In the left side of this illustration, there are four disk drives with 1 disk labelled as the "Hub" and the other three disks labelled as "Satellites." The Hub is in the center of the illustration with bidirectional arrows going from the Hub to each one of the three Satellites. This indicates that Oracle Streams supports the capture of data changes at the primary database or downstream at a replica database, enabling you to build this hub and spoke network configuration that supports three replica databases.
On the right side of the illustration, there are two disk drives that are being maintained by Oracle Data Guard to provide additional protection for the Hub and one of the Satellites. This is indicated by two arrows in the center of the illustration, with "Oracle Data Guard" in the center of each arrow that points to the site with the standby Hub and standby Satellite.
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