發(fā)布時間：2018-04-28 04:50

  本文選題：無線網(wǎng)絡 + 流媒體�。� 參考：《重慶大學》2014年碩士論文

【摘要】：流媒體技術(shù)的廣泛應用和移動互聯(lián)網(wǎng)的高速發(fā)展，使得人們對移動流媒體服務的需求越來越大。大量的流媒體數(shù)據(jù)在網(wǎng)絡中傳播，現(xiàn)有的網(wǎng)絡資源不足以滿足如此大量數(shù)據(jù)的并行傳輸，從而產(chǎn)生了網(wǎng)絡擁塞。對網(wǎng)絡擁塞控制的研究已經(jīng)持續(xù)了十幾年，但這類研究并沒有針對流媒體數(shù)據(jù)傳輸?shù)奶攸c進行優(yōu)化，特別是在流媒體傳輸?shù)膿砣A防和流媒體服務質(zhì)量的保障上，與實際需求有一定的差距。無線網(wǎng)絡環(huán)境下的擁塞控制研究更是其中的難點和熱點之一，也是推動移動流媒體服務發(fā)展的重點。 本文主要研究無線網(wǎng)絡環(huán)境下流媒體傳輸擁塞控制的特點、問題以及解決方法，在對TFRC（TCP Friendly Rate Control Protocol）協(xié)議研究的基礎(chǔ)上，設計了一種TCP友好的無線流媒體傳輸擁塞控制系統(tǒng)。本文主要完成的研究工作如下： （1）分析了無線網(wǎng)絡的特點以及無線網(wǎng)絡環(huán)境下數(shù)據(jù)包丟失的原因；闡述了流媒體傳輸原理、技術(shù)和特點；分析了擁塞控制機制以及擁塞產(chǎn)生的原因，并給出了擁塞控制機制的評價標準。 （2）詳細分析了TFRC中TCP吞吐量計算方法、TFRC數(shù)據(jù)包內(nèi)容和TFRC的工作流程，針對TFRC應用于流媒體傳輸時存在的問題，對TFRC在擁塞預警、傳輸平穩(wěn)性和最小發(fā)送速率等方面的不足進行了相應的改進。 （3）針對無線網(wǎng)絡環(huán)境對于TFRC性能的影響，提出了利用ECN（ExplicitCongestion Notification）的特性來進行丟包區(qū)分的方法，該方法可以正確區(qū)分擁塞丟包和無線誤碼丟包，根據(jù)該方法研究了一種基于ECN的擁塞控制機制及其在Linux系統(tǒng)的實現(xiàn)，并在此基礎(chǔ)上設計了TCP友好的無線流媒體擁塞控制系統(tǒng)。 （4）對設計的無線流媒體擁塞控制系統(tǒng)進行了測試，依據(jù)擁塞控制機制的評價標準，，進行了網(wǎng)絡效率、TCP友好性、流媒體播放平穩(wěn)性和流媒體播放效果等測試并對測試結(jié)果進行了分析，測試結(jié)果表明本文研究設計的無線流媒體擁塞控制系統(tǒng)達到了預期的設計效果，對同類系統(tǒng)在流媒體傳輸效果和應用于無線網(wǎng)絡環(huán)境中的性能等方面有顯著提高。 綜上所述，本文對無線網(wǎng)絡環(huán)境下的流媒體傳輸擁塞控制進行了深入研究，并針對現(xiàn)有擁塞控制方法的不足進行了相應改進并設計了無線流媒體擁塞控制系統(tǒng)，最后通過實驗驗證了新方法的有效性，表明本文設計的無線流媒體擁塞控制系統(tǒng)能夠在TCP友好的前提下，保證無線網(wǎng)絡環(huán)境下流媒體服務的質(zhì)量。
[Abstract]:With the wide application of streaming media technology and the rapid development of mobile Internet, people need more and more mobile streaming media services. A large number of streaming media data spread in the network, the existing network resources are not enough to meet the parallel transmission of such a large number of data, resulting in network congestion. The research on network congestion control has lasted for more than ten years, but this kind of research has not optimized the characteristics of streaming media data transmission, especially in the congestion prevention of streaming media transmission and the guarantee of streaming media quality of service. There is a certain gap with the actual demand. The research of congestion control in wireless network environment is one of the difficulties and hot spots, and it is also the key to promote the development of mobile streaming media services. This paper mainly studies the characteristics, problems and solutions of congestion control of streaming media transmission in wireless network environment. Based on the research of TFRC(TCP Friendly Rate Control Protocol) protocol, a TCP friendly congestion control system for wireless streaming media transmission is designed. The main work of this paper is as follows: 1) analyzing the characteristics of wireless network and the reasons of packet loss in wireless network environment, expounding the principle, technology and characteristics of streaming media transmission, analyzing the congestion control mechanism and the causes of congestion. The evaluation criteria of congestion control mechanism are also given. In this paper, the method of TCP throughput calculation in TFRC is analyzed in detail, including the content of TCP packet and the workflow of TFRC. Aiming at the problems existing in the application of TFRC in streaming media transmission, the congestion warning of TFRC is given. Some improvements have been made in terms of transmission smoothness and minimum transmission rate. 3) aiming at the influence of wireless network environment on TFRC performance, this paper proposes a method of packet loss discrimination by using the characteristics of ECN(ExplicitCongestion Notification, which can correctly distinguish congestion packet loss from wireless error packet loss. According to this method, a congestion control mechanism based on ECN and its implementation in Linux system are studied, and a TCP friendly congestion control system for wireless streaming media is designed. (4) the designed wireless streaming media congestion control system is tested. According to the evaluation standard of congestion control mechanism, the network efficiency and TCP friendliness are carried out. The test results show that the wireless streaming media congestion control system designed in this paper has achieved the desired design effect. The performance of similar systems in streaming media transmission and wireless network environment has been improved significantly. To sum up, this paper deeply studies the congestion control of streaming media transmission in wireless network environment, and improves the existing congestion control methods and designs the wireless streaming media congestion control system. Finally, the effectiveness of the new method is verified by experiments, which shows that the proposed wireless streaming media congestion control system can guarantee the quality of streaming media service in wireless network environment on the premise of TCP friendly.
【學位授予單位】：重慶大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TN919.8

【參考文獻】

相關(guān)期刊論文 前10條

1 張麗娟;楊曉萍;陳虹;張振宇;;基于自適應參數(shù)設置的AIMD算法[J];吉林大學學報(信息科學版);2010年01期

2 袁浩;杜茂康;李昌兵;;一種適用于無線網(wǎng)絡流媒體傳輸?shù)母倪MTFRC協(xié)議[J];哈爾濱理工大學學報;2011年02期

3 武航星;慕德俊;潘文平;喬梅梅;;網(wǎng)絡擁塞控制算法綜述[J];計算機科學;2007年02期

4 楊格蘭;曹理宇;張建明;;基于MPEG-4的流媒體服務器端緩沖區(qū)管理[J];計算機工程;2007年05期

5 邵立松;張鶴穎;竇文華;;基于窗口的端到端擁塞控制:網(wǎng)絡穩(wěn)定性與效率[J];計算機學報;2006年03期

6 武航星;慕德俊;龔賢武;潘文平;;TCP的RTT不公平性問題模型分析與仿真[J];計算機仿真;2008年09期

7 張曉;胡維華;徐小良;;基于RTCP的移動流媒體研究[J];計算機仿真;2009年05期

8 劉吉成;耿少峰;李仁發(fā);;基于TFRC協(xié)議的視頻自適應傳輸機制及仿真實驗[J];計算機應用研究;2011年12期

9 章民融;徐亞鋒;;基于RTSP的流媒體視頻服務器的設計與實現(xiàn)[J];計算機應用與軟件;2006年07期

10 鄭晶晶;李洪霞;;流媒體系統(tǒng)引入RSVP協(xié)議的實現(xiàn)方法[J];計算機工程與設計;2006年08期

相關(guān)博士學位論文 前1條

1 葉進;無線/有線混合網(wǎng)絡中傳輸控制協(xié)議的研究[D];中南大學;2008年

本文編號：1813837