The International Electrotechnical Commission 60870-5-104 (IEC-104) protocol is used in SCADA (Supervisory Control and Data Acquisition) systems and is primarily employed for communication with remote terminal units in electric power systems. IEC 60870-5-101 (IEC-101) is the specification for Serial Communications (over physical wires); whereas IEC-104 is the specification over TCP/IP communications, and as such, is the main concern for IDS (Intrusion Detection Systems). IEC 60870-6-503 or Telecontrol Application Service Element (also known as "TASE", and later "TASE 2"; or "ICCP" Inter-Control Center Communication Protocol) is an that includes the protocol specification for intra-controller communications; whereas IEC-60870 specifies the communications between control systems and remote devices (RTU-Remote Terminal Units).

This SonicWALL signature identified legitimate IEC 60870-5-104 network traffic.