Implementation of AES and ECDSA for Encrypted Message in Instant Messaging Application

Instant messaging was one of the communication technologies that were widely used by the public. The amount of mobile instant messaging users could open up crime opportunities, including message sabotation. The use of cryptography was one of the right methods to maintain data or information security while a communication occurred. Message security was done by combining a symmetric encryption algorithm with a digital signature algorithm. Combination of AES and ECDSA is done as a method of securing messages. AES is used for message encryption, ECDSA is used as an identifier for the sender of the message. Confidentiality and data integrity is guaranteed through encrypting messages in the database and with carrying out digital signatures.