The Microsoft patterns & practices mobile Password Authentication and mobile Configuration Application Blocks provide encryption and authentication services that meet the needs of many line-of-business mobile applications. However, they do not provide solutions for every security and encryption need. In this section, we discuss how to use the System.Security.Cryptography namespace directly to perform common encryption tasks.
A symmetric algorithm is one in which exactly the same key is used for encryption and decryption. The most commonly used symmetric algorithm is Rijndael, which is the algorithm selected for the U.S. government Advanced Encryption Standard (see the sidebar titled