【作者】 马飞；

【导师】 宋俊德；

【作者基本信息】 北京邮电大学 ， 电路与系统， 2010， 博士

【摘要】 现代服务业是国家发展的战略性新兴行业,是当前国民经济与社会发展的新增长点,而信息通信技术正是现代服务业的发展引擎和支撑平台。国家“十一五”科技支撑计划重大项目明确提出要建立现代服务业的共性技术支撑体系与应用示范环境,这对现代服务业的应用支撑平台提出了新的需求与挑战,而异构网络融合正是建立应用支撑平台的前提与基础,也是未来网络技术发展的必然趋势。本文采用了理论分析、实验仿真、示范平台开发相结合的研究方法,针对融合网络系统架构与接口、能力适配、智能切换、接纳控制与负载均衡等关键性问题及其相关理论展开深入的讨论。本论文的创新点主要体现在以下几个方面：1)根据现代服务业的应用需求,本文提出了基于适配层的异构网络融合系统架构,并对Parlay X API标准中的业务接口进行扩展,定义了相应的标准化业务接口,并将此架构与接口应用于现代服务业应用示范平台的开发与实现。网络适配层位于接入网络层与业务层之间,从数据、管理、控制三个平面实现对异构网络能力的抽象,向下屏蔽底层网络的异构复杂性,支持电信网、互联网、卫星等网络接入方式,向上层应用提供统一开放的标准化接口,支持现代服务业的应用。2)针对异构网络中存在多种终端、多种接入的特性及应用需求,本文提出了一种新的用户／终端管理机制与能力适配算法,实现以用户为中心的个人移动性。用户／终端管理机制是针对用户及其拥有的多个终端建立“用户—终端—网络”的多重关联机制,以实现对用户及终端的管理。能力适配算法是通过网络测量的方法采集用户、终端及网络的相关信息,综合考虑用户偏好、业务需求、网络状态等因素,利用网络／终端选择算法为用户选择当前最佳网络及最佳匹配终端。仿真表明该算法能够对用户及终端进行有效地管理,可以根据业务类型为用户选择最佳可用网络及匹配终端。3)根据现代服务业对业务连续性的需求,本文提出了基于能力适配的智能切换机制,将能力适配过程中为用户选定的目标网络及终端,与当前的接入网络及终端进行比较,以判定切换的类型,并根据各切换的不同信令交互流程,实现网络切换、终端切换以及网络／终端联合切换功能,从而实现了跨网络、跨终端的智能切换过程。本文对相应方案的切换性能进行仿真并对平台性能进行测试,其结果表明该切换机制能够有效地提高业务的QoS性能,保证业务的连续性。4)现代服务业的应用包含多种不同的业务类型,本文针对不同的业务分别定义了相应的效用函数,并设置了不同呼叫类型的优先级,提出了基于效用的接纳控制与负载均衡机制,通过预测系统的效用增益,根据系统效用最大的原则,对新呼叫和切换呼叫的准入控制功能,并将过载网络中的负载转移到轻载网络,使得网络间的负载达到均衡分布状态。仿真结果表明该机制能够提高异构系统的总效用,降低网络的呼阻率,从而保证融合系统的QoS性能。本论文的研究内容作为科技支撑计划项目中的部分研究成果,对相应的关键技术进行了仿真与分析,并将其应用于示范平台的开发与实现。在此基础上还建立了应用示范基地,为现代服务业的进一步发展与应用提供了可靠的支撑示范平台及其技术依据。更多还原

【Abstract】 Modern service industry is not only a new strategic industry but also a new growth point for the development of national economic and social development. And then information and communication technology is the engine and platform of modern service industry. The goals of national "Eleventh Five-Year Plan" projects are to create a common technical support system and application demonstration environments. Thus, the requirements put forward new demands and challenges for the supporting platform of modern service industry. In this dissertation, a research method is adopted based on theoretical analysis, experimental simulation and plat-form software development to discuss some key issues, which include system ar-chitecture and interface, capability adaptation, intelligent handoff, admission con-trol and load balancing and other related technologies. The innovations of this dis-sertation are concluded as follow.Firstly, according to the applications of modern service industry, a new system architecture is proposed based on the network adaptation layer for heterogeneous networks, and a set of standard interfaces are defined by modifying Parlay X APIs and raising new service interfaces. Furthermore, the architecture and the interfaces have been applied to setup the platform for modern service industry. Network Ad-aptation Layer realizes the network capability abstraction from data plane, man-agement plane and control plane, which is lied between Access Network Layer and Service Layer. It is used to shield the complexity of the underlying heterogeneous network downward to support the telecom networks, the Internet, satellite and other network access technologies, and to expose the standard service interfaces upward to realize the applications of modern service industry.Secondly, in order to meet the needs of multi-networks and multi-terminals, a new management method and a capability adaptation algorithm are proposed to achieve user-center personal mobility. The management method builds a "user- terminal-network" of multiple correlation mechanism to manage the users and ter-minals especially when one user has several terminals. Capability adaptation algo-rithm can collect users, terminals and network information by network measure-ment, and select the optimal network and the ideal terminal for the user considering the user preferences, service QoS parameters, network status and other factors. Simulations show that that the algorithm can effectively manage the users and ter-minals and select the best available network and terminal.Thirdly, according to the requirements of service continuity for modern ser-vice industry, an intelligent handoff algorithm based on capability adaptation is proposed to realize the seamless handoff across terminals and networks. The objec-tive network and terminal selected by capability adaptation module are compared with the current ones to determine the handoff type. And then the handoff proc-esses across networks and terminals are implemented based different handoff sig-naling flow, which includes network vertical handoff, terminal handoff and joint network and terminal handoff. Simulations and platform tests are conducted ac-cording to the corresponding handoff functions, which can ensure the service con-tinuities and user’s QoS performance.Fourthly, because the application of modern service industry includes a vari-ety of different service types, utility functions are defined respectively for different services, and call priorities are defined according to different call types such as a new service call and a handoff call. Therefore, an admission control algorithm and a load balancing mechanism are propped based on the pre-estimation of utility gain, which respectively achieve admission control for the new call and handoff call and to make heterogeneous networks balanced on traffic load. Simulations shows that the can improve the total system utility, drop the call blocking probability and en-sure the QoS performance of the business.In sum, the contents of this dissertation are discussed as a part of the modern service industry project, and simulations and analysis are taken to illustrate the key technical schemes and algorithms, which have been applied to the development and implementation of demonstration platform. The demonstration base is estab-lished to provide an effective instruction for the further development of modern service industry.更多还原