【作者】 王鑫；

【导师】 纪越峰；

【作者基本信息】 北京邮电大学 ， 信息与通信工程， 2017， 博士

【摘要】 随着高带宽组播业务的不断兴起,当前光网络的频谱资源难以承受呈指数型增长的带宽需求,本文主要从优化光网络架构和提升频谱资源利用率两个角度解决光资源严重不足的问题。从优化光网络架构的角度,将具有提高网络吞吐量、鲁棒性和均衡网络负载等优势的网络编码融入可高效传送组播业务的弹性组播光网络;从提升频谱资源利用率的角度,在满足业务高效、可靠传输的前提下,同时考虑实际光网络中多种不同类型业务共存,开展了基于网络编码的弹性组播光网络的路由与频谱分配优化研究,以实现频谱资源利用率最大化。本文的主要创新点包括以下内容:(1)基于网络编码的弹性组播光网络的多路径路由与频谱分配算法。在保证组播实时性传输的前提下,开展了基于多路径路由策略和层图法的路由与频谱分配研究,提出了一种基于网络编码组播的多路径路由与频谱分配算法。该算法采用一种辅助层图的方法,在频谱连续性约束和时延约束下,解决基于网络编码的弹性组播光网络中组播业务的路由频谱分配。仿真结果表明,在大多数随机网络中,变化不同的仿真参数,提出的基于网络编码组播的多路径路由与频谱分配算法(NCMC-MRSA)在采用业务频谱请求均衡策略时,具有比其他算法更高的频谱利用率。随着组播平均接收端数目或随机网络规模(n>30)的增加,提出的NCMC-MRSA算法的频谱利用率高出对比算法21.63%,且大规模网络中性能优势更明显。此外,仿真还评估了不同业务排序策略对算法性能的影响。(2)面向混合类型业务的基于网络编码的弹性组播光网络的高效承载算法。考虑实际光网络中不同传输类型业务混合存在,该创新点主要面向混合类型业务,开展了基于网络编码的弹性组播光网络的高效承载问题的研究,建立了一种考虑时延约束和最大传输距离约束的数学优化模型,提出了一种考虑网络编码的自适应路由与层图法的频谱分配算法。针对不同传输类型的请求业务,该算法可以自适应地选择不同的实时路由策略。仿真结果表明,在随机网络中,随着业务平均接收端数目或随机网络规模的增加,提出的基于网络编码的自适应路由与层图法的频谱分配算法(NCAR-LGSA)较对比算法的频谱利用率平均提升了约21.72%;在随机网络中,当采用不同路由机制时,NCAR-LGSA的频谱利用率性能优于对比算法,且平均提升了 23.53%,且在真实网络中的性能优势更明显。此外,还评估了并行传输路径数目对算法性能的影响。(3)基于网络编码组播的可靠路由与频谱分配算法。当网络发生故障时,为保障承载数据量巨大的光网络正常通信,开展了面向实际光网络中混合类型业务的可靠路由与频谱分配算法研究。本文建立了一种数学模型详细表述该问题,提出了一种基于网络编码组播的可靠多路径路由与频谱分配算法,高效的解决模型问题。提出的算法解决了基于网络编码的弹性组播光网络的可靠路由与频谱分配问题,针对不同类型业务自适应的建立可靠传输结构,为工作路由结构建立专享独立的保护备份结构。此外,网络编码节点通过对信息的编码,具有对信息加密的天然保护功能,一定程度上提高了信息传输的可靠性。仿真结果表明,当变化不同的仿真参数时,对比其他比较算法,本文提出的可靠多路径路由与频谱分配算法在处理各种比例的混合类型业务时,频谱资源利用率有效提升。更多还原

【Abstract】 According to a variety of emerging high bandwidth of multicast services,the current optical networks provided with the limited spectrum resource are undergoing the serious shortage of optical resources.We mainly deal with this problem from two perspectives of optimizing the optical network architecture and improving the spectrum resource utilization.Due to that the network coding technology has the advantages of improving the network throughput,robustness and balancing the network load,the network coding based multicast capable elastic optical network is proposed by integrating the network coding technology and all-optical multicast into elastic optical network.This paper mainly investigate hybrid services efficient provisioning problem over the network coding enabled elastic optical network in a reliable and efficient way.The contributions of this doctoral dissertation are summarized as followings:(1)The research on multipath routing and spectrum allocation over the network coding enabled elastic optical networks.We proposed a multipath routing and spectrum allocation algorithm,considering the time delay constraint to ensure the real time transmission for multicast service.A layered graph approach is utilized in the proposed algoirhtm,and the routing and spectrum allocation is sloved in an integrated way.From the simulation results,compared with the benchmark algorithms,as different simulation parameters change,the proposed algorithm NCMC-MRSA utilizing the ordering policy of SRB(Spectrum Request Balancing)shows the best spectrum utlilization in most test networks.With the increase of the average number of multicast receivers or the random network size,the proposed NCMC-MRSA outperforms the MC-RSA with 21.63%improvement of spectrum utilization,and the improvement is more obvious in the large-scale network.In addition,the impact of different requests ordering policies on the performance of the proposed algorithm is also evaluated.(2)The research on the hybrid services efficient provisioning over the network coding enabled multicast capable elastic optical networks.Considering the existence of different types of services,the hybrid services efficient provisioning problem is investigated over the network coding enabled multicast capable elastic optical networks.A mathematic model is proposed with the constraints of time delay and maximal transmission distance,and a network coding enabled adaptive routing and the layered graph approach based spectrum allocation is proposed.The proposed algorithm could adaptively select different routing policies for different types of services.The simulation results show that as the average number of multicast receivers or the random network size increases,the proposed NCAR-LGSA algorithm improves the spectral efficiency by 21.72%compar~ed with other benchmark algorithms in most random networks.With different routing mechanisms,the spectrum utilization of NCAR-LGSA outperforms the benchmark algorithms with the average increase of 23.53%.Moreover,the performance advantage of NCAR-LGSA is more obvious in the real network.In addition,the impact of the number of parallel transmission paths on the performance of the algorithm is evaluated.(3)Research on reliable routing and spectrum allocation for hybrid services over network coding enabled multicast capable elastic optical networks.We mainly solve the problem of how to ensure the reliable routing and spectrum allocation for hybrid service requests in case of the failure occurs in the optical networks.An optimization mathematical model is proposed,and an efficient heuristic algorithm of reliable multipath routing and spectrum allocation algorithm for network coding based multicast is proposed.The proposed algorithm establishes an independent backup protection route adaptively for every working routing structure.In addition,network coding has the natural advantages of the information encryption,and improving the reliability transmission.From the simulation results,as different parameters change,the spectrum utilization can be improved by the proposed algorithm,compared with the benchmark algorithms.更多还原