The time has come to issue a warning: this entire series of caches will be archived between May 1st and October 31st, 2022.
A Cipher Series
Oded is the fifteenth in a series created for those interested in some degree in cryptology. It is recommended that one do these in alphabetical order, the entire series being Alberti (GC3TAT5), Babbage (GC3V0GV), Colossus (GC3VAFW), Doyle (GC3WTWC), Enigma (GC3X6T8), Flowers (GC41DHR), Gifford (GC6B6HE), Hammer (GC6BR6X), Information (GC6CAXY), Jabberwocky (GC6CY2J), Koblitz (GC6DFP0), Lewis (GC6DMYB), Michie (GC6E4GP), Newman (GC6ENZC), Oded (GC6FNDV), Painvin (GC6G245) and Quits (GC6GN8R). Some can be done independent of the others - this one certainly can - but, in general, information given and skills acquired in one cache will not be repeated in subsequent caches and so we suggest that they be done in order. We hasten to add that there is not necessarily any connection between the name of the cache and the type of cipher used therein.
Oded - the Name of the Cache
Since we could find no evidence of a cryptographer of note having a last name starting with “O,” we have turned to Oded - Oded Goldreich (born 1957) - who is a member of the faculty at the Weizmann Institute of Science in Israel where his areas of responsibility are mathematics and computer science. One of his varied interests is cryptography about which he has written at least two books including: Foundations of Cryptography (in two volumes) and Modern Cryptography, Probabilistic Proofs and Pseudorandomness.
Chief among the things that caught our interest in the information pertaining to Dr. Goldreich was that he is “known for ‘zero-knowledge proof.’” “What,” we said, “is that!?!?” And we suspect that most of you are in the same boat, so to speak. Initially, we did provide a little information about that topic with an illustration but it took a lot of space so we decided that it would be better to let you do your own research if you are interested. But just don’t let anyone tell you that geocaching is a matter of trivialities!!
Oded, the Cache
The Encryption Process
The “encryption process” is a straight substitution from the normal alphabet to another alphabet so that if a symbol in the cryptogram means “e” in one spot, it does everywhere else too. We did not use a “Caesar Shift” to establish the alphabet used nor did we do it at random. We treated every letter of the plain text alphabet in the same way but we won’t say how and we think it would not be easy to determine that. It is probably preferable to turn to the fact that given a large enough sample, some letters are known to appear more often than others.
The Decryption Process
Allow us to refer to two gripping short stories involving cryptograms which should be “required reading” for anyone interested in cryptography - and they make it look so easy!
In “The Adventure of the Dancing Men,” Sir Arthur Conan Doyle has Mr. Sherlock Holmes patiently explaining to Dr. Watson that
“E is the most common letter in the English alphabet and it predominates to so marked an extent that even in a short sentence one would expect to find it most often. . . . The order of the English letters after E is by no means well marked, . . . [but] speaking roughly, T, A, O, I, N, S, H, R, D and L are the numerical order in which letters occur; but T, A, O and I are very nearly abreast of each other.”
In Edgar Allan Poe’s “The Gold Bug,” the protagonist explains that
“in English, the letter which most frequently occurs is e. Afterwards, the succession runs thus: a o i d h n r s t u y c f g l m w b k p q x z. E however predominates so remarkably that an individual sentence of any length is rarely seen, in which it is not the prevailing character.”
These two assessments being somewhat different and referring to the English of other times and places, we consulted the computer and came up with information of additional assistance, perhaps. Here follows a modern rating of the letters of the English alphabet and their frequency, expressed as per cents:
e (12.7), t (9.1), a (8.2), o (7.5), i (7.0), n (6.7), s (6.3), h (6.1), r (6.0), d (4.3), l (4.0), u (2.8), c (2.8), m (2.4), w (2.4), f (2.2), y (2.0), g (2.0), p (1.9), b (1.5), v (1.0), k (0.8), x (0.2), j (0.2), q (0.1), z (0.1).
In addition, when decyphering, common pairs are th and ea. Others are: of, to, in it, is, be, as, at, so, we, he, by, or, on, do, if, me, my, up.
Common pairs of repeated letters are ss, ee, tt, ff, ll, mm and oo.
Common triplets of text are the, est, for, and, his, ent or tha.
Now that you have this information to go on, we are presenting an encyphered paragraph of text from a book we read recently which, naturally, will go uncredited. It is provided so that you will have a long enough passage that applying the above information may be done with some validity and, we hope, success. The length of the words is the same as in the plain text. You will probably not need to complete the translation of that passage!! Once you have established what you consider to be enough of the cypher alphabet, you may wish to stop and turn your attention to the cryptogram which reveals the cache co-ordinates. Or, you may find the cryptogram long enough in itself to analyze with validity. Good luck!
OMF DOZSBFLA XD LAF LQ PR QNKLZSXOF ENTFENAU JSFNOZSFD, OMLZBM X MNKF AFKFS DFFA N VXEU LAF. OMFDF SFDXEXFAO NAXPNED MNKF JLPF ULVA OL ZD NEPLDO ZAJMNABFU XA OMF QLDDXE SFJLSU XA OVL MZAUSFU PXEEXLA RFNSD, DOXEE VFNSXAB OMFXS NSPLZS WENOXAB QSLP OMF UXALDNZS NBF. OMFR BSLV DELVER QFFUXAB NEPLDO FGJEZDXKFER LA OXAR XAKFSOFYSNOFD LQ OMF PZUUR YLOOLP VXOM OMFXS OLLOMEFDD PLZOMD. OMFR JNA EXKF VFEE YFRLAU N JFAOZSR NAU BSLV OL LKFS LAF MZAUSFU TXELBSNPD, YR QNS OMF ENSBFDO QSFDMVNOFS QXDM VF MNKF. LJJNDXLANEER, N ENSBF DOZSBFLA XD JNZBMO DLPFVMFSF XA OMF JLZAOSR NAU DXG LS FXBMO WFLWEF NSF SFHZXSFU OL MLEU XO ZW QLS OMF WMLOLBSNWM.
The Cryptogram
RLZ VXEE QXAU OMF JNJMF NELAB OMF SNXE OSNXE NAU ULVA N DELWF VMXJM JNA YF DEXWWFSR NO OXPFD NO VFDO DXGOR-WEZD-FXBMOFFA UFBSFFD QLSORDXG NAU FXBMO MZAUSFU QLSORDFKFA OMLZDNAUOMD PXAZOFD NELAB VXOM ALSOM QXQOR-PXAZD-DXG UFBS AXAFOFFA NAU DXG MZAUSFU DXGOR OMLZDNAUOMD PXA.
Your Task
Decrypt the sentence and you will have the co-ordinates of the cache.
The Co-ordinates
The Co-ordinates are:
N ___ ___ ° ___ ___ . ___ ___ ___ ’ and W ___ ___ ___ ° ___ ___ . ___ ___ ___ ‘.
Comments
- Please provide your own writing utensil;
- Thanks to murfster for the container;
- Tweezers may prove to be an asset;
- Enjoy the walk;
- You are welcome to check your answer for this puzzle on GeoChecker.com.