Encryption apparatus and method in a wireless communications system
AssigneeSamsung Electronics Co., Ltd.
InventorJong-Su Lim
Life of this patent
Estimating the term…
Abstract
An encryption apparatus and method for generating a ciphertext from an input plaintext of the same length as the ciphertext by parallel processing of the input signal. Since a non-delayed signal is synchronized to a delayed signal, an accurate ciphertext is produced. Therefore, the encryption speed is increased, the number of devices for timing synchronization is reduced, an encryption system is stabilized, and production cost is reduced.
Claims12
An encryption method for dividing a first plaintext bit stream of length 2n into first and second sub-bit streams of length n, dividing a second plaintext bit stream of length 2n into third and fourth sub-bit streams of length n, and generating a ciphertext bit stream of length 2n from the first, second, third and fourth sub-bit streams using 2-rounds of encryption, the method comprising the steps of:
- performing the first-round of encryption by encrypting the received the first and second sub-bit streams with predetermined first encryption codes an odd number of times and outputting first and second ciphertext bit streams, wherein the first ciphertext bit stream is encrypted a first number of times and the second ciphertext bit stream is encrypted a second number of times, the second number of times exceeding the first number of times;
- generating a first operated ciphertext bit stream by performing a logical exclusive-OR-operation on the first ciphertext bit stream and the third sub-bit stream;
- generating a second operated ciphertext bit stream by performing a logical exclusive-OR operation on the second ciphertext bit stream and the fourth sub-bit stream;
- and
- performing the second-round of encryption by encrypting the received first operated ciphertext bit stream and the second operated ciphertext bit stream with predetermined second encryption codes an odd number of times and concurrently outputting third and fourth ciphertext bit streams of length n, wherein the third ciphertext bit stream is encrypted a third number of times and the fourth ciphertext bit stream is encrypted the fourth number of times, the fourth number of times exceeding the third number of times,
- wherein the last encryption for the second ciphertext bit stream in the first-round is performed at the same time of performing the first encryption of the first operated ciphertext bit stream in the second round of encryption.
An encryption apparatus for dividing a first plaintext bit stream of length 2n into first and second sub-bit streams of length n, dividing a second plaintext bit stream of length 2n into third and fourth sub-bit streams of length n, and generating a ciphertext bit stream of length 2n from the first, second, third and fourth sub-bit streams using 2-rounds of encryption, the apparatus comprising:
- a first ciphering unit for receiving the first and second sub-bit streams, and generating first and second ciphertext bit streams of length n by encrypting the first and second sub-bit streams with predetermined first encryption codes KO1,1, KO1,2, KO1,3, KI1,1, KI1,2, and KI1,3 an odd number of times, wherein the first ciphertext bit stream is encrypted a first number of times and the second ciphertext bit stream is encrypted a second number of times, the second number of times exceeding the first number of times;
- an operating unit for generating a first operated ciphertext bit stream by performing a logical exclusive-OR-operation on the first ciphertext bit stream and the third sub-bit stream and generating a second operated ciphertext bit stream by performing a logical exclusive-OR-operation on the second ciphertext bit stream with the fourth sub-bit stream;
- and
- a second ciphering unit for receiving the first operated ciphertext bit stream and the second operated ciphertext bit stream comprising the predetermined time delay, generating third and fourth ciphertext bit streams of length n by encrypting the first operated ciphertext bit stream and the second operated ciphertext bit stream with predetermined second encryption codes KO2,1, KO2,2, KO2,3, KI2,1, KI2,2, and KI2,3 an odd number of times, and concurrently outputting the third and fourth ciphertext bit streams, wherein the third ciphertext bit stream is encrypted a third number of times and the fourth ciphertext bit stream is encrypted the fourth number of times, the fourth number of times exceeding the third number of times,
- wherein the last encryption for the second ciphertext bit stream in the first-round of encryption is performed at the same time of performing the first encryption for the first operated ciphertext bit stream in the second-round of encryption.
Dependencies are inferred from the claim text.