Secure transmission and storage of data in computer system are very important. DES algorithm which adopted by NBS as data encryption standard is very widely used method for data security.
DES algorithm has been used in link layer of computer network....
Secure transmission and storage of data in computer system are very important. DES algorithm which adopted by NBS as data encryption standard is very widely used method for data security.
DES algorithm has been used in link layer of computer network. In this case the algorithm is implemented by LSI Chip. But in the case of applying the algorithm to higher level layer in computer network, this algorithm should be implemented by software and the processing time is main concern in file processing for security.
In this paper DES algorithm is implemented in large computar IBM 3032 by assembly language and the processing time of five operational methods ECB, CBC, CBF, CFB, OFB are compared. Finally error characteristics is also compared among five operational methods.