• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.4B
• /
• pp.338-344
• /
• 2002

This paper proposes a transient (predictive) connection admission control (CAC) scheme using the transient quality of service (QoS) measure for CDMA cellular systems with bursts On-Off sources. We need an approximate and bounded approach for real-time CAC applications. We derive the transient outage probability as the QoS measure using the Chernoff bound and the refuted large deviation approximation. Numerical results show that the predictive CAC is a promising approach for the multicell CDMA systems.

• Journal of KIISE:Information Networking
• /
• v.34 no.5
• /
• pp.396-404
• /
• 2007

In this paper, an Ad-hoc Routing Protocol which works in wireless Ad-hoc communication networks with multiple radios and multiple channels, and controls call admission based on bandwidth measurement is proposed. Unlike the conventional Ad-hoc node with a single radio using a single channel, an Ad-hoc node of the protocol proposed, MCQosR(Multiple Channel Quality of Service Routing), has multiple radios and uses multiple channels, which makes full duplex transmission between wireless Ad-hoc nodes, and reduces the intra interference on a route. Also, a fixed channel only for reception at each node enables the measurement of the available bandwidth, which is used to control the call admission for QoS provision. The performance of MCQosR is verified by simulation.

• Proceedings of the KAIS Fall Conference
• /
• 2007.05a
• /
• pp.212-215
• /
• 2007

BcN은 유 ${\cdot}$ 무선에 관계없이 일정한 데이터 전송속도를 구현하는 것을 목표로 하고 있어 개인들이 하나의 단말기로 자유롭게 네트워크에 접속할 수 있는 "u-life(유비쿼터스 시대)" 진입이 한층 가속화될 전망이다. 본 논문에서는 ITD, ETSI, IETF에서의 QoS 정의를 살펴보고 각각을 비교하였으며, 각 표준화 기관에서의 QoS 파라미터를 근거로 BcN에서의 서비스 품질 및 네트워크 파라미터들을 정립하였다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.04d
• /
• pp.493-495
• /
• 2003

유선 네트워크에서의 토큰 패싱 LAN 접근 제어 방식을 무선 네트워크에 적용하면 네트워크의 높은 부하 상황에서도 안정된 성능을 보인다. 본 논문에서는 실시간 트래픽 서비스와 비실시간 트래픽 서비스가 공존하는 인터넷에서 서비스의 질을 지원하는 무선 토큰링 프로토롤을 제안하였다 제안된 프로토콜 메커니즘에서는 실시간 트래픽 서비스 노드에겐 비실시간 트래픽 서비스 노드보다 토큰 수신을 우선적으로서 부여함으로 빠른 전송을 지원하며, 기존의 토큰 전송 방식에 QoS를 지원하는 장점을 가진다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.7
• /
• pp.2513-2530
• /
• 2021

With the fast development of information and communication technologies, video streaming services and applications are increasing rapidly. However, the network condition is volatile. In order to provide users with better quality of service, it is necessary to develop an accurate and low-complexity model for Quality of Experience (QoE) prediction of time-varying video. Memory effects refer to the psychological influence factor of historical experience, which can be taken into account to improve the accuracy of QoE evaluation. In this paper, we design subjective experiments to explore the impact of Short-Term Memory (STM) on QoE. The experimental results show that the user's real-time QoE is influenced by the duration of previous viewing experience and the expectations generated by STM. Furthermore, we propose analytical models to determine the relationship between intrinsic video quality, expectation and real-time QoE. The proposed models have better performance for real-time QoE prediction when the video is transmitted in a fluctuate network. The models are capable of providing more accurate guidance for improving the quality of video streaming services.

• Journal of Internet Computing and Services
• /
• v.22 no.6
• /
• pp.1-8
• /
• 2021

With the rapid growth of intelligent devices and communication technologies, 5G network environment has become more heterogeneous and complex in terms of service management and orchestration. 5G architecture requires supportive technologies to handle the existing challenges for improving the Quality of Service (QoS) and the Quality of Experience (QoE) performances. Among many challenges, traffic steering is one of the key elements which requires critically developing an optimal solution for smart guidance, control, and reliable system. Mobile edge computing (MEC), software-defined networking (SDN), network functions virtualization (NFV), and deep learning (DL) play essential roles to complementary develop a flexible computation and extensible flow rules management in this potential aspect. In this proposed system, an accurate flow recommendation, a centralized control, and a reliable distributed connectivity based on the inspection of packet condition are provided. With the system deployment, the packet is classified separately and recommended to request from the optimal destination with matched preferences and conditions. To evaluate the proposed scheme outperformance, a network simulator software was used to conduct and capture the end-to-end QoS performance metrics. SDN flow rules installation was experimented to illustrate the post control function corresponding to DL-based output. The intelligent steering for network communication traffic is cooperatively configured in SDN controller and NFV-orchestrator to lead a variety of beneficial factors for improving massive real-time Internet of Things (IoT) performance.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.36S no.8
• /
• pp.30-38
• /
• 1999

On providing MPEG-2 video service through the ATM network, it is necessary for network provider to have the ATM QoS objectives in order to guarantee quality of service required by end users at the application layer. In this paper, the degradation of QoS caused by cell losses at application layer is assessed quantitatively by GIQ model considering AAL layer and is evaluated qualitatively by MOS from the viewpoint of the end users in order to analyze the relation between CLR and QoS of MPEG-2 video. From the simulation and empirical results, we know that CLR and $GIQ_{mean}$ for guaranteeing QoS of MOS grade 5(Excellent) are $CLR{\le}4{\times}10^7$ & $GIQ_{mean}{\ge}99.4%$ and those for guaranteeing QoS of MOS grade 4(Good) are $CLR{\le}2{\times}10^6$ & $GIQ_{mean}{\ge}99.705%$.

• Journal of KIISE:Software and Applications
• /
• v.37 no.5
• /
• pp.341-353
• /
• 2010

Mobile Internet Device (MID) allows users to flexibly use various forms of wireless internet such as Wi-Fi, GSM, CDMA, and 3G. Using such Internet, MID users can utilize application services. MID usage is expected to grow due to the benefits of portability, Internet accessibility, and other convenience. However, it has resource constraints such as limited CPU power, small memory size, limited battery life, and small screen size. Consequently, MIDs are not capable to hold large-sized complex applications and to process a large amount of data in memory. An effective solution to remedy these limitations is to develop cloud services for the required application functionality, to deploy them on the server side, and to let MID users access the services through internet. A major concern on running cloud services for MIDs is the potential problems with low Quality of Service (QoS) due to the characteristics of MIDs. Even measuring the QoS of such services is more technically challenging than conventional quality measurements. In this paper, we first identify the characteristics of MIDs and cloud services for MIDs. Based on these observations, we derive a number of quality attributes and their metrics for measuring QoS of mobile services. A case study of applying the proposed quality model is presented to show its effectiveness and applicability.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.1 no.2
• /
• pp.120-126
• /
• 2006

In this paper, we propose for improving QoS in hospital wireless network using Cellular-IP/PRC(Paging Route Cache) with Paging Cache and Route Cache in Cellular-IP. Although the Cellular-IP/PRC technology is devised for mobile internet communication, it has its vulnerability in frequent handoff environment. This handoff state machine using differentiated handoff improves quality of services in Cellular-IP/PRC. Suggested algorithm shows better performance than existing technology in wireless mobile internet communication environment. When speech quality is secured considering increment of interference to receive in case of suppose that proposed acceptance method grooves base radio station capacity of transfer node is plenty, and most of contiguity cell transfer node was accepted at groove base radio station with a blow, groove base radio station new trench lake acceptance method based on transmission of a message electric power estimate of transfer node be. Do it so that may apply composing PC(Paging Cache) and RC(Routing Cache) that was used to manage paging and router in radio Internet network in integral management and all nodes as one PRC(Paging Router Cache), and add hand off state machine in transfer node so that can manage hand off of transfer node and Roaming state efficiently, and studies so that achieve connection function at node. Analyze benevolent person who influence on telephone traffic in system environment and forecasts each link currency rank and imbalance degree, forecast most close and important lake interception probability and lake falling off probability, GoS(Grade of Service), efficiency of cell capacity in QoS because applies algorithm proposing based on algorithm use gun send-receive electric power that judge by looking downward link whether currency book was limited and accepts or intercept lake and handles and displays QoS performance improvement.

• Information and Communications Magazine
• /
• v.21 no.8
• /
• pp.107-121
• /
• 2004

광대역 통합망(BcN: Broadband convergence Networks)이란 통신$.$방송$.$인터넷이 융합된 품질 보장형 광대역 멀티미디어 서비스를 언제 어디서나 끊임없이 안전하게 이용할 수 있는 차세대 통합네트워크를 말한다. 이를 위하여 BcN 전달망은 서비스 품질(QoS: Quality of Service) 보장, 고도의 통신망 관리 기능과 보안(Security) 기능, IPv6 주소체계의 수용을 통하여 다양한 서비스를 쉽게 창출할 수 있는 개방형 망구조(Open API)를 도입한 통신망으로 유선ㆍ무선ㆍ방송 등의 다양한 가입자망의 특성을 통합하여 수용해야 하며, 표준 인터페이스를 통해 다양한 응용서비스의 개발 및 이용 환경을 제공할 수 있어야 한다.(중략)