METHOD FOR AUTHENTICATING MESSAGES IN RESOURCE LIMITED SYSTEMS

The present invention provides a method for message authentication, in particular in case of low of transmission or storage capacities. The present invention further provides corresponding devices for generating or sending authenticated messages and for receiving or retrieving authenticated messages as well as a system comprising such devices. In an embodiment, the method may comprise (a) preparing a data block having an uncompressed length; (b) compressing the data block so that the data block has a compressed length smaller than the uncompressed length; (c) determining an available length from at least the compressed length and a maximum length of a data frame; (d) calculating a message authentication code, MAC, from at least the data block, having a MAC length not greater than the available length; and (e) creating the data frame, comprising the data block and the MAC.