TELNET

We have already seen that when you sit down at a terminal and log onto MCM, you are connected to a computer which is actually in a different room, or even building. Using TELNET it is possible to connect, the same way, to a computer in a different state or even country. TELNET allows "remote access" to computers around the world.

Understanding this probably requires some modification of the way you think about things. When most people thing of a "computer" they are thinking of a desktop PC, with a monitor, a CPU and a keyboard. "Computer" in the Internet sense of the word is usually more of a nondescript box sitting in a closet somewhere with a dozen or a hundred terminals connected to it. So you never really "sit down at the computer" you sit down at a terminal, the computer is somewhere else. When using the Internet, you can often TELNET to any machine elsewhere on the network as though it were right next to you. Perhaps an example is in order. I actually have accounts on three different computers--MCM, one in Florida, one in North Carolina. Using Telnet I can connect to whichever I want to use--just as if it were just down the hall.

Now, you might be saying "This is great, but I only have the one account. I don't need to access a remote computer. Here is where things get good -- many places have services set up that people can TELNET to much in the same way as anonymous FTP works. Many libraries have their card-catalogues "on line." Many of these are on the Internet. So for what it's worth, you can TELNET to the University of Miami and see if they happen to have a copy of Dr. Mitchell's book, Less Than Words Can Say. Savitz library is on-line, and you can TELNET there to see if they have the particular book that you're looking for. We'll TELNET to the Savitz library as an example.

There are two ways to start up the TELNET program and tell it what to connect to. The first (and easiest way) is to type

telnet computer.to.telnet.to at the $ prompt. This will promptly take you to where you want to be. The second way is to start the TELNET program by typing

telnet at the $ prompt. When TELNET has loaded, your prompt will look like this

telnet> and from this prompt you can type

open computer.to.telnet.to to access whatever computer you're looking for. You could also type

quit to get back to MCM's friendly $ prompt.

As an example, we will look at a TELNET session which will connect us to the SAVITZ library at Rowan college in New Jersey. Typing

telnet heroes.rowan.edu will initiate the session. The computer will respond with something like

trying 150.250.1.15
connected to HEROES
Escape character is '^^'

Rowan College of New Jersey Administrative VAXcluster

Welcome to OpenVMS v6.0

      Username: SAVITZ
        Last interactive login on Thursday, 30-DEC-1993 22:31

      System Login procedure 30-DEC-1993 22:32:45.61

      User Login Procedure 30-DEC-1993 22:32:46.45
        This is node HULK

It is technobabble like this that keeps computer consultants in business. There are only really two things here of any immediate merit, the first is to notice that the "escape character" is "^^" (the first carrot, ^ stands for ctrl, and the second ^ is SHIFT-6 btw) and the second is the Username prompt. The "escape character" is what we would type to end the TELNET session and get us back to MCM. Remember, the TELNET program itself is running on MCM, so any keystrokes that we type are seen by TELNET first. The escape character is usually ^^, (CTRL-SHIFT-6) which is because it is a key combination which is hardly ever used in any other program, so there would be no legitimate need to type it somewhere else. If the escape character were something like ^Z, something that gets used a lot, people would never be able to TELNET anywhere.

The Username prompt is important because it demonstrates how facilities will often set up "special services" you can access via TELNET. You might see a pointer in USENET that says "TELNET to quark.ork.foo and login as SPAM to access this way-cool service."

Many TELNET services will include a "port address" which is an additional number after the computer's name. The "port" allows a facility to set up numerous services which can be reached through the specification of this unique address. TELNETting to port 79 on most computers will give you the equivalent of a FINGER command for example.

TELNET allows you to access many different types of services such as MUD's, Libraries, and Information databases. For example:

The PENpages: a database maintained by Penn State University. There's all sorts of interesting information here, weather, agricultural info, etc. TELNET to psupen.psu.edu and log in as PNOTPA.
Geographic Name Server: a database which contains census (1980 at last check) info on American cities. You can search by town name, by zip code and a few other ways. It'll tell you that Elmer has 971 people living in it. Way cool. TELNET to martini.eecs.umich.edu 3000.
Food and Drug Administration BBS.: You can look over congressionaltestimony, AIDS info, or news on recent FDA approvals. TELNET to fdabbs.fda.gov and log in as BBS.
Ham Radio Operators.: Who the heck is N2FDV? Well, you can TELNET to callsign.cs.buffalo.edu 2000 and find out. This service gives you names, addresses, and call signs of Ham Radio operators.
This is only a skeletal example of what is out there. You can find more in various Internet guides or on USENET. The Yanoff List of Special Connections is kept current and posted to the USENET group news.answers.

Search Feedback