Multi cloud transactional storage for availability and security

A system, comprising:

• one or more hardware processors;
• and
• a computer readable storage medium having stored therein instructions which are executable by the one or more hardware processors to perform operations comprising:
• exposing a block storage which is distributed across a group of multiple sites;
• receiving a primary write request that identifies data to be stored;
• separating data identified in the primary write request into ‘n’ data pieces, where ‘n’≥2;
• encoding the ‘n’ data pieces by creating multiple new blocks of data, and each of the new blocks of data comprises a different respective combination of the ‘n’ data pieces, where the data pieces are encoded in such a way that when a sufficient number, but fewer than all, of the multiple new blocks of data are retrieved, the data identified in the write request is recoverable with a key that was used to encode the ‘n’ data pieces;
• and
• writing the new blocks of data to different respective sites of the group, where writing of the new blocks of data is performed in conjunction with a plurality of secondary write requests, each of which corresponds to one of the new blocks of data.