STelnet based on SSH2 provides secure remote access over an insecure network.
Large numbers of devices need to be managed and maintained on a network. You cannot connect each device to a terminal. When no reachable route exists between remote devices and a terminal, you can use Telnet to log in to the remote devices from the device that you have logged in to. Telnet provides no secure authentication mode, and data is transmitted in simple mode over TCP, which brings security risks.
STelnet is a secure Telnet service based on SSH connections. SSH provides encryption and authentication and protects devices against attacks, such as IP spoofing.
If the authentication, encryption, and key exchange algorithms used by an SSH client to log in to a device through STelnet are weak security algorithms, the device displays a message indicating that these algorithms are insecure and asking users to use more secure algorithms or upgrade the client.
You can run the display ssh client session command to check the authentication and encryption algorithms used by the SSH client or the display security risk feature ssh_client command to check the risk information and handling suggestions for the SSH client.