Batfish

Digital Twins Enable Pre-Deployment Testing and Post-Change Control in Complex Multi-Vendor Networks

UserGate and Hadal Project experts presented a joint approach at Saint HighLoad++ that combines physical labs, emulation, and simulation into a single lifecycle for validating network changes. The method addresses recurring failures such as IPsec tunnel outages after routine software updates that pass vendor checks yet break branch connectivity. Three complexity sources—multi-vendor environments, historical configuration debt, and continuous dynamic updates—are mitigated by maintaining an always-current network model. Physical laboratories provide hardware-level accuracy for critical devices, while uInfraTwin emulation allows rapid, repeatable testing of configuration scenarios with traffic generators. Simulation tools including Batfish, Hadal, Forward Networks, and IP Fabric deliver end-to-end reachability analysis across tens of thousands of nodes without sending test traffic on production networks. The integrated digital twin continuously updates from live infrastructure, feeds selected segments into safe test environments, and verifies policy compliance after deployment.