Network node for generating an authentication indicator, comprising: a communication interface configured to receive an operating parameter of a further network node via a communication network, wherein the operating parameter of the further network node represents an operating state of the further network node; a memory configured to store a reference operating parameter of the further network node, wherein the reference operating parameter represents a reference operating state of the further network node; and a processor configured to compare the operating parameter with the reference operating parameter in order to obtain a comparison result, and to generate the authentication indicator on the basis of the comparison result, wherein the authentication indicator indicates a successful authentication of the further network node by the network node or a failed authentication of the further network node by the network node, wherein the communication interface is configured to receive a plurality of further authentication indicators via the communication network, and wherein the processor is configured to determine a number of successful authentications of the further network node on the basis of the authentication indicator and the plurality of further authentication indicators, and to determine a number of failed authentications of the further network node on the basis of the authentication indicator and the plurality of further authentication indicators, characterized in that the processor is configured to compare the number of successful authentications of the further network node with the number of failed authentications of the further network node, and to suppress a transmission of user data between the network node and the further network node if the number of successful authentications is less than or equal to the number of failed authentications. a communication interface configured to receive an operating parameter of a further network node via a communication network, wherein the operating parameter of the further network node represents an operating state of the further network node; a memory configured to store a reference operating parameter of the further network node, wherein the reference operating parameter represents a reference operating state of the further network node; and a processor configured to compare the operating parameter with the reference operating parameter in order to obtain a comparison result, and to generate the authentication indicator on the basis of the comparison result, wherein the authentication indicator indicates a successful authentication of the further network node by the network node or a failed authentication of the further network node by the network node, wherein the communication interface is configured to receive a plurality of further authentication indicators via the communication network, and wherein the processor is configured to determine a number of successful authentications of the further network node on the basis of the authentication indicator and the plurality of further authentication indicators, and to determine a number of failed authentications of the further network node on the basis of the authentication indicator and the plurality of further authentication indicators, characterized in that the processor is configured to compare the number of successful authentications of the further network node with the number of failed authentications of the further network node, and to suppress a transmission of user data between the network node and the further network node if the number of successful authentications is less than or equal to the number of failed authentications.