How to: Create a nonce in C#

SQL Steve

Creating a nonce

Within the realm of cryptography, a nonce is a random value used to thwart replay attacks.  In other words, if a man in the middle intercepts the first message and tries to send that message again, the receiver will be able to identify that it is a duplicate message and discard it as the nonce should be different for each message submission.

The code below generates a 20 byte nonce for use in the OAuth 1.0a protocol.

private static string CalculateNonce()

{

    //Allocate a buffer

    var ByteArray = new byte[20];

    //Generate a cryptographically random set of bytes

    using (var Rnd = RandomNumberGenerator.Create())

    {

        Rnd.GetBytes(ByteArray);

    }

    //Base64 encode and then return

    return Convert.ToBase64String(ByteArray);

}

View original post