Implementing Cryptography on a Handheld Device

Many situations in the real time development force us to encrypt a relatively small amount of data, such as a file or even a small piece of data stored in a file. . NET Framework providesSystem.Security.Cryptography namespace that contains classes that provide a managed interface to the underlying Windows CryptoAPI allows encrypting and decrypting files. This namespace includes a number of CryptoServiceProvider classes that allow you to use DES, DSA, MD5, RC2, RSA, SHA1 or TripleDES encryption algorithms.

These classes are not supported in version 1 of the .NET Compact Framework. However, Windows CE does support an implementation of the CryptoAPI, so if you need fine-grained encryption, you can use P/Invoke to call out to it and perform cryptographic operations that way.