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CCC#5 - Rivest Shamir Adleman Mystery Cache

This cache has been archived.

crumlin: Cachen er nu nedlagt og boksen fjernet. Den indeholdt stadig den oprindelige logbog fra maj 2005!
Tak for alle de positive logninger, der er kommet i tidens løb.

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Hidden : 6/19/2005
Difficulty:
4.5 out of 5
Terrain:
2 out of 5

Size: Size:   regular (regular)

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Geocache Description:

Crumlin Cipher Cache #5

Koordinaterne i denne serie af cacher er ikke koordinaterne på selve cacheboksen, men på en bekvem parkeringsplads i nærheden. For at finde cachen skal man dechifrere en kodet meddelelse hvor den resulterende tekst er på engelsk. Det kan også blive nødvendigt at søge visse informationer på internettet. Da disse informationer næsten udelukkende findes på engelsk, så er man nødt til at kunne læse og forstå engelsk. Resten af cachebeskrivelsen er på engelsk, men man kan få en oversættelse ved henvendelse til cacheejeren.

This is a Mystery/Puzzle cache. The coordinates of this cache are not the coordinates of the cachebox, but they will lead you to a convenient parking area.

The cachebox is a 2 liter container hidden in “Teglstrup Hegn”. It contains a logbook, a pencil, a FFC and some trading items.

Ever since the birth of computers, they have been used to “scramble” messages. One major problem is the key distribution. The key has to be exchanged using a channel that cannot be intercepted, which often means that people have to meet in private before they can begin to send enciphered messages to each other.

In 1977 Ronald Rivest, Adi Shamir and Leonard Adleman invented an asymmetric cipher, the RSA cipher, that requires one key to encipher a message and another to decipher it. The process cannot be reversed. The receiver must generate a key-pair and publish one of them (the public key) for others to use when enciphering messages to him. His other key (the private key) is the only one that can decipher the messages he receives. The sender only needs the receiver's public key to send messages - but if he has his own key-pair, the two of them can send messages to each other that nobody else can read. And they don't even have to meet in private to exchange keys.

The ciphertext below is enciphered using the public key (8597418486969457657, 179) from a key-pair. The Puzzle is to decipher it with the private key in order to get the plaintext leading to the cache. The Mystery is how to find the key. There is a rather simple mathematical relationship between the public and the private key, but it will take a computer some time to find it. Unless you can crack the key, you will have to look for clues in other caches. Look here for hint to the next cache in the series.

Ciphertext: 3316317221402312260


You can check your answers for this puzzle on Geochecker.com.

Thanks to Simon Singh for inspiring this series of caches.

Additional Hints (Decrypt)

Ng gur onfr bs ynetr fcehpr

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)