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Sharky's Vigenere Cipher

Sharky's Vigenere Cipher
This page is for amusement only. Instructions are given below this form. instructions: Enter the string to encrypt or decrypt in the Input field (you may copy and paste it from another text editor). On most computers: To copy: Highlight text, press Ctrl-C; To paste: Position cursor, press Ctrl-V. explanation: Vigenere coding is one of the most ancient forms of cryptography. Choose a key that is as long as the plaintext message. Unfortunately, these steps take all the fun out of the Vigenere cipher. Vigenere ciphers with moderate keys are appropriate for situations that do not require failproof security. We hope you enjoy this simple JavaScript-based implementation. Related:  Codes and CiphersCiphers & PuzzlesEncoder & Decoder

Keyed Caesar One variation to the standard Caesar cipher is when the alphabet is "keyed" by using a word. In the traditional variety, one could write the alphabet on two strips and just match up the strips after sliding the bottom strip to the left or right. To encode, you would find a letter in the top row and substitute it for the letter in the bottom row. For a keyed version, one would not use a standard alphabet, but would first write a word (omitting duplicated letters) and then write the remaining letters of the alphabet. For the example below, I used a key of "" and you will see that the period is removed because it is not a letter. You will also notice the second "m" is not included because there was an m already and you can't have duplicates. This encoder will let you specify the key word that is used at the beginning of the alphabet and will also let you shift the keyed alphabet around, just like a normal Caesar cipher. This is your encoded or decoded text:

GC1M2NP A Lesson in Ciphers # 1 (Unknown Cache) in Missouri, United States created by TripCyclone This cache series is designed to give you an introduction to the world of ciphers. It will not cover every type of cipher out there, instead focusing on a small variety of different ciphers. Hopefully, you will walk away from solving this series with a new set of puzzle solving skills. And maybe, just maybe, you'll be able to go to that puzzle that's always bothered you and begin to see it with a new pair of eyes. I have designed this series such that you will not be able to solve them all in one swipe. Cryptography is defined as the practice and study of hiding information. For your first lesson, we'll use a cipher that I am certain ALL OF YOU have used already. abeguguveglrvtugqrterrfsvsglsbhecbvaggjbbarguerr jrfgavarglsbheqrterrfguveglguerrcbvagmrebsviravar You are looking for a small lock 'n lock container.

Playfair Cipher The Playfair cipher encrypts pairs of letters (digraphs), instead of single letters. This is significantly harder to break since the frequency analysis used for simple substitution ciphers is considerably more difficult. Memorization of the keyword and 4 simple rules is all that is required to create the 5 by 5 table and use the cipher. The Playfair cipher uses a 5 by 5 table containing a key word or phrase. To generate the table, one would first fill in the spaces of the table with the letters of the keyword (dropping any duplicate letters), then fill the remaining spaces with the rest of the letters of the alphabet in order (to reduce the alphabet to fit you can either omit "Q" or replace "J" with "I"). In the example to the right, the keyword is "keyword". To encrypt a message, one would break the message into groups of 2 letters. If both letters are the same, add an X between them. To decipher, ignore rule 1. Source: Wikipedia Table of Contents

Cryptography When I wrote my first book, Fermat’s Last Theorem, I made a passing reference to the mathematics of cryptography. Although I did not know it at the time, this was the start of a major interest in the history and science of codes and code breaking, which has resulted in a 400-page book on the subject, an adaptation of the book for teenagers, a 5-part TV series, numerous talks and lectures, the purchase of an Enigma cipher machine and the development of an interactive crypto CD-ROM. In the Crypto Corner, you will find details about my book on cryptography (The Code Book), information about my TV series based on the book (The Science of Secrecy) and you can explore the Black Chamber, which is an interactive encryption and codebreaking section. You will also find a section about the Cipher Challenge, there are some cryptograms (coded messages) for you to try and crack, a free downloadable CD-ROM version of The Code Book, and a quick Q&A based on the questions I am most often asked.

MP3Stego When looking at the steganographic tools available on the Net, it occurred to me that nothing had been done to hide information in MP3 files, that is sound tracks compressed using the MPEG Audio Layer III format. There is a growing interest world-wide in MP3 or indeed WMA files because they offer near-CD quality at compression ratio of 11 to 1 (128 kilobits per second). This gives a very good opportunity for information hiding. Although WMA has better quality in general, I did not have access to code and only an implementation for MP3 is provided as a proof of concept. MP3Stego will hide information in MP3 files during the compression process. The data is first compressed, encrypted and then hidden in the MP3 bit stream. The hiding process takes place at the heart of the Layer III encoding process namely in the inner_loop. We have discussed earlier the power of parity for information hiding.

Polyalphabetic Substitution Ciphers Introduction The monoalphabetic (simple) substitution cipher uses only one replacement scheme for all letters of the plain text. Polyalphabetic ciphers use more than one replacement scheme. The Vigenere Cipher Given a letter of the plain text and one letter of the key word, the following table is used for encryption: The letter of the key word is located in the first row and the plain text letter is located in the first column. For decryption, the same table may be used in a different way: From the key letter in the first row trace down until you find the cipher text letter. There are three possibilities to use the keyword. Beaufort cipher The only difference to the Vigenere cipher is the use of the table: Locate the plain text letter in the first column and trace in the row to the key letter. Beaufort / Vigenere Variant Cipher For this variant of the Beaufort cipher, the role of the key and plain text letters are exchanged. Gronsfeld Cipher Polyalphabetic Substitution Cipher GROMARK Cipher

Download Enigma Simulator This software is an exact simulation of the 3-rotor Wehrmacht (Heer and Luftwaffe) Enigma, the 3-rotor Kriegsmarine M3, also called Funkschlussel M, and the famous 4-rotor Kriegmarine M4 Enigma cipher machine, used during World War II from 1939 until 1945. The sim has a very authentic feeling with its hands-on approach: you can select between the three models, actually lift out and insert different rotors, adjust their ring setting and set up the plugboard. The internal wiring of all rotors is identical to those that were used by the Wehrmacht and Kriegsmarine. This simulator is therefore fully compatible with the various real Enigma models and you can decrypt authentic wartime messages or encrypt and decrypt your own messages. The program comes with a very complete 22 page helpfile, containing the manual, some original messages, the history of Enigma and all technical details of the machine. Check out the Enigma Sim Manual to discover all the nuts and bolts of the software. Screenshots

Home - “For me the magic moment came on page 2 where the green picture could mean any of three things. I identified the picture almost at once but could not see in which of the three directions it might go. And I knew that I had to find out!” “This should come with a warning label on it. ...It's highly additive. I've put it down with good intentions of getting back to life and work. “I took it to Rome with me and sought inspiration in the Forum.... ................. aaaagh, there's no escaping the clutches of the Runes!” “It took three pages before I was fully sold on this. “What I have enjoyed is the step-by-step developments of the first few pages leading into the greater challenges as you realise that there is more to each puzzle than you were first led to think - and the buzz of discovery when you realise how it actually works.” ”This is one of the most complex puzzles I have ever encountered. “I’m totally intrigued with this puzzle. You have a great adventure before you.