【作者】 李彬；

【导师】 顾畹仪；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2010， 博士

【摘要】 为了适应网络高速化及业务动态化的发展要求,近年来关于网络生存性和保护效率的研究越来越得到广泛的关注。预配置环(P圈,p-cycle)保护技术有效地结合了格状光网络的效率和环网快速保护倒换的优点,能够在满足网络生存性的条件下极大程度地提高网络的保护资源利用效率。同时,自动交换光网络(ASON)目前被普遍认为是下一代传送网络控制的核心技术,在ASON网络中,生存性研究一直是个备受关注的课题,它对保障网络正常运行、保护和快速恢复受损业务具有重要意义。因此在ASON网络中提供P圈的支持和应用就显得尤为重要。在国家八六三计划项目和国家自然科学基金项目的支持下,作者对P圈技术进行了深入和广泛的调研工作,并针对该技术的关键问题进行理论研究和模拟仿真。在从事P圈保护技术研究工作的期间,形成了一套完整的关于P圈保护技术发展及应用的体系结构,并提出一些具有创新性的成果,本博士学位论文的主要工作和创新点包括以下几个方面：1.完善P圈的配置模型及相关理论工作,在P圈资源配置阶段提出新型的加权评价标准,进行资源优选配置。为多种应用场景及故障环境下P圈的应用提供了解决方案和优化算法。2.提出一种基于OPNET Modeler框架的新型P圈保护节点模型,并将该模型引入ASON Simulator仿真软件。在该模型的基础上完成非对称网络环境、混合故障模型、动态业务计算、分布式配置协议等方面的扩展和研究,通过ASON Simulator的仿真为本文的研究和理论提供强有力的数据支撑。3.提出一种针对非对称业务模型的优化P圈解决方案,创新性地将业务进行分解,在搜索并配置单方向P圈时不仅参考网络中各链路的工作容量,还综合考虑网络中各链路上工作容量在两个方向上的分布情况。给出了非对称业务环境下的P圈配置理论模型和可实用化的启发式算法,填补了P圈在非对称网络环境下资源配置方面的空缺。4.区分不同故障类型,单链路故障、节点／链路混合故障进行优化配置。特别地针对节点故障提出了一种基于两跳转发的保护方法,该方法有效地改善了节点环绕P圈的效率问题。提出邻接增补圈、弦接增补圈、相交增补圈的概念并应用于节点故障分类中,为后人继续研究提供良好的划分依据。5.设计了一套基于ASON控制平面的自动化配置和重构协议,提出针对P圈集中式配置方式和改进的分布式配置方式的实现方案。借鉴分布式协议的思想,将泛洪操作用于辅助完成P圈配置,并对其开销及降低开销的方法展开了深入的研究。同时,在以前学者所设计的分布式协议DCPC的基础上,提出一种简单而又有效的动态P圈重构方法,并在ASON Simulator上进行性能仿真。更多还原

【Abstract】 With the rapid development of high-speed network and the requirement of service dynamics, the network survivability and protection efficiency have gained more and more attentions in recent years.The preconfigured cycle (p-cycle) can improve the network performance due to their ability to provide mesh-like efficiency and ring-like speed, which can provide much more flexibility for survivability of optical network. At the same time, the Automatic Switched Optical Networks (ASON) is regarded as the primary candidate for the controlling techniques of next generation optical networks.The survivability is always an attainable issue in ASON as it is more important for the guarantee of network operator and can provide fast restorability. With the support of Hi-Tech Research and Development Program and National Natural Science Foundation of China, the author takes wide and deep investigations on the p-cycle protection technology and takes simulations and theoretical research on the key techniques for p-cycle.The main contribution and innovation of this dissertation are described as follows:1.The theory of p-cycle model and configuration is presented under different network scenario for application as different scenarios always require different criterions.New criterions algorithms are presented for several p-cycle applications under different kinds of faults.2. A p-cycle protection model is presented under the platform of OPNET modeler, and it has been successfully added to the ASON Simulator tools.Several studies such as the asymmetric network applications, multiple failure model,dynamic traffic computation, and distributed protocol for p-cycle deployment are extended to support the analysis of the proposed approach. 3.Optimized solution of the p-cycle configuration under asymmetric network has been proposed based on the knowledge of the working capacity on each link of both directions.The mathematics model is studied to reinforce the theory studies of configuration under asymmetric network, and a practical heuristical algorithm is proposed for p-cycle configuration.4.Different approaches for candidate p-cycle election are proposed for different failure types,i.e.,single-span failure,hybrid failure.Also a two-hop tranversing method is proposed to solve the efficiency problem of the node-encircling p-cycle.The concept of the adjacent supplement cycle, chord supplement cycle and interconnected cycle are given for future researches.5.Automatic configuration and reconfiguration protocol for p-cycle application in ASON network is studied based on the previous research DCPC.The distributed flooding operation is utilized to help p-cycle configuration, and also the overhead reduction approach is studied.Besides, centric configuration and distributed configurations are compared the p-cycle configurations.To verify the performance, the results are presented in ASON Simulator.更多还原