关于分组业务带宽预留比例的分析

在卫星通信系统中,支持分组业务是发展趋势,而提供分组业务要求合理地规划网络的接口传输带宽,规划一般都根据用户的平均带宽需求来进行,并且做出一定比例的带宽预留.本文针对泊松业务源,从概率分析的角度来解释业务总量超过分配带宽的概率与带宽预留比例之间的关系,为如何得到适当的带宽预留比例提供了理论参考.     

城域以太网业务

以太网业务是通过标准的、已经得到广泛认同的以太网接口来提供的.以太网业务因为具有容易使用、价格便宜以及灵活的带宽可扩展性等特点得到了业界的广泛关注.现在有很多的业务供应商都在提供以太网业务,一些供应商已经把以太网业务扩展到了城域甚至是广域的范围内.对城域以太网业务产生的背景和城域以太网业务的定义、框架结构、业务类别以及业务属性等进行了论述,并给出了一些应用实例.     

一种基于HFC的DTV和IP业务动态带宽分配机制

为了实时充分地利用数字电视业务下行传输中的剩余带宽来尽力而为地传输IP业务,探讨了有线电视网络下行传输中DTV和IP业务动态带宽分配的问题,提出了一种基于业务级别和视频质量评估系统的带宽分配算法,同时给出了相关的结构图和公式.     

EPON中支持多业务接入的动态带宽分配算法研究

以太网无源光网络(EPON)被视为下一代宽带接入网络(最后一公里问题)的最有吸引力的解决方案.EPON的一个主要特征是终端用户间共享上行信道,使用媒介接入控制方法来为不同流量类型提供多种服务.根据对已有的EPON上行带宽分配方案进行研究分析,并结合目前用户的多业务接入实际情况,提出了一种全面多业务接入的动态带宽分配的算法.     

基于多业务预测的EPON动态带宽分配算法

针对EPON系统中上行链路的时分复用机制,提出了一种基于多业务预测的动态带宽分配算法.该算法根据各个优先级业务的实时变化,通过一定的预测机制,实现动态分配带宽.相对其它算法,该算法能在保障高优先级业务优先的同时,降低数据时延.     

增强TD-SCDMA上行能力提升移动互联体验

增强TD-SCDMA网络的上行能力,可在有限的无线带宽资源下最大限度地提升数据业务的业务质量和业务带宽,提升网络竞争力。3G网络相对于2G无线传输速率高很多,微博、手机上网等迅猛增长的数据业务要求3G网络的上下行都能提供良好支撑。目前TD-SCDMA的高速数据业务只由HSDPA和HSUPA来承载,但由于HSUPA终端的成熟度问题导致HSUPA功能仍没有规模商用,因此高速的数据业务下行可以使用HSDPA,但是上行只能使用R4的DCH信道承载。现有TD-SCDMA网络的小区时隙配置一般为2:4,因此上行带宽资源(DCH)非常容易受限。     

国际带宽市场及网通的策略

所谓国际带宽业务。是指国际电信运营商以带宽形式提供给跨国用户的端到端的带宽联接服务,其实现有SDH及PDH透明电路、ATM、帧中继及各种形式的VPN等。本从国际带宽业务的发展历程出发,分析了国际带宽业务的历史、现状与未来发展趋势,力图让读对国际带宽市场有一个全面的了解和认识。     

SBS在ASON中的管理和实现

随着数据业务的爆炸式增长,如何在光网络中有效地利用宝贵的带宽资源已经成为研究人员所关注的焦点.基于时间分配带宽业务(SBS)是自动交换光网络(ASON)中的一种新型业务,可以被认为是传统的按需分配带宽(Bandwidth on Demand,BoD)业务的一种具体实现,SBS的出现既可以有效地为运营商节省宝贵的带宽资源,又可以降低用户的成本开销.文章从管理模型、实现方法以及社会价值等几个方面对SBS进行了详细的描述.     

信道带宽分配技术在卫星通信系统的应用

本文分析了基于业务预测的固定带宽分配模型和基于优先级的带宽分配模型在卫星通信系统的应用情况.     

IP网可用带宽快速检测方法SSP的研究与应用

在IP网中,可用带宽是最重要的网络资源,是网络传输性能的决定因素,可用带宽的实时检测具有重要的研究和现实意义.本文对当前典型的端到端的可用带宽测量工具Pathload进行了研究,分析了Pathload工具检测算法的优点以及不足,提出了一种快速而精确的带宽测量方法--SSP,通过它可以快速检测到端到端路径的可用带宽值,为有效利用网络资源、支持QoS服务和多媒体实时业务提供了保证.     

Interprovider differentiated service interconnection management models in the Internet bandwidth commodity markets

Due to the recent evolution of telecommunications infrastructure and the Internet as a commodity market for bandwidth, Internet Service Providers (ISPs) encounter new issues concerned with bandwidth management for the network interconnection. Bandwidth commodity exchange is considered a new B2B (Business-to-Business) electronic commerce application that brings new market opportunities to carriers and service providers for managing their bandwidth resources. This paper develops market-based bandwidth management optimization models for Differentiated Service (DiffServ) QoS (Quality of Service) networks using an implementation of the bandwidth management agent, BMP (Bandwidth Management Point). We use network economic models to formulate an optimization problem for the interconnection and resource allocation policy of the DiffServ network. We formulate and develop those economic models as optimization problems of LP, NLP, MILP and mixed integer nonlinear programming (MINLP), and discuss the pricing mechanisms and available solution approaches for the implementation of the BMP's resource optimization process. Different opportunity costs are estimated based on the results of a network simulation using traffic flow statistics measured from a recent Internet backbone. We then numerically simulate the behavior of backbone network ISPs to optimize their profits for various demand scenarios.     

一种保证EPON中DBA公平性的算法

动态带宽分配是以太网无源光网络(EPON)系统的一个重要研究领域,文章提出一种在EPON系统中保证动态带宽分配公平性的新型算法.该算法计算量适中, 同时兼顾了动态带宽分配的效率和公平性.文中通过推导给出了最优算法,并在模拟流量下进行了仿真,通过与已有算法的对比,证明其有很好的性能.     

Dynamic bandwidth allocation algorithm utilizing full band

A kind of Dynamic Full Bandwidth Utilized （DFBU） allocation algorithm is introduced. This algorithm allows a single link to use bandwidth far beyond its fair share bandwidth in a multi-service packet transporting system. Three important parameters as the bound on maximum and minimum bandwidth, the maximum packet delay and the minimum band width utilization are discussed and analyzed. Results of experiments show that the DFBU-algorithm is capable of making a single link in the system to use all the spare bandwidth （up to full-bandwidth） while the performance of fairness and QoS requirement is still guaranteed.     

网络智能化是承载“三网融合”重任的基石

从分析高清视频（电视）的3种不同传送方式对网络端到端带宽的需求入手,介绍了现阶段大带宽网络建设和有线网络改造在带宽方面的应用和管理模式,阐述了在网络架构中引入业务控制层的必要性。     

Pricing based adaptive scheduling method for bandwidth allocation

In this paper we present a packet scheduling method which guarantees bandwidth of the connection and optimizes revenue of the network service provider. A closed form formula for updating the adaptive weights of a packet scheduler is derived from a revenue-based optimization problem. The weight updating procedure is fast and independent on the assumption of the connections’ statistical behavior. The features of the algorithm are simulated and analyzed with and without a call admission control (CAC) mechanism. We also show in context with the CAC procedure a mechanism for guaranteeing a specified mean bandwidth for different service classes.     

A Novel Dynamic Bandwidth Assignment Algorithm for Multi-Services EPONs

1IntroductionIt seems that providing broadband services is thesaver of telecom industry. Long-haul and Metro corenetworks are capable of carrying broadband servicessince they have experienced a dramatic i mprovement inbandwidth capacity and efficiency with the advent oftechnologies such as Dense Wave length Division Multi-plexing (DWDM)[1 ~3]and other newtechnologies .Buta clear bottleneckexistsinthe“first mile”of access net-work[4]. Without eli minationthe bandwidth bottlenecksthat exis…     

一种适用于数控锁相环的动态带宽调整算法

为了加快数控锁相环的锁定速度,该文提出了一种适用于数控锁相环的动态带宽调整算法以加快锁定速度。仅当鉴相器鉴出的3次相位差均小于一定边界条件时,该算法才减少数控锁相环的带宽,并当鉴出的相位差超出一定边界条件时,该算法将立即增加带宽。为验证所提出的动态带宽调整算法,该文在MATLAB环境中建立了数控锁相环行为级模型。仿真结果表明,在相同参数情况下,采用该文提出的动态带宽调整算法可使锁定时间缩短至采用传统动态带宽调整技术锁定时间的28.6%~85.7%。最后,该文采用CSM 0.18 m 1P6M CMOS工艺实现数控锁相环并进行实测。实测结果表明,采用该文提出的动态带宽调整算法可快速消除相位差,并使得锁相环始终维持在相位锁定状态。该文提出的动态带宽调整算法,可以有效避免基于相位差调整锁相环频率的局限性,降低错误调整带宽的几率,继而加快锁定速度。     

QoS Routing in Wireless Mesh Networks

An H-hop interference model is proposed, where the transmission is successfully received if no other nodes that are within H hops from the receiver are transmitting on the same channel simultaneously. Based on this model. the interference-free property in the Time division multiple access Wireless mesh networks is analyzed. A heuristic algorithm with max-rain time slots reservation strategy is developed to get the maximum bandwidth of a given path. And it is used in the bandwidth guaranteed routing protocol to find a path for a connection with bidirectional bandwidth requirement. Extensive simulations show that our routing protocol decreases the blocking ratios significantly compared with the shortest path routing.     

Elliptical slot loaded partially segmented circular monopole antenna for super wideband application

This article inspects partially segmented circular monopole with elliptical slot for super wideband applications. Two significant characteristics of proposed antenna design are: (i) partially segmented circular monopole, notch loaded elliptical ground plane along with tapered microstrip line provides super wide bandwidth; (ii) elliptical slot in between the partially segmented circular monopole reduces the lower operating frequency (1.07 GHz–0.96 GHz), which in turn enhance the bandwidth dimension ratio (BDR). For verifying the simulated outcomes, antenna prototype is practically constructed and measured. The proposed antenna design attains frequency range from 0.96 GHz to 10.9 GHz (VSWR < 2) with bandwidth ratio of 11.35:1 and percentage bandwidth of 167.22%. Bandwidth dimension ratio of proposed radiator is 6975.22. Frequency as well as time domain analysis of proposed radiator approves its applicability for super wideband wireless applications.     

基于QoS的EPON系统动态带宽分配机制

通过阐述以太网无源光网络（EPON）系统信道传输数据方式以及动态带宽分配的工作原理,进一步研究了动态带宽分配算法（DBA）在EPON系统中的应用。提出一种基于服务质量（QoS）的EPON系统动态带宽分配机制,该机制根据不同业务的优先级和动态带宽分配算法,灵活地分配上行带宽,提高了带宽利用率,改善了服务质量。