JBO Giova Cipher
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Project Status: Release date: 21.03.2005 See the bigger picture. |
The purpose of the Giova Cipher is to secure text and messages using classical cryptographic methods. What all ciphers (except a One Time Pad) have in common is that ultimately, they are breakable. The issue is the amount of time it would take to break them and whether such time would be well spent. Some modern methods of encryption rely on large numbers which (so far) cannot be factored for security. Most traditional ciphers have a finite number of solutions ... consider a cipher system which uses an alphabetic key (any sequence of letters and of any length) to perform polyalphabetic substitution against a random table of cipher character pairs and you have the basis of the Giova Cipher.
The programme provides tabbed pages into which plaintext, or ciphertext, may be typed or loaded from suitable text files. Once a key has been entered, the user may encrypt or decrypt the desired text. When text is present on the ciphertext page, it is possible to generate a bar graph showing the frequency analysis of the ciphertext.
For amounts of text of one kilobyte or more, the distribution is usually below 6% for all characters (assuming a key which is not very repetitious). It is possible to use randomly generated keys equal in length to the plaintext, thus enabling Giova to operate as a One Time Pad cipher. Even with shorter and more user-friendly keys, patterns in ciphertext are not helpful to anyone attempting to analyse the cipher.
When decrypting a piece of ciphertext, even though the key is not encrypted into the text, the Giova programme is aware of whether the result is the correct plaintext or not. If the incorrect key is used, or if the ciphertext is not an example of Giova encryption, then output to the plain text page will be the message "Incorrect key or source data".
For programme specific help, visit the Giova help page.
