Abstract: A method is provided for enabling a secure data exchange between a number of nodes of a network of nodes, wherein each node has identical cryptographic key pairs for encrypting the data exchange, wherein the key pairs are generated by the respective nodes themselves and automatically. The addition of nodes to a network of nodes takes place with the aid of a temporary public key which is generated by the node to be added and which has to be verified by trustworthy entities. After successful verification, the cryptographic key pair required for the data exchange is made available to the node to be added. After the new node has been added, all nodes of the network again have identical cryptographic key pairs for the encrypted data exchange.