Sørensen's paper "describes the work done to add hot standby replication functionality to the Apache Derby Database Management System."

The problem statement for the thesis was as follows:

In addition to the physical log in Derby, write a logical log to a Neighbor Node which acts as a hot standby for the database, ensuring replication and improving the availability of Derby. The hot standby database will redo the logical log records received. If the primary Derby database crashes the Hot Standby will become primary and accept connections. Finally, when the crashed Derby recovers it will synchronize itself with the now active primary and then reenter hot standby mode.