Methods and apparatuses enable synchronization of shared data in a cluster of ranked repositories. A publisher repository issues a change message indicating a change in shared data. A subscriber repository receives the change message and determines whether the change message is previously known to the subscriber repository. If the message is previously known, the subscriber repository terminates the change message. If the message is not previously known, the subscriber repository republishes or sends a change message in response to receiving the change message. The republished message can be republished in a variety of ways based on the characteristics of the change message and characteristics of the subscriber repository.