Other Encryption Schemes

Many encryption schemes fit neatly into the symmetric or asymmetric categories, but a few fall outside the scope of these categories. For example, cryptographers can use steganography to manipulate files and embed detailed messages within them. However, steganography simply hides the data within the file and doesn’t use a key. IPsec is another encryption scheme that doesn’t fit neatly into the symmetric and asymmetric categories, but it is important in the context of cryptography.

Steganography

Steganography is the practice of hiding data within data, or hiding data in plain sight. For example, a check can have a watermark embedded within it, and if someone knows what to look for, the watermark provides additional information that wouldn’t be apparent to someone unaware of the watermark.