Abstract: In view of the problem that mobile node handoffs among wireless heterogeneous networks,this paper proposes an adaptive initiative predictive vertical handoff algorithm.It adoptes a cost function which orients active application to evaluate and select available networks;and it adjusts the handoff performance time automatically considering its stable period,mobile node’s velocity and location,so mobile nodes can make handoff adjudgement adaptively.The simulation results show that the proposed algorithm can efficiently reduce handoff latency,packet loss and the counts of handoff,increase the handoff performance of the system and improve traffic QoS．

摘要： 针对移动节点在异构网络间切换性能不理想的问题,提出了一种自适应主动预测的垂直切换算法。采用一种面向当前应用程序的代价函数对可接入网络进行评估与选择;根据稳定周期、移动节点的运动速度及所处位置来自动调整切换执行时间,使移动节点能自适应地进行切换判决。仿真结果表明,该算法可以有效地减少切换延迟、分组丢失及切换次数,提高系统的切换性能,改善业务的QoS。