The software is available at:
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For constructive critiques and comments I should be very grateful.The binary result of encryption can e.g. be transported as an attachment file in a normal email system (certainly also in an email system with built-in "security features"). A good symmetric end-to-end encryption of messages between two private persons can therewith be very simply realized for the users.
(For an asymmetric encryption software, see
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M. K. Shen