETF has been expanding MPLS technologies as a common control component for supporting the various switching technologies called GMPLS. Also, IETF has standardized the signaling protocols based on such technologies, such as LDP, CR-LDP and RSVP-TE. ETRI developed the MPLS system based on ATM switch in order to provide more reliable services, differentiated services and value-added services like the VPN and traffic engineering service on the Korea Public Sector network. We are planning on deploying model services and commercial services on that network. This paper explains the basic functions of LDP, design and development of LDP on our system, and compares with LDP development and operation on other MPLS systems made by Cisco, Juniper, Nortel and Riverstone. In conclusion, this paper deduces the future services and applications by LDP through these explanation and comparison.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04a
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• pp.436-438
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• 2004

인터넷 서비스에 QoS(Quality of Service)를 제공하면서 IP(Internet Protocol)의 유연성과 확장성을 제공하기 위해 IETF에서는 MPLS(Multiple Protocol Label Switching)기술을 표준화하였다. 또한, MPLS기술의 기본이 되는 시그널링 프로토콜로 LDP(Label Distribution Protocol), CR-LDP(Constrained based LDP). RSVP-TE(Resource Reservation Protocol-Traffic Engineering)의 표준화를 진행해 왔다. 따라서 본 논문에서는 MPLS 기술을 적용하여 현재의 IP망에서 보다 안정적이고 차별화된 서비스를 제공하기 위해 리눅스 상에서 구연한 라우터기반 MPLS 시스템을 제시한다. 본 논문에서 제시하는 라우터 기반 MPLS 시스템은 기존 IP망과의 연동을 위해 MPLS 도메인상의 OSPF데몬을 수정하며, MPLS망에서 명시적 경로를 제어하기 위해 MPLS데몬을 수정한다. 그리고 MPLS데몬과 OSPF데몬은 수정된 Zebra데몬에 의해 스트림 형태로 정보를 교환한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.10 s.340
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• pp.9-16
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• 2005

The growth of the Internet over the last several years has placed a tremendous strain on the high bandwidth Hence, the amount of internet traffic has risen sharply and it has demanded to use the limited resource. MPLS (Multiprotocol Label Switching) is regarded as a core technology for migrating to the next generation Internet. It is important to reduce the number of labels and LSP(Label Switched Path)s for network resource management. In this thesis, we considered an MPLS multicast mechanism in the current Internet. The scalability problem due to lack of labels and multicast property is one of the serious problems in MPLS multicast mechanism, we proposed a Label Aggregation algorithm that the multicast packets on same link in MPLS allocates the same label for the scalability problem. In order to support the proposed algorithm we defined a new LDP(Label Distribution Protocol) multicast field and multicast packet is copied and transmitted for multicast group links of next node in LSR(label Switch Router).

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.686-691
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• 2000

최근 들어 인터넷의 사용이 급격히 증가함에 따라 인터넷의 백본망에는 패킷 전달의 고속성, 확장성 뿐만 아니라 QOS 보장을 요구하게 되었다. 효과적인 인터넷 백본망을 구현하기 위해 본 논문에서는 Multi-Protocol Label Switching(MPLS)를 고려하고 MPLS 에서 인터넷 Quality Of Service(QOS) 서비스 모델 중 백본망에 적합한 Differentiated Service(DS) 모델을 그대로 제공하기 위해 MPLS 와 DS 의 연동에 대한 문제를 다룬다. 우선 MPLS 에서 QOS 제공을 위한 기능요소를 정성적으로 분석한다. 그리고 두 DS 망 가운데 ATM 기반의 MPLS 망을 두고 있는 경우를 가정하여, 종단대 종단간 DS 제공을 위하여 DS 망과 MPLS 망에서의 시그널링 과정을 제안한다. 즉, DS 의 BB 로부터 SLA 를 위한 신호를 MPLS 의 입구 라우터에서 해석하여 DS Type-Length-Value(TLV)를 만들고 이를 이용하여 Constraint-based Label Distribution Protocol(CR-LDP) 시그널링을 통해 마다 Label-Only-Inferred-PSC LSP(L-LSP)를 설립하여 MPLS 에서 DS QOS 를 그대로 제공한다. 또한 입구 DS BB 로부터의 정보를 MPLS 망을 통해 BB 에게 보낸다.

• Journal of KIISE:Information Networking
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• v.27 no.2
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• pp.219-225
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• 2000

In order to provide a proper mobile internet service, Mobile IP is necessary to support IP mobility. Service network should be a backbone network among mobile agents which support mobility, and MPLS(Multi-protocol Label Switching) of IETF(Internet Engineering Task Force) is being considered as a backbone network because of its speed, scalability and the excellent service capability. MPLS, however, doesn't provide a way to support the mobility of the nodes. In this paper, we present an efficient IMT-2000 network architecture using MPLS to handle Mobile IP. The proposed architecture combines the MPLS label distribution and Mobile IP registration. It doesn't use the layer 3 encapsulation, instead it uses layer 2 for tunneling the data, reduces the size of the header, and it can tunnel the data without delay, which is needed to look up the mobility binding list, as a result.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9B
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• pp.834-844
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• 2003

Mobile IP has some performance degrade factors such as triangle routing and packet loss by the hand-off because the original IP was designed for the fixed network. The design goal for the next generation Internet service is to guarantee QoS. So, Mobile IP also should be able to provide the guaranteed QoS with performance enhancement because it is an IP-based mobile Internet service. In this paper, we propose route optimization, smooth hand-off scheme and MIP-LDP(Mobile IP-Label Distribution Protocol) on Mobile IP-over-MPLS framework to enhance the performance of the previously researched Mobile IP-over-MPLS schemes. The proposed framework enhanced long routing path problem and packet loss problem by the hand-off.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.893-902
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• 2002

MPLS enables efficient explicit routing, and thus provides great advantages in supporting traffic engineering. Exploiting this capability, we Propose a load balancing scheme which deploys a multipath routing. It is named LBM (Load Balancing in MPLS networks), and targets at efficient network utilization as well as performance enhancement. LBM establishes multiple LSP (Label Switched Path)s between a pair of ingress-egress routers, and distributes traffic over these LSPs at the new level. Its routing decision is based on both the length and the utilization of the paths. In order to enhance the efficiency of a link usage, a link is limited to be used by shorter paths as its utilization becomes higher Longer paths are considered to be candidate alternative paths as the utilization of shorter paths becomes higher. Simulation experiments are performed in order to compare the performance of LBM to that of static shortest path only scheme as well as the other representative dynamic multipath traffic distribution approaches. The simulation results show that LBM outperforms the compared approaches, and the performance gain is more significant when the traffic distribution among the ingress-egress pairs is non-uniform.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.365-370
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• 2009

LCA is a tool to support for making decisions by offering information of environmental aspects of products or services. It can be used to make decisions to consumers and NGOs as well as government and enterprises. LCA evaluates the environmental aspects throughout the entire life cycle of a product. Therefore it can quantify and assess environmental impacts from raw material acquisition, manufacturing, distribution, use and disposal to end of life and recycling. The demands of the recycling rate increase and the use of suitable materials for RoHS, REACH, WEEE, ELV which are linked trade with environmental regulation have increased the worldwide. Global warming is the critical challenge of the world facing. And under post-Kyoto protocol each country has to prepare for target reduction, so it became essential to save energy and resources. In addition that, the carbon mark has been run as the way of showing example of CO2 reduction in domestic and it will be extended gradually. And also through the introduction of Eco-label, environmentally-friendly product will be promoted. When those systems are operated, global warming gases (i.e. CO2) can be calculated throughout the entire life of the products by LCA. And the environmental impacts such as harmful material emission in the process of manufacturing, energy consumption, distribution and so on, can also be assessed. Therefore, The basic concepts of LCA technique and various cases and the practical application in the future will be review in this study.