The simplest methods of text encryption. Codes and ciphers

In the courtyard of the CIA building in Langley stands S-shaped copper plate with encrypted text. This is the most famous element of the sculpture "Kryptos", its authors are the sculptor James Sanborn and Ed Scheidt, the retired head of the CIA's cryptographic department. They came up with a cipher, which is difficult to solve, but quite real. At least they thought so.

As conceived by the authors, "Kryptos" personifies the process of collecting information. The Cryptos cipher is 869 characters divided into four parts. The creators assumed that the decision of the first three parts it will take about seven months, to solve the whole problem - about seven years. 23 years later, there is still no complete transcript. Cryptos is run by amateurs (there has been a group of about 1,500 people on Yahoo! since 2003) and professionals (from the CIA and the NSA) - their task is complicated by the deliberate mistakes made by Sanborn and Scheidt (partly to confuse people, partly for aesthetic reasons).
It is believed that Sanborn - only person on the planet, knowing the solution to the "Kryptos". The sculptor says that people who are obsessed with the cipher he created are calling and saying terrible things: "They call me a servant of the devil, because I have a secret that I do not share with anyone." Sanborn says that in the event of his death, the answer will surely pass to someone else, but adds that he will not be completely upset if the correct solution remains forever a mystery.

Murderer, about whom nothing is known yet, sent encrypted letters to California newspapers, promising that they would contain clues to establishing his identity. The first message of the Zodiac (August 1969) consisted of three parts and 408 characters, it was deciphered the fastest by an ordinary Californian married couple. The meaning of the letter was that killing people is much more interesting than animals, because a person is the most dangerous creature on the planet. "I will go to heaven, where those whom I have killed will become my slaves," the note read. This was the last successful attempt to decipher the Zodiac's cryptogram. The contents of a postcard with a 340-character code that arrived three months later at the San Francisco Chronicle remain a mystery. “Can you print it on the first page? I feel terribly lonely when they don’t notice me, ”the killer asked in an accompanying letter. It is this cipher that is depicted on the poster of David Fincher's film Zodiac.

A few days later, the Zodiac sent another letter in which he encrypted his name - it also remained unsolved. Then there was a letter in which the killer threatened to blow up the school bus. He attached a map and a cipher to it - with their help, it was allegedly possible to find a bomb that was planned to be used for a terrorist attack. No one coped with this cipher either, but the explosion did not occur either. Attempts to unravel the codes of the Zodiac continue. In 2011, amateur cryptographer Cory Starliper claimed to have deciphered a 340-character message and found in it a confession from Arthur Lee Allen, who was once the prime suspect in the Zodiac case but was released for lack of evidence. Many newspapers wrote about Starliper, but it quickly became clear that his method did not hold water.

Phaistos disk. It is believed that the hieroglyphic inscriptions on the Phaistos disc supposedly belong to the Minoan civilization that lived on the island of Crete. A clay disc with hieroglyphs inscribed on both sides in the form of a spiral was discovered in 1908. Experts have determined that there are 45 different hieroglyphs on the disk, and some of them are similar to signs used in the early palace period.

An 18th century shepherd's monument in Staffordshire, England. It has a strange sequence of letters DOUOSVAVVM, a code that has not been deciphered for more than 250 years. The author of this cipher is unknown, some believe that this code may be a clue left by the Knights Templar regarding the location of the Holy Grail. Many of the greatest minds have tried to decipher this code and failed, including Charles Dickens and Charles Darwin.

Linear writing. It was also found in Crete and named after the British archaeologist Arthur Evans. In 1952, Michael Ventris deciphered Linear B, which was used to encipher the Mycenaean language, the oldest known variant of Greek. But Linear A is only partially solved, while the solved fragments are written in some language unknown to science, not related to any of the known languages.

In 1933, General Wang of Shanghai, China, was given seven gold bars.. The ingots were engraved with drawings, inscriptions on Chinese and cryptograms, partly in Latin letters. Presumably, these are certificates issued by an American bank. The inscriptions in Chinese say about the deal, the amount of which exceeds 300 million US dollars.

John F. Byrne invented the Chaocipher encryption method in 1918. Byrne considered it very simple, but still difficult to decipher, and for 40 years he unsuccessfully tried to interest the American government in his invention. He even offered a reward to someone who could solve his cipher, but no one asked for the reward. Only last year his family handed over all the papers regarding the cipher to the museum, and the specialists managed to figure out his method.

Signal "Wow!"- a strong narrow-band space radio signal recorded by Dr. Jerry Eiman on August 15, 1977 while working on the Big Ear radio telescope at Ohio State University. Under this name, the Signal is imprinted in the history of the Program for the Search for Extraterrestrial Civilizations, as still undeciphered.

British mathematicians in their own way participated in the underwater battles of World War II. Halfway between Oxford and Cambridge, in the town of Milton Keynes, at the height of the war, a kind of institute was set up where Alan Turing and other famous scientists worked on breaking the code that was used in Germany to communicate with submarines. The German ciphers used an apparatus similar to a typewriter with two keyboards: one regular, the other with light bulbs. When the radio operator hit a key with her finger, the light flashed under some other letter. This letter should have been added to the encrypted version of the message. Without a single sample of the Enigma at hand, Turing was able to understand the principle of the machine and build his decoder based on logical reasoning alone. The British historian Hinsley even claimed that a breakthrough in cryptanalysis brought the end of World War II closer by two, if not four years. The exceptional role played by breaking the Enigma code in the victory over the Nazis was also referred to by Queen Elizabeth II of Great Britain when she posthumously pardoned the mathematician a few months ago. In 1952, Turing was sentenced to chemical castration for homosexuality, after which the scientist committed suicide.

Jotunvillur. There are only a few thousand runic inscriptions: orders of magnitude fewer texts than classical antiquity left behind. And then we are usually talking about short fragmentary phrases on planks or on stones. Jonas Nordby, a graduate student in linguistics at the University of Oslo, focused on the 80 ciphers: if you try to read them as they are, they come out nonsense. Nine, as it turned out, use a fairly simple, by the standards of modern cryptography, algorithm - the author of the study calls it Jotunvillur: the rune is replaced by the one whose name (“the name of the rune”) ends with the desired letter. Why so secretive, it is clear in some cases. One of the inscriptions on the tablets read by Nordby reads "Kiss me." Considering that both the addressee and the sender of the message had to at least be able to read, then both were probably men.

During the Second World War, the British army often used pigeons to transmit encrypted messages. In 2012, a resident of Surrey (south of England) found the remains of a bird in the chimney of his house, to the paw of which a container with a message was attached. The text was intended for a certain XO2 and was signed "W Stot Sjt". After studying the message, experts from the British Government Communications Center came to the conclusion that without access to the books of codes used to create the cipher, it is almost impossible to find the right solution. “Such messages were created so that only the sender and recipient could read them. If we do not know at least something about who wrote this letter or to whom it was intended, we will not be able to decipher it, ”an anonymous employee of the Government Communications Center told the BBC.

On December 1, 1948, a man's body was found on Somerton Beach in Adelaide.. There were no signs of violence on the body, all that was found on him was cigarettes, a box of matches, a pack of chewing gum, a comb, a bus ticket and a train ticket. The pathologist who performed the autopsy was unable to determine the exact cause of his death, but suggested that the victim was most likely poisoned with poison, traces of which disappear from the body after a few hours. A month and a half later, the police found a suitcase at the Adelaide railway station, apparently belonging to the murdered man. Inside were various tools and clothes with tags torn off - including trousers with a secret pocket in which they found a piece of paper torn from a book with the inscription "Tamam Shud". The necessary book turned out to be an extremely rare edition of a collection of poetry by Omar Khayyam. On the last page, a cipher was written in pencil, which they have not been able to solve for more than 60 years. In 1978, the Australian Department of Defense issued a statement: it may be a cipher, it may be a meaningless set of characters, it is impossible to say for sure. Since 2009, attempts to decipher the cryptogram have been underway at the University of Adelaide. The researchers concluded that this is indeed some kind of cipher, but neither the cipher nor the Taman Shud case itself, one of the most famous mysteries in Australian history, still has a solution.

In the first edition of the book Codes and Ciphers ("Codes and ciphers") English cartographer and cryptographer of Russian origin Alexander D'Agapeev printed a cipher that still remains unsolved. After the book was published, the author admitted that he had forgotten the correct answer. In the next editions of Codes and Ciphers, there was no cryptogram. It has been proven that the D’Agapeev cipher is indeed based on a certain system (that is, it is not just a random set of characters), but it turned out to be too complicated. In the early 1950s, The Cryptogram magazine announced an award for cracking the code, but the correct answer has not yet been found.

On July 14, 1897, the famous English composer Edward Elgar sent a note to Dorabella- so he called his girlfriend Dora Penny. "Miss Penny," read one side of the card. The other had a three-line cipher of 87 characters. Dora was unable to decipher the message, and it sat in her desk drawer for 40 years before being reprinted in Penny's Elgar memoir. While deciphering the composer's letter, some tried to get by with the simplest method of replacing symbols with letters, while others came to the conclusion that it was not the words that were hidden here, but the melody. Some received messages in which absolutely nothing was clear, others - extremely lyrical texts, full of dreaminess and love. There is still no final decision; the decoding competition held in 2007 in honor of Elgar's 150th birthday also ended in nothing.

Georgia Guidestones- a large granite monument in Elbert County in the state of Georgia, USA. The monument contains a long inscription for 8 modern languages, and at the top of the monument there is a shorter inscription in 4 ancient languages: Akkadian, Classical Greek, Sanskrit and Ancient Egyptian. The monument does not contain encrypted messages, but its purpose and origin remain a mystery. It was erected by a man whose identity has never been established.

Voynich manuscript, which is often called the most mysterious book in the world. The manuscript uses a unique alphabet, it contains about 250 pages and drawings depicting unknown flowers, naked nymphs and astrological symbols. It first appeared at the end of the 16th century, when Holy Roman Emperor Rudolph II bought it in Prague from an unknown merchant for 600 ducats (about 3.5 kg of gold, today more than 50 thousand dollars). From Rudolph II, the book passed to the nobles and scientists, and disappeared at the end of the 17th century. The manuscript reappeared around 1912 when it was bought by the American bookseller Wilfried Voynich. After his death, the manuscript was donated to Yale University. British scholar Gordon Rugg believes that the book is a clever hoax.

The text has features that are not characteristic of any of the languages. On the other hand, some features, such as the length of words, the way letters and syllables are connected, are similar to those found in real languages. “Many people think that all this is too complicated for a hoax to build such a system, it would take some crazy alchemist years,” says Rugg. However, Rugg shows that such complexity could have been easily achieved using a cipher device invented around 1550 and called the Cardan grid. In this symbol table, words are created by moving a card with holes cut into it. Due to the spaces left in the table, the words are of different lengths. By imposing such grids on the manuscript's syllable table, Rugg has created a language that shares many, if not all, of the characteristics of the manuscript's language. According to him, three months would be enough to create the entire book.

Inspired by the Voynich manuscript, in 1981 the Italian designer and architect Luigi Serafini published his album, sustained in the same style: 360 pages of text in an unknown language and miniatures in the spirit of a medieval natural science treatise. Only if the historical manuscript can be suspected of describing some real flora and fauna, then Serafini's horses smoothly turn into caterpillars, and the boy and girl engaged in sex on the storyboard turn into a crocodile.

In all interviews, Serafini claims that the text is meaningless, and there is no need to look for logic in the sequence of miniatures - which, of course, only fuels interest in the book among cryptology enthusiasts.

Rongo-rongo, kohau rongorongo- wooden boards with inscriptions of the inhabitants of Easter Island. It is currently not clear whether each character represents single word or syllable. All rongo-rongos are made from toromiro wood. To date, only about 25 "plates" have been preserved in museums around the world. Traditionally, they are numbered with letters of the Latin alphabet, which, however, is not the only way designations of "tables", among which there is one wand, two inscriptions on the pectoral decoration of the reimiro, as well as an inscription on the snuffbox and on the figure of the tangata manu. Hieroglyphs - partly symbolic, partly geometric, in total about eight hundred different characters (according to Bartel's catalog).

Bale cryptograms- 3 encrypted messages containing information about the location of a treasure of gold, silver and precious stones, allegedly buried in Virginia near Lynchburg by a party of gold miners led by Thomas Jefferson Bale. The price of the unfound treasure in terms of modern money should be about 30 million dollars.

telegraph

Once, the elder Nastya and I avidly played detectives and detectives, came up with our own ciphers, methods of investigation. Then this hobby passed and then returned again. Nastya has a fiancé Dimka, who enthusiastically plays scouts. His passion was shared by my daughter. As you know, in order to transmit important information to each other, intelligence officers need a cipher. With the help of these games, you will also learn how to encrypt a word or even a whole text!

White spots

Any text, even without a cipher, can turn into hard-to-read gibberish if spaces are incorrectly placed between letters and words.

For example, this is what a simple and clear sentence turns into "Meet me at the lake" - "In a meeting with Yanaber yeguozera".

Even an attentive person will not immediately notice the catch. But experienced scout Dimka says that this is the simplest type of encryption.

without vowels

Or you can use this method - write the text without vowels.

For example, here is a sentence: "The note lies in the hollow of an oak, which stands at the edge of the forest". The encrypted text looks like this: "Zpska lie in dpl db, ktr stt n pshke ls".

It will require both ingenuity, and perseverance, and, possibly, the help of adults (who also sometimes do not hurt to train their memory and remember their childhood).

Read the other way around

This encryption combines two methods at once. The text must be read from right to left (that is, vice versa), and spaces between words can be placed at random.

Here, read and decipher: "Neleta minv oak, manoro tsop irtoms".

Second for first

Or each letter of the alphabet can be denoted by the letter following it. That is, instead of "a" we write "b", instead of "b" we write "c", instead of "c" - "d" and so on.

Based on this principle, you can create an unusual cipher. In order not to get confused, we made mini-cheats for all participants in the game. With them it is much more convenient to use this method.

Guess what phrase we encrypted for you: "T'ilb g tzhsibmzh fiobue mzhdlp - according to ojlpdeb oj toynbzhu schmarf".

Deputies

By the same principle as the previous cipher, the "Replacement" method is used. I read that it was used to encrypt sacred Jewish texts.

Instead of the first letter of the alphabet, we write the last one, instead of the second - the penultimate one, and so on. That is, instead of A - Z, instead of B - Yu, instead of C - E ...

To make it easier to decipher the text, you need to have an alphabet and a piece of paper with a pen at hand. You look at the correspondence of the letter and write it down. It will be difficult for a child to estimate by eye and decipher.

tables

You can encrypt the text by first writing it to the table. You just need to agree in advance which letter you will mark spaces between words.

A little hint - it should be a common letter (such as p, k, l, o), because letters that are rarely found in words immediately catch the eye and because of this the text is easily deciphered. You also need to discuss how large the table will be and how you will enter the words (left to right or top to bottom).

Let's encrypt the phrase together using the table: At night we go to catch carp.

The space will be denoted by the letter "r", the words are written from top to bottom. Table 3 by 3 (we draw in the cells of a regular notebook sheet).

Here's what we get:
N I M O T K A Y
O YU D R V A S R
CH R E L I R R E.

Lattice

In order to read the text encrypted in this way, you and your friend will need the same stencils: sheets of paper with squares cut out on them in random order.

Encryption must be written on a sheet of exactly the same format as the stencil. Letters are written in cells-holes (and you can also write, for example, from right to left or top to bottom), the remaining cells are filled with any other letters.

Key in the book

If in the previous cipher we prepared two stencils, now we need the same books. I remember back in the days of my childhood, boys at school used Dumas' novel "The Three Musketeers" for this purpose.

The notes looked like this:
"324 s, 4 a, c, 7 sl.
150 s, 1 a, n, 11 w…."

First digit indicated the page number
second- paragraph number
third letter- how should paragraphs be counted from above (c) or below (n),
fourth letter- word.

In my example, the desired words need to be searched:
First word: on page 324, in the 4th paragraph from the top, the seventh word.
Second word: on page 150, 1 paragraph from bottom, eleventh word.

The decryption process is not fast, but none of the outsiders will be able to read the message.

The time has come when satellites are flying above us, capable of zooming in on the image so much that we can accurately determine the size of the female breast of a girl lying on a nudist beach.

Having received such superpowers, we think that humanity knows absolutely everything. Even with all our high speeds, 3D technology, projectors and touch screens, there are still ciphers and codes that world-class cryptologists continue to puzzle over. Moreover, some ciphers existed in the 18th century. Even with the advent of advanced technology, these unsolved codes prove that the smartest thing in our society right now is smartphones.

10. Dorabella Cipher

It is said that its author had an exceptional mind. The ability to take a blank page and turn it into something intriguing is an art form that evokes incredible emotions... okay, maybe not so grandiloquently, but let's face it, it takes quite a lot of creativity to make something out of nothing. At the end of the 18th century, the author of this code, Edward Elgar, sent a coded message to his young girlfriend. The problem is that he managed to encrypt it so well that even she couldn't read it. Elgar was fascinated by the idea of encrypted messages. He even cracked one of the most difficult codes that was published in the famous Pall Magazine. Many have found the symbols that make up the Dorabella cipher in Elgar's musical compositions and his personal notes. Many have theories, but no one has ever found a solution.

9. D'Agapeyeff cipher

A couple of decades after the appearance of the Dorabella cipher, Alexander D'Agapeyeff wrote a book on cryptography. 1939, the year the book was written, was the time of pre-computer encryption, and it is believed that the D'Agapeyeff cipher was composed entirely by hand. This amazing code is harder to crack than prehistoric codes written in lost languages. The author of this cipher himself was a genius. His most famous code was so difficult that even he often gave in to it. Cryptologists have taken its numerical code and, as usual, assigned letters to the numbers. Unfortunately, it didn't lead to anything. They got a bunch of doubled and tripled letters. And the book of this cryptographer called "Codes and Ciphers", printed by Oxford Press, did not help. For some reason later editions did not include his known cipher. People were probably tired of the fact that at the very last moment, before they thought the secret would be revealed to them, the realization came that they were still far from it.

8. Harappan letter

Between 2600 and 1800 B.C. Harappan civilization flourished in the Indus Valley. The Indus people have been described in history as the most advanced urban culture of his time. The first attempts to decipher the Harappan script were made long before civilization was rediscovered. Historians from Britain to India have tried to decipher the symbolic messages. Some believe that the writing of the Indus people became the prototype of hieroglyphic writing in Ancient Egypt. Teams from Russia and Finland came to the conclusion that the writing of this people has druidic roots. No matter where it originated, the 400 pictogram alphabet has been developed by some of the world's greatest minds. It is believed that the population of the Harappan civilization was 1 million. To manage so many people, some form of language had to be invented. And at sunset, civilization decided to act quite selfishly, and did not leave a cheat sheet for future civilizations.

7. Chinese gold bar cipher

General Wang of Shanghai, received seven gold bars in 1933. But not at all the ones that are deposited in banks. The biggest difference was the mysterious images and letters found on the ingots. They consisted of cipher letters, Chinese characters and Latin cryptograms. 90 years later, they still haven't been hacked. Weighing 1.8 kilograms, the Chinese cipher is believed to describe a deal worth more than $300,000,000. the true reason that General Wang received such an elaborate gift from an unknown admirer would be much easier to determine if we knew what was written on the gold bars.

6. Killer Zodiac

This name has nothing to do with the daily horoscopes that fill our mailboxes, we are talking about one of the most terrible serial killers. Not only was he guilty of a huge number of murders and was simply a mentally unbalanced person, the Zodiac tried to become famous at their expense. In 1939, he sent letters to three California newspapers boasting about the recent murders in Vallejo. For his generosity, he demanded that a coded message be printed on the front pages of these newspapers. In the end, the police were left with no choice but to play his game. More than 37 people became victims during his activities in the 1960s and 1970s, and it is surprising that several Zodiac messages were deciphered. However, the vast majority still keep their secret. The FBI even went so far as to release the rest of his messages to the public in the hope that someone could decipher them.

5. Linear A

Historians have succeeded in making a connection between the Phaistos Disc and Linear A, but they still need to decipher the message. The Phaistos disc was found in 1908, with mysterious signs on both sides. "Experts" identified 45 characters, but they still don't know what they mean. In addition, they found many discs with two different styles of writing. One style was called "Linear A" and the other "Linear B". Linear A was much older and was created on the island of Crete. A Briton named Michael Ventris put all "experts" to shame when he cracked the Linear B cipher. The secondary form was broken, but the "experts" are still scratching their heads over Linear A.

4. Proto-Elamite

Having formed the Persian Empire, the Elamites became the very first civilization known to us. Even in 3300 BC. it was necessary to develop a written language in order to communicate with each other. In the 8th century BC. The Elamites used clay symbols to represent various goods and services. They even came up with clay wallets and IDs to understand who had money and how much. This is the earliest evidence for the creation of a number system. Around 2900 BC their language has moved to a whole new level. It is assumed that the Proto-Elamite language was some form of accounting system.

Some advances, if you can call them that, have been made by historians who have found similarities between Proto-Elamite and cuneiform writing. Unfortunately, at the beginning of the 5th century BC. Proto-Elamite began to disappear. There are only 1,600 clay discs left that no one can read.

3. Taman Shud

As the Zodiac has already proven, killers love fame. The body of an unidentified Australian was found on the shores of Adelaide Beach over 65 years ago. The media dubbed him " by a mysterious person from Somerton". Attempts to find out his identity were also unsuccessful. But today we are talking about ciphers ... The evidence found in his pockets led the Australian police to the local railway station. There they found his suitcase with a set of things common to most people The coroner stated that the man was perfectly healthy (besides being dead) and may have been poisoned.

It took two whole months to discover a small pocket, which was missed at the first examination. It contained a small piece of paper with the inscription "Taman Shud". After the discovery of this find, a guy approached the police, claiming to have found a copy of the same book in his car on the same evening that the stranger was killed. Under ultraviolet radiation, an unreadable code of five lines appeared. For years, officials and various volunteers have been trying to break the cipher. Professor Derek Abbott and his students have been trying to decipher the message since March 2009. However, like other mystery lovers, they gave up. But their reports say that the victim was a spy for the times cold war who was poisoned by enemies. It is much easier to come up with something mystical than to fully taste the bitter taste of defeat.

2. McCormick cipher

The body of Ricky McCormick was found in the Missouri area on June 30, 1999. Two years after his death, two notes in his pockets were the only clues for detectives. Even the efforts of the most famous cryptologists and the American Cryptology Association have not been able to decipher them. The McCormick cipher is ranked 3rd in the list of the most difficult codes. More than 30 lines of encoded information include numbers, lines, letters and brackets. With so many characters, the possible ciphers are endless. McCormick's family says he has been writing in ciphers since childhood, and none of them knew what they meant. Although he was away for only a few days, McCormick's body was quickly identified. This made the deciphering of his notes a clue to his murder. FBI agents usually crack codes in a few hours. One way or another, McCormick, who normally could only write his own name, made serious competition for the professionals.

1. Bacon's cipher

The Voynich manuscript is the largest illustrated work written in cipher. The illustration, rediscovered to the world at the Jesuit School in 1912, got its name because the authorship is attributed to the Englishman Roger Bacon. Some historians discredit Bacon's authorship due to the presence of letters of the alphabet that were not used during his lifetime. On the other hand, the illustrations confirm Bacon's participation in the creation of the work. He was known for his interest in creating the elixir of life and other mystical teachings. Similar themes have been mentioned within the Voynich Manuscript. Was Bacon really interested in the unknown? We'll leave this debate to others, but one thing that remains undisputed is that we don't know what this cipher hides. A huge number of attempts have been made to crack the code. Some have argued that it is a modified Greek shorthand, while others have suggested that the key is in the illustrations. All theories have failed. Those who are still trying to break Bacon's cipher are amazed that it has taken so long to crack.

Ever since mankind has grown to writing, codes and ciphers are used to protect messages. The Greeks and Egyptians used ciphers to protect personal correspondence. In fact, it is from this glorious tradition that the modern tradition of breaking codes and ciphers grows. Cryptanalysis studies codes and methods for breaking them, and this activity in modern realities can bring a lot of benefits. If you want to learn this, then you can start by studying the most common ciphers and everything connected with them. In general, read this article!

Steps

Decryption of substitution ciphers

Start by looking for words with one letter. Most ciphers based on relatively simple substitutions are easiest to break with simple brute force substitution. Yes, you will have to tinker, but it will only get more difficult.

Words from one letter in Russian are pronouns and prepositions (I, v, u, o, a). To find them, you will have to carefully study the text. Guess, check, fix or try new options - there is no other way to solve the cipher.
You must learn to read the cipher. Breaking it is not so important. Learn to snatch the patterns and rules that underlie the cipher, and then breaking it will not be fundamentally difficult for you.

Look for the most commonly used symbols and letters. For example, in English these are “e”, “t” and “a”. When working with a cipher, use your knowledge of the language and sentence structure, on the basis of which you make hypotheses and assumptions. Yes, you will rarely be 100% sure, but solving ciphers is a game where you are required to make guesses and correct your own mistakes!
- Look for double characters and short words first of all, try to start decoding with them. It's easier, after all, to work with two letters than with 7-10.
Pay attention to apostrophes and symbols around. If there are apostrophes in the text, then you are in luck! So, in case in English, the use of an apostrophe means that characters such as s, t, d, m, ll, or re are encrypted after. Accordingly, if there are two identical characters after the apostrophe, then this is probably L!

Try to determine what type of cipher you have. If, while solving a cipher, at a certain moment you understand which of the above types it belongs to, then you have practically solved it. Of course, this will not happen so often, but the more ciphers you solve, the easier it will be for you later.
- Digital substitution and key ciphers are the most common these days. When working on a cipher, the first thing to check is if it is of this type.
Recognition of common ciphers
1. substitution ciphers. Strictly speaking, substitution ciphers encode a message by replacing one letter with another, according to a predetermined algorithm. The algorithm is the key to unraveling the cipher, if you unravel it, then decoding the message will not be a problem.
  - Even if the code contains numbers, Cyrillic or Latin, hieroglyphs or unusual characters - as long as the same types of characters are used, then you are probably working with a substitution cipher. Accordingly, you need to study the alphabet used and derive substitution rules from it.
2. Square cipher. The simplest encryption used by the ancient Greeks, based on the use of a table of numbers, each of which corresponds to a letter and from which words are subsequently composed. It's really simple code, sort of the basics. If you need to solve a cipher in the form of a long string of numbers, it is likely that square cipher methods will come in handy.
  
  Caesar's cipher. Caesar not only knew how to do three things at the same time, he also understood encryption. Caesar created a good, simple, understandable and, at the same time, resistant to cracking cipher, which was named after him. The Caesar Cipher is the first step towards learning complex codes and ciphers. The essence of the Caesar cipher is that all the characters of the alphabet are shifted in one direction by a certain number of characters. For example, shifting 3 characters to the left will change A to D, B to E, and so on.
  
  Watch out for keyboard templates. Based on the traditional QWERTY keyboard layout, various ciphers are currently being created that work on the principle of displacement and substitution. The letters are shifted left, right, up and down by a certain number of characters, which allows you to create a cipher. In the case of such ciphers, you need to know in which direction the characters were shifted.
  - So, changing the columns one position up, "wikihow" becomes "28i8y92".
  - polyalphabetic ciphers. Simple substitution ciphers rely on the cipher to create a sort of alphabet for encryption. But already in the Middle Ages it became too unreliable, too easy to crack. Then cryptography took a step forward and became more complicated, starting to use characters from several alphabets for encryption at once. Needless to say, the reliability of encryption immediately increased.
What does it mean to be a codebreaker

When encrypted by the substitution method, the letters of the source text can be replaced by geometric figures, figurines of people, animals, any drawings, symbols, letters or numbers (groups).

EACH LETTER IS ENCODED ONLYONE NUMBER

IN Appendix No. 30 a simple substitution method is shown, where 33 numbers are used to encode 33 letters. Each of the 33 letters is replaced by one of the numbers: 01, 02, 03, ..., 33.

Option 1

This table encoded an encryption from a children's coloring book. Modern alphabetic positional numbering is similar to the numerical correspondence of a letter in Slavic alphabet. This is a simple table. Here the numbers used for encoding are in order.

Option 2

Here the numbers (two-digit digital groups) are drawn in a lottery order according to the principle of random numbers.

In case of theft, loss (compromise) of the table, you can complicate it - agree to rearrange the numbers in each group. For example, A \u003d 05 - write 50 in encryption.

EACH LETTER IS ENCODEDTWO GROUPS

The total number of numbers (digit groups) used for encoding is 2 times more than letters.

In table number 1 ( application no. 31) - 49 letters, numbers and signs + reserve, for encoding of which 100 numbers (groups) are used. The first and second lines are two-digit groups used for encoding. Groups “36” and 63” - reserve. Third, bottom line - letters, numbers and punctuation marks. To encode each letter, one or the other group (standing above the letter) is used, alternating alternately. In this table, the groups are arranged in numerical order. Tables of this type are not difficult to store in memory.

In table number 2 ( application no. 32) the groups used for coding are arranged randomly. Table #2 consists of two tables. The left table is for encoding (code table). The right one is for decoding (decryption). Opposite each letter (in the left table) there are two two-digit groups that are used to replace this letter, alternating alternately. For example, the word “hut” will look like this: 15 68 06 12 82. To mislead the enemy, this ciphergram can be written like this: 156 806 128 224 or like this: 1568 0612 8276. To complete the last group, we use the reserve.

USE TO REPLACE EACHSEVERAL GROUP LETTERS

In the encryption process, 3, 4 or more groups can be used to replace each letter . Accordingly, the total number of groups used for encryption can be 3, 4 and n times more than the letters in the alphabet.

COMPLEX ENCODING.

Unlike appendix #30, all numbers used here to encode letters are taken from the multiplication table. The word "SHALASH" encoded according to the code table presented in Appendix No. 33, will look like this: 10 24 40 24 10.

Complicating using the multiplication table, we replace the letter code with multipliers: instead of “10”, we write “25” or “52” (2´5 = 5´2 = 10), “24” we replace with “38”, “83”, “ 46" or "64" (3´8 = 8´3 = 4´6 = 6´4 = 24) and so on. not one number is used, but several (2-4), which will make the cipher more reliable, since in the ciphertext the same numbers (groups) will be repeated less often.

Even if you lose such a table, or it is stolen, peeped, copied, attackers will not be able to use (decrypt) it. there will be no digital groups from the code table in the cryptogram, but there will be groups consisting of factors.

In order not to attract the attention of outsiders, the ciphergram can be disguised as the arithmetic operations of a first grader and written as follows:

Classwork

2´5 = 10, 3´8 = 24, 8´5 = 40, 4´6 = 24, 5´2 = I0

The message can be sent in short parts.

Similarly to the above, you can use the "Four-digit mathematical tables" by V.M. Bradis - exact works two-digit numbers. A four-digit number is decomposed into 2 two-digit factors.

A DIFFERENT NUMBER OF GROUPS IS USED TO REPLACE EACH LETTER

Consider the encryption system in the form of a table of size 10‰10 (sizes may be different). Let's number the rows and columns. The tenth row and column will be denoted by zero (numbering can be started not from 1, but from 0). Numbering can be alphabetic. Moreover, for the numbering of rows and columns, not the same, but different letters can be used. Each cell has coordinates consisting of two numbers or letters - a row number and a column number. Fill in the cells of the table with the letters of the alphabet, the necessary punctuation marks, and numbers. At the same time, we will distribute 100 cells proportionally, depending on the frequency of the use of letters in the Russian language. Let's leave some cells empty. Blanks, if necessary, will be used instead of spaces, to indicate a red line, to complete the last groups (in case of regrouping) and as a reserve.

In the simplest version, the letters are entered into the table in alphabetical order, and the numbers in ascending sequence (this arrangement of characters is not difficult to remember). Moreover, frequently occurring letters are repeated the required number of times: so the letter O will take 8-9 cells, the letter E will take 7-8 cells, the letter A is repeated 6-7 times, the letter I will be written 5-6 times, etc. Rows and columns can be numbered in reverse or random order.

In a more complicated version, some memorized text (for example, a poem) is first entered, then the letters of the alphabet that are not included in this text are added. First, any memorable numbers are entered (for example, 1945 - the year the Second World War ended), then the rest. Thus, the arrangement of characters in the table will be conditionally random, which increases the strength of the cipher. Apply different rules filling in the table in an easy-to-remember order. In our example, in a table ( application no. 34) at the beginning, the memorized phrase is written, followed by the memorized numbers, then the rest of the letters of the alphabet, followed by punctuation marks and the remaining numbers, and finally, the required number of frequently occurring letters are added. The numbering of rows and columns has two options (numeric and alphabetic).

In the process of encryption, the letter of the source text is found in the table and replaced by a two-digit numeric group (coordinates), in which one digit is the row number, and the other is the column number.

Let's encrypt the text (BIG BIG PROFIT THAN A LITTLE DEFECT.) and get the cryptogram (17 45 49 40 10 37 13 88 18 40 24 43 39 95 15 12 29 23 96 11 57 49 21 44 89 68 17 7 7 19 18 87 16 43 80 78 76 97 05 25 69 08 98 11 50). In the resulting cryptogram, despite the short plaintext, repeated (identical) two-valued groups are viewed. If the encryption is regrouped into groups of 3, 4 or 5 characters, repetitions of the same two-digit groups will not be noticeable.

If you apply the alphabetic numbering of rows and columns, the ciphergram will have a different form: LZH OD OI OK LK NJ LV TZ LZ OK MG OV NI UD LD LB MI MV UE LA PJ OI MA OG TI RZ LZH LI LZ TJ LE OV TK SZ SE UZH FD MD RI FZ UZ LA PC. To make it more complicated, in every second group of the ciphergram, the characters can be written in reverse order - first the column number, and then the line number. Or combine - alternate between numeric and alphabetic groups.

The table in question is different from the column-by-column replacement table shown in Appendix No. 32, by the fact that in addition to the random character-two-valued group correspondence, we have an unequal (approximately proportional to the frequency of use) number of replacement groups for different letters, which reduces the manifestation of regularities and characteristics of the source text in the ciphergram.

CIPHRO NOTEBOOK

Take an ordinary notebook (notebook) with the alphabet. Add the missing letters to it: Yo, Y, b, Y, b. It is also desirable to add punctuation marks to the notepad after the letters: a period, a comma, a question mark. In total, there are 36 letters and signs in the notebook. If necessary, you can enter - numbers and other characters.

For encryption, use 1000 groups, three digits each ( three-digit numbers): 000, 001, 002, 003 and so on up to 999.

For simplicity, distribute the three-digit groups equally. 1000: 36 = 27 and 28 remainder. Use 27 groups to encrypt each letter and punctuation marks. Leave the remaining 28 in reserve. For the reserve, select a separate page.

When compiling a notebook, three-digit groups are selected in a lottery order according to the principle of random numbers. To do this, cut out small rectangular pieces from cardboard - 1000 pieces. Write a number on each: 000, 001, 002, 003, etc. up to 999. Put them in a box, mix. Open notepad on the page with the letter -“A”. Take any number from the box, for example, 323. Write this number in a notebook on the page with the letter - “A”. Put this number in another empty box. Take the second number from the box, for example, 162. Write this number in a notebook, and put the number in another box.

Take out the next, third, number from the box. Write down the next number in a notebook, for example, 952. And so on. until 27 groups are written on the page with the letter “A”.

323 162 952 338 566 532 959 379 005 837 832 582 035 818 460 615 907 464 814 931 564 690 305 405

336 259 179 286 177 059 236 790 971 113 504 390 910 331 458 422 856 496 025 370 217 232 794 598 724 345 486

Similarly, type and enter numbers (three-digit numerical groups) for other letters and punctuation marks. Record the remaining 28 groups in the reserve.

To decrypt on free sheets, at the beginning of the notebook, make a special table - DESCHIFRANT. The decoder consists of two columns. The first column is No. in order, three-digit groups: 000, 001, 002, 003, etc. up to 999. Second column - letters and signs. First, write in the notebook the first column - serial numbers. Then fill in the second column - opposite each serial number, the corresponding letter or sign.

To do this, open notepad on the page with the letter "A". The first group here is 323. Against serial number 323 of the decipher, write the letter "A". The second group is 162. Write the letter “A” against the serial number 162 in the decipher, and so on.

Next, open a notepad on the page with the letter - “B” and in the decipher against the corresponding groups (serial numbers) put down the letter “B”. Similarly, fill in the second column of the decipher with the rest of the letters and punctuation marks. Against groups that fell into the reserve - empty (for example, No. 260).

The cipher pad and its decryptor are shown in Appendix No. 35.

TEXT ENCRYPTION

For example, you need to encrypt the word - "BABA". The first letter in the text is "B". Open notepad on the page with the letter "B". The first group is 336. Write it under (above) the first letter “B” in the text. See the text further, if there are more letters “B” in the text. Encrypt the second letter “B” with the second group - 259, etc. Encrypt each letter with a new group until all the letters "B" in the text are encrypted. This technique eliminates the reuse of groups.

We return to the beginning of the original text. The second letter in the text is "A". Open notepad to the page with the letter "A". The first group here is 323. Write it under the letter "A". Encrypt the next letter “A” with the second group - 162. And so on, until all the letters “A” in the text are encrypted.

Encrypt the remaining letters of the text in the same way (they are not in the example above). The result was a ciphertext: 336 323 259 162. To replace each letter, you can use any of the 27 groups intended for this letter, in any order, without allowing the same group to be reused.

DECRYPTION

To decrypt the cryptogram, find serial number 336 in the decipher. Opposite it is the letter

- "B". Write the letter "B" under the first group of the ciphergram. The second group in the ciphertext is 323. Find serial number 323 in the decipher. Opposite it is the letter - “A”. Write it down under the second group of the ciphertext. Etc.

It turns out:

RULES OF WORK

Confidential information and SRS-DRC must be handled in the absence of outsiders. Encryption does not allow reuse of the same group. If the text is large and the notepad does not allow you to encrypt the entire text without reusing groups, break it into parts and transmit in parts, as separate ciphertexts.

Destroy damaged sheets and drafts, as well as ciphertexts and secret texts that have lost their meaning.

If you need to enter other characters or numbers in the notebook, use part of the reserve. The numbers can be placed separately after the letters at the end of the notebook or together with the letters in alphabetical order: 1 - one - after the letter "O", 2 - two - after the letter "D", etc. Reserve groups can be used as a section sign (to indicate a space or a red line), to complete the last groups when regrouping a ciphergram, and in other cases.

Of course, when making a cipher block, it is necessary to distribute replacement elements (cipher designations) for each letter not equally, but in an amount proportional to the frequency of use of letters in the Russian language. But the uniform distribution of three-digit digital groups, shown on the example of this cipher pad, makes it possible to more conveniently and efficiently change the key. Allows you to apply a shift by one or more positions. The alphabet of the cipher pad is numbered. Numbering starts from zero, i.e. the letter "A" is assigned the serial number 0, the letter "B" - the serial number 1, the letter "C" - 2, etc. This numbering helps to navigate well and calculate the groups needed for replacement.

So, for example, when shifting by three positions (the key is 3), to replace the letter “A”, the groups intended for the letter “G” are used - to the ordinal number of the letter “A” (0) we add the value of the key (3) and get the ordinal number letters "G" (3). The letter of the source text "B" in the encryption process is replaced by three-digit digital groups intended for the letter "D" - the serial number of the letter "B" (1) is added with the value of the key (3) and we get the serial number of the paragraph corresponding to the letter "D" ( 4), etc.

You can split the alphabet in pairs and use the groups intended for the letter "B" to replace the letter "A". To replace the letter "B", use the groups intended for the letter "A", and so on.

Change the key according to a special secret schedule (key change schedule).