PowerExchange on the source platform reads the restart tokens from the CDEP for each source included in the session. The first time a session is run with a new application name, an entry for it will be automatically created in the CDEP if it does not already exist.

If the application name already exists in the CDEP, PowerExchange will use the appropriate restart tokens to commence extraction from the change stream. Which restart tokens are used depends upon the extraction type (SL or RS) and whether new tokens have been supplied by DTLUAPPL since the last run. If new tokens have been supplied by DTLUAPPL, then those tokens will be used regardless of the extraction type.

If there are sources included that have newer restart points, they will not be provided any records from the change stream until their restart points have been reached. This prevents sources from being passed records that they processed in the previous extraction run.

After a session completes successfully, PowerExchange updates the CDEP with the ending restart tokens.