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针对异构无线网络多网协同的特点,从分析多个无线网络共存的资源管理优化体制构建思想出发,建立了新的异构无线网络资源统一管理优化模型,实现了协同信息的控制和管理,同时保证了异构数据呼叫业务的服务质量,解决了多网间资源管理优化问题。首先,该模型在对呼叫服务请求做优化决策时,不仅考虑了本网络服务域的可用资源、服务请求的速率以及本系统的长期收益,同时也考虑了其他网络服务域的整体长期收益;其次,通过对所提出的基于异构无线网络多网资源优化管理模型的性能进行理论分析,得到其重要服务质量参数——新呼叫阻塞率;最后,通过仿真比较可以看出,通过该模型获得的优化决策策略能充分利用异构无线网络中各个网络域的资源,不仅提高了资源的利用率,而且在提高网络整体长期收益的同时,也保证了移动服务的服务质量。与资源完全共享算法相比,本方法降低了新呼叫阻塞率。理论分析和实验证明了异构无线网络资源域间资源优化管理方法的有效性、适应性。 相似文献
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Quality of service provisioning for distributed data center inter-connectivity enabled by network virtualization 总被引:1,自引:0,他引:1
Thomas VoithAuthor Vitae 《Future Generation Computer Systems》2012,28(3):554-562
Today’s service platform or Cloud service models, such as Infrastructure-as-a-Service (IaaS), enable customers to deploy and execute applications on an on-demand available infrastructure. Such platforms reduce operational expenses for the service provider and lower the entry barrier for small and medium enterprises. However, current commercial solutions do not provide sufficient quality of service (QoS) guarantees for some applications. For example, they do not support various interactive real-time applications.In this paper, we introduce a way overcome these current Cloud service limitations. We show how to provide and guarantee quality of service requirements for resource networks within an IaaS framework.Our work has focused on methods for network resource management and flow control as well as QoS models. We have developed a framework that enables QoS support for real-time services executing within an IaaS environment. 相似文献
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网络与终端协同选择及切换机制的研究 总被引:1,自引:1,他引:0
提出了一种智能切换机制,用于实现在异构网络中网络与终端的协同选择及切换功能。随着各种业务和应用的发展,异构网络融合是信息和通信技术的必然趋势。根据多接入、多终端等应用环境的要求,采用AHP与URA等多属性决策理论,为用户选择最佳的目标网络和目标终端,并提出相应的智能切换信令流程,包括网络切换、终端切换、网络与终端联合切换方式,最终构建以用户为中心的多终端智能空间,实现个人移动性管理。仿真表明,该智能切换机制可以有效地实现网络和终端的协同选择,并可以保证在异构网络切换QoS性能,为现代服务业的业务及应用的发展提供可靠的理论依据。 相似文献
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通信技术的发展,使多种接入技术并存的异构网络成为未来通信网络的发展趋势,随着用户业务QoS需求的提高和传输带宽的增加,现有的网络选择算法已经不能满足用户高质量的通信需求。针对异构无线网络频谱资源日益紧缺的问题,提出了由用户端和网络端共同参与的两级动态网络选择方案。该方案包括灰度关联分析法和二分图联合优化匹配算法,通过用户端和网络端的共同决策,算法在有效满足移动用户业务服务质量需求的前提下,优化了系统吞吐量,均衡了网络负载。仿真实验表明,相对传统算法,该方案极大地提高了异构网络频谱资源利用率并降低了用户在无线网络间的切换概率,实现了用户需求和网络资源的合理配置。 相似文献
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Ethernet passive optical network (EPON) preserves the merits of traditional Ethernet network while reducing complexities and improving quality of service (QoS). In this paper, a traffic-class burst-polling based delta dynamic bandwidth allocation (TCBP-DDBA) scheme is presented to provide better QoS to expedited forwarding packet and maximize channel utilization service to assure forwarding and best effort packets. The network resources are efficiently utilized and adaptively allocated to the three traffic classes by guaranteeing the requested QoS. Simulation results using OPNET show that the TCBP-DDBA scheme performs well in comparison to the conventional allocation scheme for a set of given parameters such as: packet delay, queue size, packet delay variation and channel utilization. This work considers system-wide DBA development in contrast to unit-based approach. It is concluded that the algorithm can be used for many types of EPON-based practical distributed networks. 相似文献
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无线通信网络的发展趋势之一是将各种不同无线接入技术进行融合。多接入选择作为无线资源管理中的关键技术是目前异构网融合的研究热点之一。从用户的利益出发,充分考虑预接入网络的费用、QoS和稳定性;假定不同的网络运营商之间是彼此竞争的,即没有达成统一的协议,提出了一种结合目标代价函数与层次分析法的动态多接入选择算法。通过对影响因素进行分析和二次判断,建立了网络选择决策模型,仿真结果验证了该算法的正确性与有效性。 相似文献
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A novel prediction technique to improve quality of service (QoS) for heterogeneous data traffic 总被引:2,自引:1,他引:1
The present and future high-speed networks are expected to support wide variety real-time applications. However, the current
Internet architecture offers mainly best-effort service. It means that the network will do its best to deliver the data at
the destination without any guarantee. But the future integrated services networks will require guarantee for transferring
heterogeneous data. There are many parameters involved in improving the Quality of Service (QoS). QoS is a set of service
requirements to be met by the network while transporting a flow. In this paper, we consider four primary parameters are such
as reliability, delay, jitter, bandwidth which together determine the QoS. The requirements of the above parameters will vary
from one application to another application. Applications like file transfer, remote login, etc., will require high reliability.
But, applications like audio, video, etc., will require low reliability, because they can tolerate errors. The objectives
of this paper are to propose a novel technique to predict reason(s) for deterioration in the QoS and to identify the algorithm(s)/mechanism(s)
responsible for the deterioration. We are sure that this paper will give better results to improve the QoS and to improve
the performance of the network. 相似文献
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Mohsin Iftikhar Bjorn Landfeldt Sherali Zeadally Albert Zomaya 《Pervasive and Mobile Computing》2011,7(5):525-544
We are currently witnessing a growing interest of network operators to migrate their existing 2G/3G networks to 4G technologies such as long-term evolution (LTE) to enhance the user experience and service opportunities in terms of providing multi-megabit bandwidth, more efficient use of radio networks, latency reduction, and improved mobility. Along with this, there is a strong deployment of packet data networks such as those based on IEEE 802.11 and 802.16 standards. Mobile devices are having increased capabilities to access many of these wireless networks types at the same time. Reinforcing quality of service (QoS) in 4G wireless networks will be a major challenge because of varying bit rates, channel characteristics, bandwidth allocation and global roaming support among heterogeneous wireless networks. As a mobile user moves across access networks, to the issue of mapping resource reservations between different networks to maintain QoS behavior becomes crucial. To support global roaming and interoperability across heterogeneous wireless networks, it is important for wireless network operators to negotiate service level agreement (SLA) contracts relevant to the QoS requirements. Wireless IP traffic modeling (in terms of providing assured QoS) is still immature because the majority of the existing work is merely based on the characterization of wireless IP traffic without investigating the behavior of queueing systems for such traffic. To overcome such limitations, we investigate SLA parameter negotiation among heterogeneous wireless network operators by focusing on traffic engineering and QoS together for 4G wireless networks. We present a novel mechanism that achieves service continuity through SLA parameter negotiation by using a translation matrix, which maps QoS parameters between different access networks. The SLA matrix composition is modeled analytically based on the G/M/1 queueing system. We evaluate the model using two different scheduling schemes and we derive closed form expressions for different QoS parameters for performance metrics such as packet delay and packet loss rate. We also develop a discrete event simulator and conduct a series of simulation experiments in order to understand the QoS behavior of corresponding traffic classes. 相似文献
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基于QoS的网格资源管理 总被引:15,自引:0,他引:15
资源管理是网格计算研究领域中的一项重要研究点,目前的研究工作大多致力于解决异构性问题,对于在交付无缝QoS(quality of service)前提下提高资源分配性能方面还缺乏深入的研究.而且,目前对网格QoS的研究集中于将多媒体网络QoS的相关成果融入网格体系架构中以提供对网格QoS的支持,而缺少对网格QoS的特性进行系统化的研究与归纳.为此,提出了网格QoS的层次结构模型,并对其中承上启下的虚拟组织层QoS参数进行了新的分类和测量;然后,利用SNAP(service negotiation and acquisition protocol)协议对基于网格QoS层次结构模型的网格QoS参数的映射转换过程进行了分析;最后,设计了网格资源管理仿真系统,并运用相关的网格QoS的研究改进了现有的Min-Min算法.仿真实验结果表明,基于QoS的网格资源管理可以在满足用户QoS需求下,有效地提高网格资源的利用率和服务请求的成功率. 相似文献
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Multimedia applications in wireless communication have been increased in recent years. A variety of wireless access technologies is introduced for various needs. The abundant increase in mobile computing devices and different networking systems leads to the support of user’s mobility on heterogeneous network. In general, the roaming users migrate between two different wireless technologies and their service must be supported by vertical handover (HO). Since the roaming users expect a rapid handover experience while switching from one wireless network to another, the handover operation must be enhanced by the networks. Various wireless technologies such as wireless LAN, Worldwide Interoperability for Microwave Access (WiMAX), and the 3G Partnership Project (3GPP) are interlaced to support many wireless services in rural, urban, and global scenarios. Moreover, quality of service (QoS) has become more significant in many applications where wireless network resources are utilized. In this paper, a handover management scheme is proposed for QoS enhancement in roaming users between WiMAX and WLAN by subscribers of networks belonging to the 3GPP standards. The proposed algorithms genetic queuing, proportionally fair queuing, and WiMAX aware load balancing are analyzed in the scheduling process during handover. The simulation is implemented using NS–2 and the experimental results are obtained for the proposed algorithms and compared with the standard scheme. 相似文献
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User-perceived quality of service in wireless data networks 总被引:1,自引:0,他引:1
Anthony J. Saliba Michael A. Beresford Milosh Ivanovich Paul Fitzpatrick 《Personal and Ubiquitous Computing》2005,9(6):413-422
For so long, the term quality of service (QoS) has been a pursuit area for network engineers trying to dimension wireless
networks to run in the most efficient way possible. Of late, there has been a trend reversal, looking at the user perceptions
of the network performance to decide where dimensioning can have the greatest impact. This paper demonstrates the importance
of defining the concept of user-perceived QoS and linking this to specific wireless data network parameters for some anticipated
valuable applications. It has been shown that a quantitative rating can be obtained for a variety of important factors in
the assessment of service quality, and mapped to specific values of multiple network parameters. We found QoS to be application-specific,
where various applications require different levels of network performance to satisfy users. The role of physical location
was also examined, investigating the influence of being indoors versus outdoors on the user perception of QoS. 相似文献
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The high-speed transfer rate and various services of the wired network have been combined with the convenience and mobility
of wireless networks. This era of combined wire/wireless is being disseminated by new technology that creates new service
applications and brings changes to both users and service providers. Network integration is a very important in this wire/wireless
service, it is integrated by the convergence between heterogeneous networks and the integration of transmission technologies
across networks. In this situation, existing security and communication technologies are difficult to apply due to the need
to integrate with heterogeneous networks. Network security has many vulnerabilities. In existing homogeneous networks, user
authentication and key management between heterogeneous networks are needed to be adapted to new technology. The establishment
of security technologies to heterogeneous devices is also crucial between homogeneous networks. In this paper, we propose
secure, efficient key management in a heterogeneous network environment. Therefore, it provides secure communication between
heterogeneous network devices. 相似文献
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针对异构无线网络中的信任评估问题,提出了一种基于用户QoS感知的信任管理模型。该模型基于异构网络中业务交互及由此产生的用户QoS感知,刻画节点间的信任关系与信任度;并针对QoS感知的主观性和网络欺骗行为,给出了相应的信任策略。理论分析和仿真结果表明:该模型不仅能够有效地完成异构网络环境下的节点信任评估,并能抵御虚假欺骗、振荡服务等恶意行为。 相似文献