COFFEE TABLE
You find yourself back at the coffee table, what would you like to look at?
It’s the same newspaper from last week with the article about Miss Lehman in the dumpster. Wait a minute, something looks different now that the lights are out!
It’s a weird looking book with letters and things that don’t make any sense on the cover. Oh, it’s a book about “Ciphers”. There are a few pages bookmarked:
The Atbash Cipher was originally a monoalphabetic substitution cipher used for the Hebrew alphabet. It is one of the earliest known substitution ciphers to have been used, and is very simple. However, its simplicity is also its biggest pitfall, as it does not use a key. Hence every piece of plaintext enciphered using the Atbash Cipher uses the same ciphertext alphabet, and so can be easily broken, since the encryption algorithm is known to all. The Atbash Cipher simply reverses the plaintext alphabet to create the ciphertext alphabet. That is, the first letter of the alphabet is encrypted to the last letter of the alphabet, the second letter to the penultimate letter and so forth. In the original Hebrew this means that ‘aleph’ is encrypted to ‘tav’, and ‘beth’ to ‘shin’. This is where we get the name of the cipher ‘atbash’.
For the Roman alphabet of 26 letters, we have the ciphertext alphabet as given in the table below.
As with any monoalphabetic substitution cipher, encryption using the Atbash Cipher is very simple. We simply replace each occurrence of each plaintext letter with the respective ciphertext letter given by the table. So, if we take the plaintext “atbash”, we can see that “a” enciphers to “Z”, “t” enciphers to “G” and so on. Continuing in this way, we see that the final ciphertext is “ZGYZHS”.
Due to the symmetric nature of this cipher, the decryption process is exactly the same as the encryption process. In this case, the ciphertext alphabet relies only on the alphabet used, and hence the table above is also used to decipher the message. So, given the ciphertext “XRKSVI”, and assuming that the alphabet used was the standard Roman alphabet of 26 letters, we can retrieve the plaintext “cipher”.
The Caesar (or Shift) Cipher is a monoalphabetic substitution cipher. Although more secure than the Atbash Cipher, it is still an easy cipher to break, especially by today’s standards. Originally, it was used by Julius Caesar for sending encrypted messages to his troops.
The encryption process requires designating how many spaces each letter in the text is going to be shifted in order to create the cipher. For example, a Caesar Shift of “2” means all letters in the original message will be shifted forward by 2 in the alphabet. A becomes C, B becomes D, etc. See example below:
Decryption involves reversing the shift in order to derive the original letter. To decrypt a text with a Caesar Shift of “2”, you would move backwards in the alphabet two spaces for each letter. For example, D would become B, and C would become A.
The Pigpen Cipher is a form of substitution cipher where the letters/numbers are replaced by symbols. The cipher has an interesting history: although its true origins are unknown, it has been used by many groups. Most notoriously, it was the cipher of choice for use by the Freemasons, a secret society in the 18th Century. In fact, they used it so much that it is often referred to as the Freemasons Cipher.
The encryption process is fairly straightforward, replacing each occurrence of a letter/number with the designated symbol. The symbols are assigned to the letters/numbers using the key shown below, where the letter/number shown is replaced by the part of the image in which it is located.
The decryption process is just the reverse of the encryption process. Using the same key (the grid above), you locate the image depicted in the ciphertext, and replace it with the letter/number given by that part of the grid.
It’s a weird looking book with letters and things that don’t make any sense on the cover. Oh, it’s a book about “Ciphers”. There are a few pages bookmarked:
The Atbash Cipher was originally a monoalphabetic substitution cipher used for the Hebrew alphabet. It is one of the earliest known substitution ciphers to have been used, and is very simple. However, its simplicity is also its biggest pitfall, as it does not use a key. Hence every piece of plaintext enciphered using the Atbash Cipher uses the same ciphertext alphabet, and so can be easily broken, since the encryption algorithm is known to all. The Atbash Cipher simply reverses the plaintext alphabet to create the ciphertext alphabet. That is, the first letter of the alphabet is encrypted to the last letter of the alphabet, the second letter to the penultimate letter and so forth. In the original Hebrew this means that ‘aleph’ is encrypted to ‘tav’, and ‘beth’ to ‘shin’. This is where we get the name of the cipher ‘atbash’.
For the Roman alphabet of 26 letters, we have the ciphertext alphabet as given in the table below.
As with any monoalphabetic substitution cipher, encryption using the Atbash Cipher is very simple. We simply replace each occurrence of each plaintext letter with the respective ciphertext letter given by the table. So, if we take the plaintext “atbash”, we can see that “a” enciphers to “Z”, “t” enciphers to “G” and so on. Continuing in this way, we see that the final ciphertext is “ZGYZHS”.
Due to the symmetric nature of this cipher, the decryption process is exactly the same as the encryption process. In this case, the ciphertext alphabet relies only on the alphabet used, and hence the table above is also used to decipher the message. So, given the ciphertext “XRKSVI”, and assuming that the alphabet used was the standard Roman alphabet of 26 letters, we can retrieve the plaintext “cipher”.
For the Roman alphabet of 26 letters, we have the ciphertext alphabet as given in the table below.
As with any monoalphabetic substitution cipher, encryption using the Atbash Cipher is very simple. We simply replace each occurrence of each plaintext letter with the respective ciphertext letter given by the table. So, if we take the plaintext “atbash”, we can see that “a” enciphers to “Z”, “t” enciphers to “G” and so on. Continuing in this way, we see that the final ciphertext is “ZGYZHS”.
Due to the symmetric nature of this cipher, the decryption process is exactly the same as the encryption process. In this case, the ciphertext alphabet relies only on the alphabet used, and hence the table above is also used to decipher the message. So, given the ciphertext “XRKSVI”, and assuming that the alphabet used was the standard Roman alphabet of 26 letters, we can retrieve the plaintext “cipher”.
The Caesar (or Shift) Cipher is a monoalphabetic substitution cipher. Although more secure than the Atbash Cipher, it is still an easy cipher to break, especially by today’s standards. Originally, it was used by Julius Caesar for sending encrypted messages to his troops.
The encryption process requires designating how many spaces each letter in the text is going to be shifted in order to create the cipher. For example, a Caesar Shift of “2” means all letters in the original message will be shifted forward by 2 in the alphabet. A becomes C, B becomes D, etc. See example below:
Decryption involves reversing the shift in order to derive the original letter. To decrypt a text with a Caesar Shift of “2”, you would move backwards in the alphabet two spaces for each letter. For example, D would become B, and C would become A.
The encryption process requires designating how many spaces each letter in the text is going to be shifted in order to create the cipher. For example, a Caesar Shift of “2” means all letters in the original message will be shifted forward by 2 in the alphabet. A becomes C, B becomes D, etc. See example below:
Decryption involves reversing the shift in order to derive the original letter. To decrypt a text with a Caesar Shift of “2”, you would move backwards in the alphabet two spaces for each letter. For example, D would become B, and C would become A.
The Pigpen Cipher is a form of substitution cipher where the letters/numbers are replaced by symbols. The cipher has an interesting history: although its true origins are unknown, it has been used by many groups. Most notoriously, it was the cipher of choice for use by the Freemasons, a secret society in the 18th Century. In fact, they used it so much that it is often referred to as the Freemasons Cipher.
The encryption process is fairly straightforward, replacing each occurrence of a letter/number with the designated symbol. The symbols are assigned to the letters/numbers using the key shown below, where the letter/number shown is replaced by the part of the image in which it is located.
The decryption process is just the reverse of the encryption process. Using the same key (the grid above), you locate the image depicted in the ciphertext, and replace it with the letter/number given by that part of the grid.
The encryption process is fairly straightforward, replacing each occurrence of a letter/number with the designated symbol. The symbols are assigned to the letters/numbers using the key shown below, where the letter/number shown is replaced by the part of the image in which it is located.
The decryption process is just the reverse of the encryption process. Using the same key (the grid above), you locate the image depicted in the ciphertext, and replace it with the letter/number given by that part of the grid.
The drawer is locked. If you find a key, you can try to unlock it by entering the key’s tag ID here:
The drawer is locked. If you find a key, you can try to unlock it by entering the key’s tag ID here: