Chilkat Crypt .NET is an advanced encryption component that offers both RSA public-key

encryption with digital signatures as well as symmetric encryption algorithms including

AES (Rijndael), Blowfish, and Twofish. It provides the ability to easily create digital

signatures for files or memory data, or verify digital signatures against incoming

data or files. It allows for the use of any Cryptographic Service Provider, including
Smart
Card implementations from 3rd-party vendors. It also provides easy access to
information
about digital certificates and the ability to add and delete certificates
from certificate
stores found in the registry, filesystem, or even directly in memory.