
Bykov noted transparent firewalls have largely appeared to be invisible to all of the other systems. This invisibility creates substantial challenges for network management. “We needed to update our model to support something that isn’t inherently visible from the troubleshooting perspective,” he said.
The technical approach to solving this challenge leverages IP Fabric’s networking expertise. When asked how they detect devices that are purposely designed to be stealthy, Bykov said that it’s his team’s experience as network practitioners that makes the difference. That and the fact that the firewall, whether it’s transparent or not, still shows up somewhere in a network ARP (address resolution protocol) table.
During the discovery process, IP Fabric connects to all infrastructure devices using SSH and API credentials to collect configuration and operational data from firewalls. This includes interface states, bridge-group, membership, access control lists (ACLs) and inspection rules. Drawing on this data, IP Fabric analyzes bridge group configurations, as well as all interfaces assigned to the same bridge group, to identify interfaces that pass traffic transparently.