Teknik Signcryption untuk Pengamanan Berkas Digital dengan Algoritma Multi-Factor RSA dan Algoritma Esign

Abstract

The modern digital era has made cryptography a tool capable of solving problems of confidentiality, authentication, integrity and non-repudiation. Encryption can solve the problem of message confidentiality and digital signatures can solve the problem of message authentication. The conventional method is to encrypt the message and then digitally sign it or vice versa. However, this method requires large computing and communication costs. Signcryption is a new way of encrypting digital signatures without requiring large computing and communication costs. This research uses the RSA Multi-Factor algorithm as encryption and the ESIGN algorithm as a digital signature. This research was carried out by comparing two Signcryption technique schemes, namely encrypt-then-sign and sign-then-encrypt to determine which scheme is better in terms of time performance. Example of comparison time results for testing algorithm calculations based on the bit length of 8 bit and 16 bit prime numbers. The sign-then-encrypt signcryption scheme has a time speed of 0,0132 seconds and 0,0136 seconds. Meanwhile, the encrypt-then-sign signcryption scheme has a time speed of 0,0164 seconds and 0,0203 seconds. This research also tested prime number bit lengths of 1024 bits and 2048 bits and plaintext character lengths of 100 and 1000. From the two signcryption schemes, it can be concluded that the best scheme in computing time is the sign-then-encrypt scheme.