Cryptography in (LSB) Method Using RC4 Algorithm and AES Algorithm in Digital Image to Improve Message Security

Abstract

Cryptography and Steganography is the science and art in securing and maintaining the confidentiality of the message. However, to maintain the security and the confidentiality of a message it takes two different methods. To maintain the security of messages, the science that has been widely used is cryptography. As for maintaining the confidentiality ofthe message, the science used is steganography. But cryptography has weakness, the unknown messages is show us that the message is protected, that mean the unknown message show us it has a real message. So, we need to keep the confidentiality in the messages. For that we need a security message that can maintain the security and the secret ofthe message simultaneously. In this work to solve that problem, this study is combining between RC4 or AES algorithm in LSB Steganography. The test is done by calculating the length of the encryption time process and the decryption time process of each algorithm with the same number of messages and key lengths. Measurement time is done as much as 10 times, then taken average value to get consistent time because system instability. Therefore, we will compare the speed of encryption and decryption process by applying AES and RC4 algorithm to LSB. In the process of encryption and decryption, the AES algorithm is better in terms of speed compared to RC4 algorithm. The MSE andPSNR values generatedfrom the encrypted images based on the AES and RC4 algorithm doesn't show significant value. Overall the AES algorithm is better than RC4 algorithm when applied in LSB. This research show us that we can make double and triple secure only using same method and variant algorithms and different type ofobject such as Image, File, Audio or Others.