Page 336 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

network in cleartext, which is why administrators understand it
should not be used today. Some people suggest that using Telnet

within an encrypted VPN tunnel is acceptable, but it isn’t. Yes, the
traffic is encrypted from the client to the VPN server. However, it is
sent as cleartext from the VPN server to the Telnet server.

Secure Shell (SSH) is the primary protocol used by

administrators to connect to remote servers. Although it is possible
to use Telnet over an encrypted VPN connection, it is not
recommended, and it is simpler to use SSH.