Method and apparatus for controlling key sequence in sequency code encrypting system

Abstract

The present invention relates to serial cipher technology in enciphering and cipher, and has the main content of creating and buffer storing cipher sequence for serial enciphering process in advance. The technological points include: using one cipher key buffer memory for storing cipher key sequence; creating cipher sequence in advance and storing in the cipher key buffer memory; and responding the enciphering request to encipher data through obtaining complete or partial cipher key sequence from the cipher key buffer memory. In this way, the job of data enciphering with serial cipher is dispersed in the whole system operation period and the enciphering is completed through simple XOR operation after enciphering request.

Description

technical field [0001] The present invention relates to encryption, in particular to a method and device for controlling key sequences in a sequence cipher encryption system. Background technique [0002] Encryption is the transformation of data so that it is unintelligible or incomprehensible to anyone other than the intended recipient. One method of encrypting digitized data is to use a sequence cipher (or stream cipher, stream cipher). Usually, sequence cipher combines data and key sequence (or key stream, keystream; or encrypted bit stream, encryption bit stream) together by exclusive-or (exclusive-or, XOR) operation to obtain ciphertext (ie , encrypted data). Decryption is the process of generating the same key sequence as the sender and removing the key sequence from the encrypted data. If the XOR operation is performed when the sender encrypts the data, the same XOR operation is also performed when the receiver decrypts the data. [0003] Serial ciphers are widely...

AI Technical Summary

Problems solved by technology

However, after the overall cost of the sequence cipher encryption process has been determined, the contention of other applications in the system for system resources will make the sequence cipher encryption function take longer to complete the encryption (for example, when the sequence cipher encryption function and other applications functions share the same system resources), or additional waiting has to be introduced due to the larger bandwidth generated by the data to be encrypted (for example, when the serial cipher encryption function uses different system resources from other application functions or uses separate resources, but generates when the bandwidth of the key sequence is lower than the bandwidth of the data to be encrypted)

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