Receiver network component for operation in a communication network of an automation system, wherein the receiver network component is set up to receive data messages sent redundantly by transmitter network components (12A-B) of the communication network and to reject duplicates of an already received data message; wherein - the receiver network component is set up to be prompted by reception of a current data message from one of the transmitter network components (12A-B) to check said data message for whether a data message with identical useful data has already been received from another transmitter network component (12A-B), and to process a data message with a useful data content received for the first time further, and to reject as a duplicate a data message with such useful data as have already been received in an earlier data message from another transmitter network component (12A-B); characterized in that - the receiver network component is set up to perform the check on the currently received data message using a sender identifier contained in the data message, wherein - the receiver network component comprises a group information item about such transmitter network components (12A-B) as send identical, in terms of their useful data content, data messages to the receiver network component while they are operating; and - the receiver network component is set up to perform the check on the currently received data message using the sender identifier of the currently received data message and the sender identifiers of the transmitter network components (12A-B) indicated in the group information item; and wherein - the group information item contains sender identifiers of transmitter network components (12A-B) such that a sender identifier of all those transmitter network components (12A-B) that send data messages with identical useful data content to the receiver network component while they are operating is selected as a group sender identifier and the sender identifiers of all other associated transmitter network components (12A-B) are allocated to the group sender identifier. - the receiver network component is set up to be prompted by reception of a current data message from one of the transmitter network components (12A-B) to check said data message for whether a data message with identical useful data has already been received from another transmitter network component (12A-B), and to process a data message with a useful data content received for the first time further, and to reject as a duplicate a data message with such useful data as have already been received in an earlier data message from another transmitter network component (12A-B); characterized in that - the receiver network component is set up to perform the check on the currently received data message using a sender identifier contained in the data message, wherein - the receiver network component comprises a group information item about such transmitter network components (12A-B) as send identical, in terms of their useful data content, data messages to the receiver network component while they are operating; and - the receiver network component is set up to perform the check on the currently received data message using the sender identifier of the currently received data message and the sender identifiers of the transmitter network components (12A-B) indicated in the group information item; and wherein - the group information item contains sender identifiers of transmitter network components (12A-B) such that a sender identifier of all those transmitter network components (12A-B) that send data messages with identical useful data content to the receiver network component while they are operating is selected as a group sender identifier and the sender identifiers of all other associated transmitter network components (12A-B) are allocated to the group sender identifier. - the receiver network component is set up to perform the check on the currently received data message using a sender identifier contained in the data message, wherein - the receiver network component comprises a group information item about such transmitter network components (12A-B) as send identical, in terms of their useful data content, data messages to the receiver network component while they are operating; and - the receiver network component is set up to perform the check on the currently received data message using the sender identifier of the currently received data message and the sender identifiers of the transmitter network components (12A-B) indicated in the group information item; and wherein - the group information item contains sender identifiers of transmitter network components (12A-B) such that a sender identifier of all those transmitter network components (12A-B) that send data messages with identical useful data content to the receiver network component while they are operating is selected as a group sender identifier and the sender identifiers of all other associated transmitter network components (12A-B) are allocated to the group sender identifier.