.NET Security and Cryptography

Symmetric Ciphers

A symmetric cipher is a cipher in which encryption and decryption use the same key or keys that are mathematically related to one another in such a way that it is easy to compute one key from knowledge of the other, which is effectively a single key. Since the single key is the only secret to encryption and decryption, it is critical that this key be kept strictly private. Otherwise, an interloper could easily encrypt and decrypt messages at will, and we would be leaking information and accomplishing nothing. For this reason, symmetric ciphers are often referred to as private key, secret key, or shared key ciphers. In contrast, asymmetric ciphers involve the use of a pair of keys that are mathematically related, but it is intentionally ...