COMPUTER-IMPLEMENTED METHOD FOR PROVIDING CRYPTOGRAPHIC KEYS FOR SIGNING DATA, SIGNATURE MODULE, METHOD FOR SIGNING DATA, AND METHOD FOR AUTHENTICATED COMMUNICATION

Various teachings of the present disclosure include methods for providing cryptographic keys for signing data. The method may include: providing a plurality of keys as leaves of a hash tree structure having at least one first hash tree; evaluating a requirement criterion for a requirement for additional keys and, if the requirement criterion is satisfied, generating a plurality of additional keys available as leaves of a further hash tree; and integrating the further hash tree into the hash tree structure so a respective root of the further hash tree is signed with a leaf of the hash tree structure. A number of hash trees of the hash tree structure is not predetermined.