The IEC 62439 series is applicable to high-availability automation networks based on the ISO/IEC/IEEE 8802-3 (IEEE 802.3) Ethernet technology. This part of the IEC 62439 series specifies a redundancy protocol that is based on the duplication of the network@ the redundancy protocol being executed within the end nodes@ as opposed to a redundancy protocol built in the switches. Fast error detection is provided by two beacon nodes@ the switchover decision is taken in every node individually. The crossnetwork connection capability enables singly attached end nodes to be connected on either of the two networks.