A Replication Agent is required for every database that stores primary data or initiates replicated functions. A Replication Agent reads the data server transaction log to detect changes to primary data and executions of replicated stored procedures. The transaction log provides a reliable source of information about primary data modifications because it contains records of committed, recoverable transactions.
Chapter 5, “Introduction to Replication Agents” describes the Replication Agents for data servers other than Adaptive Server. Replication Agents for some non-Sybase data servers—such as DB2, Microsoft SQL Server, and Oracle—are available from Sybase.