• Journal of KIISE:Computing Practices and Letters
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• v.6 no.1
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• pp.36-44
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• 2000

In this paper, we describe the developing of a tool which supports both multimedia presentation with user's participation through a high speed network and authoring of various media using a single authoring tool. To support real-time synchronous multimedia presentation, we adopt dynamic synchronization method and adaptive transmission algorithm for synchronizing data transfer rate between sender and receiver using buffer management algorithm based on QoS parameters. And we also allow user's participation in the presentation using TRSG(Temporal Relationship Specification Graph) model. Finally, the proposed tool supports the minimal level of QoS and its continuous play-out using event auditing threads which control the current state of a multimedia presentation continuously by monitoring of negative factors effecting on QoS, and synchronization.

• Journal of the Korea Society of Computer and Information
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• v.15 no.8
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• pp.79-87
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• 2010

It is widely accepted that the coverage with high user densities in mobile multimedia environments can only be achieved with small cell such as micro- and pico-cell. If handover events occur during the transmission of multimedia, the efficient resource reservation and handover methods are necessary in order to maintain the same QoS of transmitted multimedia traffic because the QoS may be defected by some delay and information loss. In this paper, we propose a resource allocation method in the next generation mobile communication systems, in which the resource allocation process has a tight relation with call admission, call load, and packet scheduling. The simulation results show that our proposed method provides a excellent performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.7
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• pp.1250-1256
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• 2001

A resource management scheme for ad hoc wireless local area networks (AWLAN's) is presented. This scheme combines distributed resource management scheme and orthogonal frequency division multiplexing-code division multiple access(OFDM-CDMA) technique to support multimedia services with QoS guarantees. The performance evaluation has done in terms of blocking rates and QoS loss probability.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.4A
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• pp.451-463
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• 2000

In this paper, we design the radio data link protocols with QoS provisioning for mobile multimedia such as voice, data, and video in CDMA-based ATM networks, and analyze the performance of the data link protocols. To support mobile multimedia traffic, the required QoS parameters and the characteristics are analyzed, and wireless protocol stacks are proposed for integrating the wireless access network and ATM transport networks, and radio data link protocols are designed for provisioning QoS Control. The data link protocols are analyzed assuming that the system is supporting 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 radio link protocols are efficient to support QoS requirements while the complexities are increased.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.549-552
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• 2002

복잡하고 거대한 통신망을 효율적으로 구성하고 운용 관리하기 위해 ITU-T에서는 TMN 망관리 국제표준을 정하고 있다. 그러나 TCP/IP 기반의 인터넷 망에서는 TMN보다 간단하게 정의되어 있는 SNMP를 이용해 MIB를 기반으로 망 요소(network element) 제어만을 하고 있다. 인터넷 망에서 멀티미디어 데이터 교환 서비스를 수용하면서, IP 망 설계 초기에 고려하지 않았던 서비스품질(QoS)을 제공하기 위해 IntServ, DiffServ 프로토콜 등을 정의하고 있다. 이렇게 QoS를 제공하기 위한 인터넷 망은 단순한 SNMP 만으로는 관리될 수 없다. 그러나 아직까지 이에 적합한 망관리 모델이 정립되지 못한 상태인 바, 본 논문에서는 정책을 기반(policy-based)으로 하여 QoS 서비스를 위한 자원 할당을 dynamic하게 제공할 수 있도록 하는 QoS 인터넷 망관리 모델을 제안한다. 이 모델은 TMN의 관리계층 구조에 맞도록 구성되어 있다.

• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.71-73
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• 2004

Recently many peoples served multimedia data from Internet. But characteristic of multimedia-object about that effect on weight and transport-time causes Streaming Application is restricted to high-quality-service. This research propose the Quality-of-service(QoS) supporting for Home Gateway that behaving Routing and media platform equipment, using CBQ Scheduling scheme. The QoS Supporting for Multimeda Service that using general Rouging policy is difficult because media platform locate in Home Gateway. Therefore this research propose Routing mechanism to QoS support of media platform located in Gateway using TCP based CBQ Control.

• Journal of Korea Multimedia Society
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• v.11 no.12
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• pp.1730-1738
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• 2008

Quality of Service (QoS) Guarantees grant ways for service providers to establish service differentiation among subscribers. On the other hand, service subscribers are also assured the level of service they paid for. In addition, the efficient level of service quality can be selected according to the subscribers' needs thus ensuring efficient use of available bandwidth. While network utility optimization techniques assure certain QoS metrics, a number of situations exist where some QoS goals are not met. The optimality of the network parameters is not mandatory to guarantee specified QoS levels. This paper proposes a joint data rate and power control scheme that guarantees service contract QoS level to a subscriber using Goal Programming. In using goal programming, this paper focuses on finding the range of feasible solutions as opposed to solving for the optimal. In addition, in case no feasible solution is found, an acceptable compromised solution is solved.

• Proceedings of the IEEK Conference
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• summer
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• pp.395-399
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• 2004

We present modality conversion as an effective means for QoS management. We show that modality conversion, in combination with content scaling, would give a wider range of adaptation to support QoS at media level. Here, we consider modality conversion with respect to resource constraint and human factor. To represent modality conversion as well as content scaling, we present the overlapped content value (OCV) model that relates the content value of different modalities with resources. The specification of user preference on modality conversion is divided into qualitative and quantitative levels. The user preference is then integrated into the OCV model so that modality conversion correctly reflects the user's wishes. For the conversion of multiple contents, an optimization problem is formulated and solved by dynamic programming. The experiments show that the proposed approach is efficient to be applied in practice.

• 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).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6A
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• pp.351-360
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• 2003

To provide good-quality services of multimedia in wireless mobile networks, QoS for multimedia traffic should be guaranteed. However, since the existing QoS guaranteed schemes are designed for fixed networks, they are inadequate in the wireless network environments. Recently, as the size of cells like micro cell or pico cell becomes smaller. Mobile hosts on micro cellular networks, change their location frequently. It causes many drawbacks such as delayed delivery, packet losses and signaling overheads. Because the existing schemes supporting interoperability between RSVP and Mobile If are designed for macro cell environments. Their uses in micro cellular networks can be restricted. In this paper, we propose the CRSVP(Cellular RSVP Protocol) which supports QoS in micro cellular network environments.