-\versionid $Id: intro.but,v 1.4 2001/11/25 16:57:45 simon Exp $
+\define{versionidintro} \versionid $Id$
\C{intro} Introduction to PuTTY
network.
Multi-user operating systems, such as Unix and VMS, usually present
-a command-line interface to the user, much like the \q{Command
-Prompt} or \q{MS-DOS Prompt} in Windows. The system prints a prompt,
-and you type commands which the system will obey.
+a \i{command-line interface} to the user, much like the \q{\i{Command
+Prompt}} or \q{\i{MS-DOS Prompt}} in Windows. The system prints a
+prompt, and you type commands which the system will obey.
Using this type of interface, there is no need for you to be sitting
at the same machine you are typing commands to. The commands, and
responses, can be sent over a network, so you can sit at one
computer and give commands to another one, or even to more than one.
-SSH, Telnet and Rlogin are \e{network protocols} that allow you to
-do this. On the computer you sit at, you run a \e{client}, which
-makes a network connection to the other computer (the \e{server}).
+SSH, Telnet and Rlogin are \i\e{network protocols} that allow you to
+do this. On the computer you sit at, you run a \i\e{client}, which
+makes a network connection to the other computer (the \i\e{server}).
The network connection carries your keystrokes and commands from the
client to the server, and carries the server's responses back to
you.
These protocols can also be used for other types of keyboard-based
interactive session. In particular, there are a lot of bulletin
-boards, talker systems and MUDs (Multi-User Dungeons) which support
+boards, \i{talker systems} and \i{MUDs} (Multi-User Dungeons) which support
access using Telnet. There are even a few that support SSH.
You might want to use SSH, Telnet or Rlogin if:
able to access from somewhere else
\b your Internet Service Provider provides you with a login account
-on a web server. (This might also be known as a \e{shell account}.
+on a \i{web server}. (This might also be known as a \i\e{shell account}.
A \e{shell} is the program that runs on the server and interprets
your commands for you.)
-\b you want to use a bulletin board system, talker or MUD which can
+\b you want to use a \i{bulletin board system}, talker or MUD which can
be accessed using Telnet.
You probably do \e{not} want to use SSH, Telnet or Rlogin if:
\H{which-one} How do SSH, Telnet and Rlogin differ?
-This list summarises some of the differences between SSH, Telnet and
-Rlogin.
+This list summarises some of the \i{differences between SSH, Telnet
+and Rlogin}.
-\b SSH is a recently designed, high-security protocol. It uses
-strong cryptography to protect your connection against
-eavesdropping, hijacking and other attacks. Telnet and Rlogin are
-both older protocols offering minimal security.
+\b SSH (which stands for \q{\i{secure shell}}) is a recently designed,
+high-security protocol. It uses strong cryptography to protect your
+connection against eavesdropping, hijacking and other attacks. Telnet
+and Rlogin are both older protocols offering minimal security.
-\b Telnet allows you to pass some settings on to the server, such as
-environment variables. (These control various aspects of the
-server's behaviour. You can usually set them by entering commands
-into the server once you're connected, but it's easier to have
-Telnet do it automatically.) SSH and Rlogin do not support this.
-However, most modern Telnet servers don't allow it either, because
-it has been a constant source of security problems.
-
-\b SSH and Rlogin both allow you to log in to the server without
-having to type a password. (Rlogin's method of doing this is
+\b SSH and Rlogin both allow you to \I{passwordless login}log in to the
+server without having to type a password. (Rlogin's method of doing this is
insecure, and can allow an attacker to access your account on the
server. SSH's method is much more secure, and typically breaking the
security requires the attacker to have gained access to your actual
doesn't support SSH, it might be worth trying to persuade the
administrator to install it.
-If you are behind a good firewall, it is more likely to be safe to
-use Telnet or Rlogin, but we still recommend you use SSH.
+If your client and server are both behind the same (good) firewall,
+it is more likely to be safe to use Telnet or Rlogin, but we still
+recommend you use SSH.
projects / u / mdw / putty / blobdiff