中文摘要：

DRSVP改进型算法虽然在不影响带宽使用的情况下改进了DRSVP机制的业务流断线率，但是它只降低了高优先级业务流的断线率，而没有考虑下层业务流．针对DRSVP改进型算法的不足，提出了HLDRSVP．该机制可以在保护高优先级业务流的同时，最大可能地保护低优先级业务流．分析与仿真结果表明，HLDRSVP具有优越的性能，能够处理不同优先级的业务流，并使各优先级被拒绝业务流数目都达到最小．

英文摘要：

Improved dynamic resource reservation protocol（DRSVP） as an enhanced version of DRSVP, improves the flow dropping probability of DRSVP without affecting the bandwidth utilization but it only considers high priority flows. A new flow rejection algorithm HLDRSVP （from high to low DRSVP） was proposed to solve the problem of improved DRSVP. HLDRSVP could protect high priority flows, and at the same time protect low priority flows as possible as it could. Results of analysis and simulation experiments showed that HLDRSVP could make system get higher performance. It had excellent ability to deal with flows of different priority, and reject the minimum required number of flows per class.