Sub-Second Path Restoration for Stateful-based Segment Routing

Abstract

Stateful-based segment routing enables a controller-independent and a distributed segment routing on SDN networks by exploiting the state keeping mechanism of stateful switches. However, the routing path recovery is considerably slow since it is bounded by the minimum timeout value of state keeping, which is ≥ 1 seconds. This property disables stateful-based segment routing to deliver a carrier-grade network recovery (≤ 50 ms) using fast rerouting-based path protection to minimize packet loss after a link failure. In this paper, we enable fast network recovery for stateful-based segment routing using path restoration, as an alternative to path protection scheme. We proposed a BFD-triggered proactive link testing and multiple segment advertisement channels (ProMAC) that quickly restore the routing path in decentralized fashion at forwarding plane speed. Based on the experiment results, it can guarantee a carrier-grade network recovery (sub 50 ms) in low latency networks. In averages, the packet loss is minimized in more than ten times compared to a typical stateful-based segment routing. In a high latency network, the method can restore the network in approximately one Round Trip Time (RTT) of the network at forwarding plane speed, which is significantly smaller than one second.