• Journal of Korea Multimedia Society
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• v.11 no.3
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• pp.341-352
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• 2008

The dedicated line linked up with the internet maintains generally the efficiency of network by using Best Effort Model. But it is the problem that we allocate the higher bandwidth to services which request high bandwidth regardless of service types or purposes. To overcome this weak point, we use the Session QoS System which distinguish between business services such as E-mail, Web, etc. and non-business services. But, a recent session QoS system is not adequate to the environment similar to university, because that has many users who have various requests. In this paper, to satisfy various requirements of many user's in session QoS system which support services of research, education, business, etc., we analyze types of service in the environment of education and research network and propose a necessity of management strategies of session Qos system.

• Journal of KIISE:Information Networking
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• v.34 no.1
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• pp.73-80
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• 2007

This paper presents an approach to support dynamic QoS(Quality of Service) requirements of largely emerging SIP(Session Initiation Protocol) multimedia applications in broadband access networks. The topology of QoS-enabled broadband access networks and its operational model to support SIP QoS are firstly suggested. And then the procedures to bind QoS-enabled SIP signaling into an IP QoS mechanism are presented. In this paper, DiffServ-based IP QoS architecture is deployed due to the complexity problem of the other IntServ architecture, and COPS(Common Open Policy Service) and COPS-PR protocol based signaling mechanisms are used to support dynamic DiffServ QoS, correspondent with dynamic SIP QoS. The broadband access network is assumed to support rapidly expanding Metro Ethernet 802.1 D/Q QoS, and how to translate SIP QoS parameters into IP DiffServ classes and DiffServ classes into 802.1 D/Q QoS parameters is also presented in this paper.

• Journal of IKEEE
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• v.5 no.2 s.9
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• pp.136-145
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• 2001

As with appearing new applications that requires QoS guarantee such as VoIP, VPN in Internet, problems of IP QoS has been one of most important issues in next-generation Internet. IETF has proposed integrated services model(Int-Serv) and differentiated service(Diff-Serv) to supply IP QoS in Internet. Int-Serv model uses the state information of each IP flow, so satisfies QoS according to traffic characteristics, but increases the amount of flow state information with increasing flow number. Diff-Serv model uses PHP(Per Hop Behavior), and there are well-defined classes to provide differentiated traffics with different services according to delay and loss sensitivity. Diff-Serv model can provide diverse services in Internet because of having no the state and signal information of each flow. As MPLS uses the packet forwarding technique based-on label, it implements the traffic engineering in the networks easily. The MPLS can set up the path with different traffic parameters, and assign each path to particular Class of Services. Therefore it is possible to support the Diff-Serv model with well-defined classes. In this paper we investigate the performance improvement of Diff-Serv function in the MPLS network to guarantee class of services in Internet.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11B
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• pp.744-749
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• 2005

This paper proposes the prediction based QoS routing algorithm, PSS(Prediction Safety-Shortest) algorithm that minimizes network state information overhead and presumes more accurate knowledge of the present state of all the links within the network. We apply time series model to the available bandwidth prediction to overcome inaccurate information of the existing QoS routing algorithms. We have evaluated the performance of the proposed model and the existing algorithms on MCI networks, it thus appears that we have verified the performance of this algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9B
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• pp.760-773
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• 2003

The Internet is evolving from best-effort service toward an integrated or differentiated service framework with quality-of-service (QoS) assurances that are required for new multimedia service applications. Given this increasing demand for high bandwidth Internet with QoS assurances in the coming years, an IP/MPLS-based control plane combined. with a wavelength-routed dense-wavelength division multiplexing (DWDM) optical network is seen as a very promising approach for the realization of future re-configurable transport networks. This paper proposes a differentiated lambda establishment process for QoS guarantees based on the differentiated MPLS service (DMS) model. According to the QoS characteristics of wavelength in optical links and the type of used Optical Cross-Connect (OXC) nodes in DWDM next generation optical Internet backbone network, a differentiated wavelength assignment strategy that considers QoS recovery capability is also suggested.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7B
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• pp.653-663
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• 2002

UMTS/GPRS has its own QoS architecture, but additionally needs to support IP-QoS to provide Internet services. This paper describes an IP-QoS provisioning mechanism in the MPLS-based UMTS/GPRS network. We propose a QoS framework that includes the functional architecture of the MPLS-based GPRS networks and the efficient scheduling mechanism based on Diffserv model. The proposed scheduling mechanims is especially focused on the QoS support for real-time services. It also includes a new buffer management scheme that combines the priority queuing and weighted round robin method. The ns-2 simulator has been used to verify the validity of the proposed scheduling method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.303-309
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• 2005

This paper will suggest how can we guarantee terminal QoS like ship waiting time ratio and ship residing time applying RFID(Radio Frequence Identification) technology, raising up rapidly as a fundamental solution of new growing industry, to port information system. Also, lead time of whole port logistics can be decreased for reduction of loading & discharging time resulted from productivity improvement of Twinlift G/C(Gantry Crane) and Y/T(Yard Tract) etc as applying RFID technology to terminal operation. The purpose of this paper is suggesting of new business model of u-Port that port QoS can be guaranteed from mutual agreement of each terminals RFID technology applied and focusing on the implementation plan.

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.257-260
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• 2001

As today's network infrastructure continues to grow and DiffServ IP networks ate now available to provide various levels of flexible QoS services. DiffServ guarantees good scalability but shows dynamic QoS dependent on network traffic loads. Therefore, in this paper, we investigate the dynamics of DiffSev QoS and present analytical model to estimate the allowable traffic load under the given network conditions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.8
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• pp.1899-1906
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• 1998

In ATM switching system link bandwidth is one of the improtant resources. Thus ATM switching system must allocate the bandwidth to the users efficiently and guarantee the QoS. Especially to guarantee the QoS of the VBR traffic source such as video, users must declare the traffic characteristics and QoS expectations using UPC parameters. The CAC can use two multiplexig models in variation to link capacity and connection number. One is loseless multiplexing model; the second is a statistical multiplexing model. The loseless multiplexing model performs best when the number of mutiplexed sources is small, but as the number of multiplexed sources is increase the CAC must use the statistical multiplexing model. In this paper, the statistical multiplexing models are studied, which are suitable for high capacity ATM link on VBR traffic sources. The satistical multiplexing model and the loseless multiplexing model are combined. In statistical model we map the UPC parameters provided by new VBR connection to appropriate source traffic model. In the high capacity ATM link, as the connection number increases, the statical multiplexing gain increases.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1616-1640
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• 2006

In this paper, we deal with a network optimization problem arising from the deployment of Ethernet-based BcN access network. BcN convergence services require that access networks satisfy QoS measures. BcN services have two types of traffics: stream traffic and elastic traffic. Stream traffic uses blocking probability as a QoS measure, while elastic traffic uses delay factor as a QoS measure. Incorporating the QoS requirements, we formulate the problem as a nonlinear mixed-integer programming model. The proposed model seeks to find a minimum cost dimensioning solution, while satisfying the QoS requirement. We propose tabu search heuristic algorithms for solving the problem, and simulate tabu result. We demonstrate the computational efficacy of the proposed algorithm by solving a network design problem.