• Journal of Korea Multimedia Society
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• v.10 no.9
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• pp.1153-1164
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• 2007

One of the most challenging technical issues in mobile communication for multimedia is Quality of Service (QoS) management of handover calls. This paper proposes a 2-level handover control system to copy with this problem. A 2-level handover control system consists of resource reservation and call admission control modules. The resource reservation module divides the network resource into Hard and Soft reserved resource. The Hard reserved resource is only for the handover calls while the Soft reserved resource is for both the handovers and the new calls. And also, the resource reservation module classifies handovers into primary and secondary handovers based on often they occur. The call admission control module deals with the primary and secondary handover calls in different ways. The new calls can use Soft reserved resource only if there is sufficient amount available in the Hard reserved resource. Proposed system is evaluated using an M/M/c/c queueing model. It is shown that proposed system allows more efficient utilization of network resource without degrading QoS comparing with the legacy handover control systems.

• 전자공학회논문지 IE
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• v.45 no.3
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• pp.50-55
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• 2008

In CDMA system, the number of mobile stations which can be served simultaneously in a base station is limited by the amount of total interference received. Considering the facts, the call admission control method using the effective bandwidth concept is employed in this paper. The bandwidth for a new call and a handoff call is allocated by considering the number of mobile station being served and dynamically assigned by taking account of the blocking rate of new calls and the dropping rate of handoff calls. Also, there is reserved resource for handoff call. We analyze the performance of system according to reserved resource by a simulation study. The more a resource reserved, the less it is the dropping rate of handoff.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.401-404
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• 2003

In most resource reservation strategies, which give higher priorities to handoff calls over new calls, new calls are often blocked even though there is plenty of available reserved resource. This causes inefficient resource utilization, especially when there are not so many handoff attempts. In this paper, we propose a new reservationstrategy called soft reservation in which new calls can be allocated to the reserved resource while maintaining the QoS of handoff acceptable. Using an M/M/c/c queuing model, we can see that the proposed strategy provides better performance than the conventional reservation strategy in terms of blocking probability of new call and dropping probability of handoff calls.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.5029-5035
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• 2010

This paper proposes a scheme to maximize traffic capacity for supporting mobile multimedia services. For a handoff session, we suggest a novel resource reservation scheme to adjust the number of reserved resources in macrocell, depending on the number of saturated microcells. The proposed schemes are able to accommodate much more mobile sessions in the microcell and significantly reduce the blocking probability in the macrocell at the expense of the small increment of a forced termination in the microcell. Therefore, our system is more flexible to the increase of traffic in macrocell.

• Journal of Advanced Navigation Technology
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• v.11 no.3
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• pp.252-258
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• 2007

There has been a lot of research done in scheme guaranteeing user's mobility and effective resources management to satisfy the requested by users in the wireless/mobile networks. In this paper, we propose a predictive resource allocation scheme based on ARMA(Auto Regressive Moving Average) prediction model to meet QoS requirements(handoff dropping rate) for guaranteeing users' mobility. The proposed scheme predicts the demanded amount of resource in the future time by ARMA time series prediction model, and then reserves it. The ARMA model can be used to take into account the correlation of future handoff resource demands with present and past handoff demands for provision of targeted handoff dropping rate. Simulation results show that the proposed scheme outperforms the existing RCS(Reserved channel scheme) in terms of handoff connection dropping rate and resource utilization.

• 전자공학회논문지 IE
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• v.46 no.3
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• pp.42-47
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• 2009

In CDMA system, the call admission control method using the variable effective bandwidth concept is employed in this paper. The bandwidth for a new call and a handoff call is allocated by considering the number of mobile station being served and dynamically assigned by taking account of the blocking rate of new calls and the dropping rate of handoff calls. There is reserved resource for handoff call. In the case radio resource is insufficient, a new call and a handoff call stand by in buffer for constant time. When radio resource come about, the waiting call is allocated the resource. I analyze the performance of system according to existence and nonexistence of buffer by a simulation study.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9A
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• pp.736-745
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• 2003

Resource allocation methods are proposed to address the problem of how flexibly allocate limited wireless resource to high bandwidth demanded realtime class with certain QoS guarantees in CDMA/TDD systems. In this method, A reserved access scheme is used for allocating the resource to realtime and non-realtime class respectively. We also propose a slot allocation algorithm for the CDMA/TDD system, which can prevent the performance degradation due to the interlink interference in each cell. Our framework is able to guarantee QoS continuity of realtime class and carry the maximum number of non-realtime subscriber. System performance of proposed method is evaluated by considering transmission delay, channel utilization and data loss, assuming a practical multi-cell environment and a multimedia service model. Our simulation results demonstrate the significant performance improvement.

• 전자공학회논문지 IE
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• v.48 no.4
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• pp.47-52
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• 2011

In this paper, we analyse the performance of cellular system for call admission method considering to various service types. The call admission control method using the effective bandwidth concept is employed in this paper. In addition, the bandwidth for a new calls and a handover calls is allocated by taking account of the blocking rate of new calls and the dropping rate of handover calls. We reserved wireless resource and used waiting buffer for hanover calls. We simulated using computer for the performance analysis of system.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.05a
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• pp.125-126
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• 2013

클라우드 컴퓨팅 환경에서, 모든 IT 자원은 가상화된 자원(Virtualized Resource)의 형태로 클라우드 서비스 사용자에게 제공되고 사용자는 자신이 점유한 시간만큼만 자원 사용 비용을 클라우드 서비스 제공자에게 지불하면 된다. 서비스 제공자는 서비스 사용자가 처리하고자 하는 어플리케이션의 특성을 고려하여 온디맨드(On-demand) 및 예약형(Reserved) 가상 자원 가격 정책을 제공한다. 따라서 서비스 사용자는 서비스 제공자의 제안 가격 정책을 기반으로 어플리케이션의 처리 예상 시간 및 지불 비용을 고려하여 효율적인 자원 요청 계획을 수립해야 한다. 본 논문에서는 클라우드 브로커링 시스템(Cloud Brokering System)을 통해 자원 할당 정책을 수행하여 연동된 다중 사용자에게 비용 효율적인 자원을 제공하는 구조 및 프로세스를 소개한다.

• Journal of KIISE:Information Networking
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• v.33 no.3
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• pp.247-256
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• 2006

Among the resource provisioning mechanisms for the hose based Virtual Private Network (VPN) Quality of Service (QoS ), VPN-specific state provisioning allows the service provider to obtain highest resource multiplexing gains. However, dynamic and automatic resource reservation for the VPN-specific state provisioning is difficult due to the lack of appropriate resource reservation protocol. Furthermore, users of a VPN may experience unfair usage of resources among themselves since the reserved resources of a VPN are shared by the VPN users in a similar way that the traditional LAN bandwidth is shared by the attached hosts. In this paper, we propose a resource reservation protocol and a traffic service mechanism, which not only enable dynamic and automatic resource reservation according to the VPN-specific state provisioning algorithm, but also enforce the fair usage of reserved resources among the users of a VPN in case of congestion.