Limited to classical ciphers? There isn't much to chose from, especially if no keyword can be given, though this is likely to keep the less skilled or uninterested from reading your messages.
If you really must transfer information you'd rather keep secret over the board to designated individuals, at least use something like Vigenere, Running Key, or VIC.
no subject
Limited to classical ciphers? There isn't much to chose from, especially if no keyword can be given, though this is likely to keep the less skilled or uninterested from reading your messages.
If you really must transfer information you'd rather keep secret over the board to designated individuals, at least use something like Vigenere, Running Key, or VIC.