• Convergence Security Journal
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• v.11 no.1
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• pp.3-10
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• 2011

This paper proposes DPA(Dynamic Priority Assignment) MAC protocol to improve the traffic QoS on the HFC-CATV(Hybrid Fiber Coax CAble TeleVision) network. In results, DPA MAC protocol is the best performance compare with to IEEE 802.14a MAC in mean request delay, mean access delay. Also, the paper prove a reliability of proposed protocol through comparison between performance analysis and simulation result of DAP MAC protocol.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.145-147
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• 2001

최근 무선 이동통신 네트워크 분야의 큰 변화 중에 하나는 무선 이동통신 네트워크와 IP기반의 인터넷 네트워크 기술의 결합이라고 할 수 있다. 그러나 문선 이동통신 네트워크 환경에서는 제한된 네트워크 대역폭과 모바일 호스트(Mobile Host)의 잦은 이동성에 기인한 핸드오프(Hand-Off)로 인하여 다양한 종류의 트래픽(Traffic)에 대한 QoS(Quality of Service)를 보장하기가 용이하지 않다. 3G 네트워크 환경에서는 기존의 서킷 기반이 아닌 패킷 기반의 네트워크 구조로 진화하고 있으며 이동통신 네트워크내에서의 다양한 멀티미디어 트래픽 요구와 함께 이런 멀티미디어 지원을 위한 3G 네트워크안의 QoS 보장이 이루어져야 한다. 본 논문에서는 3세대 이동 통신인 UMTS 네트워크를 기반으로 다양한 멀티미디어 데이터를 위하여 Core네트워크에서의 자원예약을 위하여 내부의 QoS 메커니즘을 관리하여 개선된 RSVP 프로토콜을 제안한다. 또한 그로 인해 발생하는 Signaling 오버헤드를 줄이기 위한 Unified-msg object와 MH(Mobile Host)의 Handoff 지원을 제안한다.

• Journal of the Korea Computer Industry Society
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• v.3 no.8
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• pp.1027-1038
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• 2002

Multimedia data services have been widely developed with the recent progression of the Internet technology. Multimedia services, especially, must guarantee Quality of Service with restricted environment resources. The abrupt increase of transmission quanta, so called burst, and the number of client that access multimedia server, with limited network bandwidth will demage the quality of service and the utilization of network resource. Smoothing techniques can reduce the burst of a variable bit rate stream by transmitting data at a series of fixed rates. In this paper, we present a new smoothing algorithm using MPEG's characteristics in transmitting stored video data with VBR. The smoothing algorithm we present will be verified with assorted existing techniques in diverse environments.

• IEMEK Journal of Embedded Systems and Applications
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• v.3 no.4
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• pp.198-206
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• 2008

Internet protocol television (IPTV), one of the most emerging services, offers multimedia streaming services with security, reliability, and relevant quality of service (QoS)/quality of experience (QoE). It provides added values to all the involving players and also brings technical and business challenges to them. For IPTV services, we expect to adopt the next generation network (NGN) environment for high quality and the Web technologies for personalization to meet the customer's necessity. Web can provide an open, flexible, and agile platform. Therefore, in this paper, we propose personalized IPTV services based on Web-based open platform in NGN environment and present functional architecture for Web-based personalized IPTV services. Technical issues for deploying the proposed IPTV services using Web are also provided. The objective of this paper is to analyze the critical architectural issues for developing viable and feasible networking platform models for personalized IPTV services.

• Journal of Broadcast Engineering
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• v.6 no.3
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• pp.234-245
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• 2001

According to market needs of better quality of service (QoS) for realtime multimedia services over Internet, they haute been standardizing RSVP, Intserv, and DiffiServ. This paper combines the benefits of RSVP/IntServ with scalable video encoding. We Propose that more important bit stream is given more priority such that limited network resources are reserved for the stream Various prioritizing approaches are proposed and compared to normal approach by using Network Simulator. The calculated QoS parameters such as Packet loss rate are used to calculate degree of degradation in video quality.

• Journal of Korea Multimedia Society
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• v.16 no.3
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• pp.290-301
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• 2013

The hospital network requires the effective transmission of multimedia PCAS data for medical treatment. But the network traffic has happened frequently in consultation hours because of the limited resources of hospital network and high capacity of PACS data. This is major interruption for the medical treatment. This problem can be solved by the adaptive QoS. In this paper, we design the middleware based QoS architecture in hospital network for controlling the contribution system. Our virtual simulation verifies that our middleware assures QoS of the priority PACS data of audio and image compared with the conventional hospital network.

• ETRI Journal
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• v.38 no.3
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• pp.444-454
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• 2016

Voice service is very demanding in cognitive radio networks (CRNs). The available spectrum in a CRN for CR users varies owing to the presence of licensed users. On the other hand, voice packets are delay sensitive and can tolerate a limited amount of delay. This makes the support of voice traffic in a CRN a complicated task that can be achieved by devising necessary considerations regarding the various network functionalities. In this paper, the support of secondary voice users in a CRN is investigated. First, a novel packet scheduling scheme that can provide the required quality of service (QoS) to voice users is proposed. The proposed scheme utilizes the maximum packet transmission rate for secondary voice users by assigning each secondary user the channel with the best level of quality. Furthermore, an analytical framework developed for a performance analysis of the system, is described in which the effect of erroneous spectrum sensing on the performance of secondary voice users is also taken into account. The QoS parameters of secondary voice users, which were obtained analytically, are also detailed. The analytical results were verified through the simulation, and will provide helpful insight in supporting voice services in a CRN.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.7
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• pp.2257-2285
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• 2022

Cyber-physical systems (CPS) have been growing exponentially due to improved cloud-datacenter infrastructure-as-a-service (CDIaaS). Incremental expandability (scalability), Quality of Service (QoS) performance, and reliability are currently the automation focus on healthy Tier 4 CDIaaS. However, stable QoS is yet to be fully addressed in Cyber-physical data centers (CP-DCS). Also, balanced agility and flexibility for the application workloads need urgent attention. There is a need for a resilient and fault-tolerance scheme in terms of CPS routing service including Pod cluster reliability analytics that meets QoS requirements. Motivated by these concerns, our contributions are fourfold. First, a Distributed Non-Recursive Cloud Model (DNRCM) is proposed to support cyber-physical workloads for remote lab activities. Second, an efficient QoS stability model with Routh-Hurwitz criteria is established. Third, an evaluation of the CDIaaS DCN topology is validated for handling large-scale, traffic workloads. Network Function Virtualization (NFV) with Floodlight SDN controllers was adopted for the implementation of DNRCM with embedded rule-base in Open vSwitch engines. Fourth, QoS evaluation is carried out experimentally. Considering the non-recursive queuing delays with SDN isolation (logical), a lower queuing delay (19.65%) is observed. Without logical isolation, the average queuing delay is 80.34%. Without logical resource isolation, the fault tolerance yields 33.55%, while with logical isolation, it yields 66.44%. In terms of throughput, DNRCM, recursive BCube, and DCell offered 38.30%, 36.37%, and 25.53% respectively. Similarly, the DNRCM had an improved incremental scalability profile of 40.00%, while BCube and Recursive DCell had 33.33%, and 26.67% respectively. In terms of service availability, the DNRCM offered 52.10% compared with recursive BCube and DCell which yielded 34.72% and 13.18% respectively. The average delays obtained for DNRCM, recursive BCube, and DCell are 32.81%, 33.44%, and 33.75% respectively. Finally, workload utilization for DNRCM, recursive BCube, and DCell yielded 50.28%, 27.93%, and 21.79% respectively.

• Journal of Advanced Navigation Technology
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• v.14 no.6
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• pp.865-873
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• 2010

In this paper, a novel schedulability criteria is developed to provide handover calls with Quality of Service (QoS) guarantees in terms of both minimum available bandwidth, maximum tolerated packet delay, and other additive QoS constraints as required by the real-time mobile traffic. This requires prediction of the handover time using mobility trends on the mobile station, which is used as input to this work. After the handover time and the QoS are negotiated, the destination base station makes attempts to give priority to handover calls over new calls, and pre-reserves resources that will have more chance of being available during the actual handover.

• Journal of Internet Computing and Services
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• v.9 no.3
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• pp.103-117
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• 2008

General customer uses internet, SMS(Short Message Service), ATM(Automated Teller Machine), DM(Direct Mail), and telephony services, etc, for service of big businesses and small and medium enterprises, securities, financial institutions, bank. In particular, the case of Fire insurance & Securities, financial institutions, banks must meet Real-Time constrain control through QoS(Quality of Service) ensure. In this paper, we design and implement a system model about Fault-Tolerance IVR(Interactive Voice Response) of Multi Channel Service based on CRM(Customer Relationship Management) environment for the first inbound position of customer. The proposed model can be widely used in Large-scale Customer Response service.