【摘要】：網(wǎng)絡(luò)技術(shù)的飛速發(fā)展使得業(yè)務(wù)種類日漸豐富多彩,業(yè)務(wù)數(shù)量呈現(xiàn)爆發(fā)式增長。在眾多的業(yè)務(wù)種類中,流媒體業(yè)務(wù)以其直觀、生動、實(shí)時(shí)、方便的特點(diǎn)吸引了廣泛用戶。使用互聯(lián)網(wǎng)請求流媒體視頻的用戶數(shù)和業(yè)務(wù)量日益增長,尤其是直播流媒體視頻傳輸?shù)男枨笤黾语@著,如何利用因特網(wǎng)高效傳輸流媒體直播視頻成為一個(gè)重要問題。 與傳統(tǒng)的服務(wù)器-客戶端模式相比,對等網(wǎng)絡(luò)(Peer-to-Peer, P2P)應(yīng)用被看作是更具可擴(kuò)展性和成本效益的方案。由于每個(gè)加入到P2P的用戶即作為客戶端又作為服務(wù)器,這使得源服務(wù)器的壓力大大降低。一般來說,P2P系統(tǒng)的服務(wù)能力會隨用戶數(shù)量的增加而提升,越多用戶加入到P2P系統(tǒng),可用的上行帶寬就越多。 雖然當(dāng)前的P2P視頻直播系統(tǒng)展現(xiàn)出了高效地將視頻內(nèi)容直播給眾多互聯(lián)網(wǎng)用戶的潛力,但是已成功部署的P2P直播系統(tǒng)存在嚴(yán)重的問題： 首先,當(dāng)前的P2P應(yīng)用缺少物理位置感知：當(dāng)前的P2P直播系統(tǒng)缺少Peer節(jié)點(diǎn)物理位置感知能力,因此構(gòu)建P2P邏輯網(wǎng)絡(luò)時(shí)往往采取隨機(jī)選擇鄰居關(guān)系的策略,使得P2P系統(tǒng)中交換直播數(shù)據(jù)塊的鄰居經(jīng)常是跨運(yùn)營商、跨區(qū)域的。直播數(shù)據(jù)塊傳輸經(jīng)常要經(jīng)歷多跳路由,對網(wǎng)絡(luò)傳輸帶寬、交換設(shè)備計(jì)算資源造成極大浪費(fèi)。 其次,當(dāng)前的P2P直播系統(tǒng)缺少動態(tài)調(diào)度功能：由于沒有主動測量Peer節(jié)點(diǎn)交換數(shù)據(jù)使用的路徑,沒有對擁塞路徑做出及時(shí)調(diào)整,當(dāng)前P2P直播系統(tǒng)不能達(dá)到數(shù)據(jù)傳輸路徑最優(yōu)。P2P直播系統(tǒng)與其他P2P業(yè)務(wù)的不同之處是,直播系統(tǒng)對數(shù)據(jù)傳輸延遲的敏感度更高。因此,及時(shí)探測出現(xiàn)網(wǎng)絡(luò)擁塞的路徑,并將直播數(shù)據(jù)包的傳輸路徑轉(zhuǎn)移到負(fù)載較輕的路徑上,能夠有效降低直播數(shù)據(jù)傳輸延遲,極大提升P2P直播系統(tǒng)的性能。 本文提出在軟件定義網(wǎng)絡(luò)(Software-Defined Network,SDN)中部署P2P直播系統(tǒng)的方案——OpenP2P,可以有效解決當(dāng)前P2P直播系統(tǒng)中存在的問題。在OpenP2P系統(tǒng)中,SDN控制器為P2P直播系統(tǒng)的Tracker服務(wù)器提供物理網(wǎng)絡(luò)拓?fù)湟晥D,使Tracker服務(wù)器為加入P2P網(wǎng)絡(luò)的Peer節(jié)點(diǎn)選擇物理位置最近、傳輸直播數(shù)據(jù)消耗帶寬費(fèi)用最少的節(jié)點(diǎn)作為鄰居。另外,通過設(shè)計(jì)SDN控制器模塊使其能夠探測出網(wǎng)絡(luò)鏈路的傳輸延遲性能,對出現(xiàn)擁塞的傳輸路徑進(jìn)行動態(tài)調(diào)整,使用較輕負(fù)載的路徑代替擁塞路徑傳輸直播數(shù)據(jù)片段,實(shí)現(xiàn)數(shù)據(jù)傳輸最優(yōu)化。實(shí)驗(yàn)結(jié)果表明,OpenP2P與傳統(tǒng)P2P直播系統(tǒng)相比,在帶寬費(fèi)用消耗與直播數(shù)據(jù)塊傳輸延遲方面,性能明顯得到了提升。
[Abstract]:With the rapid development of network technology, the types of business are becoming more and more colorful, and the number of services is increasing rapidly. Streaming media service attracts a wide range of users because of its intuitionistic, vivid, real-time and convenient characteristics. The number of users and traffic requesting streaming media video using Internet is increasing day by day, especially the demand of live streaming video transmission is increasing significantly. How to use the Internet to transmit live streaming video efficiently becomes an important problem. Compared with the traditional server-client model, Peer-to-Peer, P2P (Peer-to-Peer) application is regarded as a more scalable and cost-effective solution. Because each user joins P2P as both client and server, the pressure of source server is reduced greatly. Generally speaking, the service capability of P2P system will be improved with the increase of the number of users. The more users join P2P system, the more available uplink bandwidth will be. Although the current P2P video broadcast system has demonstrated the potential to broadcast video content efficiently to many Internet users, the successfully deployed P2P live broadcast system has serious problems: first, The current P2P applications lack physical location awareness: the current P2P live broadcast system lacks the physical location awareness ability of Peer nodes, so the strategy of randomly selecting neighbor relationships is often adopted when constructing P2P logical networks. The neighbors who exchange live data blocks in P2P system are often cross-operator and cross-region. Live data block transmission often goes through multi-hop routing, resulting in a great waste of network transmission bandwidth and switching equipment computing resources. Secondly, the current P2P live broadcast system lacks the dynamic scheduling function: because there is no active measurement of the path used by Peer nodes to exchange data, there is no timely adjustment to the congestion path. The difference between P2P live broadcast system and other P2P services is that the live broadcast system is more sensitive to the delay of data transmission. Therefore, detecting the path of network congestion in time and transferring the transmission path of live broadcast data packet to the path with less load can effectively reduce the transmission delay of live broadcast data and greatly improve the performance of P2P live broadcast system. In this paper, a scheme of deploying P2P live broadcast system in software defined network (Software-Defined Network,SDN), OpenP2P, is proposed, which can effectively solve the problems existing in current P2P live broadcast system. In the OpenP2P system, the SDN controller provides a physical topology view for the Tracker server of the P2P live broadcast system, which enables the Tracker server to select the nearest physical location for the Peer node joining the P2P network. The nodes that consume the least bandwidth to transmit live data are neighbors. In addition, the SDN controller module is designed so that it can detect the transmission delay performance of the network link, dynamically adjust the transmission path with congestion, and use the path with lighter load instead of the congestion path to transmit live data fragments. The optimization of data transmission is realized. The experimental results show that compared with the traditional P2P live broadcast system, the performance of OpenP2P has been improved obviously in terms of bandwidth cost consumption and transmission delay of live broadcast data blocks.
【學(xué)位授予單位】：北京郵電大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN919.8

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 彭凱;武娟;楊宗凱;唐宏;;基于P2P的流媒體直播技術(shù)研究與展望[J];計(jì)算機(jī)科學(xué);2009年01期

2 左青云;陳鳴;趙廣松;邢長友;張國敏;蔣培成;;基于OpenFlow的SDN技術(shù)研究[J];軟件學(xué)報(bào);2013年05期

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本文編號：2434221