The IEC 62439 series of standards is applicable to high-availability automation networks based on the ISO/IEC 8802‑3:2000 (Ethernet) technology.

This part of the IEC 62439 series specifies a redundancy protocol that is based on a ring topology, in which the redundancy protocol is executed at the end nodes, as opposed to being built into the switches. Each node detects link failure and link establishment using media-sensing technologies, and shares the link information with the other nodes, to guarantee fast connectivity recovery times. The nodes have equal RRP network management functions.