What is Telnet?

Telnetting is the process of connecting to a remote server over the internet. In many ways, telnetting is analogous to making a phone call. When making a call you pick up the phone, dial a phone number, and then talk. Similarly, when telnetting you open a connection, type the correct Host Name, and then login. While telnetting you have a constant, direct connection to the server, and because you are going over the internet you can connect to any server in the world.

Teraterm Pro is the program for Windows95 which lets you do all this. Remote logins are efficient because they allow several people to simultaneously use one server from any computer connected to the Internet. Most people at Brandeis use Teraterm Pro to check their e-mail and to run programs on the mainframe.

What is SSH?

SSH stands for secure shell. It is a way of encrypting information that is passing between computers. Encryption is a method of disguising data so that no outsiders can read it. When using SSH, Teraterm Pro contacts the server and agrees on a method of encryption, after which all data sent is encrypted.

Why use SSH? In many ways the internet is like a large party-line. Although you may be "talking" to only one server, people can listen in on the information. This is especially critical when you are logging in and providing your password. At Brandeis this isn't as critical because the network has some built-in security, however this can be extremely important when connecting from anywhere or to anywhere outside of Brandeis. It is suggested that you use SSH even when telnetting completely within Brandeis.

Logging In With SSH

To start teraterm with SSH, as is suggested, double click on the Tera Term Pro icon within the Teraterm folder or choose Tera Term Pro from the Start menu (Start > Programs > Tera Term Pro). Teraterm will load and a new window will appear. If the window does not appear go to the File menu and choose New Connection. Make sure the TCP/IP button is pressed and fill-in the Host field with the host name. The host name is the full name of the server. For example, at Brandeis the host name for the undergraduate server is sam.undergrad.brandeis.edu or diane.undergrad.brandeis.edu. The servers you can connect to aren't limited to the ones at Brandeis. You can conceivably telnet to any server in the world as long as you know the host name. There are a number of host names already entered in Teraterm. By clicking on the arrow located to the left of the Host field you can choose from a number of preset host names. Later on in this document you will learn how to customize this list.

Below the Host field you should see three buttons labeled: Telnet, SSH, and Other. To use SSH make sure that the SSH button is pushed and that the TCP Port# is 22. If you ever want to turn SSH off, for instance if you need to connect to a server that doesn't support it, click the Telnet button. When you are done, click OK.

If you have never connected to this server before you might get a warning message. This message means that Teraterm can't verify that the server you are connecting to is a real server. If you are sure that the server is a legitimate server than you can ignore this message. To avoid getting the message in the future click the button which says "Add this machine and its key to the known hosts list" and then click Continue.

Otherwise, a new window will appear prompting you for your username and password. Fill in these fields, make sure the button "Use plain password to log in" is checked and click OK. You will now be connected to the server. If you look carefully you will notice that the teraterm icon located in the left, uppermost corner of the window has now changed into a computer over a key to let you know that you are connected to a secure server. To learn how to use your account once logged on please see the "Using Unix" documentation.