• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.5
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• pp.941-950
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• 2001

In this paper, we present the integrated network architecture for supporting mobile IP in third generation mobile communication networks, and propose the end-to-end QoS control mechanisms of DiffServ and QoS control functions of each network element in the proposed network. First, the QoS supporting schemes of IMT-2000 are described. Second, the necessities of integrating the networks are discussed and the integrated architecture are proposed. Third, the mapping between wireless channels and DiffServ classes are presented. Finally, the end-to-end QoS control mechanisms are proposed. We also analyze the link level protocols with QoS provisioning for mobile multimedia assuming that the system support voice and data traffic simultaneously. In case of data traffic, the delay and throughput of SREJ ARQ and Type-1 Hybrid ARQ scheme are compared, and In case of voice traffic, the packet loss rate of BCH coding is analyzed according to the varying data traffic loads. The results indicate that the adaptive link level protocols are efficient to meet the QoS requirements while the complexities are increased.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.8
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• pp.1958-1969
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• 1996

This paper proposed a new approach to adaptive call admission control based on a neural network for multiple service classes with different quality of service (QoS) in the ATM-based Broadband Integrated Services Digital Networks. the proposed method extend Hiramatsu's neural network based "leaky pattern table" method for the single QoS[1, 2, 3] to deal with multiple services with different QoS by constructing multiple pattern tables based on each service's acceptance or rejection at the call set-up requests, and by simultaneously controlling each service's QoS according to the target QoS of the service and the trunk capacity. Computer simulation results on two service classes with different traffic characteristics and different cell loss rates as QoS, highlight good performance and effectiveness of the proposed call admission controller for multiple service classes.e classes.

• Journal of Digital Convergence
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• v.11 no.5
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• pp.313-318
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• 2013

QoS in wireless multimedia sensor networks is an important issue to enhance streaming media service. This paper proposes a new 2-layer based QoS evaluation scheme for enhancing the streaming media QoS of wireless multimedia sensor networks. The proposed scheme performs the fuzzy relevance to control the streaming between application layer and network layer, and it performs 2-layer mapping process to enhance the transmission reliability and throughput. The simulation results show that the proposed scheme achieves improved performance in packet control ratio, transmission reliability, and delay overhead ratio compared with those of other existing schemes.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.8-15
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• 2003

In this paper, we address how to provide absolute differentiated services for optical burst switching (OBS) networks based on dynamic wavelength assignment. Unlike existing quality of service (QoS), such as buffer-based and offset-time based scheme, our proposed dynamicvirtual lambda partitioning (DVLP) scheme does not mandate any buffer or extra offset time, but can achieve absolute service differentiation between classes. This new DVLP scheme shares wavelength resources based on several different priority of classes in an efficient and QoS guaranteed manner. The performance results show that the proposed scheme effectively guarantees a target blocking probability of each traffic classes both in Poisson and Self-similar traffic environment.

• Journal of Korea Multimedia Society
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• v.8 no.1
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• pp.62-70
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• 2005

In this paper, we present an architecture for supporting QoS multicast routing in mobile ad-hoc networks. The proposed architecture consists of three parts as follows. The first part is a mobility-based clustering as underlying structure for supporting stable multicast services. In the second part, a framework which can support and evaluate the stability of route and network for supporting QoS routing is presented. In the third part, we describe a method which uses two structures of the first and second parts for supporting QoS multicast routing services. The performance evaluation of our proposed architecture is accomplished via modeling and simulation using the Optimized Network Engineering tool(OPNET).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.116-124
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• 2003

According to the convenience and efficiency, IEEE 802.11 WLAN(Wireless LAN) has became rapidly wide-spread on the market. However, QoS support is needed for various multimedia service. In this paper, we consider both MAC method of IEEE 802.11 and IEEE 802.11e and Traffic Category differentiated service by QoS support method. In addition, we study currently existing back-off algorithms in view of comparative analysis. As a result we propose a new back-off algorithm called Collision Rate Based-EDCF. The proposed back-off algorithm confirms the performance by computer simulations in terms of Throughput, and QoS support.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3A
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• pp.244-257
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• 2009

We analysed the opportunistic scheduling method in MMR proposed by Samsung Electronic Cooperation and confirmed the efficiency by simulation. We also investigated the relationship between the throughput and fairness under the proposed method. The main objective of this study is to propose an opportunistic packet scheduling method in MMR, which considers the QoS requirement of user. Using the simulation the performance of the proposed method is compared with those of i) pure opportunistic packet scheduling method which doesn't consider QoS requirement and ii) packet scheduling method which only consider the QoS requirement, but does not utilize opportunistic packet scheduling.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.153-155
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• 2000

MCNS의 DOCSIS 규격은 국내외에서 케이블 TV 망을 이용한 HFC 시스템과 무선 링크를 사용하는 BWLL 시스템에서 공유 매체를 통한 데이터 전송 동작 규격으로 사용되고 있다. 기존의 MCNS MAC 프로토콜은 IP 데이터 전송을 위한 Best Effort 서비스 지원하기 위해 설계되었기 때문에 기존 방식으로는 멀티미디어 서비스들을 지원하는데 많은 어려움이 있었다. 이를 해결하기 위해 MCNS에서는 DOCSIS1.1부터 QoS를 지원하기 위한 동작을 추가하였다. 본 논문에서는 새로 규격에 추가된 QoS 관련 서비스 동작 절차와 상향 채널 할달 스케쥴링 방식에 대해 설명하고, 규격에서 정의된 스케쥴링 서비스를 기반으로 각 서비스의 QoS를 지원하기 위한 새로운 할당 알고리즘을 제안하였다. 제안한 알고리즘의 성능을 분석하기 위해 기존의 FCFS 방식의 상향 채널할당 방식과 QoS 지원 상향채널 할당방식의 성능을 시뮬레이션을 통해 비교하였다.

• The KIPS Transactions:PartC
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• v.9C no.1
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• pp.123-134
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• 2002

The requirement for QoS (Quality of Service) has become an important Issue as real-time or high bandwidth services are increasing, such as Internet Telephony, Internet broadcasting, and multimedia service etc. In order to guarantee the QoS of Internet application services, several approaches are being sought including IntServ (Integrated Service) DiffServ(Differentiated Srvices), and MPLS(Multi-Protocol Label Switching). In this paper, we describe the performance analysis of QoS guarantee mechanism using the DiffServ. To analyze how the DiffServ performance was affected by diverse input traffic models and the weight value in WFQ(Weighted Fair Queueing), we simulated and performed performance evaluation under a random, bursty, and self-similar input traffic models and for diverse input parameters. leased on the results of performance analysis, it was confirmed that significant difference exist in packet delay and loss depending on the input traffic models used. However, it was revealed that QoS guarantee is possible to the EF (expedited Forwarding) class and the service separation between RF and BE (Best Effort) classes may also be achieved. Next, we discussed the performance synthesis problem. (i. e. derived the conservation laws for a DiffServ networks, and analysed the performance variation and dynamic behavior based on the resource allocation (i.e., weight value) in WFQ.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.4
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• pp.17-27
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• 2007

The enhanced distributed channel access (EDCA) of IEEE 802.11e has been standardized for supporting Quality of Service (QoS) in wireless LANs. In the EDCA, support of QoS can be achieved statistically by reducing the probability of medium access for lower priority traffics. In other words, it provides statistical channel access rather than deterministically prioritized access to high priority traffic. Therefore, lower priority traffics affect the performance of higher priority traffics. Consequently, at the high loads, the EDCA does not guarantee the QoS of multimedia applications such as voice and video even though it provides higher priority. In this paper, we propose a simple and effective scheme, called deterministic priority channel access (DPCA), for improving the QoS performance of the EDCA mechanism. In order to provide guaranteed priority channel access to multimedia applications, the proposed scheme uses a busy tone for limiting the transmissions of lower priority traffics when higher priority traffic has data packets to send. Performance of the proposed scheme is investigated by numerical analysis and simulation. Our results show that the proposed scheme outperforms the EDCA in terms of throughput, delay, jitter, and drop under a wide range of contention levels.