What is Null cipher?

Understanding Null cipher

Hiding plaintext within other plaintext. A form of steganography. A null cipher is a method of concealing a message within another innocent-looking message not by transforming the content as in encryption but by hiding it within a seemingly innocuous communication. The hidden message might be extracted by reading only certain letters words or applying other predetermined rules. Null ciphers are a form of steganography rather than true cryptography. Historical null ciphers appear in espionage literature and have evolved into modern steganographic techniques. Organizations might implement steganographic techniques for specific use cases like digital watermarking but generally rely on strong encryption rather than null ciphers for protecting sensitive information. For example a digital rights management system might use steganographic techniques to embed invisible watermarks in media files that identify the legitimate owner while still relying on encryption for content protection. Related terms Steganography Hidden messages Covert channel Digital watermarking Information hiding Cryptography Concealment.