Patent ID: 7685185

Claim:
A computer implemented method of synchronizing a plurality of replicas having a collection of items, the plurality of replicas including a target replica having a first interest set of items, and the plurality of replicas including a source replica having a second interest set of items, the method comprising the steps of: (a) storing representations of items that are known to the target replica in the target replica; (b) receiving a sync request from the target replica at the source replica, said request indicating versions of items known to the target replica; (c) transmitting from the source replica to the target replica at least one item-set knowledge fragment, the at least one item-set knowledge fragment indicating versions of items which are not known to the target replica; and (d) transmitting from the source replica to the target replica a notification of a changed item if a set of predetermined conditions are met, the item falling within the first interest set of the target replica prior to the change in the item, and the item not falling within the first interest set of the target replica after the change in the item.