Solution to October 14 challenge
The encrypted message is CJHIAURHOASFAOX. The technique used to encrypt this message was substitution, using a keyword of SECURITY.
First, write out the alphabet with the keyword first, followed by the remaining letters:
Now write the original alphabet underneath the crypto alphabet:
Now look up each letter of the encrypted message in the crypto alphabet, and write down the corresponding letter from the original alphabet.
The decrypted message is CONFIDENTIALITY