Telnet: When PPP |
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by Eb Guenther |
Ask about setting up a web page and somebody will always say, "telnet to `this or that' and do `such and such'." Then `somebody else' always asks, "what's telnet?" Actually, `somebody else' hardly ever asks, because most of us don't want to be caught asking dumb questions, so we don't ask the question — just in case it's dumb.
So here's the answer to the question about telnet, `cause it wasn't a dumb question after all. Few questions ever are — though there are a lot of smart-alec answers. In the article I assume that if you only could get your hands on "telnet", whatever that is, and use it to get to `this or that' you'll know how to do `such and such'. So here are the three things you need to know about "telnet": What it is, where to get it, how to use it.
Telnet stands for the concept of issuing commands on a remote connection via a network; the name is derived from "tele" (remote) and net (network). First you create a network connection to an ISP (Internet Service Provider), such as HALNet, using PPP. Then you use that network to "telnet" to a remote computer — this could even be HALNet, which is remote to your PC, after all — and anything you type on your keyboard will affect what happens on that remote computer. In other words, telnet changes your powerful desktop PC from an intelligent machine into a "dumb terminal" to another computer, such as HALNet, so you can type commands on your keyboard and send the keystrokes directly to that remote computer, so that those commands can be executed there, instead of your own PC. With this terminal connected to HALNet, for example, you can now issue commands to HALNet within the limits of your Shell account.
Shell is just a fancy name for keeping multiple users on a single computer from running into each other and into the operating system. You know, like the shell game, except there's a pea under every shell. The telnet program is very much like the DOS window in Windows, except that this window opens to another computer. So an account which gives you command line access to a computer is called a shell account.
Why all the fancy footwork to reach HALNet? Why not just log in to the shell directly, when you dial up?
Your account was set up initially as a PPP account. When you dialup to HALNet, the modem connects you to your default account type, which is PPP. To use your shell account you can "telnet" back to HALNet.
The reverse is not possible. If you changed your default account type to Shell, you would no longer be able to do PPP, because PPP does not work from the command prompt of a Shell account. To get both, you have to use PPP first, because you can telnet over PPP, but you cannot PPP over telnet.
Unix is a four letter word.
I read this somewhere, can't remember where, but it describes perfectly what Unix means to most of us. Don't let that scare you off. The command line on the remote computer I mentioned above is on a Unix box (a PC running Unix as operating system). While I'm not going to go into Unix commands here (remember — you were expected to know how to do `such 'n such' <grin>), I am going to give you the one Unix command that should find any other available Unix command on a well-set-up system:
"apropos <topic>"
This (without the quotes or brackets!) will return a list of commands related to <topic>. For example,
apropos directory will return the following when issued at the HALNet prompt, and hopefully your Unix system as well (Unix gives brief descriptions following each result, which I have deleted to save space):
$ apropos directory
installit(1) — description deleted
basename(1), dirname(1)
cd(1)
chdir(2), fchdir(2)
chroot(2)
chroot(8)
. . .
unlink(2)
whois(1)
$
Throw out all those answers that have a number greater than "1" in the parentheses, and you're left with the user commands to choose from, and a description of what they do. One other command you may want to remember: "exit" (so I lied about `only one command') . If you do not use "exit" from HALNet, it may take HALNet a while before it realises that you disconnected. And it will NOT let you log in twice.
OK, one more Unix command _ man, short for manual. This is the other one command you cannot do without.
Once you have found a useful Unix command with apropos, you can look it up in more detail using "man <command>". For example, "man cd" will give you the online manual pages for "cd".
If you want more information about Unix you may want to buy a book. I personally prefer to use a reference book, and have frequently recommended "Unix in a Nutshell", O'Reilly Books. Unfortunately O'Reilly is privately owned, and I have been unable to buy stock in the company, so hold off on buying that book until they DO go public. Look for the blue cover, "System V" rather than the purple "SCO" book. It's closer to the "BSD" system HALNet uses.
Sorry about the alphabet soup. Back to HALNet, and telnet.
If you have Windows 95 you already have telnet. It came on the CD and should be installed in the Windows directory. See how to use it below.
For Windows 3.x you'll have to get telnet yourself. Fortunately there are a bunch of telnet clients available on the net. A couple of fair to good ones are even free. Here are two choices for you: trmptel.exe, an unsupported application from Trumpet Software, with few bells and whistles, can be found packaged with a bunch of other neat tools in: ftp://ftp.trumpet.com/winsock/winap21f.zip .
Another free client, the one I use, comes from Sweden. "EWAN" has more features than Trmptel, and can be found at: http://www.lysator.liu.se/users/zander/ewan.html .
The Windows 95 telnet should already be installed as part of the Network package. If not, search the CD for "telnet".
Windows 3.x telnet clients must be installed first.
For trmptel.exe expand the winap21f package to a temporary directory, and move "trmptel.exe" to the directory of your choice. Optionally, create an icon for it in the Program Manager. By the way, it's ok to rename it to telnet.exe, if you like.
Ewan comes with its own install program, which asks you where to install it, moves files, and creates an icon for you. Unzip the ewan zip file into a temporary directory, run INSTALL.EXE, and when asked tell it your directory of choice.
All three (W95 telnet.exe, trmptel.exe and ewan.exe) can be run from the RUN dialog window as follows:
Each client also lets you enter the target host from within (explore the menus of these programs to find how).
Ewan does this from a menu list of frequently visited hosts, which you set up, from which to choose a connection. To set up a menu choice for telneting to HALNet for example:
At this point you can click OK to connect to HALNet. Or use your Web browser to find other neat places to telnet to. One way to start is with Yanof's List. Search the web for Yanof. Or is it Yanoff? Check his list for telnet sites, and try them out.
In a future article I may report on how to use "telnet" to handle your e-mail from the far corners of the world. But the adventurous among you might try to telnet to HALNet and run "pine" without waiting for that to happen. One bit of advice, though: If there is any important e-mail waiting for you, don't deal with it in Pine until you know what to expect. You have been warned. And my liability only extends to the amount of money you paid for my services. ;-)
Surf's Up!
Eb Guenther is a HAL-PC member, founder of the Internet SIG and one of the founders of HALNet. He can be contacted on his web site at http://www.guenther.com.
E-mail me at webmaster@hal-pc.org with any comments you have and tell me what you want to see here.
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