The protocols IEC 60870-5-101 (serial) and IEC 60870-5-104 (IP-based) are standardized communication protocols widely used in telecontrol technology, particularly for SCADA systems in utility companies such as electricity and water suppliers. They are employed to transmit data between control centers (masters) and remote stations (e.g., RTUs or PLCs) and are highly suitable for integration into TETRA data radio networks due to their efficiency and reliability.

IEC 60870-5-101 (IEC-101)

A serial protocol developed for communication over point-to-point or multipoint connections. It is particularly well-suited for environments with limited bandwidth, as is commonly found in TETRA networks.

It enables cyclic polling, spontaneous data transmission (unsolicited events), and event-driven alarms. The compressed data transmission of IEC-101 minimizes network load.

IEC 60870-5-104 (IEC-104)

An extension of IEC 101, utilizing IP-based communication over TCP/IP. It is optimized for networks with higher bandwidth but also operates efficiently in TETRA networks with packet data channels (PDCH).

IEC-104 uses TCP for reliable data transmission with built-in error correction and retransmission mechanisms and also supports cyclic and spontaneous data transmission as well as event-driven alarms. Additionally, it offers higher efficiency with larger data volumes compared to IEC 101, as there are no limitations on serial data rates.