Here are some simple samples which compare RSA encryption in Java2, .NET
and CryptoAPI:
  http://www.jensign.com/JavaScience/dotnet/RSAEncrypt

- Michel Gallant
  MVP Security
  http://www.jensign.com

You're using Java Cryptography Architecture (JCA).
To work with it, you must use one or more
cryptographic provider.

A Cryptographic provider provides you some implementation of
known cryptographic algorithms (including RSA).

Exception (reported above) indicates you that Security System can't
find
any provider implementing RSA algorithm.

You can get a free provider (called BouncyCastle Provider)
from web at http://www.bouncycastle.org or .com (I don't remember).

Now you must proceeded in this way:

1. Add the jar file that you have downloaded from BC
   site (as indicated above) to your classpath.

2. Register BC provider dinamically into your Security
   System as below:
       Security.addProvider(new
         org.bouncycastle.jce.provider.BouncyCastleProvider());

3. Use RSA implementation provided by BC (Bouncy Castle)
   as follow:
   rsaCipher = Cipher.getInstance("RSA"); or explicity
   rsaCipher = Cipher.getInstance("RSA","BC");

I hope that my english is readable :-(

Hi,
GianpieroP