Symmetric algorithms always use the same key for encryption and decryption and they are fast for encryption and ecryption.
The next table lists symmetric algorithms supported by .NET:
Abstract Algorithm
Default Implementation
Valid Key Size
Maximum Key Size
DES
DES
DESCryptoServiceProvider
64
64
TripleDES
TripleDES
TripleDESCryptoServiceProvider
128,192
192
RC2
RC2
RC2CryptoServiceProvider
40-128
128
Rijndael
Rijndael
RijndaelManaged
128,192,256
256
The strength of the encryption corresponds …