Question

Hai guys,
I hve a web page that has to send an encrypted value to another page in my asp.net web application… I want to know

• what is the best method to encrypt and decrypt a value using c#?

Answer 1

If by efficient you mean efficient development (not implementing your own solution), I would say using the algorithms in the System.Security.Cryptography namespace. If instead you mean least-CPU-intensive, then probably rot 13 as mentioned by Matt Ellen. (Edit: As others have mentioned, rot 13 is not secure. Please consider that carefully.)

Between DES, 3DES, RC2, and Rijndael, this is what MS has to say:

With small data, we find that
Rijndael, an AES (Advanced Encryption
standard), is the fastest of all the
methods. It has a variable block
length and key length, which may be
chosen to be any of 128, 192, or 256
bits. It also has a variable number of
rounds to produce the cipher text,
which depends on the key length and
the block length.