Telnet FAQ

Telnet Frequently Asked Questions

What is telnet?
Telnet and its close cousins rlogin and tn3270 are methods of connecting to a remote computer over the Internet that let you use programs and data just as if you were using the computer locally. Do not confuse telnet with Telenet, the old name for Sprintnet.

Telnet is a text-only protocol. At one time it was one of the most common ways to connect to other sites. Now with the growth of the web, it is hardly used. There are still a few sites and resources that can only be reached through telnet.

What can I use telnet for?

• If you are a gamer, there are a number of text based games still available through telnet.
  
• Outside of games, unless you already know of a particular use, such as connecting to a particular government database, you probably have no use for it.
  
  
• For years, many library catalogs were only reachable through telnet. Many early community resources, called free-nets, were reachable through telnet. You would have trouble finding any of these now.
  
  
• Delphi's Internet service, the first nationwide Internet service available to the public, closed its telnet access on April 30, 2001.

How can I connect to a telnet address of my choosing?
If your Internet provider supports telnet (not all do), you can connect to a telnet address in one of two ways:

• Recent versions of Windows include a command line telnet. Begin at Start/Run and type command. On the next screen, type your telnet command. From a SLIP or PPP or ethernet connected account: type a telnet URL into the location window of your browser. To do this, your browser must be configured with a supporting version of telnet software. Two good ones, better than the built-in command line telnet for Windows, are NetTerm and CRT.
  
  
• If you are using Windows95, make sure you get a version that supports Win95's 32-bit stack. Although Win95 comes with a version of telnet.exe, it is a bare bones version with no zmodem transfers, and there are much better ones available.
  
• A telnet URL takes this form: telnet://some.address:port-number. Most of the time, the port number will be the default 23. If so, it can be omitted.
  
  
• From a unix shell account or other account that lets you type telnet commands, you can issue a command like this: telnet some.address port-number

What is tn3270? How can I connect to a tn3270 site?
TN3270 is a special type of telnet that is sometimes needed to connect to IBM mainframe sites. Regular telnet will often work, but if you have trouble with keypresses and commands, you may need to get a tn3270 client to add to your software.

Can I transfer files through a telnet connection using zmodem or other methods?
It depends on the version of telnet you are using. Some support zmodem, kermit, etc., and some do not. If you do have a version of telnet that supports these transfer methods, it still depends on whether you are using a SLIP or PPP or ethernet account where you run the software or you are using a shell account and using the shell account's software. SLIP, PPP, and networked accounts should have no problem, but shell accounts are not always configured to support binary transfers. Transferring binary files through a shell account requires the remote site to be operating in 8-bit mode, and many shell sites do not. In special circumstances, if you have enough knowledge of the configuration and operating system of the remote site, for example unix, you may be able to reset the mode.

How do I configure telnet software for Netscape or MSIE?

• You configure telnet in Netscape 4.0 by selecting Edit/Preferences/Applications and scroll down to "URL: Telnet Protocol". Highlight it and click on the Edit button. Browse for the new software to complete the setup. Then when you enter a Telnet URL in the Netsite window, it will call up the application and launch it.
  
• Netscape 3.0 is configured by selecting Options/General Preferences, selecting the Apps tab, and filling in the Telnet Applications window.
  
• To set MSIE for your preferred telnet application, load Windows Explorer (not MSIE), click on View/Options/FileTypes. Scroll down to URL: Telnet Protocol, highlight, click Edit and Browse for the software.
  
• For tn3270 configuration with either version of Netscape or MSIE, follow the same steps, but select tn3270 in place of telnet.