一种IP网络友好的Overlay路由机制

Underlay-friendly Overlay routing mechanism for IP networks

在现存的多层路由中,上层Overlay网络在路由决策时通常对底层的IP网络性能和状态缺乏有效的协调和感知,致使上层Overlay路由和底层IP路由常常处于非协同、非优化工作状态,产生大量路由抖动和次优路由。为解决这些问题,提出了一种底层IP网络友好的Overlay路由机制,其基本思路为:增加Overlay网络的层感知能力,减少路由抖动,增加Overlay路由的稳定性。Overlay网络根据底层IP网络的节点跳数、链路带宽、丢包率等反映底层IP网络性能的信息作出路由决策。实际网络中,通过调整Overlay网络的链路代价,有效控制Overlay网络的路由决策。仿真结果表明,与传统双重路由(dual routing)相比,此IP网络友好Overlay路由机制在减少Overlay网络路由抖动、降低Overlay网络路径代价膨胀、提高Overlay网络故障恢复成功率和满足Overlay业务需求等方面有优势。

Existent Overlay networks are not IP network-aware enough.The Overlay routing is usually lack of aware of the IP network＇s performance and status.So the Overlay network appears sub-optimal routing and has route flaps that have seriously affected the Overlay network applications＇ performance.This paper proposed an IP network-friendly Overlay routing mechanism.The basic idea was： enhance the Overlay network＇s ability of lay awareness and flexibility.Overlay network routes based on the IP network＇s information（e.g.： number of route hops,link bandwidth and packet loss rate）.Changing the Overlay network＇s link cost was useful to control the Overlay routing.The simulation results show that： compared to the traditional dual routing,this IP network-friendly Overlay routing mechanism has advantages in reducing the path cost inflation and route flaps,increasing the success rate of recovery,meeting the need of Overlay applications.