基于时延的移动IPv6路由优化机制

Delay-based Route Optimization Mechanism in Mobile IPv6

路由优化是基于直接路径比间接路径理想的假设,但这个假设并非一定成立,而且路由优化还会引起数据包失序,降低网络性能.提出一种基于时延的移动IPv6路由优化机制.该机制通过对RRP过程中的HoT消息和CoT消息加盖时间戳,由移动节点测量直接路径和间接路径传输时延并决定是否进行路由优化.同时,通过在间接路径发送结束标识LAST消息及计时器机制避免路由优化产生的数据包失序.最后,通过仿真实验对本机制性能进行分析.

Route optimization which is a key technology to solve the problem of triangle routing in mobile IP is based on the assumption that the direct path from a correspondent node to a mobile node is more optimal than the indirect path. However, the assumption is not always the case, and the route optimization may lead lots of packets to be out-of-sequence and degrade the performance of networks. A delay-based route optimization mechanism in mobile IPv6 is therefore proposed to solve the problem, in which the HoT and CoT messages are both stamped with the time during RRP （return routability procedure）, and whether the route optimization is to be done depends on the transmission delays obtained by measuring both the direct and indirect paths from the mobile nodes. Meanwhile, LAST message as the mark of ending is sent from indirect path with a timer scheme utilized to avoid out-of-sequence packets. A simulation was done to analyze the test data of the mechanism proposed.