The "Geocaching 101" puzzles and/or hides are designed to teach some of the basics of puzzle-solving. If you are new, or a seasoned veteran, they should be informative and help you hone your skills with the many varieties of Geocache types that are out in the world today.
Geocaching 101 : The ROT13 Cipher
ROT13 (or ROT-13) is a very simple form of encryption cipher. It is a variant of a Caesar cipher (created by, or used by Julius Caesar). In it, the alphabet is written in two lines of 13 characters each and they key is where the letters of the Alphabet are offset by 13-places.
The example is as follows : all 'A's (the first letter) are replaced with 'N's (the 13th letter), all 'B's are replaced with 'O's, and so on. It can also be known as a Caesar Cipher with a shift of 13.
The ROT13 cipher offers almost no security, and can be broken very easily. Even if an adversary doesn't know a piece of ciphertext has been enciphered with the ROT13 cipher, they can still break it by assuming it is a substitution cipher and determining the key using hill-climbing. The ROT13 cipher is also an Caesar cipher with a key of 13, so breaking it as a Caesar cipher also works.
The Algorithm of ROT13
The ROT13 cipher is essentially a substitution cipher with a fixed key, if you know the cipher is ROT13, then no additional information is needed to decrypt the message. The substitution key is:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
NOPQRSTUVWXYZABCDEFGHIJKLM
To encipher a message, find the letter you wish to encipher in the top row, then replace it with the letter in the bottom row. In the example below, we encipher the message 'ATTACK AT DAWN'. The first letter we wish to encipher is 'A', which is above 'N', so the first ciphertext letter is 'N'. The next letter is 'T', which is above 'G', so that comes next. The whole message is enciphered:
ATTACK AT DAWN
NGGNPX NG QNJA
To decipher a message, the exact same procedure is followed. Find 'N' in the top row, which is 'A' in the bottom row. Continue until the whole message is deciphered.
It is widely used online in USENET forums, as well as GEOCACHING, of course.
There are also variants of the ROT13, but since there are 26-letters in the English alphabet, it has popularity based on its simplicity for gaming or simple cipher uses.
abcdefghijklmnopqrstuvwxyz
NOPQRSTUVWXYZABCDEFGHIJKLM |
| aha ↔ nun |
ant ↔ nag |
| balk ↔ onyx |
bar ↔ one |
| barf ↔ ones |
be ↔ or |
| bin ↔ ova |
ebbs ↔ roof |
| envy ↔ rail |
er ↔ re |
| errs ↔ reef |
flap ↔ sync |
| fur ↔ she |
gel ↔ try |
| gnat ↔ tang |
irk ↔ vex |
| clerk ↔ pyrex |
purely ↔ cheryl |
| PNG ↔ cat |
SHA ↔ fun |
| furby ↔ sheol |
terra ↔ green |
There are some words, that will produce another existing word, when they are treated with ROT13. The longest example in the English language is the pair of 7-letter words abjurer and nowhere; there is also the 7-letter pair chechen and purpura. Other examples of words like these are shown in the table.
The 1989 International Obfuscated C Code Contest (IOCCC) had an entry by Brian Westley. Westley's computer program can be ROT13'd or reversed and still compiles correctly. Its operation, when executed, is either to perform ROT13 encoding on, or to reverse its input.
The newsgroup alt.folklore.urban made a word—furrfu. It was the ROT13 encoding of the frequently encoded utterance "sheesh". "Furrfu" evolved in mid-1992 as a response to postings repeating urban myths on alt.folklore.urban, after some posters complained that "Sheesh!" as a response to newcomers was being overused.
ROT13 is the code used to encrypt the "Hint" on each geocache listing.
This geocoin illustrates the rotation principle:
Our Puzzle here will deal *only* with the ROT-13 cypher, much like the Geocaching Listing "Hint" space found on all Geocaching Listings.
The numbers that you will need will be spelled out using the ROT-13 cypher: Example: 1 = one, 2 = two, etc.
You should be able to solve the puzzle and you will be able to solve the puzzle based on decyphering the information.
Again, this puzzle is designed to teach you how to solve more puzzles, and think "outside the box" on some possibly more difficult ones.
Most of the information contained here is available online via normal Google search.
Have fun and we hope you've learned something today!
**Note: As with MOST Geocaching Puzzles, the geographic point on the Map is *not* the location of the final container. This is no exception with this puzzle either. Solve the puzzle to be able to find the container and sign the paper log.
The Puzzle:
Abegu Sbegl Gjb
Gjragl Rvtug qbg Frira Avar Mreb
Jrfg Mreb Rvtugl Guerr
Guvegrra qbg Gjb Gjragl Gjb
At the final, be aware of your Surroundings and the
MANY muggles around at ALL HOURS
while hunting this cache.
Physical log MUST be signed to claim the smiley
Thank You
Enjoy the fun and the hunt!