Analysis and Taxonomy of Congestion Control Mechanisms for Internet Reliable Multicast

The research of congestion control for Internet reliable multicast is one of the most active fields in reliable multicast protocol research. Many reliable multicast congestion control mechanisms have been put forward. In this paper we present principal problems of congestion control for Internet reliable multicast, analyze solutions and difficulties of solving these problems, and then give a classification of some reliable multicast congestion control mechanisms. Lastly the future work is proposed.

Reliable adaptive multicast protocol in wireless Ad hoc networks

In wireless ad hoe network environments, every link is wireless and every node is mobile. Those features make data lost easily as well as multicasting inefficient and unreliable. Moreover, Efficient and reliable multicast in wireless ad hoe network is a difficult issue. It is a major challenge to transmission delays and packet losses due to link changes of a multicast tree at the provision of high delivery ratio for each packet transmission in wireless ad hoe network environment. In this paler, we propose and evaluate Reliable Adaptive Multicast Protocol （RAMP） based on a relay node concept. Relay nodes are placed along the multieast tree. Data recovery is done between relay nodes. RAMP supports a reliable multicasting suitable for mobile ad hoe network by reducing the number of packet retransmissions. We compare RAMP with SRM （Scalable Reliable Multicast）. Simulation results show that the RAMP has high delivery ratio and low end-to-end delay for packet transmsission.

Reliable Battery-Aware Cooperative Multicasting for MBS WiMAX Traffic

Recently, relay agents selection schemes were introduced to support downlink multicasting in WiMAX single frequency networks. Such schemes were devised to work cooperatively in order to facilitate reliable Multicast Broadcast Multimedia Services (MBMS) traffic delivery over wireless channels without any consideration to mobile relay agents’ battery energy levels. In this paper, we introduce a battery-aware balancing algorithm to operate in conjunction with these relay agents selection schemes proposed in the open literature. A simulation model, used to present the effect of “before” and “after” the battery–awareness selection criterion, highlighted the benefit of using such algorithms in prolonging network lifetime with emphasis on reliable delivery.

Cooperative Loss Recovery for Reliable Multicast in Ad Hoc Networks

Providing reliable multicast service is very challenging in Ad Hoc networks. In this paper, we propose an efficient loss recovery scheme for reliable multicast (CoreRM). Our basic idea is to apply the notion of cooperative communications to support local loss recovery in multicast. A receiver node experiencing a packet loss tries to recover the lost packet through progressively cooperating with neighboring nodes, upstream nodes or even source node. In order to reduce recovery latency and retransmission overhead, CoreRM caches not only data packets but also the path which could be used for future possible use to expedite the loss recovery process. Both analytical and simulation results reveal that CoreRM significantly improves the reliable multicast performance in terms of delivery ratio, throughput and recovery latency compared with UDP and PGM.

Efficient network coding-based retransmission algorithm for reliable wireless multicast

Recent research shows using network sion efficiency in wireless networks greatly et for retransmission over composite fading coding for reliable multicast can improve the retransmis- In this paper, we study how to code the composite pack- channels efficiently. For the composite fading environ- ment with muhiple receivers, receivers experience different fading at any time. It＇ s very important to code the composite packet so that intended receivers are in good channel qualities, because in- tended receivers in deep fading have little opportunity to receive the composite packet correctly. Hence, we propose a novel composite packet coding principle of maximizing the total SNR of intend- ed receivers. Since the proposed principle is an NP-complete problem, an efficient heuristic algo- rithm with low complexity is given for finding a suboptimal solution. Simulation results show the heu- ristic based scheme achieves higher transmission efficiency than other network coding-based schemes due to the multi-user diversity gain.

IPv4 Based Reliable Mobile Multicast Technology

The mobile multicast technology has been a research hotspot in the wireless Internet field in recent years.Quite a large part of its applications requires the reliability in a mobile environment to be equivalent to that provided by wireline links.However,the inherent features of a mobile environment,that is,high error rate of links and dynamically changing multicast members’ locations,are great difficulties for mobile multicast,let alone reliable mobile multicast.The IPv4-based reliable mobile multicast algorithms come with two different design philosophies.A part of the algorithms is to be improved for better reliability by solving existing algorithm-related problems;while other algorithms are to implement reliable mobile multicast with new function entities introduced to guarantee reliability.

海事卫星地面站RMS可用性评估模型

随着国际海事卫星通信系统(international maritime satellite communication system,INMARSAT)的不断发展,卫星地面站(satellite earth station,SES)的可用性评估具有重要意义。首先选取可靠性、维修性和保障性为指标,构建可靠性、维修性与保障性(reliability,maintainability and supportability,RMS)模型进行SES可用性评估;其次,以SES设备为研究对象,根据马尔可夫链得到设备有效性概率,并进一步推导出系统可靠性;然后,建立排队图解协调技术(queue-graphical evaluation and review technique,Q-GERT)网络以描述SES设备的维修保障过程,并基于AnyLogic软件进行建模仿真;最后,通过算例进行应用研究,基于RMS模型进行SES可用性评估,验证了该模型和评估方法的有效性与实用性。

A Reliable Adaptive High-Definition Transmission System for Distance Learning

There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay.

基于HSRM的分布式发言权控制模型与应用研究

研究了组播会话对发言权控制和网络通信的要求。提出了一个满足这种要求的可靠组播通信模型HSRM,然后结合所研制的基于IP组播的协同学习环境WebLearning+的应用背景给出了基于HSRM的发言权控制模型。该模型协议一致,可以方便地扩展到无主持人和多主持人模式,失效恢复简单,加入和退出灵活,有很好的可扩展性和鲁棒性。

直升机RMS与测试性综合评估模型研究

通过对直升机可用性,可靠性、维修性、保障性(reliability&maintainability&supportability,RMS)和测试性的研究,提出对可用性进行综合评估,并说明在RMS基础上考虑测试性的必要性。首先,根据RMS与测试性的常用参数,建立了可用性综合评估指标体系;其次,在现有多种综合评估方法中,选择模糊层次分析法(即层次分析法(analytic hierarchy process,AHP)与模糊综合评估法(fuzzy comprehensive evaluation,FCE)相结合的方式)对直升机可用性进行评估,从而构建了总体综合评估模型;最后,应用Matlab平台对提出的评估模型进行仿真,并以直11型直升机为例对提出的方法进行验证,实现了评估的自动化与可视化。

HSRM:一个适合组播会议控制的可靠组播通信模型

研究了组播会议控制对网络通信的要求 .针对这一背景 ,提出了一个新的基于接收方丢失报文概率分组的可扩展可靠组播通信模型 HSRM,设计了其分层结构的动态构建和维护策略 ,并进行了数值仿真 .HSRM使用全分布方式和一致的组播通信构造与发送者无关的分层结构 ,限制了反馈和修复报文的扩散范围并控制了组内节点的异构性和组播组的规模 .在保持良好鲁棒性、可扩展性和灵活性的前提下 。

雷达装备RMS参数体系论证

针对雷达装备RMS(可靠性、维修性、保障性)参数体系研究中出现的完备性问题和针对性问题,分析了雷达装备的任务需求,研究了雷达装备RMS参数选取的原则,按RMS综合参数、RMS单项参数(可靠性参数、维修性参数、测试性参数)、保障系统及保障资源参数5类,建立了雷达装备RMS参数体系。在此基础上,重点对参数之间的相互关系进行了图形化描述,对影响雷达装备任务完成的关键性参数进行了建模。该参数体系及参数间相互关系的说明可为雷达装备RMS要求论证提供依据。

地空导弹武器装备RMS论证参数体系研究

通过对地空导弹武器装备RMS(可靠性、维修性、保障性)参数存在的问题进行分析,提出了RMS参数的选取原则,并建立了地空导弹武器装备RMS参数体系,为装备可靠性、维修性、保障性论证奠定了基础,该体系的建立有助于提高武器装备战备完好性、任务成功性,减低使用维修人员和保障资源费用。

RMTP协议的时延分析

RMTP(reliable multicast transport protocol)是一种通过修复服务器(repair server)本地恢复来提供可靠性的组播协议.对改进的RMTP协议的时延性能进行建模分析.推导了数据包自发送主机发出到成功地被一个随机选择的接收主机接收之间的平均时延公式.分析表明,随着丢失率的增长,RMTP的时延性能恶化点将迅速下降;随着每个修复服务器下连接尾链路数量的增加,RMTP的时延性能恶化点也将下降.但是,随着尾链路总数量的增加而保持每个修复服务器连接的尾链路数量不变,RMTP的时延性能的变化很小.仿真结果较好地验证了分析的有效性.

基于STEP的RMS信息模型研究及实现

为了满足产品数字化协同研制模式对可靠性、维修性、保障性(RMS)数据共享和交换的要求,针对RMS工程的“全特性”、“全阶段”和“全系统”的特点,建立了基于产品模型数据交换标准(STEP)的RMS信息模型,并研究提出了该模型在产品数据管理系统(PDM)下的实现方法,最后给出了RMS模型及其实现方法在企业信息集成中的应用模式及案例验证。

基于SoSE的装备体系RMS论证方法研究

装备体系可靠性、维修性、保障性(reliability-maintainability-supportability,RMS)是装备体系作战效能发挥的基础。体系工程中需求开发过程从能力要求分析开始,然后进行体系结构建模并基于体系结构给出需求方案。装备体系RMS论证即是对装备体系RMS能力要求进行分析并提出RMS指标,也遵循这一过程。首先,基于SoSE需求开发过程和装备体系特点给出装备体系RMS论证框架。接着,基于质量功能展开方法给出装备体系RMS能力要求分析过程,从装备体系使命任务出发,建立装备体系RMS能力要求映射模型,并提出相应的RMS能力指标求解方法。然后,基于面向RMS的装备体系结构框架,将RMS能力分析得出的初步RMS能力指标作为输入,基于多智能体仿真技术提出美国国防部体系架构驱动的装备体系RMS仿真框架,从而通过仿真权衡论证出最终的装备体系RMS指标。最后,对典型使命任务下的航母装备体系舰载机保障过程进行了案例分析。

HSRM层次化结构的动态构建和维护

HSRM是我们针对分布式组播会议控制的应用需求提出的层次化可扩展可靠组播通信模型 .本文根据分布式组播会议控制在分布性、可扩展性和鲁棒性等方面的要求 ,以分布、基于组播、自适应、公平和自治为目标 ,设计了HSRM层次化结构的分布式、自适应构建和维护算法 .

Multicast中的多级反馈抑制方法

分析了Ｍｕｌｔｉｃａｓｔ中的ＡＣＫ和ＮＡＣＫ的反馈内爆问题，介绍了反馈控制的相关工作，提出了一种多级反馈抑制方法，并给出了分析结果，此方法综合了乐观传送抑制、代表集抑制和非代表集抑制，从而避免ＡＣＫ和ＮＡＣＫ内爆。

基于UML的RMS仿真研究

可靠性维修性保障性(RMS)是影响装备作战使用的重要因素,仿真法是进行武器装备作战使用研究的有效途径。该文在对武器装备作战使用的需求进行分析的基础上,使用UML建立了RMS在装备作战使用中的仿真模型,提出了作战过程中RMS仿真的方法,真实反映了RMS对装备作战使用的影响。

SCSRM:分割连接的卫星可靠组播方案

针对端到端方案在卫星可靠组播中存在的缺点,提出了一种分割连接的卫星可靠组播方案SCSRM,并从差错控制机制、拥塞控制机制、反馈抑制策略等方面对运行于卫星网络部分的传输协议Sat-MTCP进行了详细的设计。仿真结果表明,即使在较差的信道条件下,SCSRM方案也可以达到较好的Goodput性能;由于采用了有效的反馈抑制策略和差错恢复策略,当接收者数量增大时,Goodput性能基本保持平稳,表现出良好的可扩展性;通过可用带宽的合理分配,保证了带宽公平性。