• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2843-2852
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• 2013

In the nested mobile network environment, the mobile node selects one of multiple mobile routers. The MR(Mobile Router) by existing top-down or bottom-up methods may not be the optimal MR if the numbers of mobile nodes and routers are substantially increased, and the scale of the network is increased drastically. Since an inappropriate MR decision causes handover or binding renewal to mobile nodes, determining of the optimal MR is important for efficiency. In this paper, we propose an algorithm that decides on the optimal MR using MR QoS(Quality of Service) information, and we describe how to understand the various structured MLP(Multi-Layered Perceptron) based on the algorithm. In conclusion, we prove the ability of the suggested neural network for a nesting mobile network through the performance analysis of each learned MLP.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.38-45
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• 2003

Recently, localized QoS routing scheme was recently proposed for overcome drawbacks of global state QoS routing schemes. Localized QoS routing dose not exchange QoS states among routers, but use virtual capacity based routing scheme instead. In localized QoS routing, to archive good performance, a set of candidate paths must be selected between the source and the destination effectively. In this paper we propose a few heuristics for effective path selection and develop path selection algorithms based on the heuristics. More detail analysis of the proposed algorithm is presented with simulation results which demonstrate that the path selection method can very affect the performance of localized QoS routing.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05b
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• pp.1489-1492
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• 2003

이동 컴퓨팅 환경에서 사용자의 이동 특성은 실시간 멀티미디어 서비스를 제공하기 위해서 요구되는 QoS(Quality of Service)에 심각한 영향을 미친다. RSVP(Resource reservation Protocol)는 유선을 기반으로 실시간 서비스를 제공하기 위해서 제안된 프로토콜로써 이동 환경에 적용하기에는 부적합하다. MRSVP(Mobile RSVP)는 RSVP를 기반으로 사용자의 이동이 QoS에 미치는 영향을 최소화하기 위해서 사용자가 이동할 것으로 예상되는 영역에 대한 자원을 미리 예약하는 프로토콜이다. 본 논문은 기존의 MRSVP를 확장하여 Mobile IP 지역등록(Regional Registration) 프로토콜과 이웃 라우터 발견 메커니즘(Neignbor Router Discovery Mechanism)을 결합하여 동적 앵커 에이전트(DAA: Dynamic Anchor Agent)를 계층적으로 구성하는 QoS지원 방안을 제안한다. 이는 기존의 MRSVP에서 미리 예약되는 자원예약 범위를 네트워치 위상을 고려하여 지역적으로 제한함으로써 자원예약을 최소화하는 반면에 기존의 MRSVP와 유사한 수준의 QoS 보장을 목적으로 한다.

• Journal of the Korea Computer Industry Society
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• v.2 no.9
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• pp.1225-1232
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• 2001

In this paper, we investigate the scheduling algorithm of router system for Internet services on large scale ATM networks based on the quality-of-service(QoS) level of the input source traffics. We suggest an approprite scheduling algorithm in order to satisfy their QoS requirements. For this purpose, we first study the service requirements of the multiplexer in Internet. Second, we suggest functional architecture of the multiplexer for real time services and the scheduling algorithm to satisfy various QoS requirements. Finally, the performance measures of interest, namely steady-state average delay time and fairness of network resources, are discussed by simulation results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6B
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• pp.588-603
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• 2003

In this paper, we propose an Aggregate Three Color Marker without per flow management which is required for an Edge router to improve End-to-End QoS of Assured Service in DiffServ. Proposed Aggregate Three Color Marker is used with the Adaptive RIO-DC scheme to achieve the minimum rate guarantee without per flow management. Assuming that the admission control for Assured Service has been performed, proposed Aggregate Three Color Marker measures incoming In-profile traffic rate at the output link of an edge router using a token-bucket with a token rate equal to the sum of contracted rates of admitted flows passing the edge router. If there are token losses from the token bucket, out-of-profile packets are promoted to Yellow packets within the aggregate traffic profile. And yellow packets are demoted to out-of-profile packets at the input link to an Edge router fer the purpose of fairness maintenance. In-profile packets and Yellow packets are processed identically at the RIO-DC buffer management scheme in our proposed method. Simulation results show that through using proposed Aggregate Three Color Marker with the Adaptive RIO-DC scheme, the minimum rate guarantee for Assured Service can be achieved without per flow management at multiple DiffServ domains.

• Journal of the Korea Society of Computer and Information
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• v.6 no.4
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• pp.154-162
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• 2001

In this paper, we investigate the scheduling algorithm of router system for Internet service based on the qualify-of-service (QoS) level of the input source traffics. We suggest an approprite scheduling algorithm in order to satisfy their QoS requirements for the loss-sensitive traffic and delay-sensitive traffic. For this purpose, we first study the service requirements of the multiplexer in Internet and the definition of QoS based on the ITU-T white recommendations. Second. we suggest a functional architecture of the multiplexer and the scheduling algorithm to satisfy various QoS requirements for Internet service. Finally. the performance measures of interest, namely steady-state packet loss probability and average delay, are discussed by simulation results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4B
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• pp.235-245
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• 2005

In this paper, a simplified QoS model of MPLS-based backbone network. Conventional scheme proposed by IETF(IETF schem) is to embed a DiffServ model in MPLS network. However, this approach results in overall upgrade of MPLS system and so it is difficult to deploy this approach. Our proposed model, however, uses a Vidual Link which is a set of Label Switched Path(LSP) connected from an Ingress Label Edge Router(LER) to an Egress LER. In this model, Per-Hop-Behavior(PHB) is implemented only at each LSP in ingress LER and Core Label Switch Routers(LSRs) just guarantee each LSP's bandwidth, not service. This bandwidth guarantee service is fully provided by legacy MPLS model. Also we propose flow allocation mechanism and the flow distribution among LSPs of the virtual link by the flow according to the network status. To evaluate the simplified approach, the characteristics of the approach are compared logically with these of IETF's one through simulations.

• Journal of Korea Multimedia Society
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• v.11 no.7
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• pp.997-1006
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• 2008

SVP-capable router supporting guaranteed services on the internet generally uses a packet scheduler based on the Weighted Fair Queuing(WFQ) algorithm to secure required qualities of traffic flows. In this paper we proposed a RSVP-capable router based on the LOFQ(Latency optimized fair queuing) algorithm that improves the efficiency in bandwidth utilization with keeping the compatibility with the original RSVP procedure. The proposed router reserves the optimal amount of resource for each flow to secure its required quality-of-service with the recently introduced LOFQ scheduler. The results of the simulation applying the proposed router to an evaluation network showed that it may yield the gain of up to 30% compared to that in the original one in terms of the number of admitted flows.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4B
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• pp.192-201
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• 2005

DiffServ supports aggregated traffic classes to provide various QoS to different classes of traffics. However, current DiffServ specifications do not have a complete QoS management framework. It is possible to lead to serious QoS violations without a QoS management support. From this reasoning, a QoS management system that can manage differentiated QoS provisioning is required. This paper proposes and implements a policy-based QoS management platform for differentiated services networks, which specifies QoS policies to guarantee dynamic QoS requirements. The implementation of the proposed platform is built on W framework and uses XML to represent and validate high-level QoS policies. High-level QoS policies are represented as valid XML documents and are mapped into Em beans of the EJB-based policy server of the platform. The policy distribution and the QoS monitoring are processed using SNMP.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.251-253
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• 2000

VPN이란 공중망에서 물리적인 구성과 무관하게 논리적으로 폐쇄된 사용자 집단을 구성하여 각종 통신 서비스를 제공하는 기술이다. 이러한 VPN을 구성하기 위한 다양한 기술들이 제시되었고, 그 중에서 MPLS를 이용한 방식이 다른 기술에서는 제공하기 어려운 QoS, 보안, 관리 유지 등을 제공하는데 많은 장점을 가지고 있다. 본 논문에서는 기존에 제안된 MPLS를 이용한 Network 기반, 즉 PE 라우터 기반 VPN의 단점을 보안하기 위해 제안된 MPLS를 사용하는 CE 라우터 기반 VPN의 설계 및 구현에 대해 기술하고자 한다.