AES $ DES

Different between DES and AES


DES (Data Encryption Standard) and AES (Advanced Encryption Standard) both are the symmetric block cipher. AES was introduced to overcome the drawback of DES. DES has a smaller key size which makes it less secure to overcome this triple DES was introduced but it turns out to be slower. Hence, later AES was introduced by the National Institute of Standard and Technology. The basic difference between DES and AES is that in DES plaintext block is divided into two halves before the main algorithm starts whereas, in AES the entire block is processed to obtain the ciphertext.

DES (Data Encryption Standard) - This is a symmetric key block cipher that was adopted by National Institute of Standard and Technology in the year 1977. DES is based on the Feistel structure where the plaintext is divided into two halves. DES takes input as 64-bit plain text and 56-bit key to produce 64-bit Ciphertext.

AES (Advanced Encryption Standard) - This is also a symmetric key block cipher. AES was published in 2001 by the National Institute of Standards and Technology. AES was introduced to replace DES as DES uses very small cipher key and the algorithm was quite slower.

• In DES Plaintext is of 64 bits and in AES Plaintext can be of 128,192, or 256 bits. 
• DES in comparison to AES has smaller key size. AES has larger key size as compared to DES. 
• In DES the data block is divided into two halves. In AES the entire data block is processed as a single matrix. 
• DES work on Feistel Cipher structure.AES works on Substitution and Permutation Principle.
• DES has a smaller key which is less secure. AES has large secret key comparatively hence, more secure. 
• DES is comparatively slower. AES is faster.