To my Sweet Babboo
Basic Encryption Techniques and Love Professions
Kelly Burchell-Reyes
Contributor
Tired of waiting for JAC Secrets to post about your crush? Talking face-to-face is risky, and notes can be compromised…but not if they’re encoded.
Try the Caesar cipher by shifting the alphabet used by a given value. While the normal alphabet reads: ABCDEFGHIJKLMNOPQRSTUVWXYZ, one shifted by 3 starts on the third letter: CDEFGHIJKLMNOPQRSTUVWXYZAB. The word “VALENTINE” then reads “YDOHQWLGH.” Your crush can decode your message without knowing the number of shifts by the frequency with which each letter is used. An experiment at Cornell University showed that 12.02% of a 40,000 word sample consisted of the letter E, followed by 9.10% T, and 8.12% A; certain letters appear more frequently in the English language than others.
Your nosy friends could probably solve it too, so employ a polyalphabetic cipher, which requires multiple shifts indicated by a code word.
Say your code word is LOVE and your message is WILLYOUGOOUTWITHME. Shift the alphabet so that it starts on the first letter of the code word, L, and find the letter corresponding to W (the first letter of your message). Your alphabet is LMNOPQRSTUVWXYZABCDEFGHIJK, and the first encoded letter is H. For the second letter of the message, use the second letter of the code word’s Caesar cipher. Repeat the key word until your entire message is encoded as IXHQKD LAD QY IXPM YT. This cipher levels the letter frequencies, since the Caesar ciphers used cycle with the code word.
Not convinced that only your crush will know your true feelings? The one-time pad nearly ensures unpredictability. Randomly reorder the numbers 1 through 26. This sequence is the list of shifts that your beloved will use to decode your secret message. If you have 25-21-7-8-14-13-23-5-12-16-17-22-24-18-20-1-19-3-2-9-10-11-6-4-15-26, do a Caesar cipher with a shift of 25 for the first letter of your message, 21 for the second, 7 for the third, and so on.
A Caesar cipher yields 26 possible results for a given message and can be cracked with brute force. The one time pad creates 26^n combinations, where n is the number of letters in your message, since each letter is independently shifted by a random number. Now no one –not even your paramour– will decode your message!