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 the protection key according to a start key signal;   generating the protection key according to the predetermined period; and   representing validity of the protection key indicating completion of the generation; and   encrypting data corresponding to the predetermined period with the protection key,   wherein the generating further comprises using selection of key in a size of 128 bit.   
     
     
         2 . The method of  claim 1 , wherein the encrypted data are in a block unit. 
     
     
         3 . The method of  claim 1 , wherein the 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 configured to schedule the key according to a predetermined period; and   a block round unit configured to encrypt the data units corresponding to the predetermined period by using the key,   wherein the schedule unit further is configured to initialize generation of the key according to a start key signal, to generate the key according to the predetermined period, to represent validity of the key, the validity indicating completion of the generation,   wherein the key is generated selectively in a set of keys, each of the keys being in a size of 128 bits.   
     
     
         5 . The apparatus of  claim 4 , wherein the block round unit is configured to encrypt the data units in a block unit. 
     
     
         6 . The apparatus of  claim 4 , wherein the schedule unit schedules the key 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 data units 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, generates the key according to the predetermined period, and represents validity of the key, the validity indicating completion of the generation,   wherein the data processing unit generates the key selectively in a set of keys, each of the keys being in a size of 128 bits.   
     
     
         8 . The computing program product of  claim 7 , wherein the data processing unit schedules the key according to the start key signal in real time. 
     
     
         9 . The computing program product of  claim 7 , wherein the data processing unit encrypts the data units in a block unit.