【作者】 贺攀峰；

【导师】 刘宏立；

【作者基本信息】 湖南大学 ， 电路与系统， 2004， 硕士

【摘要】 因特网技术的普及，使得人们实现了网络通信和信息共享，但基于有线方式的Internet受到空间和时间的限制，无法满足用户随时随地能够接入因特网的要求，这成为研究移动主机路由协议的驱动力。为了在移动通信网络中运用IP协议，因特网工程任务组(IETF)制定了Mobile IP协议。Mobile IP协议是一种简单可扩展的全球Internet移动解决方案，使节点在切换链路时仍可保持正在进行的通信。未来移动通信网络的两个最重要的研究问题就是宽带和无缝漫游，而移动性管理是实现网络间无缝漫游的关键难题之一。本文就移动性管理领域两个具有挑战性的问题：位置管理和位置预测分别进行了较为详尽的探讨。 文章首先主要研究了用树形网络进行位置管理的策略，该策略主要基于当前已有的位置管理策略和业界提出的组播树策略。由典型树结构引申而出的树形网络结构最利于处理移动用户漫游时位置的管理等等问题。移动节点漫游时，移动节点在漫游域逐级向上一级可行的父节点进行登记，直至发现与归属域共享的父节点。通过数学推导，对基本策略(GSM或IS-41)和该策略的开销进行了对比研究，得出在一定条件下，该策略有其可行性。 这种树形网络结构为自适应邻居发送算法的智能化提供了一个较为理想的平台。自适应邻居发送算法是为切换管理的优化而提出的一种算法，是介于目前业界在切换领域提出的单播邻居发送算法及组播发送算法之间的一种智能发送算法。之所以称“自适应”，就是结合位置预测机制，引入模糊控制策略，系统可以根据移动台越区时切换的频度以确定需要邻居单播的基站数目。经分析推导，该机制在一定条件下的确能够提高系统的QoS性能。更多还原

【Abstract】 Recent initiatives to add mobility to the Internet are being considered by emerging mobile service providers as possible Candidate Solutions for the delivery of IP (Internet Protocol) data to mobile users. To run IP on the mobile communication networks ,Mobile IP is defined by the Internet engineering task force ( IETF).The terms broadband! and seamless are the main keywords for future mobile communication systems and the mobility management is the most important problem in seamless roaming across systems .In this paper each aspects of mobility management are introduced, especially management framework and some protocols. Location management and location predictability are the challenging topics in the mobility management.Firstly, this paper proposed a scheme with tree structure to manage location information for MN. The scheme mainly bases on the location management scheme and multicast-trees scheme. On the foundation of typical tree structure, the scheme is proved to be a better location management scheme whenever a mobile node crosses the boundary of location areas quickly. During a mobile node crosses the boundary of location areas, the mobile node updates to feasible father-node until the MN and its HLR belong to the same father-node. Additionally, some formulas were derived. According to these formulas, the cost of tree location management scheme, on certain conditions, is less than the cost of the basic scheme(GSM or IS-41).At the same time, networks with tree structure have brought new ideas to the solutions of the smart for self-adaptive neighbor transmission algorithm. This algorithm is proposed to guarantee traffics QoS (quality of service) and attains smooth handoff of service traffics for MN which crosses the boundary of location areas quickly. Combining with fuzzy control algorithm and location predictability scheme, this scheme is able to decide the number of BS (base station) which needs neighbor uni-cast according to the handoff frequency of the MN. This is so called self-adaptive of this scheme. And of course, it’s derived to progress QoS greatly on certain conditions.更多还原