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1.
Dynamic resource allocation in ATM networks   总被引:2,自引:0,他引:2  
This article investigates resource allocation in ATM networks and emphasizes bandwidth allocation. Resource allocation methods are categorized, and static and dynamic allocation strategies are compared. Dynamic allocation uses actual traffic behavior, while static allocation uses only the reference traffic condition given a priori. Examples of dynamic allocation strategies are available bit rate flow control, dynamic connection admission control, and dynamic VP bandwidth control. Dynamic resource allocation is shown to be promising for situations where the a priori reference model is unclear  相似文献   

2.
A 10-cell, 10-channel line-of-sight (LOS) microcellular environment with Poisson arrivals and exponentially distributed holding times is stimulated. The performance of cellular systems for personal communications networks (PCNs) is evaluated. Call blocking, bumping, and dropping probabilities, as affected by fast fading, power control, and traffic load, for LOS, 900-MHz microcellular environments are discussed. It is established that DRA (dynamic resource allocation) using local information only does not result in a performance penalty. In fact, in the cases of interest, it performs significantly better than fixed channel allocation, increasing capacity by about 20%, or even as much as 60% with power control. It is shown that fast fading results in a limited increase, about 2-3 times the blocking probability, while the use of power control translates directly, and consistently, into a significant increase in traffic handling capacity  相似文献   

3.
Network resource management for enterprise wide multimedia services   总被引:2,自引:0,他引:2  
The support of broadband multimedia applications over an enterprise network poses a broad range of networking challenges for efficient resource management, intelligent switching, and access control for distributed information. We propose two server-based scheduling algorithms, with low computational complexity, to guarantee multimedia information synchronization at the destination, with minimum presentation delays and buffer requirements. We outline a communication framework, highlighting the issues and challenges faced by today's enterprise networks to support multimedia services. We describe the proposed connection establishment and resource allocation schemes in resource-constrained enterprise networks. The objective is to manage the limited resources of the network for maximum utilization. Towards this end we present a dynamic capacity allocation scheme to support connections for multiple users. Specifically, we show that the channel capacity allocation problem can be formulated as a quadratic programming problem. This allocation scheme is implemented at each intermediate switch to dynamically determine the capacity allocation. The effects of interswitch rate mismatch and network delay offset scheduling have also been incorporated in the management framework. In addition, we introduce the concept of route selection based on the requested network quality of service  相似文献   

4.
Power control in direct sequence code division multiple access (DS-CDMA) systems and power/rate allocation in multirate DS-CDMA based networks is an open and interesting research area which has attracted much attention. However, with a few exceptions, most researchers have emphasized centralized resource allocation algorithms for cellular systems where the base station keeps track of the requirements of the various users and is thus responsible for the management of network resources. Ad hoc wireless local area networks (WLANs), on the other hand, are generally configured as peer-to-peer networks with no centralized hub or controller. Thus resource allocation has to be conducted in a distributed fashion. We address the issue of distributed resource management for multirate DS-CDMA based multimedia WLANs by (1) presenting a distributed resource allocation protocol, known as distributed resource negotiation protocol (DRNP) that builds on the RTS/CTS bandwidth reservation mechanism provided by IEEE 802.111, and provides quality of service (QoS) guarantees through distributed control of resources in DS-CDMA based multimedia WLANs and (2) investigating the performance of various resource allocation schemes within the context of DRNP, in terms of network wide metrics such as overall throughput and blocking rates  相似文献   

5.
Differentiated services networks are fair in the way that different types of traffic can be associated to different network services, and so to different quality levels. However, fairness among flows sharing the same service, may, not be provided. Our goal is to study fairness between scalable multimedia sessions for assured DS services in a multicast network environment. To achieve this goal, we present a fairness mechanism called session-aware popularity-based resource allocation (SAPRA), which allocates resources to scalable. sessions based on their number of receivers. Simulation results in a scalable and multireceiver scenario show that SAPRA maximizes the utilization, of bandwidth and the number of receivers with high-quality reception  相似文献   

6.
Cloud download service, as a new application which downloads the requested content offline and reserves it in cloud storage until users retrieve it, has recently become a trend attracting millions of users in China. In the face of the dilemma between the growth of download requests and the limitation of storage resource, the cloud servers have to design an efficient resource allocation scheme to enhance the utilization of storage as well as to satisfy users' needs like a short download time. When a user's churn behavior is considered as a Markov chain process, it is found that a proper allocation of download speed can optimize the storage resource utilization. Accordingly, two dynamic resource allocation schemes including a speed switching (SS) scheme and a speed increasing (SI) scheme are proposed. Both theoretical analysis and simulation results prove that our schemes can effectively reduce the consumption of storage resource and keep the download time short enough for a good user experience.  相似文献   

7.
CDMA2000 1/spl times/EV-DV has been proposed as one of the global standards of third-generation (3G) networks, which adopts TDM/CDM and adaptive modulation and coding (AMC) techniques to enhance the data rate. The current CDMA2000 1/spl times/EV-DV standard specifies all possible combinations of system parameters, but there is no any further specification in the standard on how to dynamically change the system parameters to support the quality-of-service (QoS) requirements imposed by the upper-layer applications. In the meantime, one of the major deficiencies of previous research work done in this area is that they all are based on the channel models of physical layer such as Rayleigh model, which is unable to capture the link-layer QoS parameters such as queueing delay. Since the dynamic resource allocation usually resides in the data link layer, a wireless channel model at the link layer would be desirable to handle the QoS requirements. In this paper, we develop a dynamic resource allocation scheme using the effective capacity link model to support delay-bounded multimedia services in CDMA2000 1/spl times/EV-DV networks. Extensive simulations have been set up and the simulation results show that the proposed dynamic resource allocation scheme significantly improves the delay and throughput performance for all types of application traffic with various QoS requirements.  相似文献   

8.
Cloud computing is a key technology for online service providers. However, current online service systems experience performance degradation due to the heterogeneous and time-variant incoming of user requests. To address this kind of diversity, we propose a hierarchical approach for resource management in hybrid clouds, where local private clouds handle routine requests and a powerful third-party public cloud is responsible for the burst of sudden incoming requests. Our goal is to answer (1) from the online service provider’s perspective, how to decide the local private cloud resource allocation, and how to distribute the incoming requests to private and/or public clouds; and (2) from the public cloud provider’s perspective, how to decide the optimal prices for these public cloud resources so as to maximize its profit. We use a Stackelberg game model to capture the complex interactions between users, online service providers and public cloud providers, based on which we analyze the resource allocation in private clouds and pricing strategy in public cloud. Furthermore, we design efficient online algorithms to determine the public cloud provider’s and the online service provider’s optimal decisions. Simulation results validate the effectiveness and efficiency of our proposed approach.  相似文献   

9.
Both call admission control (CAC) and efficient scheduling are of great importance in next generation wireless networks, which are expected to handle various types of highly demanding multimedia users. In this paper, we present and evaluate a new mechanism which combines CAC with bandwidth allocation in a high-speed downlink time division multiple access (TDMA) wireless channel with errors; our mechanism incorporates predictions of the wireless channel condition in its decision making and our results show that, with the use of the feedback between the scheduler and the admission controller, system performance is significantly enhanced (in terms of voice-WAP-SMS-H.263 video QoS) compared to a scheme without prediction on the channel condition.  相似文献   

10.
Advances in wireless technology and availability of portable devices with networking capabilities have enabled ubiquitous Web accessibility. This has created the need to provide advance Internet services to mobile users without causing service failures due to connection migration or handoffs. However, scarcity of wireless resources restricts the provision of multimedia services in wireless networks. We address the issue of managing wireless resources to support Web-based multimedia document services including MPEG-4-based applications, in wireless networks with a high degree of user mobility. In particular, we formulate the resource management problem in wireless networks as an optimization problem with an objective function comprising different quality of presentation parameters.  相似文献   

11.
Modern wireless orthogonal frequency division multiple access (OFDMA) systems incorporate dynamic resource allocation (DRA), adaptive modulation and coding (AMC), and power control (PC) to exploit multiuser diversity and achieve higher system throughput. In the literature, only a few proposed algorithms deal with the contiguous DRA problem according to which a contiguous collection of resources can be allocated to each user. This paper formulates this high complexity problem, provides a suitable decision metric and a simple yet efficient solution. The proposed algorithm allocates in each step a contiguous collection of resources to the pending user that leads to the highest estimated correctly received number of bits. Simulation results show that, in this way, considerably improved performance can be achieved in terms of overall system throughput, spectral efficiency, and served traffic. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

12.
Liang  Yao-Jen 《Wireless Networks》2019,25(4):1605-1617

User mobility is a challenging issue in macro and femto cellular networks for the fifth-generation and newer mobile communications due to the time-varying interference and topology experienced. In this paper, we consider an OFDMA-based two-tier network with one macro cell and several femto cells, wherein each macro user and/or femto user can leave or enter its serving cell frequently, referred to as user mobility. A resource allocation problem with different rate requirements of mobile users is then formulated. Assuming well knowledge of the user locations and the channel state information, we propose a dynamic algorithm with static and dynamic parts for a better trade-of between computational complexity and system throughput. The static algorithm, named interference weighted cluster algorithm in this paper, is based on the graph theory to cluster the femtocells by minimizing the interference between clusters, while the dynamic algorithm is to deal with the user mobility by sharing the resource blocks under the constraints of rate requirements. Numerical results are demonstrated to show the effectiveness of the proposed dynamic resource allocation algorithm in terms of capacity, computational time, and outage probability.

  相似文献   

13.
密集家庭小区网络提高了网络容量,同时也严重增大了网络的能耗。为了提高家庭基站网络的能效,针对密集家庭小区场景,联合考虑家庭用户的异构服务、电路功率、网络的跨层干扰,提出了最大化家庭用户总能效的资源分配算法,利用Dinkelbach理论和拉格朗日对偶分解理论,求解了该优化问题的闭式解,并分析了算法复杂度。仿真结果表明,所提的资源分配算法具有更高的网络能效,比已有资源分配算法的能效提高了约20%。  相似文献   

14.
We propose to add a new dimension to existing wireless multimedia systems by enabling autonomous stations to dynamically compete for communication resources through adjustment of their internal strategies and sharing their private information. We focus on emerging spectrum agile wireless networks, where developing an efficient strategy for managing available communication resources is of high importance. The proposed dynamic resource management approach for wireless multimedia changes the passive way stations are currently adapting their joint source-channel coding strategies according to available wireless resources. Each wireless station can play the resource management game by adapting its multimedia transmission strategy depending on the experienced channel conditions and user requirements. The resource allocation game is coordinated by a network moderator, which deploys mechanism-based resource management to determine the amount of transmission time to be allocated to various users on different frequency bands such that certain global system metrics are optimized. Subsequently, the moderator charges the various users based on the amount of resources it has allocated to them, in order to discourage them from being dishonest about their resource requirements. We investigate and quantify both the users' and the system performance when different cross-layer strategies, and hence users' levels of smartness, are deployed by wireless stations. Our simulations show that mechanism-based resource management outperforms conventional techniques such as air-fair time and equal time resource allocation in terms of the obtained system utility. They also provide insights that can guide the design of emerging spectrum agile network protocols and applications  相似文献   

15.
This paper analyses the possibility of receiving high data rate multimedia services in the non-stationary urban mobile scenario using the digital video broadcast standard DVB-T2. The work focuses on the complex urban mobile environment and presents a comparison between the different configuration parameters and the data rates associated to different video services. The study is based on the experience operating an experimental DVB-T2 network in urban environments, where portable and vehicular reception scenarios have been tested. The results show the system performance and the feasible video quality. The paper explores the coverage for various video services, including HDTV and 3DTV options, and proposes some scenarios for the deployment of broadcasting networks transmitting multimedia services to mobile receivers.  相似文献   

16.
王圆春  肖东  林云 《电波科学学报》2022,22(5):802-809, 836
为更合理利用频谱资源以及更好地评估各类电磁环境,本文提出一种基于关联规则挖掘的频谱数据挖掘方案. 该方案首先基于一般挖掘流程获取频谱数据中的有用信息,包括异常信息、底噪信息、占用度信息和预定时间功率信息等;再将频谱信息作为关联分析对象,通过构建关联库,构建模糊集,基于模糊关联规则挖掘算法对频谱信息进行系统性的分析. 本文对传统的算子选择策略加以改进,使用大尺度参数改进模糊隶属函数. 通过实测数据集的验证分析,实验结果表明,频谱信息的强关联规则能反映各种信息之间隐含的关联性以及各种信息出现的频次;基于频谱信息的关联规则挖掘能有效地简化频谱挖掘工作,通过各种信息的关联性可以通过分析一部分频谱信息而得到另外的频谱信息. 频谱信息的关联规则可以用于进行电磁无线电环境的评估,选择合适的频谱信息该方案可以应用于各类电磁环境的评估.  相似文献   

17.
Hu  Jiangqi  Yang  Qinghai 《Wireless Networks》2019,25(6):3005-3018
Wireless Networks - In this paper, we investigate the dynamic energy-efficient resource allocation and analyze delay in newly emerging wireless powered communication network (WPCN). Considering the...  相似文献   

18.
崔高  戎蒙恬  刘涛 《信息技术》2011,(8):10-12,19
提出一种中继蜂窝网络中基于动态复用分割的无线资源分配方案。该方案在所设计的帧结构基础上,从时间域和频率域进行联合的资源分配。其基本思想是通过小区间的协作使频带资源可以最有效的复用来提高系统性能。仿真结果论证了该方案在小区容量方面可以获得较大的增益。  相似文献   

19.
Dynamic bandwidth allocation in DVB-T networks providing IP services   总被引:1,自引:0,他引:1  
The combination of high capacity, signal robustness, and worldwide acceptance have made digital terrestrial broadcasting (DVB-T) one of today's more promising technologies, while newly adopted standards support the integration of digital television programs and data services within a single multiplex, offered to both stationary and mobile end users. The paper addresses the issue of optimal bit rate allocation among DTV and IP services within the DVB-T multiplex, and demonstrates a novel configuration providing real-time sharing of the available bandwidth via an algorithm based on service hierarchy and perceptual quality assessment. The architecture and performance of a fully functional DVB-T testbed developed on this concept is also presented.  相似文献   

20.
This paper proposes novel resource sharing schemes for differentiated services (DiffServ) networks, to achieve both high resource utilization and quality of service (QoS) guarantee. Service level agreements (SLAs) are negotiated at network boundaries and supported by path-oriented resource mapping within the network. The recently proposed SLA management scheme based on virtual partitioning (Bouillet et al., 2002) allows overloaded SLAs to exploit the spare capacity of underloaded SLAs for efficient resource utilization, however, at the the cost of possible SLA violation of the underloaders. In the bandwidth borrowing scheme proposed here, the dedicated bandwidth for underloaded SLAs is determined and adaptively adjusted at network boundaries according to the actual traffic load and QoS policies; the available spare capacity is then properly distributed to related links for lending to others. On the other hand, the traffic flows admitted with borrowed bandwidth are tagged and may be preempted later when the original bandwidth owner needs to claim back the resources. Through a detailed implementation design and extensive computer simulation results we show that, by bandwidth borrowing, both SLA compliance and high resource utilization can be achieved in various load conditions, with some side benefits such as call-level service differentiation, small admission overhead, and convenience for policy-based management. In addition, we propose a distributed bandwidth pushing scheme that can dynamically adjust the spare bandwidth distribution over the network. Combining bandwidth pushing with bandwidth borrowing, the resource utilization can be further improved.  相似文献   

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