Detour Planning for Fast and Reliable Failure Recovery in SDN with OpenState

TL;DR

This paper introduces a SDN failure recovery scheme using OpenState, enabling instant, controller-independent protection with precomputed backup paths, ensuring zero packet loss even during controller outages.

Contribution

It proposes a novel SDN failure recovery method based on OpenState, allowing autonomous, rapid rerouting without controller intervention, unlike traditional approaches.

Findings

Guarantees instantaneous recovery times.

Achieves zero packet-loss after failure detection.

Operates independently of controller reachability.

Abstract

A reliable and scalable mechanism to provide protection against a link or node failure has additional requirements in the context of SDN and OpenFlow. Not only it has to minimize the load on the controller, but it must be able to react even when the controller is unreachable. In this paper we present a protection scheme based on precomputed backup paths and inspired by MPLS crankback routing, that guarantees instantaneous recovery times and aims at zero packet-loss after failure detection, regardless of controller reachability, even when OpenFlow's "fast-failover" feature cannot be used. The proposed mechanism is based on OpenState, an OpenFlow extension that allows a programmer to specify how forwarding rules should autonomously adapt in a stateful fashion, reducing the need to rely on remote controllers. We present the scheme as well as two different formulations for the computation of backup paths.