In Snort3s beta, we added a new inspector RNA to provide network visibility. RNA analyzes passing traffic to discover hosts with filtering based on IP/port/zone. It logs information about these hosts such as protocols, applications and user agents. RNA does not generate or alter traffic on its own. The enable_logger config enables or disables sending RNA discovery events to EventManager::call_loggers. This type of event logger or reader is not implemented yet.”]
Source: https://blog.snort.org/2020/05/new-real-time-network-awareness-rna.html