Techniques are provided for initializing, maintaining, updating and recovering secure operation within an integrated system. The techniques, which employ a data access control function within the integrated system, include authenticating by a current level of software a next level of software within an integrated system. The authenticating occurs before control is passed to the next level of software. Further, an ability of the next level of software to modify an operational characteristic of the integrated system can be selectively limited via the data access control function. Techniques are also provided for initializing secure operation of the integrated system, for migrating data encrypted using a first key set to data encrypted using a second key set, for updating software and keys within the integrated system, and for recovering integrated system functionality following a trigger event.