A method of encrypting data using a first key and multiple encryption keys at least in part based on the first key. The method includes encoding the data into a redundant representation by distributing the information content of the data among a number of groups, each group being associated with a respective encryption key of the multiple encryption keys, each encryption key being associated with at least one group, the redundant representation allowing recovery of the data in the absence of the groups associated with the at least one of the multiple encryption keys, and encrypting each group by the respective associated encryption key.