Here is an intro to two common internet protocols using the ubiquitous telnet. This shows how to read your e-mail and news with telnet using the POP3 and NNTP protocols respectively.
You may be wondering what the point of this article is, especially since many of you are already using web-based e-mail accounts. Well, for one thing, this method lets you "get under the hood" and get more acquainted with the protocols that make e-mail and news work, but, there are some other uses to it as well.
POP
Accessing mail via telnet is more secure than reading your e-mail with a browser or client such as Outlook, especially since those programs can be exploited to spread e-mail viruses. Logging in to an e-mail server using a web browser is a potential risk- the browser may cache your login information. Using telnet is safer because you are reading all messages directly on the server prior to downloading them to your computer, giving you the opportunity to spot any suspicious messages before they arrive on your PC.
For example, if you are the victim of a mailbomb attack, you can use telnet to quickly and efficiently get rid of all the unwanted and unsolicited e-mails without having to waste time and bandwidth downloading them all first. There are also other benefits as well, but you will discover them as you learn, so let's move on to the tutorial itself.
First of all, get to your command prompt and type "telnet" without quotes to begin. Once in telnet, type open pop3.yourserver.com, obviously substituting your server's address. Note that although the default POP3 port is 110, most ISPs have a machine set up specifially for POP3 (as denoted by the pop3 in the first part of the address.) Therefore, you should automatically be connected to the POP3 server. Upon a successful connect, you will see something similar to the following:
+OK POP3 [212.87.3.19] v7.60 server ready
Now you're ready to login. Type "user username" without quotes and substituting "username" for your own username, and if you did it correctly, the server should respond with:
+OK Username accepted. Enter Password
From here, type "pass yourpass" and if you did it correctly, the server will reply with:
+OK Mailbox Open, x messages (x being the number of messages in
your mailbox.)
From here on out it is just as simple as before. Type "list" to see a list of messages. Each message is assigned a number. To read a message, type "retr#", where "#" is the number of the message you wish to read, and "retr" is "retrieve". To delete a message, simply type "dele#" again with the message number instead of a #. When you're done, simply type "quit". That's all there is to it! Next up usenet/nntp.
NEWS/USENET
First, go to your MS-DOS command prompt and open telnet. You will now be taken to the telnet prompt. Type the following:
open "news.wherever.com" 119
Obviously substituting "news.wherever.com" with the address of the host you desire to connect to. The port number for USENET is 119. If all goes well, you should see something similar to the following:
200 NNTP Service 5.00.0984 Version: 5.0.2195.4386 Posting Allowed
You are now in the news server. Here is a list of commands that can be used and a description of each (note that commands are case-sensitive):
LIST--Displays a list of newsgroups on the server
GROUP --Moves to a particular group
HEAD --Displays the header of a specified article
BODY --Displays the body of a specified article
ARTICLE --Displays a specified article
NEXT--Moves to the next article
POST--Posts a new article to the group
HELP--Brings up the servers "Help" screen
LAST--Moves to the previous article
QUIT--Exits the news server
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