针对微观移动协议现有切换机制的缺点，提出了主动切换机制，利用移动预测技术，在切换发生前预测移动主机将要切换的下一蜂窝以及切换的时刻，为移动主机预先建立新路径；为了保证主动切换机制的实现，提出了一个适用于主动切换机制并易于实现的移动预测算法；同时还提出了主动切换过程中分组丢失和重复避免方法；通过理论分析和系统仿真的方法对主动切换机制进行了性能评价，结果表明主动切换机制以较小的代价获得了可观的性能改善。

Aiming at the disadvantages of current handoff mechanisms in micro-mobility protocols, active handoff mechanism is proposed. This mechanism takes advantage of mobility prediction technique to predict the next cell a mobile host will handoff to and the handoff time before the handoff really happens and establish the new path for the mobile host in advance. To guarantee the implementation of active handoff mechanism, a mobility prediction algorithm is proposed which is suitable for active handoff mechanism and easy to implement. Meanwhile the methods to avoid packet loss and packet duplication in active handoff procedure are proposed. The performance of active handoff mechanism is evaluated through theoretical analysis and system simulation. The result shows that active handoff mechanism obtains considerable performance improvement with less cost.