基于网络编码的光组播网络的动态资源分配研究

发布时间：2018-01-04 22:23

本文关键词：基于网络编码的光组播网络的动态资源分配研究　出处：《北京邮电大学》2014年博士论文　论文类型：学位论文

【摘要】：随着宽带网络的飞速发展,面对新型组播通信业务在整个数据业务中所占比重的不断提高,以及用户对高品质组播质量的追求,导致对网络带宽的要求越来越高,这对传统电域IP组播传输能力提出了巨大挑战。全光组播技术克服了光电光转换对传输速率的限制,成为传输高带宽和高速率组播业务的重要支撑技术,同时将网络编码技术引入到全光组播网络中,能够进一步提高光组播网络的传输效率、容量和健壮性,为高带宽组播问题研究提供一种有效的解决方法。与此同时,伴随着用户个性化,多样化的组播服务需求,不仅要求网络具有支持大容量、高速传输的能力,而且能够高效、可靠、灵活的传送可变速率的多粒度业务。如何面向网络编码为不同粒度的组播业务高效灵活地分配光层资源成为当前需要进一步研究的内容。为了实现多粒度组播业务的高速、高效传输,本文开展了针对全光网络中结合网络编码与正交频分复用(Orthogonal Frequency Division Multiplexing:OFDM)技术的编码机制和资源分配方案的研究,分别实现了物理层的硬件结构设计、控制层中路由和频谱资源分配策略规划以及在无源光网络中解决实际通信问题的应用。主要创新点包括以下内容： (1)针对面向多粒度业务的全光组播网络节点技术进行研究。面向弹性光网络中大容量和多粒度组播业务传输需求,为物理层节点硬件结构设计了一种全光OFDM网络编码机制。提出一种基于OFDM技术的频谱分配方案,能够根据不同传输速率的业务流量动态调整。采用全光器件设计支持多粒度组播业务传输的网络编码节点结构,该结构不仅能够支持更高速率的传输,而且可以改善频谱资源利用效率,兼顾了全光处理、网络编码以及OFDM带来的技术优势。本文分别针对不同速率的组播业务进行传输误码率实验仿真,仿真结果表明多粒度组播业务需求能够被成功的传输,论证了设计结构的可行性,并分析了不同的频谱资源分配方案对组播业务传输性能的影响。另外考虑到实际的全光网络编码结果将受到光信号同步性的要求,在设计方案中提出采用展宽脉冲的处理手段,用以降低脉冲按位对齐的难度,改善全光异或编码运算中的对脉冲错位的容忍度。 (2)针对基于网络编码的光组播资源弹性分配机制进行研究。在全光OFDM网络编码节点结构的硬件支持基础上,本文提出了一种基于网络编码多路传输的路由频谱分配机制(Routing and Spectrum Allocation:RSA)用以作为控制层中的资源配置及优化策略。该机制不仅能够为不同传输速率的组播业务高效、灵活地分配频谱资源,还能够有效地均衡网络负载,提升网络吞吐量,降低阻塞率。本文对提出的RSA机制进行整数线性规划,并将RSA问题分解基于网络编码的路由分配和基于多载波优先的策略的频谱资源分配两个子问题进行优化。通过仿真实验分析系统资源在该分配机制下的传输性能。结果表明：提出的RSA机制能够为不同粒度组播业务灵活高效分配频谱资源,与最短路径树RSA机制和最小生成树RSA机制相比,能够有效节省20%以上的频谱资源,同时有效保证网络负载的均衡性。 (3)针对面向无源光网络的全光组播网络编码应用研究进行研究。提出将全光OFDM网络编码组播机制应用于解决无源光网络(Passive Optical Network:PON)系统中的全光虚拟专用网络(Virtual Private Network:VPN)对等通信的需求。设计方案可以成功实现光网络单元(Optical Network Units:ONU)之间对等通信业务的全双工通信传输,并提高了传输的安全性保证。仿真实验结果说明在PON系统中应用基于OFDM全光网络编码的组播机制具有可行性。新机制的应用不仅能够满足接入网中更高速的对等通信的业务传输需求,而且可以通过增加载波数目和每个载波所承载的传输速率来满足不同速率业务传输的需求。设计方案能够有效支持更灵活的多速率业务传输和频谱分配。
[Abstract]:With the rapid development of the broadband network , the proportion of the new multicast communication service in the whole data service is improved , and the user ' s pursuit of high quality multicast quality results in more and more requirements for the network bandwidth , which overcomes the limitation of the photoelectric conversion on the transmission rate and becomes an important supporting technology for transmitting high bandwidth and high rate multicast service , and simultaneously introduces the network coding technology into the whole optical multicast network , and can further improve the transmission efficiency , capacity and robustness of the optical multicast network , and provides an effective solution for the research of the high bandwidth multicast problem . At the same time , with the personalized and diversified multicast service requirements of the user , not only the network is required to have the capability of supporting large - capacity , high - speed transmission , but also multi - granularity services with variable rate can be transmitted efficiently , reliably and flexibly . In order to realize the high - speed and high - efficiency transmission of multi - granularity multicast service , the coding mechanism and resource allocation scheme for combining network coding and orthogonal frequency division multiplexing ( OFDM ) technology in all optical networks are studied . The hardware structure design of physical layer , the routing of control layer and the application of spectrum resource allocation strategy are implemented respectively . The main innovations include the following : ( 1 ) The technology of all - optical multicast network node oriented to multi - granularity service is studied . A full - optical OFDM network coding scheme is designed for physical layer node hardware in order to meet the demand of large - capacity and multi - granularity multicast service transmission in elastic optical network . A new spectrum allocation scheme based on OFDM technology is proposed . The simulation results show that the multi - granularity multicast service needs can be transmitted successfully . The simulation results show that the multi - granularity multicast service needs can be transmitted successfully . The paper proposes a routing and Spectrum Allocation : RSA , which can effectively and flexibly allocate spectrum resources for multicast service with different transmission rates . It can effectively balance the network load , improve the network throughput and reduce the blocking rate . The proposed RSA mechanism can effectively distribute spectrum resources for different granularity multicast services , and can effectively save more than 20 % spectrum resources for the shortest path tree RSA mechanism and the minimum spanning tree RSA mechanism , and effectively guarantee the balance of network load . This paper studies the application of all - optical multicast network coding in passive optical network ( PON ) system . The design scheme can successfully realize the full - duplex communication transmission between optical network units ( ONU ) and the whole - optical virtual private network ( VPN ) , and improve the security assurance of transmission . The simulation results show that the application of the new mechanism can satisfy the service transmission requirement of the higher speed peer - to - peer communication in the access network . The design scheme can support more flexible multi - rate service transmission and spectrum allocation .

【学位授予单位】：北京邮电大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN911.2

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