HSDPA系统中一种感知用户终端缓存状态的QoE保障调度算法

针对HSDPA系统中现有调度算法无法满足实时业务QoE的缺点,提出一种保障实时业务QoE的调度算法。该算法根据用户反馈的信道质量信息和在基站获取到的用户终端缓存状况信息。确定用户的优先级并据此调度优先级最高的用户,进而保证实时业务的吞吐量和QoE需求。仿真结果表明,与轮询调度算法、比例公平调度算法相比,提出的调度算法不仅能够保证实时业务的QoE需求,而且能满足非实时业务基本的吞吐量需求。     

基于模糊流感知的动态优先公平调度算法

为适应网络的动态性,提高调度公平性和资源效率,流感知优先公平调度机制需要动态的多业务区分转发。与链路负载状态相关的模糊流感知能够实现路径上的一致性业务区分,而基于模糊流感知的动态优先公平调度算法通过调整优先队列负载门限在流式流和弹性流之间实现转发优先权的动态交替,在链路轻载时实现不同流间的相对公平调度,在链路重载时则强调实时业务的绝对优先权以保证其时延要求。算法公平性分析和仿真计算显示提出算法的动态区分转发通过适度增加优先业务队长能够大幅度提高弹性流的接纳率,具有较高的链路平均吞吐量和资源效率。     

LTE系统上行链路调度算法研究

长期演进(Long Term Evolution,LTE)已经成为4G无线技术标准。目前,LTE分组调度的下行链路调度被大多数研究者研究,上行链路的研究相对较少。针对上行链路调度无法保证实时业务分组在延迟期限内传输,存在公平性较差、分组丢弃多的问题。因此,提出了一种新的上行链路调度算法。该算法根据实时业务的延迟约束条件建立目标整数线性规划模型,再根据目标整数线性规划模型进行调度。实验结果表明,该算法能保证实时业务分组在延迟期限内传输,适用于实时业务,能确保公平性,最小化分组丢弃,具有较好的适用性。     

MIMO-OFDM系统中的资源调度研究

资源调度对实现资源的有效利用,保证业务的服务质量起着重要作用。分别从非实时业务、实时业务和混合业务三个方面研究了MIMO-OFDM系统中的资源调度;对非实时业务和实时业务单一存在的情况,介绍了传统的经典算法;重点分析了混合业务调度算法的特点。     

硬实时系统中基于任务同步及节能的动态调度算法

提出基于任务同步及节能的动态实时调度算法HDSA(hybrid dynamic scheduling algorithm),以有效地解决任务同步及节能的难题.HDSA 结合RM及EDF算法,在满足任务实时可调度性及任务同步的限制条件下,采用DVFS节省能耗.HDSA包含静态算法及动态算法两部分.静态算法在静态条件下,求出任务的静态速度.动态调度算法在实际运行中,固定临界区的运行速度,并充分回收、利用任务运行时的空闲执行时间,调节处理器的速度,以有效降低能耗并满足实时可调度性.同时避免高优先权任务被阻塞时,临界区继承高优先权任务的速度时所造成的处理器电压开关的频繁切换,因而能有效地降低实时任务调度的成本.实验测试表明,HDSA在调度性能上明显优于目前所知的有效算法.     

WiMAX系统中QoS机制研究

文章分析了WiMAX系统QoS机制的主要内容:业务流管理、QoS保证算法,探讨了QoS机制对主动授权、实时查询、非实时查询和尽力而为等数据业务的支持.为了让不同业务的QoS得到保证,文章重点探讨了基于信道状态的分组调度算法(CSDPS)、基于业务类型排队(CBQ)的CSDPS调度算法和通用处理器共享策略,并给出了相应的算法模型.     

星上Clos交换网络的分治调度算法

针对星上交换的特殊要求,该文提出了基于MSM (Memory-Space-Memory)型Clos交换网络的分治调度算法。通过引入冲突域的概念,分治调度算法将MSM型Clos网络中的匹配问题分解成在冲突域内为每个中间级模块选择信元的问题。该调度算法限制了冲突发生的范围,简化了调度的复杂度,并且具有硬件实现简单、能适应多种业务等优点。仿真表明,分治调度算法在各种业务模型下的吞吐率都能接近100%,并具有良好的时延性能,满足了卫星通信的要求。     

基于时延和速率效用函数的LTE无线资源调度算法研究

为了提高LTE实时业务调度的公平性,在M-LWDF资源调度算法的优先级判断机制中引入了平均传输速率和保证比特速率,将经济学中的效用思想和效用函数引入M-LWDF调度算法,提出了一种基于时延效用函数和速率效用函数的M-LWDF改进算法,更好地体现了调度算法的时延特性和速率特性。仿真结果表明基于时延和速率效用函数的M-LWDF调度算法具有更高的公平性,能够更好地满足对实时业务的调度要求。     

提供区分服务的可抢占信道调度算法

在OBS网络LAUC-VF信道调度算法的基础上,提出了一种新的能够提供区分服务的可抢占武信道调度算法,它既保证了高优先级业务的低延迟传输,也使低优先级的业务能与高优先级业务共享信道资源,从而改善了OBS网络的QoS特性.     

E-UTRA中一种多业务两步比率公平调度算法

符合3GPP多业务处理原则的子信道调度方案是影响E-UTRA系统性能的关键技术。为减少填充和提高多用户分集效应,提出了一种多业务两步比率公平调度算法。在不区分用户业务优先级的情况下,先采用实际缓存量替代传统比率公平算法中的传输速率来分配子信道;业务优先级高的未分配用户再按比率公平算法确认的优先权重从低到高来挤占业务优先级低的用户所分配的子信道,从而确保符合3GPP提出的服务完高优先级业务后再服务低优先级业务的多业务处理原则。仿真结果表明,该算法能在保证用户公平的基础上提高系统吞吐量。     

基于实时业务挤占的OFDMA系统的无线资源分配方案

为了在实时业务和非实时业务共享无线资源的场景中增加系统吞吐量,该文提出了一种基于实时业务挤占的无线资源分配方法,该方案首先实施统一调度,然后进行实时业务挤占过程。在保证对实时业务服务的情况下,实时业务挤占的无线资源分配方案提高了多用户分集效果,增加了系统的吞吐量。理论和仿真分析表明,与已有的传统的实时业务和非实时业务共享无线资源的调度方案相比,该方案能够提供更高的系统吞吐量和频谱效率。在实际应用中,该方案具有一定的可行性和可操作性。     

Monitoring and Troubleshooting in Operational IP-TV System

When deploying large scale of QoS guaranteed IP-TV services over Triple-Play networks, there is a growing demand to access to the live network services, monitor in real time the broadcast chains, acquire the dynamic network parameters to ensure an uninterrupted, high quality service. Considering the difference of IP packet switching network and the de-facto transport stream (TS) standard of broadcast digital video network, this paper describes design consideration and implementation of a powerful embedded IP-TV monitor for real time monitoring the IP-TV QoS and using this equipment to construct a payload-aware monitoring network for on-line troubleshooting when the QoS deteriorate. The monitor should be designed to have ability to monitor and troubleshoot the blended combination of network status and digital TV quality in real time and cross layer way, meanwhile the procedures of monitoring does not interfere with the on-line services. This monitor can be deployed in the networks to measure the three ultimate metrics: IP cumulative jitter, packet loss and MPEG TS errors and provide helpful information about the network and service when service failed. Implementation and experimental results show promise of being practical in the real IP-TV trial networks.     

用于业务建立和修改的智能网络软件工厂

本文介绍了一种智能网络软件工厂，一个软件工厂实际上是软件生产过程的集成，这种工厂能业务的设计数据，基本数据，实时数据表格，屏幕和ＳＳＰ呼和以及业务应用的结构、程序、模块和它们的逻辑连接，有了这样软件工厂就能快速地建立、开发、修改和测试各种业务。     

An opportunistic routing mechanism for real‐time voice service in mobile ad hoc networks

The opportunistic routing mechanism can use several lossy broadcast links to support reliable transmission. In this paper, a simple opportunistic routing mechanism for real‐time multimedia services is proposed. This mechanism is based on the dynamic source routing protocol with some modifications, multiple route request, and route reply messages are used to construct the forwarder list, and the nodes within the forwarder list forward the packets which they overhear. The forwarder list is placed on the packet header in the form of a Bloom filter, which will restrict the size of the forwarder list to a constant value. There are no strict scheduling mechanisms for the forwarding order of the forwarder nodes, thus our opportunistic routing mechanism can be scalable for multiple simultaneous flows. Simulations show that our mechanism can effectively decrease the transmission times and the amount of the control messages for each packet and reduce the end‐to‐end delay for real‐time voice service, the quality of service for these services can be supported well over the unstable wireless channel. Copyright © 2009 John Wiley & Sons, Ltd.     

The study of QoS guarantee in the optical burst switching internet backbone

Optical switching technology can be categorized into optical circuit switching (OCS), optical packet switching (OPS) and optical burst switching (OBS). OCS is suitable for large amounts of data transmission; however, the channel utilization is inefficient when the traffic flows are intermittent. OPS can be easily adapted to any higher layer and is suitable for bursty traffic, but it requires a highly complex technology and optical buffer. The new switching paradigm, OBS, can provide higher bandwidth utilization and meanwhile avoid the complexity in OPS technology.In this paper, we investigate how the quality of service (QoS) can be guaranteed and reliable transmission can be supported in the OBS-based Internet backbone. We propose the adjustable-time-counter-based (ATCB) burst assembly and the non-real time packet retransmission mechanisms and apply them in the ingress router of the OBS Internet backbone to guarantee the quality of real time applications and lossless requirement of non-real time services. Moreover, traffic shaped is performed for real time packets in the egress router so that the real time property is preserved with a low jitter. Simulation results show that the burst blocking probability using the ATCB burst assembly is improved, compared with the time-counter-based (TCB) and burst-length-threshold-based (BLTB) mechanisms. The delay, loss and jitter of real time service conform to the QoS requirement. Meanwhile, the delay of non-real time service also falls in the acceptable range.     

下一代互联网研究方向与趋势

"业务综合"和"网络融合"是通信界多年来努力的目标。IP网络具有承载包括语音、数据和视频等多种业务应用能力,这使业界将全IP网络看作是未来融合网络的雏形。但目前的IP网络无法保证实时业务的服务质量以及网络和业务的安全性。为了在下一代互联网发展方面处于领先地位,全球各国都在不断投入力量进行下一代互联网的研究工作。本文主要介绍IP网络和业务的发展情况、目前IP网络存在的问题以及全球在发展下一代互联网方面所做的努力。     

基于BCMCS的精密定位信息移动广播方案设计

主要研究在CDMA2000 1xEV-DO网络中建立基于BCMCS的移动广播网络方案,具体内容包括了BCMCS的介绍,广播方案的网络拓扑、基本流程图和关键技术等。方案将应用于定位信息分发业务当中,实现将从大众导航与位置服务信息处理服务中心获得的精密定位信息实时送达到用户移动终端上,解决定位信息分发业务无法实现大规模用户和快速实时送达的不足,实现更高效的传输。     

On the impact of correlated arrivals and errors on ARQ delay terms

We analytically investigate the packet delay statistics of the Selective Repeat ARQ scheme with non-instantaneous feedback, with correlation both in the channel errors and the packet arrival process. We highlight interesting trends of the delay terms, which can be extremely useful for multimedia real time services over wireless.     

大数据系统在IPTV/OTT用户行为调查上的应用

描述利用大数据技术实现用户行为和收视率调查方案的系统设计。受益于宽带网络的发展和IPTV/OTT智能终端的双向互动特性,用户操作使用电视的行为数据可以实时传送到位于云端的大数据平台,大数据分析系统通过分析这些海量用户数据,得到精准的用户收视行为的实时数据。相比传统的基于抽样样本统计方法的局限和偏差,大数据的分析方法使用全样本数据,保障了统计的全面性和准确性,同时还可以为每一个具体用户画像,这样的统计和画像为运营商对节目、频道的运营提供了准确实时的参考数据,为运营商优化内容、广告的投放提供了有效的手段和工具,从而可以大大提升运营商的竞争力。     

Identifying critical challenges in the adoption of cloud‐based services

Cloud computing provides a way to integrate and share information on a real‐time basis across an organization. The current organizations are adopting the cloud services to gain competitive advantage in real‐time data sharing. To meet the current demand in semiconductor industries, they must develop better techniques to produce electronic products at low cost and in a large scale. Adoption of cloud‐based services may resolve the fastest growing demand of technical advancement of semiconductor industries. The research presented in this paper is based on an analysis of the data obtained from the semiconductor sector. This study identifies the critical challenges associated with the cloud service adoption in semiconductor industries. Twelve critical challenges have been identified that need to be overcome for adopting the cloud services for any semiconductor industry. These are network/Internet availability, data security, integration of various services, monitoring of data and services, maintenance of computing performance, liability, power outage, service interruption, organizational change, business complexity, legal issues, and lack of awareness.