Better than LEDs for convenience.

An IEEE standard for local and metropolitan area networks–Port-Based Network Access Control. IEEE 802 LANs are deployed in networks that convey or provide access to critical data, that support mission ...

All-in-one ICS/SCADA hacking, red teaming, malware analysis, detection, and lab architecture cheat sheet - ridpath/SCADA-OT-CheatSheet-Advanced-ICS-Hacking-Playbook ...

Passive network monitoring sensors deployed on SPAN/TAP ports at OT network boundaries OT intrusion detection system (Dragos Platform, Nozomi Guardian, Claroty xDome, or Suricata with OT rulesets) ...