中文摘要：

提出了一种适用于层次移动IPv6（HMIPv6）网络的呼叫准入控制（call admission control，简称CAC）方案，该方案以过载率和系统容量为限制，根据网络中主机的移动特性和呼叫特性，自适应地计算出区域中各小区的理想呼叫数，使系统效益最大化，通过建立HMIPv6网络下的Markov模型，计算出达到理想呼叫数的CAC阈值，并将其作为是否接纳新呼叫的判断依据，仿真实验分析了影响最优区域范围的因素，为设计动态微移动管理方案提供了依据，它指出：随着呼叫在小区之间的切换率和平均持续时间的增加，最优区域范围增加而理想呼叫数减少；随着过载率限制的放宽，新呼叫阻塞率（call blocking probability，简称CBP）减小而切换中断率（handoff dropping probability，简称HDP）增大，最后，在与移动IP预留（mobile IP reservation，简称MIR）方案的性能对比中发现：在2000个仿真时段内，所提方案的CBP均值和HDP均值均比MIR的CBP均值和HDP均值要低，实现了优化。

英文摘要：

A call admission control （CAC） scheme used in hierarchical mobile IPv6 （HMIPv6） network is proposed, which solves the ideal call number of each cell adaptively to maximize system＇s profits, under the restriction of system＇s overload probability and capacity and in terms of hosts＇ mobility characteristics and call characteristics. The CAC threshold of each cell used in making decisions of accepting or rejecting a new call by network is solved by establishing a Markov model in HMIPv6 network, which can make system＇s call number up to the ideal value. Simulation analyzes the factors affecting the optimal regional size, providing a reference for designing a dynamic regional mobility management scheme. The simulation analyses reveal that with the increase of calls＇ handoff probability and average duration time, the optimal regional size increases while the regional ideal call number decreases; and with the restriction of overload probability relaxes, the new call blocking probability （CBP） comes down while the handoff dropping probability （HDP） goes up. Finally, a performance comparison result between the proposed scheme and the mobile IP reservation （MIR） scheme demonstrates that the average values of CBP and HDP in the proposed scheme are lower than those in MIR during 2000 simulation intervals, which means the optimization is realized.