Responding to Network Failures at Data-plane Speeds with Network Programmability

Measurement studies show that equipment failures happen quite frequently and pose a challenge to reliable network operation. Quickly recovering from failures is critical to meeting service guarantees. Traditional routing protocols, due to being executed in a distributed fashion and involving multiple devices in a network, require non-negligible time to recompute routes upon failures. SDN with OpenFlow simplifies route recomputation, but the time to compute and install alternative forwarding entries can still result in significant packet loss. Existing fast failover mechanisms cannot handle all types of failure and do not guarantee the use of the best paths. In this paper, we present FELIX, an approach for failure recovery that reroutes around failures at data plane timescales. Felix works by efficiently pre-computing tactics to handle failure scenarios that can be quickly activated in the data plane in response to failures. Our evaluation shows that our approach can recover from failures up to three orders of magnitude faster than existing SDN approaches.