Key Takeaways
TELNET doesn't have any encryption, so everything is transmitted in plaintext. SSH is encrypted, so it is private and secure. That's why SSH should be used in preference to TELNET.
SSH is vastly more secure than TELNET, which ought to be retired.
TELNET doesn't have any encryption, so everything is transmitted in plaintext. SSH is encrypted, so it is private and secure. That's why SSH should be used in preference to TELNET.