DiskCryptor - is the only truly free solution, provided under GNU General Public License (GPLv3), which offers encryption of all disk partitions, including the system one. The main criterion for an open software, is the availability of its source code under one of the open source licenses. The only analogous to DiskCryptor software, with the open source code, is the TrueCrypt. However, because of the restrictive license under which the TrueCrypt is provided, - the TrueCrypt Collective License, TrueCrypt cannot be classified as a truly free software, as it places limits for developers, on the use and modification of its source code. The other similar in function to DiskCryptor programs, are fully proprietary ones, which makes them unacceptable to use for protection of a confidential data.
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