Stream cipher...
c = p OR k
* where c = chipertext, p = plaintext, k = key
- weakness: We can identify the key by XOR the ciphertext with plaintext
- same bit size for both key and message.
- example: 64 bit key for 64 bit data that be
c = p OR k
* where c = chipertext, p = plaintext, k = key
- weakness: We can identify the key by XOR the ciphertext with plaintext
- same bit size for both key and message.
- example: 64 bit key for 64 bit data that be
Block cipher...
example:
- data bit's size =356
- cryptography algorithm block = 256
so..
- 1st block contain 256 bit of data
- 2nd block contain 100 bit of data plus 56 additional bit to complete the block
example:
- data bit's size =356
- cryptography algorithm block = 256
so..
- 1st block contain 256 bit of data
- 2nd block contain 100 bit of data plus 56 additional bit to complete the block
DES (Data Encryption Standard)...
- 64 bit of data
- through 16 times of process
- while the key is changes each time through the process
- 56 bit of key + 8 bit of priority
- nowadays, it improved to become "triple DES" which 64 times of process during the encryption process
- 64 bit of data
- through 16 times of process
- while the key is changes each time through the process
- 56 bit of key + 8 bit of priority
- nowadays, it improved to become "triple DES" which 64 times of process during the encryption process
AES (Advance Encryption Standard)...
- also known as rijndael cryptography
- AES cipher has a 128-bit block size
- key sizes of 128, 192 and 256 bits
- also known as rijndael cryptography
- AES cipher has a 128-bit block size
- key sizes of 128, 192 and 256 bits