The ability to track changes in the database resides within the Jet database engine. As its name implies, every action executed by Microsoft Jet in one replica is tracked and recorded in preparation for its transmission to other replicas. Both data and design changes are replicated. The main replication services, including the creation of replicable databases and replica synchronization are included in the files MSRepl35.dll, MSRclr35.dll, and MSJet35.dll.