In the field of IT, and in particular to distributed data storage across a plurality of storage servers, the disclosed distributed backup method includes the following steps: dividing the data so as to obtain data blocks; determining, for each block, a particular server from the plurality of storage servers; and memorising each block in the determined server. The determination of the particular server is a function of a current time instant. It can also be a function of a private key of the user. The key is used to form a mask. The latter is offset as a function of the current time instant. Then, the offset mask and the complementary mask thereof are applied, respectively, to two server distribution tables in order to identify the servers to be used for each of the data blocks. The blocks can change servers at each new time instant.