一种基于Layer 2 Trigger的移动IPv6快速切换方案的研究及实现

Research and Implementation of Mobile IPv6 Fast Handoff Based on Layer 2 Triggers

基本移动IPv6的切换时延很大,不能满足语音、视频等实时业务的要求。为此,IETF制定了快速移动IPv6草案,但是该草案在基于IEEE 802.11b/a协议的无线局域网中很难实现。在该草案基础上,本文提出了一种基于Layer2 Trigger的移动IPv6快速切换方案,利用链路层信号和快速RA机制有效地减少了切换时延。我们在基于网络处理器的路由器和Linux主机上实现了此方案。测试结果表明,本方案具有较低的切换时延;另外,由于隧道操作由硬件高速实现,因此切换前后的端对端时延抖动很小。

Because of high latency handoff, Mobile ipv6 can't meet demands for real-time services such as VoIP, video. For this, IETF proposed fast Mobile IPv6 draft. However, it is difficult to implement the draft in IEEE 802. 11b/a WLAN environment. In this paper, we propose a new low latency handoff method based on the draft, where link layer trigger signal and fast RA are jointly used to decrease handoff delay. We also implement the method by using access router based on network processor and Linux machines. Finally, experiment results show that the system can achieve low latency handoff and low fluctuate of end to end latency.