• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6A
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• pp.386-396
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• 2003

Recently, mobile communication systems have supported various services including internet from voice centric service as they evolve toward 3G. To accommodate the increasing number of users, an AAL2 multiplexing scheme is introduced in the UTRAN tub interface for link efficiency. However, limited radio resources and different requirements of various services make it difficult to guarantee the QoS requirements at radio access networks. The conventional AAL2/ATM multiplexing systems focused on the multiplexing efficiency of voice anddata services and QoS issues of real time and non real time services. In this paper, we classfy various services according to QoS requirements and propose AAL2/ATM multiplexing schemes using statistical multiplexing and scheduling with a rather simple structure to guarantee the given requirements. Simulation results show that the proposed schemes perform better than the conventional schemes to guarantee QoS requirements of various services.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2A
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• pp.186-195
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• 2010

For the fast target base station channel decision in WiMAX networks, fast group scanning scheme was suggested, in which mobile stations in proximity of each other form a group and scan the candidate channels dispersively. However, the previous group scanning scheme does not consider the different QoS requirements of each MS in a group. In this paper we propose the enhanced group scanning scheme, so-called QoS-aware group scan scheduling scheme, that makes mobile stations in a group scan the candidate channels without deteriorating the QoS requirements. We introduce the QoS-aware channel scanning concept of a individual mobile station and show the different scanning latencies due to the different QoS requirements. With the help of the efficient channel allocation by the serving BS, in the proposed scanning scheme, a mobile station with relatively higher QoS in a group scans less amount of candidate channels than the others with relatively lower QoS, while the mobile stations in a group still guarantees the fast target base station decision. The performance results show that our proposed scanning scheme results in the fast target base station decision while considering the QoS requirements of each MS.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.2922-2931
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• 1999

In this paper, we propose a new framework for scalable media object to adapt the various QoS requirements in the heterogeneous networking environment. An MPEG-2 video is split into a set of scalable media objects in terms of temporal scaling and fidelity scaling. The portion of the scalable media objects is selectively delivered to adapt the QoS requirement. This framework can satisfy the various QoS requirements on bandwidth, even though the clients share a multipoint channel. By analysis on the rate-distortion characteristics of scalable media object framework, we shows our approach is feasible to support the various QoS requirements.

• Journal of the Korea Society of Computer and Information
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• v.6 no.4
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• pp.154-162
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• 2001

In this paper, we investigate the scheduling algorithm of router system for Internet service based on the qualify-of-service (QoS) level of the input source traffics. We suggest an approprite scheduling algorithm in order to satisfy their QoS requirements for the loss-sensitive traffic and delay-sensitive traffic. For this purpose, we first study the service requirements of the multiplexer in Internet and the definition of QoS based on the ITU-T white recommendations. Second. we suggest a functional architecture of the multiplexer and the scheduling algorithm to satisfy various QoS requirements for Internet service. Finally. the performance measures of interest, namely steady-state packet loss probability and average delay, are discussed by simulation results.

• Journal of the Korea Computer Industry Society
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• v.2 no.9
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• pp.1225-1232
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• 2001

In this paper, we investigate the scheduling algorithm of router system for Internet services on large scale ATM networks based on the quality-of-service(QoS) level of the input source traffics. We suggest an approprite scheduling algorithm in order to satisfy their QoS requirements. For this purpose, we first study the service requirements of the multiplexer in Internet. Second, we suggest functional architecture of the multiplexer for real time services and the scheduling algorithm to satisfy various QoS requirements. Finally, the performance measures of interest, namely steady-state average delay time and fairness of network resources, are discussed by simulation results.

• ETRI Journal
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• v.29 no.1
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• pp.120-123
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• 2007

In this letter, we address the problem of resource allocation with efficiency and quality of service (QoS) support in uplink for a wireless CDMA network supporting real-time (RT) and non-realtime (NRT) communication services. For RT and NRT users, there are different QoS requirements. We introduce and describe a new scheme, namely, traffic aided uplink opportunistic scheduling (TAUOS). While guaranteeing the different QoS requirements, TAUOS exploits the channel condition to improve system throughput. In TAUOS, the cross-layer information, file size information, is used to improve fairness for NRT users. Extensive simulation results show that our scheme can achieve high system throughput in uplink wireless CDMA systems, while guaranteeing QoS requirements.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.497-507
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• 2018

Tactical networks are evolving into an All-IP based network for network centric warfare(NCW). Owing to the flexibility of IP based network, various military data applications including real-time and multi-media services are being integrated in tactical networks. Because each application has diverse Quality-of-service(QoS) requirements, it is crucial to develop a QoS provisioning method for guaranteeing QoS requirements efficiently. Conventionally, differentiated services(DiffServ) have been used to provide a different level of QoS for traffic flows. However, DiffServ is not designed to guarantee a specific requirement of QoS such as delay, loss, and bandwidth. Therefore, it is not suitable for military applications with a tight bound of QoS requirements. In this paper, we propose a multi-layer network virtualization scheme that allocates traffic flows having different QoS requirements to multiple virtual networks, which are constructed to support different QoS policies such as virtual network functions(VNFs), routing, queueing/active queue management(AQM), and physical layer policy. The experiment results indicate that the proposed scheme achieves lower delays and losses through multiple virtual networks having differentiated QoS policies in comparison with conventional networks.

• Journal of Internet Computing and Services
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• v.5 no.6
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• pp.11-20
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• 2004

Proportional Fair (PF) share policy has been adopted as a downlink scheduling scheme in CDMA2000 l×EV-DO standard. Although It offers optimal performance in aggregate throughput conditioned on equal time share among users, it cannot provide a bandwidth guarantee and a strict delay bound. which is essential requirements of real-time (RT) applications. In this study, we propose a new scheduling policy that provides quality-of-service (QoS) guarantees to a variety of traffic types demanding diverse service requirements. In our policy data traffic is categorized Into three classes, depending on sensitivity of Its performance to delay or throughput. And the primary components of our policy, namely, Proportional Fair (PF), Weighted Fair Queuing (WFQ), and delay-based prioritized scheme are intelligently combined to satisfy QoS requirements of each traffic type. In our policy all the traffic categories run on the PF policy as a basis. However the level of emphasis on each of those ingredient policies is changed in an adaptive manner by taking into account the channel conditions and QoS requirements. Such flexibility of our proposed policy leads to offering QoS guarantees effectively and. at the same time, maximizing the throughput. Simulations are used to verify the performance of the proposed scheduling policy. Experimental results show that our proposal can provide guaranteed throughput and maximum delay bound more efficiently compared to other policies.

• Annual Conference of KIPS
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• 2014.11a
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• pp.227-230
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• 2014

LTE 3GPP standard defines several QCI (QoS Class Identifier) classes to provide differential QoS, depending on the requirements of different user applications.These QCI values have been characterized in terms of priority, packet loss and delay budget. In spite of the availability of this robust QoS framework in LTE, there is no such scheduling algorithm that has its working principle based on this framework. The responsibility of fulfilling the user requirements, while satisfying the service class requirements is left upon the cellular service provider and it is an open issue at present. To solve this problem, we have proposed a MAC scheduler, which defines the priority of different users based on their bearer specification and provides desired QoS in terms of the achieved throughput through the resource block allocation based on calculated user priority.

• The Journal of the Korea Contents Association
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• v.10 no.3
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• pp.80-91
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• 2010

Due to the convergence of broadcasting and communications, IPTV services are spotlighted as the that next-generation multimedia services. IPTV services should have functionality such as unlimited channel capacity, extension of media, QoS awareness and are required increasing traffic and quality control technology to adapt the attributes of IPTV service. Consequently, flow based quality control techniques are needed. Therefore, many studies for providing Internet QoS are performed at IETF (Internet Engineering Task Force). As the buffer management mechanism among IP QoS methods, active queue management method such as RED(Random Early Detection) and modified RED algorithms have proposed. However, these algorithms have difficulties to satisfy the requirements of various Internet user QoS. Therefore, in this paper we propose the Flow based AQM(Active Queue Management) algorithm for the multimedia services that request various QoS requirements. The proposed algorithm can converge the packet loss ratio to the target packet loss ratio of required QoS requirements. And we present a performance evaluation by the simulations using the ns-2.