1. In a sync community that includes a plurality of replicas, wherein each replica is able to make changes to data independently of other replicas in the sync community, a method for replicating a replica in the sync community, the method comprising a first replica performing: receiving a knowledge vector from a second replica in a sync community, wherein the knowledge vector represents changes to data that the second replica is aware of; comparing the knowledge vector of the second replica with versions associated with changes in the first replica to identify changes on the first replica that are not known by the second replica; and sending the identified changes to the second replica.