SSH (Secure Shell) is the correct answer because it's a protocol that provides a secure channel over an unsecured network for client-server communication, ensuring strong encryption and integrity of data. Telnet transmits communications in plaintext, making it susceptible to interception and eavesdropping. Console and AUX are not protocols but physical interfaces usually used for local device management, and their traffic encryption would depend on the overall security configuration of the network devices and the terminal software used.