Public folder replication in Microsoft Exchange Server is a mail-based, multimaster system. In a mail-based system, all changes are sent to the replica servers in mail messages. In multimaster systems, any changes in public folder contents are propagated to all other replicas of that folder on other servers, rather than channeled through a specified master server. Folder hierarchy changes are sent to all public folder servers.
Replication is configured by an administrator through the Microsoft Exchange Server Administrator program. Per-folder replication schedules, which override the server’s replication schedule, can also be configured.
At the time of a scheduled replication, the information store on a server collects all changes since the last replication. It then packs the changes into one or more specially formatted mail messages and sends them to all servers that have replicas for those folders.
Objects in information stores have a property that indicates the order in which changes occurred. This property is used to report replication status. While changes are normally propagated from each server to all the others, a single server can request the replication status from another server, and then request that all changes made since a given change number be sent.
When replicated folder information is received, the receiving server checks for conflicts in the hierarchy and the contents of replicated folders.
Access control lists (ACLs) are part of the design of a folder, and as such are replicated. They have no effect on content replication. For more information about access control lists, see About Access Control Lists.