| Description: |
"TrueCrypt is a
software system for establishing and maintaining an
on-the-fly-encrypted volume (data storage device). On-the-fly
encryption means that data are automatically encrypted or decrypted
right before they are loaded or saved, without any user
intervention. No data stored on an encrypted volume can be read
(decrypted) without using the correct password/keyfile(s) or correct
encryption keys. Entire file system is encrypted (e.g.., file names,
folder names, contents of every file, free space, meta data, etc).
Files can be copied to and from a mounted TrueCrypt volume just like
they are copied to/from any normal disk (for example, by simple
drag-and-drop operations). Files are automatically being decrypted
on-the-fly (in memory/RAM) while they are being read or copied from
an encrypted TrueCrypt volume. Similarly, files that are being
written or copied to the TrueCrypt volume are automatically being
encrypted on-the-fly (right before they are written to the disk) in
RAM. Note that this does not mean that the whole file that is to be
encrypted/decrypted must be stored in RAM before it can be
encrypted/decrypted. There are no extra memory (RAM) requirements
for TrueCrypt. For an illustration of how this is accomplished, see
the following paragraph.
Let's suppose that there is an .avi video file stored on a TrueCrypt
volume (therefore, the video file is entirely encrypted). The user
provides the correct password (and/or keyfile) and mounts (opens)
the TrueCrypt volume. When the user double clicks the icon of the
video file, the operating system launches the application associated
with the file type – typically a media player. The media player then
begins loading a small initial portion of the video file from the
TrueCrypt-encrypted volume to RAM (memory) in order to play it.
While the portion is being loaded, TrueCrypt is automatically
decrypting it (in RAM). The decrypted portion of the video (stored
in RAM) is then played by the media player. While this portion is
being played, the media player begins loading next small portion of
the video file from the TrueCrypt-encrypted volume to RAM (memory)
and the process repeats. This process is called on-the-fly
encryption/decryption and it works for all file types, not only for
video files.
Note that TrueCrypt never saves any decrypted data to a disk – it
only stores them temporarily in RAM (memory). Even when the volume
is mounted, data stored in the volume is still encrypted. When you
restart Windows or turn off your computer, the volume will be
dismounted and files stored in it will be inaccessible (and
encrypted). Even when power supply is suddenly interrupted (without
proper system shut down), files stored in the volume are
inaccessible (and encrypted). To make them accessible again, you
have to mount the volume (and provide the correct password and/or
keyfile)." |
