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由RSVP在ATM捷径上实现综合业务IP的方案 总被引：2，自引：0，他引：2
本文介绍了由ATM捷径和RSVP实现IP与ATM融合的一种可行方案。该方案可以区分服务的方式提供综合业务IP。 相似文献
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Mazen G. Khair Burak Kantarci Hussein T. Mouftah 《International Journal of Communication Systems》2014,27(10):2007-2021
In this article, we propose a dynamic Internet Protocol (IP) address assignment architecture for heterogeneous wireless IP devices network. The IP device could be a sensor device, a laptop, a cell phone, or any wireless device using IP communications. The proposed architecture introduces security and service reliability to the consumer while reducing the operational expenditure for the service providers. According to the proposed scheme, each node maintains an IP address pool storing the current occupancy of each IP address. Each node advertises its database whenever the ratio of negative acknowledgments from the domain name server to the total number of requests at a given node exceeds a certain threshold. We evaluate our IP assignment scheme under two traffic intensity scenarios, namely the uniform traffic intensity and the heterogeneous traffic intensity. Performance evaluation is carried out with respect to blocking probability and average IP list utilization. We define three types of blocking probability for the user requests as follows: The real blocking, the unjustified acceptance, and the unjustified rejection. We observe that the proposed scheme outperforms the uniform assignment as long as the threshold is below 1.5% for the uniform intensity scenario and 1% for the heterogeneous scenario. Furthermore, this architecture considers the security aspect of the wireless network by allowing only registered devices to communicate with other registered devices. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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IP in the edge and ATM in the core are commonplace in today's internetworks. The IETF has proposed a new Quality of Service (QoS) mechanism namely Differentiated Services (DiffServ) for IP networks. On the other hand, QoS is an inherent feature in ATM. It is imperative that IP and ATM QoS interoperate efficiently to provide an end-to-end service guarantee. DiffServ provides a class of service named Assured Forwarding (AF) that does not exactly correlate to any of the service categories offered by ATM. AF is targeted towards a range of applications, such as real-time (rt) that do not require a constant bit rate service provided by Expedited Forwarding, and other non-real-time (nrt) applications that expect a service better than best effort. In this paper we propose the mapping of AF to the Variable Bit Rate (VBR) service category in ATM. VBR is suitable because it is available in the form of rt-VBR and nrt-VBR and could be translated appropriately based on the applications. The mapping is implemented and verified using the LBNL Network Simulator. The results of the experiments show that VBR is a better match for AF than any other service category in ATM. 相似文献
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Artur Ziviani Jos F. de Rezende Otto Carlos M. B. Duarte 《International Journal of Communication Systems》2002,15(9):799-813
The Differentiated Services architecture offers a scalable alternative to provide Quality of Service (QoS) to the new multimedia applications in the Internet. This paper aims at evaluating the delay and jitter experienced by voice traffic when handled by the Expedited Forwarding (EF) scheme. The analysis includes the effects of different packet scheduling mechanisms implementing EF and of the voice packet size. We also evaluate how efficiently each type of traffic uses an extra allocated bandwidth and the impact of traffic shaping. The results show that increasing the service rate share allocated to the EF aggregate does not significantly affect the competing best effort (BE) traffic. This holds as long as the BE traffic can use the bandwidth left unused by the EF traffic in idle periods. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Khaled Shuaib Abderrahmane Lakas Farag Sallabi 《International Journal of Communication Systems》2006,19(7):775-794
Real‐time traffic such as voice and video, when transported over the Internet, demand stringent quality of service (QoS) requirements. The current Internet as of today is still used as a best effort environment with no quality guarantees. An IP‐based Internet that supports different QoS requirements for different applications has been evolving for the past few years. Video streams are bursty in nature due to the instant variability of the video content being encoded. To help mitigate the transport of bursty video streams with minimal loss of information, rate‐adaptive shapers (RASs) are usually being used to reduce the burstiness and therefore help preserve the desired quality. When transporting video over a QoS IP network, each stream is classified under a specific traffic profile to which it must conform, to avoid packet loss and picture quality degradation. In this paper we study, evaluate and propose RASs for the transport of video over a QoS IP network. We utilize the encoding video parameters for choosing the appropriate configuration needed to support the real‐time transport of Variable Bit Rate (VBR) encoded video streams. The performance evaluation of the different RASs is based on the transport of MPEG‐4 video streams encoded as VBR. The performance is studied based on looking at the effect of various parameters associated with the RASs on the effectiveness of smoothing out the burstiness of video and minimizing the probability of packet loss. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Hamada Alshaer 《International Journal of Communication Systems》2014,27(11):2832-2850
Internet protocol (IP) traffic connections arrive dynamically at wavelength‐division multiplexing (WDM) network edges with low data rates compared with the wavelength capacity, availability, and quality‐of‐service (QoS) constraints. This paper introduces a scheme to be integrated into the control and management plane of IP/WDM networks to satisfy the availability and QoS required for IP traffic connections bundled onto a single wavelength (lightpath) in WDM networks protected by shared‐backup path protection (SBPP). This scheme consists of two main operations: (i) routing multi‐granular connections and traffic grooming policies, and (ii) providing appropriate shared protection on the basis of subscribers’ service‐level agreements in terms of data rate, availability, and blocking probability. Using the Markov chain process, a probabilistic approach is developed to conceive connection blocking probability models, which can quantify the blocking probability and service utilization of M:N and 1:N SBPP schemes. The proposed scheme and developed mathematical models have been evaluated in terms of bandwidth blocking ratio, availability satisfaction rate, network utilization, and connection blocking probability performance metrics. The obtained research results in this paper provide network operators an operational setting parameter, which controls the allocation of working and backup resources to dynamic IP traffic connections on the basis of their priority and data rate while satisfying their requirements in terms of bandwidth and availability. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Optical Burst Switching (OBS) has been proposed as a promising switching technology for the next generation of optical transport networks. In this paper, we address the issue of how to provide proportional differentiated services in OBS networks. Firstly, a Dynamic Wavelength Selection (DWS) scheme is introduced to provide proportional differentiated services in bufferless OBS networks by dynamically assigning more and longer periods of wavelengths to high priority classes. This scheme can also utilize wavelengths efficiently because the wavelengths are shared among different classes. Next, a Delayed Burst Assignment (DBA) scheme is introduced, by which bursts of the high priority class are given a higher probability for reserving wavelengths by scheduling the bursts of the low priority class with a delay to provide quality of service (QoS) in OBS networks. The integration of these two schemes provides proportional differentiated services and improves the burst loss performance by giving the burst head packet (BHP) two opportunities of scheduling its data burst (DB). 相似文献
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随着我国移动通信的迅猛发展 ,用户对于移动增值业务的需求越来越高。如何建立一个高效的移动增值业务服务支持系统 ,并保证移动增值业务的服务品质 ,是一个急需研究和解决的重要课题。本文针对这一问题 ,从系统体系结构的角度提出了一种多 Agent移动信息服务支持系统。该系统提供了可以高效地配置与管理信息类移动增值业务的系统解决方案 ,尤其适用于主动式高级信息服务类增值业务。这一系统结构适应性强、易扩展、易维护 ,并能够更好地支持对用户的个性化服务。该系统具有广泛的应用前景 ,对于未来 3G的增值业务具有一定的参考价值 相似文献
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本文阐述了IMS业务引擎的基本概念及研究进展,介绍了IMS典型业务引擎及彼此之间的关系,结合一种基于IMS业务引擎的组合类业务实例,分析了IMS业务引擎对IMS业务发展的助力作用,最后探讨了电信运营商发展IMS业务引擎应考虑的主要问题. 相似文献
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Jan A. Van Mieghem Piet Van Mieghem 《International Journal of Communication Systems》2002,15(5):429-452
We present an integrated approach to pricing and scheduling for services that are differentiated in terms of throughput, delay and loss specifications. The key building block to the model are quality value curves that specify a user's value of higher quality levels. From the analysis emerges a pricing rule that charges based on rate and quality grade, and a dynamic scheduling rule, called the Gcµ rule. The analysis also derives the economically optimal probabilistic quality of service (QoS) guarantee parameters. We compare our model to the deterministic approach of QoS guarantees using burstiness constraints and fair scheduling rules. The scheduling that arises from such a deterministic approach is the well‐known Generalized Processor Sharing (GPS). A comparative analysis inspires the fair Gcµ‐PS rule as the scheduling rule that combines the unique strengths of GPS and Gcµ. This Gcµ‐PS rule is proposed as a tailored scheduling solution for both the expedited forwarding class and the four assured forwarding classes in the IETF's differentiated services. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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基于区分服务的IP-UMTS视频传输QoS机制 总被引：1，自引：1，他引：1
为了满足在以IP作为骨干网协议,以通用移动通信系统(UMTS)作为接入网的异构网络环境中视频传输的服务质量要求.提出了基于区分服务的视频传输服务质量机制,给出了区分服务业务等级到视频数据帧和区分服务业务等级到UMTS业务类别的映射关系.使用仿真的实验环境对给定的服务质量机制进行了测试,实验结果表明该服务质量机制能有效地提高IP-UMTS异构网络中视频传输的服务质量. 相似文献
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Web与IMS分别是互联网业务与电信网业务的主流技术,这两类业务的融合是当前的研究热点。概述了Web与IMS业务融合的实质与场景,总结了业务融合的两种技术方案,即基于集成应用服务器的方案与基于ParlayX网关的方案,并从适用场景、Web服务支持、通信效率及可实现性等方面进行了分析比较。两种方案在适用场景和可实现性方面相当,但是第一种方案具有更高的通信效率,并且支持更多的Web服务模型。因此在通常的应用场合下,可优先考虑采用基于集成应用服务器的业务融合方案。 相似文献
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随着高流量4G计划的普及以及在线游戏,在线视频,即时消息等移动互联网应用的快速发展,4G网络负载变得越来越繁重.在网络资源不足的情况下,电信运营商必须为不同类型的用户和服务提供差异化的网络服务,以吸引和留住高价值用户,提高网络的竞争力.本文尝试以无线资源利用率为触点,联动核心网与无线侧能力,通过实施基于QoS (Qua... 相似文献
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Katsuhiro Koga Naonobu Okazaki Akira Watanabe Mi rang Park 《Electronics and Communications in Japan》2011,94(12):29-44
In recent years, DoS (Denial of Service) attacks and more powerful DDoS (Distributed DoS) attacks have posed security problems on the Internet. For countermeasure to these attacks, it is important to trace attackers and stop the attacks. However, since information about the attackers is “spoofed,” such attacks are difficult to trace. Therefore, a method of identifying attackers is required. Savage and colleagues proposed a method of tracing flooding attacks by using “marked” packets. This method, however, involves problems in gathering the attack packets through numerous hops. In this paper, we propose a method of resolving this problem by observing the features of the attack traffic and changing the “marking probability” in the routers. We implement algorithms of both our proposed method and the extended marking method to estimate their efficiency. The experimental results confirm the effectiveness of the proposed method. © 2011 Wiley Periodicals, Inc. Electron Comm Jpn, 94(12): 29–44, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/ecj.10346 相似文献
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Angelos Michalas Malamati Louta Paraskevi Fafali George Karetsos Vassilios Loumos 《International Journal of Communication Systems》2004,17(7):743-761
Supporting quality of service (QoS) over the Internet is a very important issue and many mechanisms have already been devised or are under way towards achieving this goal. One of the most important approaches is the so‐called Differentiated Services (DiffServ) architecture, which provides a scalable mechanism for QoS support in a TCP/IP network. The main concept underlying DiffServ is the aggregation of traffic flows at an ingress (or egress) point of a network and the marking of the IP packets of each traffic flow according to several classification criteria. Diffserv is classified under two taxonomies: the absolute and the relative. In absolute DiffServ architecture, an admission control scheme is utilized to provide QoS as absolute bounds of specific QoS parameters. The relative DiffServ model offers also QoS guarantees per class but in reference to the guarantees given to the other classes defined. In this paper, relative proportional delay differentiation is achieved based on class‐based queueing (CBQ) scheduler. Specifically, the service rates allocated to the classes of a CBQ scheduler are frequently adjusted in order to obtain relative delay spacing among them. The model presented can also be exploited in order to meet absolute delay constraints in conjunction with relative delay differentiation provision. Simulation experiments verify that our model can attain relative as well as absolute delay differentiation provided that the preconditions posed are satisfied. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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This paper presents an optimal proportional bandwidth allocation and data droppage scheme to provide differentiated services (DiffServ) for downlink pre‐orchestrated multimedia data in a single‐hop wireless network. The proposed resource allocation scheme finds the optimal bandwidth allocation and data drop rates under minimum quality‐of‐service (QoS) constraints. It combines the desirable attributes of relative DiffServ and absolute DiffServ approaches. In contrast to relative DiffServ approach, the proposed scheme guarantees the minimum amount of bandwidth provided to each user without dropping any data at the base‐station, when the network has sufficient resources. If the network does not have sufficient resources to provide minimum bandwidth guarantees to all users without dropping data, the proportional data dropper finds the optimal data drop rates within acceptable levels of QoS and thus avoids the inflexibility of absolute DiffServ approach. The optimal bandwidth allocation and data droppage problems are formulated as constrained nonlinear optimization problems and solved using efficient techniques. Simulations are performed to show that the proposed scheme exhibits the desirable features of absolute and relative DiffServ. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献