Data Pump shuts down during the backup - you can configure it to restart automatically after it has completed.
If you are configuring a schedule from the MDP Administrator it will do that automatically, as it creates a Scheduled Task that runs BackupRestore.exe with a command line.
FYI, here are the command line arguments.
Usage: BackupRestore Specifies the maximum time to wait for system shutdown.
-nostartup Specifies that MDP is not to be restarted after the operation completes.
-q[uiet] Operates in non-interactive lights out mode.
-? Shows this usage message
The timeout spedifies the maximum amount of time (in hh:mm:ss form) to wait for system shutdown to occur before commencing the backup or restore
operation. The default timeout is 5 minutes.
When -q[uiet] is specified the backup or restore operation proceeds without user interaction and the result is reported in the system event log.
If you are doing it interactively, there is a checkbox which is enabled by default that will force MDP to restart after a backup or restore.