• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.3
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• pp.446-452
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• 2006

In this paper, I evaluated the throughput of various multimedia traffic by using computer simulation over wireless LAN environment based on 802.11e MAC protocol. The number of mobile terminals which generate various traffic and have different Internet QoS varies to improve the reliability of performance evaluation by simulation. Therefore, we investigate throughput of traffic that each mobile terminal generates. I expect that the result of study will be utilized as a fundamental data to control priorities of various types of traffic in case of formulating a scheduling policy supporting a variety of Internet QoS over wired and wireless networks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.9
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• pp.801-810
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• 2014

In this paper, we will provide a way to grant a differentiated service rate that is according to priorities of WLP device and WUSB/DRD transfer mode by improving D-SoQ that considers existing QoS of WiMedia WSS environment based on UWB technology. The proposed method makes it possible to differentiate SoQ performance and throughput, based on priority of traffic streams.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6B
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• pp.433-442
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• 2012

We have proposed a solution to multicast services and an advanced quality of service (QoS) mechanism on a packet transport system (PTS) based on PBB-TE. The point-to-multipoint (PtMP) connection in the PBB-TE system have been realized by grouping point-to-point (PtP) PTL trunks and mapping a BSI onto the PtP PTL trunks using a multicast backbone destination address. To provide end-to-end QoS of the PtMP services, the hierarchical QoS scheme for backbone service instances and connection-oriented paths has been implemented in the PTS. For providing different capabilities for service selection and priority selection, the PTS offers to customers three basic types of the port-based, C-tagged, and S-tagged service interface defined by the IEEE 802.1ah. To offer to customers different capabilities of the layer 3 applications and services, moreover, an IP-flow service interface have been added. In order to evaluate traffic performance for PtMP services in the PTS, the PtMP throughputs for the link capacity of 1 Gbps at the four service interfaces were measured in the leaves of the ingress edge node, the transit node, and the egress edge node. The throughputs were about 96 % because the B-MAC overhead of 22 bytes occupies 4% of the 512-byte packet. The QoS performance is ability to guarantee an application or a user a required bandwidth, and could be evaluated by the accuracy of policing or shaping. The accuracy of the policing scheme and the accuracy of the shaping scheme were 99% and 99.3% respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.971-989
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• 2015

With the development of cloud computing, more and more Web services are deployed on geo-distributed datacenters and are offered to cloud users all over the world. Through service composition technologies, these independent fine-grain services can be integrated to value-added coarse-grain services. During the composition, a number of Web services may provide the same function but differ in performance. In addition, the distribution of cloud datacenters presents a geographically dispersive manner, which elevates the impact of the network on the QoS of composite services. So it is important to select an optimal composition path in terms of QoS when many functionally equivalent services are available. To achieve this objective, we first present a graph model that takes both QoS of Web services and QoS of network into consideration. Then, a novel approach aiming at selecting the optimal composition path that fulfills the user's end-to-end QoS requirements is provided. We evaluate our approach through simulation and compare our method with existing solutions. Results show that our approach significantly outperforms existing solutions in terms of optimality and scalability.

• The KIPS Transactions:PartC
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• v.8C no.1
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• pp.41-50
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• 2001

With growth of Internet, real time multimedia application services require guarantee of QoS (Quality of Service). However, the existing Internet based on best-effort service is not enough to support those services, so MARS model to support IP multicast over ATM networks and RSVP to provide heterogeneous QoS by resource reservation scheme are proposed. As a simulation result, it is proved that processing delay of MARS is increased and success of resource reservation is decreased as a number of QoS change request of a receiver is increased. Therefore, it is important to provide heterogeneous QoS that distribute a load of MARS caused by convergence of messages and efficiently manage the resource of network as to find out scale of receivers and frequency of QoS change request.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.1
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• pp.17-23
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• 2007

The home network has been revitalized due to the emergence of the high-speed broadband network and explosive increases of the home network services. Especially multicast based high-definition (HD) IPTV service is on high demand from both Internet service provider (ISP) and users. In order to provide high quality HD IPTV service without packet loss and delay, the ISP utilizes various network QoS mechanisms. Due to the misleading fact, that the home gateway is considered as an end terminal in terms of the ISP's viewpoint, the ISPs can not guarantee the end-to-end QoS within the scope of the current home network architecture. Therefore, an independent QoS guaranteed mechanism should be considered within the home network domain. As the home gateway manages both private home and public access network within the home network, we propose and implement a novel QoS mechanism for the multicast based HD IPTV service over the home gateway. In order to provide QoS guaranteed HD IPTV service, the proposed mechanism classifies the packets, manages home network bandwidth resources, and executes call admission control using the channel join message. Also, we utilize layer 2 multicast packet forwarding scheme to improve the overall performance of the home network services. Through the experiments of implementing the multicast based HD IPTV services, we will verify the efficiency of the proposed mechanism.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.150-153
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• 2001

Today Internet is only Best-Effort service. During the past few years, new types of internet applications which require performance beyond the best-effort service that is provided by the current internet have emerged. These applications required QoS(Quality of Services) guarantee and Security between end-to-end. In this paper simulations Differentiated Services that IETF(Internet Engineering Task Forte) has proposed one of QoS(Quality of Services) guarantee VPN(Virtual private Network) using QoS(Quality of Services) guarantee and IP Security between end-to-end.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.2A
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• pp.61-65
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• 2005

We propose a soft QoS-based borrowing scheme for call admission control(CAC) in DVB-RCS(Digital Video Broadcast-Return Channel via Satellite). Some of the ongoing calls temporarily and fairly release bandwidths that can be used to accommodate a new call in an overloaded satellite network. The amount of bandwidth borrowed from each call is proportional to each user's critical bandwidth ratio, one of parameters for soft QoS mechanism. Simulation results show that the proposed scheme improves the system performance in terms of call blocking probability and bandwidth utilization.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3367-3378
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• 1999

ATM technology, which acts as a representative high-speed bandwidth technology, plays an important role in Internet environment. ATM network, supporting QoS(Quality of Service) and various traffic characters in high speed, configures many VPC(Virtual Path Connection)/VCC(Virtual Channel Connection). It is important to guarantee the QoS of each connection and it is necessary for the network manager to search element affecting the QoS of VPC/VCC and to control ATM network correctly. In the paper, the management information of VPC/VCC, that ATM network manager Using the fault notification for ATM switch, we can manage the configuration, fault and performance of ATM network. Thus, we extracted the configuration, fault and performance monitoring item from the ATM-MIB and SNMP M4 Network Element View MIB. And we designed the ATM network configuration, fault and performance management system based on the extracted item.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5B
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• pp.304-309
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• 2005

In this paper, we propose a localized Adaptive QoS Routing using TD method and evaluate performance of various exploration methods when path is selected. Expecially, through extensive simulation, the proposed routing algorithm and exploration method using Exploration Bonus are shown to be effective in significantly reducing the overall blocking probability, when compared to the other path selection method(exploration method), because the proposed exploration method is more adaptive to network environments than others when path is selected.