Quick question about Rijndael encryption

Hi,

Strictly speaking, this is not an ASP.NET question, but it is both germaine and quick (I hope).

I am encrypting and decrypting data using System.Security.Cryptography classes, specifically SymmetricAlgorithm with an AlgorithmName of Rijndael.  Seems to work great.

However, I notice that if I encrypt the exact same number several times, using the same key, the encrypted values are different.  Is this normal behavior? The different encrypted values all decrypt back to the correct identical values.

Thanks.

Dan
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