Apparatus for encrypting/decrypting real-time input stream

Abstract

Disclosed is an apparatus for encrypting/decrypting a real-time input stream. The present invention includes a control unit, a key schedule unit, and a block round unit. Accordingly, the present invention realizes the encryption and decryption of AES algorithm in a manner of hardware, thereby enabling to carry out the encryption and decryption of the real-time input stream real-timely. And, the present invention finds the key for encryption or decryption of one block every round when realizing the encryption and decryption of the AES algorithm in a hardware manner, and then outputs the found keys to the block round unit. The present invention reduces the size of the key register required for the encryption/decryption of block data, thereby enabling to reduce a size of hardware as well as cost of product.

1 . A method of controlling a protection key of data, comprising: 
 scheduling the protection key according to a predetermined period, the scheduling comprising:    initializing generation of a protection key according to a start key signal;    generating the protection key according to the predetermined period; and    representing validity of the protection key, the validity indicating the completion of the generation; and    encrypting a first data corresponding to the predetermined period with the protection key,    wherein the validity further indicates that a second data is unencrypted.    
     
     
         2 . The method of  claim 1 , wherein the encrypted first data are in a block unit.  
     
     
         3 . The method of  claim 1 , wherein the first data are encrypted according to the start key signal in real time.  
     
     
         4 . An apparatus for controlling a key for encrypting or decrypting data units, the apparatus comprising: 
 a schedule unit scheduling the key according to a predetermined period; and    a block round unit encrypting a first data unit corresponding to the interval by using the key,    wherein the schedule unit initializes generation of the key according to a start key signal, generates the key in the predetermined period, and represents validity of the key, the validity indicating completion of the generation,    wherein the validity further indicates that a second data unit is unencrypted.    
     
     
         5 . The apparatus of  claim 4 , wherein the encrypted data unit is in a block unit.  
     
     
         6 . The apparatus of  claim 4 , wherein the first data unit is encrypted according to the start key signal in real time.  
     
     
         7 . A computing program product recorded in a readable medium, the computing program product comprising instructions operating to cause a data processing unit embodied in a machine to: 
 schedule a key according to a predetermined period; and    encrypt a first data unit corresponding to the predetermined period by using the key,    wherein the data processing unit initializes generation of the key according to a start key signal, generate the key in the predetermined period and represents validity of the key, the validity indicating completion of the generation, according to the instructions,    wherein the validity further indicates that a second data unit is unencrypted.    
     
     
         8 . The computing program product of  claim 7 , wherein the encrypted data unit is in a block unit.  
     
     
         9 . The computing program product of  claim 7 , wherein the first data unit is encrypted according to the start key signal in real time.