Sistem tanda tangan digital online untuk naskah dinas menggunakan algoritma DSA (Digital Signature Algorithm)

Abstract

Digital signature is the result of a cryptographic transformation from a message with a certain length of bits that can provide a mechanism to verify the origin authentication, data integrity, and non-repudiation of the signatories. The purpose of this study is to implement digital signatures on official letter using the DSA algorithm and test the execution time for the process of key pair formation, signature formation, and signature verification. Users of the system consists of three entities, namely employees, admin, and the certification authority. The development system was able to generate the private key and public key, generate a signature in the form of a compressed file (zip), and verify the signature and the public key along with the certificate. Functionality test of the system showed that 100% of the functions work is well. Execution time test concluded that the type and size of the official letter was not directly related to the execution time when the signatures were generated dan verified. Verification test of signature with specific scenarios showed that the signature file was not resistant to the attempt of re-extraction and re-compression.