COMMUNICATION DEVICE, ENCRYPTION COMMUNICATION SYSTEM, ENCRYPTION COMMUNICATION PROGRAM, AND ENCRYPTION COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a communication device, encryption communication system, program, and encryption communication method for reducing delay in data communication to a communication device of a communication partner.SOLUTION: A communication device which is connected to a relay device and can communicate with a communication device of a communication partner through the relay device determines whether or not communication speed required for encryption communication is equal to or higher than a threshold through a VPN configured with the communication device of the communication partner; executes encryption communication of data according to a predetermined protocol through a VPN configured with the relay device when it is determined that the communication speed is lower than the threshold; and executes encryption communication of data according to other than the predetermined protocol through the VPN configured with the communication device of the communication partner.