2024年7月18日 · The encryption of the original text is done using the Vigenère square or Vigenère table. The table consists of the alphabets written out 26 times in different rows, each alphabet shifted cyclically to the left compared to the previous alphabet, corresponding to the 26 possible Caesar Ciphers.

The Vigenère cipher (French pronunciation: [viʒnɛːʁ]) is a method of encrypting alphabetic text where each letter of the plaintext is encoded with a different Caesar cipher, whose increment is determined by the corresponding letter of another text, the key.

We shall use Vigenère Table. The first row of this table has the 26 English letters. Starting with the second row, each row has the letters shifted to the left one position in a cyclic way. For example, when B is shifted to the first position on the second row, the letter A moves to the end.

2025年1月2日 · Vigenère cipher, type of substitution cipher used for data encryption in which the original plaintext structure is somewhat concealed in the ciphertext by using several different monoalphabetic substitution ciphers rather than just one; the code key specifies which particular substitution is to be employed for encrypting each plaintext symbol.

In the Vigenère cipher, a message is encrypted using a secret key, as well as an encryption table (called a Vigenere square, Vigenere table, or tabula recta). The tabula recta typically contains the 26 letters of the Latin alphabet from A to Z along the top of each column, and repeated along the left side at the beginning of each row.

The Vigenère Table (also known as the Vigenère Cipher table) is a table used to determine the values of the ciphertext based on the plaintext and the key. The table consists of rows and columns, where each row corresponds to one of the letters of the alphabet, and each column corresponds to a character of the key.

In essence, the Vigenère Cipher is an adaptation of the Trithemius Cipher, but instead of systematically progressing through the ciphertext alphabets in the Tabula Recta, it uses a keyword to pick which columns to use. To encrypt a message using the Vigenère Cipher you first need to choose a keyword (or keyphrase).

One way of looking at this is to notice that each letter of our keyword RELATIONS picks out 1 of the 26 possible substitution alphabets given in the Vigenere tableau. Thus, any message encrypted by a Vigenere cipher is a collection of as many simple substitution ciphers as there are letters in the keyword.

The Vigenère cipher,utilizes a simple table and a keyword to transform a plaintext message into a coded one, and vice versa. This section will delve into the specifics of how the Vigenère cipher operates, breaking down the Vigenère table, and the encryption and decryption process.

The Vigen`ere cipher uses a 26 × 26 table with A to Z as the row heading and column heading (Figure 2). This table is usually referred to as the Vigen`ere Tableau, Vigen`ere Table or Vigen`ere Square.