【作者】 汪海鹰；

【导师】 曾华燊；

【作者基本信息】 西南交通大学 ， 计算机应用技术， 2010， 博士

【摘要】 随着Internet的广泛应用,多媒体数据逐渐成为网络应用数据的主体,网络数据源从“人”和“计算机”扩展到智能化的各类“物”,而网络应用正呈现出分布式、虚拟化和面向服务的趋势。所有这些变化使30多年前在低通信速率和高误码率通信条件下,为文本数据传输而设计的Internet面临着高速交换、服务质量保障、安全／可靠／可用性和移动性方面的严峻挑战,进而呼唤下一代Internet(NGI-Next Generation Internet)的诞生。经历了10多年“IPv6就是NGI”的失败尝试之后,学术界的主流研究终于在2006年全球网络创新环境组织GENI提出了“有30多年历史的Internet已经成为制约网络发展的主要因素”之后走出误区,认识到“解决下一代网络的关键在于研究新的体系结构”。西南交通大学四川省网络通信技术重点实验室在本世纪之初就率先开展了NGI体系结构的研究,2003年发表其首个NGI体系结构研究成果—"3D-EMAN",2004年发表了“单层用户数据交换平台体系结构”(SUPA),并先后提出了用“开放式网络应用服务参考模型”替代OSI/RM和“骨干通信子网优先,外延次之”的NGI研发策略。SUPA以NGI骨干通信子网为对象,用带外信令思想将多层结构的“信控与管理平台”和“用户数据交换平台”相分离,进而在DWDM之上,以实验室提出的“面向以太网的物理帧时槽交换技术”(EPFTS)为基础实现单层结构的通信子网交换平台,为接入骨干网的用户数据(帧、分组或任何形式的应用数据)提供安全、服务质量可保障、高速高效和面向连接的服务。本博士论文反映的研究工作以SUPANET的EPFTS交换平台上的资源管理与基于可保障服务质量的组播技术为对象,重点研究了传输与交换资源的分配机制和基于QoS的组播路由技术。本论文的主要贡献如下：(1)在SUPANET网络资源管理技术研究方面,提出了针对区分服务的基于业务流类型的配额分配模型QAM(Quota Allocation Model)和能根据用户服务质量差别动态分配资源的机制—基于EPFTS的动态配额分配机制DQAE(Dynamic Quota Allocation based on EPFTS)。(2)将服务质量和资源预留结合起来,以作者提出的“服务质量偏离函数”ξ(Q,θ)作为动态调整资源的重要度量值,进而设计出基于配额余量的动态调整算法(RQ-DAA-Residual Quota based Dynamic Adjustment Algorithm)。经理论分析和数学推导证明了该算法的稳定性和有效性；仿真实验结果也表明配额的动态分配可以为用户提供较好的服务质量保证,更为有效地利用网络资源。进一步研究表明结合SUPA虚隧道技术,DQAE机制可为用户提供更好的端到端的服务质量保障。(3)研究了组播技术,针对组播技术的特点和EPFTS的特性,为SUPANET设计了合理的组播机制。改进了网络拓扑图的生成算法,为组播路由的实验奠定了基础。(4)根据SUPANET中的组播树特性,提出了面向服务质量的度约束组播路由算法—基于物理帧时槽交换的度约束组播路由算法MRDP(Multicast Routing Degree-constrained algorithm based on EPFTS),并为组播的2种模式：稀疏和稠密,分别设计了相应的度约束算法MRDP-1和MRDP-2。2种算法在各自适合的网络环境下,将组播树的时延性能和节点的转发能力均衡分布作为目标函数进行优化,可达到建树代价较小和负载均衡分布的目的。本文研究工作表明基于EPFTS技术的网络资源管理和组播路由技术可以保障用户的服务质量,增加网络的可靠性。本文的相关研究成果对于SUPANET的构建具有参考意义和实际应用价值,特别是对提高网络的可靠性、可用性具有重要的应用价值。更多还原

【Abstract】 With proliferation of Internet in user number and in applications, network application data have evolved from texts to multimedia, data resources have expanded from humanbeings and computers to variety of intelligent physical objects; and distribution, virtualization, and service-orientation have become the main trend in network application development. All these have forced the Internet, built more than 30 years ago, to face with severe challenges in high-speed switching, insurance of quality of service (QoS), security/reliability/feasibility, and in mobility, which in turn call for Next Generation Internet (NGI). Unsuccessful attempt to build NGI merely with IPv6, majority of academic communities had realized that the crux of the problem for NGI lies in network architecture after Global Environment for Network Innovation (GENI) declared in 2006 that the Internet built more than 30 years ago became the main constraint for network development.The Sichuan Network Communication Technology Key Laboratory at Southwest Jiaotong University pioneered a research project on NGI architecture at the beginning of this century. It published its first NGI architecture, called 3D-EMAN for MANs in 2003 and SUPA (Single-layer User-data switching Platform Architecture) for backbone subnetworks in 2004. Later, it appeals to replace the OSI/RM with the new Open Network Application Service/Reference Model (ONAS/RM) and promotes a new development strategy called Backbone Substrate First, Outwards Extension Second (BSF-OES). With a re-clarified out-of-band signaling concept, the SUPA enables to separate the backbone subnetworks into two platforms:a single-layer User-data switching Platform (U-Platform) and a multi-layer S&M-Platform for Signaling and Management. The U-Platform, built on top of DWDM with a novel swiching technique called Ethernet-oriented Physical Frame Timeslot Switching (EPFTS), can provide a connection-oriented service for user-data of access networks (frames, packets, or application traffic) with secured, QoS insured, high-efficient and high-speed switching characteristics.The work presented in this thesis focuses on resource management in U-platform of SUPANET and on multicast technologies with an emphasis on assignment and tuning of transmission and switching resources and on QoS insured multicasting technologies. Main contributions of this thesis are as follows:First, network resource management technology is analysed, and quota allocation model (QAM) is proposed baesd on the type of traffic. Dynamic quota allocation based on EPFTS (DQAE) is also proposed which can dynamic allocation resources with different QoS acquirement.Second, quality of service deviation functionε(Q,θ) as an important measure which dynamic adjust quota is proposed combined QoS with resource reservation. Residual quota based dynamic adjustment algorithm (RQ-DAA) is also designed. The theoretical analysis and mathematical derivation prove that the algorithm have stability and effectiveness performance. Simulation results show that the dynamic allocation of quota can provide users with better QoS and more efficient use of network resources. Further studies show that combining SUPA virtual tunneling, DQAE mechanism can provide better QoS performance for end-users.Third, this thesis investigates a novel aspect of multicast techniques in SUPANET based on EPFTS features. Author also improved a network topology generation algorithm for multicast routing experimental.Fourth, multicast routing degree-constrained techniques based on EPFTS (MRDP) are designed which include two algorithms:MRDP-1 and MRDP-2. Those QoS-oriented algorithms have been proposed to cope with two application enviorments:sparse graph and dense graph. Algorithms can achieve the low cost building multicat tree and load balancing purposes using the delay performance and the ability of a balanced distribution of forwarding nodes in multicast tree as the target function.This dissertation shows that the techniques of network resource management and multicast routing technology based on EPFTS can guarantee the QoS of users and increase network reliability. The related research achievement of the thesis is practical to be implemented and has a reference value in SUPANET. Especially research results have important application value in improving reliability, availability in SUPANET.更多还原