Examples
One well-known example of a system based on optimistic replication is the CVS version control system, or any other version control system which uses the copy-modify-merge paradigm. CVS covers each of the five elements:
- Operation submission: Users edit local versions of files.
- Propagation: Users manually pull updates from a central server, or push changes out once the user feels they are ready.
- Scheduling: Operations are scheduled in the order that they are received by the central server.
- Conflict resolution: When a user pushes to or pulls from the central repository, any conflicts will be flagged for that user to fix manually.
- Commitment: Once the central server accepts the changes which a user pushes, they are permanently committed.
A special case of replication is synchronization, where there are only two replicas. For example, personal digital assistants (PDAs) allow users to edit data either on the PDA or a computer, and then to merge these two datasets together. Note, however, that replication is a broader problem than synchronization, since there may be more than two replicas.
Other examples include:
- Usenet, and other systems which use the Thomas Write Rule (See Rfc677)
- Multi-master database replication
- The Coda distributed filesystem
- Operational Transformation, a theoretical framework for group editing
- Peer-to-peer wikis
- The Bayou distributed database
- IceCube
Read more about this topic: Optimistic Replication
Famous quotes containing the word examples:
“In the examples that I here bring in of what I have [read], heard, done or said, I have refrained from daring to alter even the smallest and most indifferent circumstances. My conscience falsifies not an iota; for my knowledge I cannot answer.”
—Michel de Montaigne (1533–1592)
“Histories are more full of examples of the fidelity of dogs than of friends.”
—Alexander Pope (1688–1744)
“No rules exist, and examples are simply life-savers answering the appeals of rules making vain attempts to exist.”
—André Breton (1896–1966)