While there is much debate about the security and performance of Advance Encryption Standard (AES), there is a consensus it is significantly more secure than any of the algorithms supported by IPSec implementations today. AES is available in three key sizes: 128, 192 and 256 bits, versus the 56 bit DES. Therefore, there are approximately 1021 times more AES 128-bit keys than DES 56-bit keys. In addition, AES uses a block size of 128 bits—twice the size of DES or 3DES. Hence, AES must be used to ensure the privacy of the IPSec tunnel. |