Incremental Network Configuration Verification

ABSTRACTNetwork configurations are constantly changing, and each change poses a risk of catastrophic network outages. Consequently, the networking community has put significant effort into developing and optimizing configuration verifiers. However, we observe existing configuration verifiers still have a significant drawback: they are not optimized for configuration changes. That is, they always check a snapshot of network configuration from scratch, even though the configuration often changes slightly since the last verification. In this paper, we demonstrate the benefits, opportunities, and challenges of incremental network configuration verification (INCV). We also demonstrate the feasibility of INCV by introducing RealConfig, an incremental configuration verifier that can check configuration changes within one second.