To order to solve above problems , we design a novel rate - based multicast congestion control scheme - rbmcc , which uses the active explicit congestion indication and representative - based feedback control scheme to inform the source of the status of the network , and alternate the send rate by adjusting the packet intervals between packets . the goal of the dynamic congestion control algorithm is to make the entire system responsive to the changes as rapidly as possible in the offered loads or available bandwidth without getting into an oscillating behavior 针对上述算法中存在的动态性、灵敏性以及由之引起的公平性等问题，本文第3章设计了一种新的基于速率的组播拥塞控制机制? ? rbmcc ，该算法利用积极的显式拥塞指示，基于代表的反馈机制，通过调节包与包的发送间隔来改变数据的发送速率，动态地自适应网络拥塞状态的改变。
Then not only i take advantage of the success of the slip window mechanism of tcp , but also do some improvement on the slip window mechanism based on the property of suna , including the computation of rtt , the computation of mss and how to avoid fragment , the value of slip window , the congestion avoidance mechanism . these improve the efficiency of the slip window under suna 然后在借鉴tcp的滑动窗口机制的成功之处的同时,结合服务元网络体系结构的特性对其进行一系列行之有效的改进:包括rtt的计算、 mss的计算和分片的避免、滑动窗口的计算以及拥塞控制机制,这些改进使得服务元网络体系结构下的滑动窗口的效率得到了提高。
In this paper , the streaming media technology applied to network video monitor system are researched on the basis of video streaming . the emphases are put on system design , video captures and play , and the design of network transmission module and relevant software development method . in fact , uality of service of the network has unstable characteristics , we have analyzed qos guarantee strategy in video streaming transmission on network , and presents a integrated qos guarantee scheme which based on data encapsulation , buffer storage technology and congestion control on network . this scheme do its best to avoid the big delay or congestion on network based on make full use of network bandwidth , which can guarantee the best qos of the video transmission 重点讨论了系统架构、视频捕获和播放、网络传输模块设计以及相关软件开发方法。同时,针对实际网络中存在的服务不稳定性特点,分析了视频流在网络传输过程中的qos保证技术,并在系统中提出了基于数据封装、缓存技术以及网络拥塞控制机制的综合qos解决方案。该方案使系统在充分利用网络带宽的情况下最大程度上避免出现大的延迟或拥塞,保证了视频传输的最佳服务质量。
Combining with the evolution of congestion control mechanisms , the existed technologies for congestion avoidance and recovery in ip networks are reviewed . the unsolved problems and hot spots in subdiscipline , such as tcp flow control , end - to - end flow control and enhanced mechanism in intermediate nodes , are summarized , and the advantages and disadvantages of all kinds of schemes for active queue management are emphatically analyzed 本文回顾了ip网络中已有的拥塞控制技术；研究了internet中tcp的基于窗口的端到端拥塞控制方法以及ip层采用的拥塞控制机制，总结了tcp流量控制和中间节点增强机制等各研究子方向中需要解决的问题。
In this article , though reseaching mpls and multicast deeply and analysing the existing mpls mulicast strategy detailedly , a new mpls mulicast strategy is put forward . it applise some existing techniques such as tunnel , aggregation , redundancy and so on to resolve more problem in several aspects . in this funderation , some mechanism is spplied to avoid congestion , which is advantageous to load balance and improve bandwithd efficiency in whole net 在本文中,通过深入研究mpls和组播技术,并在详细分析现有mpls组播技术的基础上提出一种新的mpls组播聚合策略,它采用隧道技术、组播聚合和冗余机制等技术,在多个方面解决了mpls组播所面临的问题,并在此基础上引入拥塞控制机制,以尽量避免由组播流引发的网络拥塞,有助于整个网络的负载平衡和提高网络的使用效率。
The end hosts use transmission control protocol ( tcp ) to implement end - to - end congestion control . it can be said that the success of today ' s internet primarily relies on tcp congestion control mechanisms . with the development of internet and the problems in the implementation of tcp , the current tcp strategies could n ' t meet various demands of users any longer 目前internet仅提供单一的“ besteffort ”服务，其资源分配主要在用户端进行，利用传输控制协议( tcp )进行端到端的拥塞控制，可以说， internet的成功在很大程度上依赖于tcp拥塞控制机制的有效执行，但是由于internet的发展及tcp拥塞控制算法本身存在的问题，使得现有的拥塞控制策略在很多方面已经不能满足人们的需求。
The classical congestion control algorithms for binary abr service mainly based on heuristics and do not have a formal theory to support them , thus they have two drawbacks . one is that the queue length and allowed cell rate ( acr ) oscillate with great amplitude , the other is that the control performance is not as good as we had expected in networks with a long bandwidth delay 但是，传统的二进制abr业务拥塞控制机制大多基于启发式法则而没有正式的理论支持，所以这些方法存在两个不足，一是队列长度和源端允许信元速率呈现振荡性；二是在具有大的带宽时延乘积的网络中，控制效果不佳。
Based on the detail of traditional tcp , the reason of the low throughput and impaired performance of tcp in wireless networks is given , then some solutions are proposed based on the transmission control principle . moreover the impactions of protocols in the lower layers including mac and routing protocol on tcp in ad hoc network are discussed in detail , and the interaction between tcp and mac layer protocols , the affection of route protocols on the performance of tcp and the particular congestion control and error recovery mechanism are first investigated . in this environment an integrated wireless tcp , called iwtcp , is presented to solve the problem about higher bit error rates and disconnection , which emphasizes on the analysis and simulation , the results show that the scheme can greatly improve the performance of tcp , and the realization of iwtcp is given at last 文中主要针对分布式adhoc网络，由于其独特的网络结构，所以我们在分析tcp基本原理的基础上，讨论了传统tcp在无线环境中吞吐量较低、性能恶化的原因，并阐述了无线环境对拥塞控制机制提出的要求，同时就adhoc网络中低层网络协议( mac层和网络层协议)对tcp的影响进行了详细的分析，强调tcp和mac层机制间的相互作用、路由协议中造成adhoc网络中tcp性能降低的原因，并针对现有无线tcp方案不能有效应用于有线无线网络的问题，提出了应用在adhoc网络和internet网络互联环境下的一种综合性tcp解决方案? ? iwtcp ，重点对该方案的性能进行仿真，从理论上分析了性能提高的主要原因，并证明此机制可在很大程度上提高adhoc网络中tcp的性能，最后给出了iwtcp具体软件实现方案。
Because of the unique issues in the networks , including mobility - induced disconnection , network partition , high out - of - order delivery ratios and channel errors , the congestion control and the error recovery in the network is challenging . in this environment , the interaction between tcp and mac layer protocols , the affection of route protocols on the performance of tcp and the particular congestion control and error recovery mechanism are first discussed . then a particular transport layer protocol scheme based on the non - feedback mechanism is presented , with emphasis on the analysis and simulation of the key parameter 文中主要讨论了两种不同网络结构中的无线tcp协议改进方案，其一在最后一跳为无线链路的网络环境中，针对基本tcp拥塞控制机制存在的缺陷，文中在现有解决方案的基础上提出一综合性的方案，其中包括无线链路的高误码率和连接断开问题的解决，并重点对方案中出现的交叉层问题进行分析和仿真；其二，考虑的是分布式网络( adhoc ) ，在文中较为详细的分析了tcp和mac层机制间的相互作用、路由协议中造成tcp性能降低的因素、 adhoc网络中应采取的特殊拥塞控制和差错恢复机制，在此基础上提出了一种采用非反馈机制的解决方案，重点对方案中的关键参数进行分析和仿真，分析和仿真结果表明此机制可在很大程度上提高adhoc网络中tcp的性能。
The mechanism determines the sending rate of video traffic based on packet loss model and feedback information about the network qos provided by rtcp , and then adjusts the sending rate to the available network bandwidth through the use of rate shaping based on the structure of the fgs bitstream , so the optimal video quality is achieved 该拥塞控制机制通过rtcp提供的qos反馈信息和丢包模型来确定视频流的发送速率，并根据fgs码流结构进行码率整形，使得视频流的发送速率能够动态地适应网络带宽的波动，从而最大限度地提高视频质量。
