Keyless and Keyed Transposition techniques | Types of transposition techniques in Cryptography
Transposition Techniques Overview
Introduction to Transposition Techniques
- Abhishek introduces the topic of Transposition Techniques, specifically focusing on the Transposition Cipher.
- He references a previous video where he explained the basic concepts and provided an example using columnar transposition.
Keyless Transposition Cipher
- The discussion shifts to keyless types of Transposition Ciphers, emphasizing that no specific key is used in this method.
- The Real Fence Technique is highlighted as an example of a keyless transposition cipher, where plaintext is arranged in columns without a key.
Methodology of Keyless Transposition
- Abhishek explains how plaintext can be organized into a diagonal format for encryption, demonstrating with "meet me at the park."
- He describes two methods: writing text into a table column by column and reading it row-wise to generate ciphertext.
Second Method Explanation
- In the second method, characters are permuted by dividing plaintext into blocks of predetermined sizes.
- This involves applying keys to each block separately to create ciphertext from groups of characters.
Example Application
- An example is given where Alice sends a message "enemy attacks tonight," divided into groups for encryption.