Criptografia no .NET Framework

Cryptography : Symmetric Encryption by Symmetric Algorithm Classes – Part 1
http://www.codeproject.com/Articles/442523/Cryptography-Symmetric-Encryption-by-Symmetric-Alg

Cryptography : Asymmetric Encryption by using Asymmetric Algorithm Classes.
http://www.codeproject.com/Articles/448719/Cryptography-Asymmetric-Encryption-by-using-Asymme

Generating Keys for Encryption and Decryption
http://msdn.microsoft.com/en-us/library/5e9ft273%28v=vs.110%29.aspx