User guide

To change when the memory cleaner application runs, you can use IT policies or the BlackBerry device user can turn on or turn
off the memory cleaner application in the Security options on the BlackBerry device.
You or the BlackBerry device user cannot turn off the memory cleaner application on the BlackBerry device if any of the following
conditions exist:
• You or the BlackBerry device user turns on content protection on the BlackBerry device.
• An application uses the RIM® Cryptographic API to create a private key or symmetric key.
• An application that registers with the memory cleaner application requires that memory cleaning application be turned on.
• The BlackBerry device user installs the S/MIME Support Package for BlackBerry® smartphones on the BlackBerry device
and a private key exists on the BlackBerry device.
• The BlackBerry device user installs the PGP® Support Package for BlackBerry® smartphones on the BlackBerry device and
a private key exists on the BlackBerry device.
If you or the BlackBerry device user turns on the the memory cleaner application, Java® based garbage collection process uses
the memory cleaner application automatically. The garbage collection process overwrites data that the BlackBerry device no
longer uses.
For more information about the IT policy rules that you can use to change when the memory cleaner application runs, see the
BlackBerry Enterprise Server Policy Reference Guide.
When a BlackBerry device overwrites data in the BlackBerry device memory
A BlackBerry® device continually runs the memory cleaner application during the Java® based garbage collection process to
overwrite data in the BlackBerry device memory that the BlackBerry device no longer uses.
The BlackBerry device runs the garbage collection process when any of the following conditions exist:
• You or a BlackBerry device user turns on content protection for the BlackBerry device.
• An application uses the RIM® Cryptographic API to create a private key or symmetric key.
• A third-party application turns on the garbage collection process by registering with the memory cleaner application on
the BlackBerry device. The memory cleaner application instructs applications to empty caches and to free the BlackBerry
device memory that is associated with sensitive application data that the applications no longer use.
• A BlackBerry device user installs the S/MIME Support Package for BlackBerry® smartphones on the BlackBerry device.
• A BlackBerry device user installs the PGP® Support Package for BlackBerry® smartphones on the BlackBerry device.
When the BlackBerry device runs the garbage collection process, the garbage collection process overwrites the data that the
BlackBerry device no longer uses with zeroes, periodically runs the memory cleaner application, and overwrites the memory that
the memory cleaner application frees.
Security Technical Overview
When a BlackBerry device overwrites data in the BlackBerry device memory
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