Data replication based upon a non-destructive data model

A method for replicating data at multiple devices, comprising the steps of:

• representing the history of a data object at each of first and second devices by means of a graph of atoms, where said atoms contain information pertaining to changes in the content of the data object, and said graph contains at least one parent atom having at least two descendant atoms;
• adding an atom to the atom graph at said first device when a change is made to the data object at said first device;
• updating the history of the data object at a second device by forming a new graph at said second device that is a strict superset of the of the atom graph that existed at said second device prior to said updating step, and a non-strict subset of the union of the atom graphs that existed at said first and second devices prior to said updating step, such that said atom graph can contain at least one parent atom having at least two direct descendant atoms that represent different versions of said data object;
• and
• at each of said devices, selectively designating either one of said different versions to be viewed as the representative version of said data object at that device.

A system for replicating data at multiple devices, comprising:

• a store at each of said devices, each of said stores containing replicas of a data object;
• a manager associated with each store that detects and records operations performed on the data object in the form of a graph of atoms containing at least one parent atom having at least two descendant atoms, and that updates the history of the data object by receiving atoms that are contained in a graph at one store and adding said atoms to the graph in another store by forming the mathematical union of the atom graphs at said two stores, such that said atom graph can contain at least one parent atom having at least two direct descendant atoms that represent different versions of said data object;
• and
• means for selectively designating either one of said different versions at a given store to be viewed as the representative version of said data object at the device associated with that store.