Abstract: A method of removing metadata from a database in a multimode replication system includes establishing a metadata retention period for nodes in the system as well as associating changes with nodes on the system. The system responds to an expiration of the retention period for any one node by analyzing the associated changes and nodes and determining if the change affects data shared with other nodes. If the data is shared with other nodes then the expired retention period node metadata is removed from the system. If the expired metadata retention period node does not share the changes with other nodes, the metadata is not removed. This allows any unique changes to still be entered into the database without adversely affecting other nodes.

Abstract: A synchronization framework is provided for synchronizing data groups between a server and clients that may go off-line. The framework includes a client sync provider component that interfaces to client storage in a storage format independent way, a sync agent component that collects synchronization metadata maintained by the clients and uploads and/or downloads changes to the data groups to and/or from server storage and a server sync provider component that interfaces via sync adapters to server storage independently of storage format. The framework provides default building blocks for building off-line synchronizing applications that behave according to default application synchronization scenarios, and also enables custom building blocks for custom off-line application synchronization scenarios.

Abstract: A synchronization framework is provided for synchronizing data groups between a server and clients that may go off-line. The framework includes a client sync provider component that interfaces to client storage in a storage format independent way, a sync agent component that collects synchronization metadata maintained by the clients and uploads and/or downloads changes to the data groups to and/or from server storage and a server sync provider component that interfaces via sync adapters to server storage independently of storage format. The framework provides default building blocks for building off-line synchronizing applications that behave according to default application synchronization scenarios, and also enables custom building blocks for custom off-line application synchronization scenarios.

Abstract: An efficient way is provided to represent and exchange knowledge across nodes when synchronizing between any two nodes. A first node sends a second node its knowledge, including objects and versions of those objects. The second node compares its knowledge with the knowledge of the first node, and then sends the first node any latest versions of objects of which the first node is unaware. In addition, the second node sends its knowledge to the first node. The first node then performs a similar object-by-object version comparison to determine any conflicts due to independent evolution of objects and any changes that should be sent to the second node in order to bring the objects of the second node up to date with the knowledge of the first node.