Hybrid Cryptography and Steganography with Rivest Shamir Adleman and End of File Algorithm

Information security is very important, especially in technology and information exchange. This information will likely be spread to irresponsible parties in the file transfer process using the internet. Therefore, it is necessary to maintain the security of the information. Cryptographic techniques with the Rivest-Shamir-Adleman (RSA) algorithm can be used. However, the RSA algorithm still has weaknesses. That is, intruders can suspect it due to the scrambling of information. In this research, information security is carried out with cryptography and steganography to overcome these weaknesses. Steganography hides information by inserting files containing information into images with the End Of File (EOF) algorithm. In implementing the two algorithms, five processes are carried out: key generation, encryption, insertion extraction, and decryption. The computational time for applying the RSA algorithm to encrypt test files with an average difference in the number of characters takes 825 ms. Meanwhile, the decryption process takes an average of 781.2 ms with an average throughput of 221,470 Kbps. While the EOF algorithm on images with a resolution of 400x400 to 1200x1200 has an average Mean Square Error (MSE) value of 31,852 and an average Peak Signal Noise Ratio (PSNR) value of 45,929 dB, applying these two algorithms has a good security system.