“Every time we telnet into a remote machine the connection data
will cross the local network, giving an eventual intruder the
possibility to spy the connection and eventually insert some
malicious commands into the data flux. The use of some strong
cryptography systems will allow an enormous improvement in the
security of the net.”
“From the manual page of ssh we can learn that: “Ssh (Secure
Shell) is a program for logging into a remote machine and executing
commands in a remote machine. It is intended to replace rlogin
and rsh, and provide secure encrypted communications between two
untrusted hosts over an insecure network. X11 connections and
arbitrary TCP/IP ports can also be forwarded over the secure
channel”. It is a powerful, very easy-to-use program that uses
strong cryptography for protecting all transmitted confidential
data, including passwords.“
“At present time there are two SSH protocol, referred as SSH2
and SSH1, the first one being an improvement of the SSH1 protocol.
SSH2 now supports other key-exchange methods besides
double-encrypting RSA key exchange. The current distribution comes
with Diffie-Hellman key exchange and has support for DSA and other
public key algorithms besides RSA.”