Overview
FreeOTFE was initially released by Sarah Dean in 2004, and was the first open source code disk encryption system that provided a modular architecture allowing 3rd parties to implement additional algorithms if needed. Older FreeOTFE licensing required that any modification to the program be placed in the public domain. This does not conform technically to section 3 of the Open Source definition. Newer program licensing omits this condition.
This software is compatible with Linux encrypted volumes (e.g. LUKS, cryptoloop, dm-crypt), allowing data encrypted under Linux to be read (and written) freely. It was the first open source transparent disk encryption system to support Windows Vista and PDAs.
Optional two-factor authentication using smart cards and/or hardware security modules (HSMs, also termed security tokens) was introduced in v4.0, using the PKCS#11 (Cryptoki) standard developed by RSA Laboratories.
FreeOTFE also allows any number of "hidden volumes" to be created, giving plausible deniability and deniable encryption, and also has the option of encrypting full partitions or disks (but not the system partition).
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