• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7B
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• pp.613-627
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• 2004

In this paper, we propose an Aggregate Fairness Maker (ARM) required for an Edge router to improve fairness of throughput among the flows of Assured Service in DiffServ with different round trip time (RTT) and we propose a user flow Three Color Marker (uf-TCM) as a flow marker that marks packets from the flow as green, yellow, or red. A yellow packet is the packet that consumes loss token in uf-TCM as well as that is demoted green packet in AM due to disobey the aggregate traffic profile. The proposed AFH promotes yellow packet to green packet or demotes green packet to yellow packet through the fair method without per-flow management, and it improves the feirness of throughput among the flows as well as link utilization. A yellow packet and a red packet have the same drop precedence at Core Router in our scheme. So we can use the RIO buffer management scheme. We evaluated the performance of our proposed AFM and the REDP Marker that was proposed to improve fairness without per-flow management. Simulation results show that, compared with the REDP marker, proposed AFM can improve performance of throughput fairness among the flows with different RTT and link utilization under the over-provisioning, exact-provisioning, and under-provisioning network environments at Multiple DiffServ domains as well as at Single DiffServ domain.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.767-772
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• 2005

The Internet is a packet switched network which offers best-effort service, but current IP network provide enhanced services such Quality of Services, Virtual Private Network (VPN) services, Distribute Firewall and IP Security Gateways. All such services need packet classification for determining the flow. The problem is performing scalable packet classification at wire speeds even as rule databases increase in size. Therefore, this research offer packet classification algorithm that increase classifier performance when working with enlarge rules database by rearrange rule structure into Bitmap Intersection Lookup (BIL) tables. It will use packet's header field for looking up BIL tables and take the result with intersection operation by logical AND. This approach will use simple algorithm and rule structure, it make classifier have high search speed and fast updates.

• ETRI Journal
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• v.26 no.5
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• pp.391-396
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• 2004

In this paper, we propose a packet scheduling discipline called packet loss fair scheduling, in which the packet loss of each user from different real-time traffic is fairly distributed according to the quality of service requirements. We consider an orthogonal frequency division multiple access (OFDMA) system. The basic frame structure of the system is for the downlink in a cellular packet network, where the time axis is divided into a finite number of slots within a frame, and the frequency axis is segmented into subchannels that consist of multiple subcarriers. In addition, to compensate for fast and slow channel variation, we employ a link adaptation technique such as adaptive modulation and coding. From the simulation results, our proposed packet scheduling scheme can support QoS differentiations while guaranteeing short-term fairness as well as long-term fairness for various real-time traffic.

• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.65-67
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• 2004

Change of state of Channel between two wireless terminals which is caused by noise and multiple environmental conditions for happens frequently from the Wireles Network. So, When it is like that planning a wireless network protocol or performance analysis, it follows to change of state of time-varying channel and packet the analysis against a transmission efficiency is necessary. In this paper, analyzes transmission time of a packet and a packet in a time-varying and packet based Wireless Network. To reflecte the feature of the time-varying channel, we use a Signal Flow Graph model. From the model the mean of transmission time and the mean of queue length of the packet are analyzed in terms of the packet distribution function, the packet transmission service time, and the PER of the time-varying channel.

• Journal of Korea Multimedia Society
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• v.10 no.12
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• pp.1622-1631
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• 2007

To realize the wireless packet scheduler which efficiently considers both the effect of adaptive modulation and coding (AMC) scheme due to variable wireless communication channel information from physical layer and the QoS differentiation of multimedia services from internet protocol (IP) layer, this paper proposes a new downlink AMC-based priority queuing (APQ) scheduler which combines AMC scheme and service priority method in multimedia services at the same time. The result of numerical analysis shows that the proposed APQ algorithm plays a role in increasing the number of services satisfying the mean waiting time requirements per each service in multimedia services because the APQ scheme allows the mean waiting time of each service to be reduced much more than existing packet scheduler having only user selection processor.

• Proceedings of the IEEK Conference
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• 2001.06a
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• pp.301-304
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• 2001

This paper presents a system for a billing system that can be used to motet dynamic priority users in IntServ operation over DiffServ network. Our billing system is designed to authentication, accounting, metering using Remote Authentication Dial In User Service (RADUS). we present packet pricing model of three different service classes which is Best, Good, Default service in IntServ operation over DiffServ network. The packet pricing model can present users with prices and charges in a way that encourages efficient network use. In this model, the RSVP is used, which is resource management to QoS routing function in the IntServ network.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.05a
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• pp.1-4
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• 2005

Information communication environment integrates communication, broadcasting and internet, and Digital Convergence service emerges in result. Thus, the effective routers are needed so that they can transmit a huge number of data to core internet through appropriate base center. Therefore, the network guaranteeing QoS in transport layer supports interoperability with different wireless networks. So as to users receive necessary information anywhere seamlessly, the network architecture focuses on packet transmission and it is efficient for the control layer switches and controls packets between different networks. Since individual users take advantage of different services and data, the effective router architecture must be designed. Hence in this paper we design monitoring technique to solve security problem and to support premium service to ultimate users. Thereafter, we run opnet simulation and show the improvement of proposed router architecture.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.9B
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• pp.1272-1280
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• 2010

WFQ (Weighted Fair Queuing) provides not only fairness among traffic flows in using bandwidth but also guarantees the Quality of Service (QoS) that individual flow requires, which is why it has been applied to the resource reservation protocol (RSVP)-capable router. The RSVP allocates an enough resource to satisfy both the rate and end-to-end delay requirements of the flow in condition of no packet loss, and the WFQ guarantees those QoS requirements with the allocated resource. In a practice, however, most QoS-guaranteed services, specially the Voice of IP, allow a few percent of packet loss, so it is strongly desired that the RSVP and WFQ make the best use of this allowable packet loss. This paper enhances the WFQ to allow packet loss and investigates its performance. The performance evaluation showed that allowing the packet loss of 0.4% can improve the flow admission capability by around 40 percent.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.45-48
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• 2002

This paper presents a QoS-guaranteed traffic control system which supports QoS of realtime packet transmission for the multimedia communication. The traffic control system presented in this paper applies the integrated service model and provides QoS o(packet transmission by means of determining the packet transmission rate with the policy of network manager and the optimal resource allocation according to the end-to-end traffic load. It also provides QoS for the realtime packet transmission through the AWF2Q+ Scheduling algorithm and per-class queuing method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3502-3509
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• 2010

Streaming service in the wireless mobile network environment has been a very challenging issue due to the dynamic uncertain nature of the channels. Overhead such as congestion, latency, and jitter lead to the problem of performance degradation of an adaptive multi-streaming service. This paper proposes a AMSS (Adaptive Multi-level Streaming Service) mechanism to reduce the performance degradation due to overhead such as variable network bandwidth, mobility and limited resources of the wireless mobile network. The proposed AMSS optimizes streaming services by: 1) use of fuzzy similarity metric, 2) minimization of packet loss due to buffer overflow and resource waste, and 3) minimization of packet loss due to congestion and delay. The simulation result shows that the proposed method has better performance in congestion control and packet loss ratio than the other existing methods of TCP-based method, UDP-based method and VBM-based method. The proposed method showed improvement of 10% in congestion control ratio and 8% in packet loss ratio compared with VBM-based method which is one of the best method.