Computer data is really a series of bits (binary data that can take on two values 0/1, false/true, off/on). Bits are usually given as a series of ones and zeroes (binary). Octal (0-7), or base 8, can also be used to represent three bits. Hexadecimal (or hex for short, 0-9a-f), or base 16, can be used to represent four bits so fewer characters are needed and makes a binary number a little more manageable for people to look at. We call eight bits a byte (or octet) and some old timers may call four bits a nibble (or nybble). Another encoding is called base64. It uses 64 characters which you can look up if interested. Base64 is used to encode binary data so it is more printable or portable (like for sending in email), not to keep data confidential. Another encoding that is used more rarely is base32. Base32 uses 32 characters (letters (case insensitive) and the numbers 2-7).
The C.I.A. triad of Confidentiality, Integrity and Availability are the foundation of information security. Data should only be available to those that have the right to see it (confidentiality), data should be kept from tampered with (integrity) and data should be available when required by those with rights to read/write it. This cache will concentrate on confidentiality. Basically we need a way to send a message (cleartext) in a secure way (ciphertext) so the recipient can decode/decrypt, but others that may see it in transit or in storage cannot obtain the original message.
Compression is a way to encode data so it takes up less space. Are there any caches that use compression as part of a puzzle? That may be interesting. Compression provides no confidentiality. When doing both compression and encryption the compression step should be done first then encryption.
One way to send hidden messages is to hide the message in some image. This is known as steganography. There are many ways of doing so and won’t be covered further in this description. Substitution ciphers were an early way to hide messages. One letter is substituted for another. There are many variations of this including the Caesar cipher (ROT13 which we use all the time in Geocaching is a simple variation of this), polyalphabetic ciphers (including Vigenere) and others. Cryptograms are an example of this form of historical encryption. Substitution ciphers where one just needs to know the algorithm used are not strong at all (provides no real confidentiality). Ciphers with keys (like the Vigenere ciphers) offer some more strength and the longer the key the more secure in general. For more on substitution ciphers see Wikipedia. Many of these ciphers only work with letters while other characters remain the same. There are other ciphers that can encode characters other than letters as well.
Several stronger symmetric encryption algorithms have been developed and use a variety of operations (substitutions, transpositions, operations such as XOR (using XOR for a puzzle cache would be interesting, but this puzzle does not use it)) and key lengths. DES was once the standard, and used a 56 bit key, but it was broken and no longer considered secure. Triple-DES (3DES) uses three 56 bit keys and is fairly strong as it can have the equivalent of a 168 bit key. Today AES with a variety of key lengths (256 bit being common) and others are used to provide confidentiality of data. One issue is how we do key exchange between the two sides. The ciphertext for this cache does not make use of any strong encryption. Remember the key is to keep the data confidential from those that should not be able to view it. This cache page does protect the confidential data with a key (or passphrase) so you will need to figure out what that is and keep it confidential as well.
There are several caches in the area that make use of early forms of encryption. Being familiar with some of those would help in obtaining the coordinates for this cache. There is an excellent cache by captnkirk17 (The Cache of Wolfenstien Enigma (GC3YYTTM)) that makes use of the German Enigma machine used during WWII. Other caches that make use of Enigma in the area are “6 X 6 Challenge - One Crazy Busy Day” (GC48TNN) by Traditional Bill and “History of Cryptography: A Lesson in World History” (GC5802Z;now archived) by ivorybilledbirder. This cache does not make use of Enigma though. However, GC5802Z is an excellent puzzle cache and covers several encodings and early cryptography and some of the parts in it would help in finding the coordinates for this cache. Did you know there was a Barbie typewriter that also could be used for secret messages? See http://www.cryptomuseum.com/crypto/mehano/barbie/ for more on that. Wonder if there are any caches that use one of the Barbie ciphers which are more examples of substitution ciphers (this cache does not).
MikeOtt’s “The Dark Side” (GC47TX8) is a tough cache and this cache may have some similarities in some ways, but hopefully it’s not too far on the dark side (not trying to be difficult, just want to protect the confidential data with a key and several steps). This cache may be tougher than “The Dark Side”, but also may be more straightforward. Hopefully there aren’t too many red herrings in this description and there may even be some helpful herrings sprinkled in. Some of Joe Wessels recent puzzle caches in the Dover area are also good examples of cryptography history and one of those (or a variation of one of them) may even help in solving one of the parts needed for this puzzle. Waypointed has some good puzzle caches using ciphers in the northern part of Delaware and one of those will definitely help in solving one of the parts of this cache. Traditional Bill also has some great puzzles in his challenge caches at the WMA DoD Pond in New Jersey along the Delaware River and one (or more) of those would help in solving part(s) of this puzzle.
Enough rambling it is now time to get to the puzzle so you can get the coordinates for this cache. There are five or six steps (Waypointed may call them puzzle processes) you will need to perform to get to the plaintext. Some of them are just encodings. Two of the steps in the middle provide some confidentiality, but only one of those requires a key so that is what is being relied on to keep this data confidential. The last encoding that was done on the data was just to make it more printable so that should be a good hint as to how to get started decoding. Some of the steps give clues on what to do at the next step. Everything you should need to do is either mentioned above or used in one of the puzzle caches referenced above.
Here’s the ciphertext (remember to keep the final data confidential once you decrypt it).
diMieHx3cSJwJHcpfn5wJ318cSlxeHx7eSkjIiUmIXApfXMnfiUkeyR4dSklfiMidiMieHx3cSJwJHd7dnEpJ311cX
0oeHwidykjJCUmIXApfXN7fiV9In1+dXolfiN0diMieHx3cSJXP0sgOz5LIDkyIEY7M0YgNz8+Oz4gSTpDPDNB
Rjk/O2kgc2xfWyAhbGBbIF1dXSAhbGhbIH5sIlsgJGx9WyAkbHNbICpselsgK2xxWyAqbHtYLEZENiB6Nko2
NSAnOjg2PzZDNi4=
A geochecker shouldn’t be necessary as the coordinates of the cache will be clear once all the decoding/decrypting is complete. However, if you want to check and have proof that you solved this puzzle here is a Certitude link:
Update April 4, 2021. The location of the cache has been moved. The puzzle has not been changed. To obtain the location of the cache enter your solution into Certitude using the below link:
You can validate your puzzle solution with certitude.
Congrats to JohnnyKay on being the first certified solver of this puzzle and to Martin Mitchell on being the second.
Congrats to Martin Mitchell for earning the FTF.