What is the main advantage of using SSH over Telnet?

The main advantage of using SSH over Telnet is that SSH provides encrypted communication, enhancing security. Unlike Telnet, which transmits data, including usernames and passwords, in plaintext, SSH encrypts the entire session. This means that any data exchanged between the client and server is shielded from eavesdroppers, making it significantly harder for malicious actors to intercept sensitive information. The encryption aspect of SSH helps maintain confidentiality and integrity, which is critical in a network environment where security threats are prevalent.

While other options touch on features of SSH, they do not encapsulate the primary benefit regarding security. For instance, SSH's simplicity or speed relative to Telnet is not its defining characteristic; rather, it's the secure communication that is most important when choosing protocols for remote server administration. Additionally, while SSH does allow for file transfers through protocols like SFTP and SCP, those functionalities are secondary to the need for secure transmission of commands and data within a cyber environment.