Telnet

Zen and the Art of the Internet

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 Telnet
 
Telnet is the main Internet protocol for creating a connection
with a remote machine.  It gives the user the opportunity to be on one
computer system and do work on another, which may be across the street
or thousands of miles away.  Where modems are limited, in the majority,
by the quality of telephone lines and a single connection, telnet
provides a connection that's error-free and nearly always faster than
the latest conventional modems.
 
Using Telnet
 
As with FTP (Anonymous FTP), the actual command for negotiating a telnet
connection varies from system to system.  The most common is
telnet itself, though.  It takes the form of:
 
telnet somewhere.domain
 
To be safe, we'll use your local system as a working example.  By now,
you hopefully know your site's domain name.  If not, ask or try
to figure it out.  You'll not get by without it.
 
To open the connection, type
 
telnet your.system.name
 
If the system were wubba.cs.widener.edu, for example, the
command would look like
 
telnet wubba.cs.widener.edu
 
The system will respond with something similar to
 
Trying 147.31.254.999...
Connected to wubba.cs.widener.edu.
Escape character is '^]'.
 
The escape character, in this example ^] (Control-]), is the
character that will let you go back to the local system to close the
connection, suspend it, etc.  To close this connection, the user
would type ^], and respond to the telnet> prompt with the command
close.  Local documentation should be checked for information on
specific commands, functions, and escape character that can be used.
 
 Telnet Ports
 
Many telnet clients also include a third option, the port on
which the connection should take place.  Normally, port 23 is the
default telnet port; the user never has to think about it.  But
sometimes it's desirable to telnet to a different port on a system,
where there may be a service available, or to aid in debugging a
problem.  Using
 
telnet somewhere.domain port
 
will connect the user to the given port on the system
somewhere.domain.  Many libraries use this port method to offer their
facilities to the general Internet community; other services are also
available.  For instance, one would type
 
telnet martini.eecs.umich.edu 3000
 
to connect to the geographic server at the University of Michigan
(Geographic Server).  Other such port connections follow the
same usage.