Digital data blocks are encrypted, each data block that is to be encrypted being associated with a time reference. A value of an initialization vector Vi and an encryption key K are defined. Then, a counter C is obtained for each data block to be encoded, by combining the time reference and the value of the initialization vector. A series of binary encryption elements is obtained via an encryption function taking the encryption key K and counter C as input parameters. The data block is then encrypted by combining it with the series of binary encryption elements.