unx09.htm

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<LI>

<A HREF="#I83">Signature Files</A></LI>

<LI>

<A HREF="#I84">Excessive Quoting</A></LI>

<LI>

<A HREF="#I85">Pyramid Schemes</A></LI>

<LI>

<A HREF="#I86">Excessive Crossposting</A></LI>

<LI>

<A HREF="#I87">Read the FAQ!</A></LI>

<LI>

<A HREF="#I88">Keep the Flaming to a Minimum</A></LI>

<LI>

<A HREF="#I89">Don't Bluff</A></LI>

<LI>

<A HREF="#I90">Whew!</A></LI></UL>

<LI>

<A HREF="#I91">USENET Miscellany</A></LI>

<UL>

<LI>

<A HREF="#I92">Creating a New Group</A></LI>

<LI>

<A HREF="#I93">How Can I Get That Person Off the Net?</A></LI>

<LI>

<A HREF="#I94">Recommend Some Newsgroups!</A></LI></UL>

<LI>

<A HREF="#I95">Watch Out for Pranks</A></LI>

<LI>

<A HREF="#I96">USENET Adieu</A></LI></UL>

<LI>

<A HREF="#I97">Talk</A></LI>

<LI>

<A HREF="#I98">Internet Relay Chat (IRC)</A></LI>

<UL>

<LI>

<A HREF="#I99">Basic IRC Structure</A></LI>

<LI>

<A HREF="#I100">Getting IRC Clients</A></LI>

<LI>

<A HREF="#I101">Connecting to a Server</A></LI>

<LI>

<A HREF="#I102">Choosing Channels</A></LI>

<LI>

<A HREF="#I103">Need Help?</A></LI>

<LI>

<A HREF="#I104">Bad Moves</A></LI>

<LI>

<A HREF="#I105">Further Info</A></LI></UL>

<LI>

<A HREF="#I106">Is That It?</A></LI></UL></UL></UL>



<H1 ALIGN="CENTER">

<CENTER><A ID="I1" NAME="I1">

<BR>

<FONT SIZE=5><A ID="I2" NAME="I2"></A><B>9</B>

<BR></FONT></A></CENTER></H1>

<H2 ALIGN="CENTER">

<CENTER><A ID="I3" NAME="I3">

<FONT SIZE=5><B>Communicating with Others</B>

<BR></FONT></A></CENTER></H2>

<H5 ALIGN="CENTER">

<CENTER><A ID="I4" NAME="I4">

<FONT SIZE=3><B>By Ron Dippold</B>

<BR></FONT></A></CENTER></H5>

<P>The Internet would be useful as simply a data-sharing device&#151;being able to FTP to another site and grab a program is quite useful, as is being able to log on to another machine using telnet. But there's a special type of data that comprises most of 

the appeal of the Internet&#151;person-to-person communication. You can talk with people around the world, a message at a time or even in real-time.

<BR></P>

<P>This chapter covers the following topics regarding communications:

<BR></P>

<TABLE BORDER>

<TR>

<TD>

<P>E-mail</P>

<TD>

<P>Electronic mail enables you to exchange messages with anyone who is a member of any of the major information networks. It's faster and cheaper than snail-mail (the Post Office), and it's often cheaper and more convenient than a phone call.</P>

<TR>

<TD>

<P>USENET</P>

<TD>

<P>Whereas e-mail is person-to-person messaging, USENET is person-to-millions-of-persons messaging on literally thousands of different topics. This is more information per day than any person can read completely, even if all they did was read it.</P>

<TR>

<TD>

<P>Talk</P>

<TD>

<P>Simple person-to-person chat.</P>

<TR>

<TD>

<P>IRC</P>

<TD>

<P>Internet Relay Chat is a multiple-person discussion forum, much like a CB radio channel. It is reportedly more addictive than drugs.</P></TABLE>

<H3 ALIGN="CENTER">

<CENTER><A ID="I5" NAME="I5">

<FONT SIZE=4><B>Electronic Mail (E-Mail)</B>

<BR></FONT></A></CENTER></H3>

<P>E-mail is one of the most important applications of the Internet as far as companies, schools, and government agencies are concerned. Since these are the entities that heavily influence Internet development by deciding to hook up and offer Internet to 
their members, it's often considered one of the most important (if not the most important) service the Internet offers. For major online services such as CompuServe, GEnie, or SprintMail, which offer their users access to the Internet for mailing purposes, 

it's the only Internet service.

<BR></P>

<H4 ALIGN="CENTER">

<CENTER><A ID="I6" NAME="I6">

<FONT SIZE=3><B>Basic Concepts</B>

<BR></FONT></A></CENTER></H4>

<P>The basic principle behind e-mail is simple. You write a message using your computer, send it to another computer user, and it appears on that user's computer, where the user reads it. You probably know from experience that composing the letter is not a 

major technical chore, nor is reading it. The first problem is the same one you encounter with all computer data&#151;organizing your data, in this case e-mail. The second problem is how to format the information&#151;how do you send a program by mail? The 

third problem, which is far larger, is exactly how you get your message from your machine in Walla Walla, Washington, United States, to your friend's computer in Reykjavik, Iceland. And, since he's probably sharing his Internet computer with other people, 

how you get it to his account.

<BR></P>

<H5 ALIGN="CENTER">

<CENTER><A ID="I7" NAME="I7">

<FONT SIZE=3><B>Internet Mail Is More Than Internet</B>

<BR></FONT></A></CENTER></H5>

<P>The Internet proper is composed of computers tied together at all times by direct links. If your computer is &quot;on the Internet&quot; and my computer is &quot;on the Internet,&quot; our machines should be able to exchange data without any dialing 
involved.

<BR></P>

<P>If you think about messages, however, you'll see that individual messages are transferable between machines that connect only occasionally. Each machine can save up messages that need to be sent, then exchange messages when they connect. Bulletin board 

systems (BBSes) do this routinely. This concept is exploited by many systems that offer &quot;Internet Mail&quot;&#151;the systems can exchange e-mail with other Internet sites even though they are not part of the Internet itself. They do this by 
occasionally connecting to a system that is really on the Internet and exchanging mail. This is an important concept.

<BR></P>

<P>A computer system does not actually have to be part of the Internet to offer Internet Mail access. Since true Internet access is expensive, if you need only e-mail access you will be able to obtain it much more cheaply than true Internet access. There 
is probably at least one BBS in your area that offers Internet Mail access cheaply, sometimes even for free.

<BR></P>

<P>Mail will be slower on such systems. Since they only connect to a true Internet machine occasionally (maybe only once a day), all your outgoing mail and any incoming mail for you is held until this occurs. This introduces a delay of several hours. Since 

the delivery time for e-mail from one Internet machine to another is often measured in minutes, this is a substantial difference. If you want more, you pay more.

<BR></P>

<H5 ALIGN="CENTER">

<CENTER><A ID="I8" NAME="I8">

<FONT SIZE=3><B>E-Mail Is Text</B>

<BR></FONT></A></CENTER></H5>

<P>As far as Internet is concerned, e-mail is plain text, nothing more: This means all letters a through z, numbers 0 through 9, and various punctuation. You can't just send a program using e-mail. Various computers along the way will almost certainly 
eliminate over half of the message, if it gets transferred at all.

<BR></P>

<P>This imposes certain limitations&#151;if you want to do anything special, such as carry other information about the message other than just the basic content, you have to do it within this constraint.

<BR></P>

<H5 ALIGN="CENTER">

<CENTER><A ID="I9" NAME="I9">

<FONT SIZE=3><B>E-Mail Formats</B>

<BR></FONT></A></CENTER></H5>

<P>A message from you to another person will probably travel through several machines. Typically, mail from your computer goes to the mail computer for your site, then to your service provider's computer, then to a large &quot;backbone&quot; site. From 
there it goes to another backbone site, to the recipient's service provider, to the recipient's site, then to the recipient's computer. Obviously, you need some way of addressing mail to a specific person&#151;just sending mail to &quot;John Smith&quot; 
isn't going to work.

<BR></P>

<P>You need some delivery information to go along with the message, but you don't want to modify the vital contents of the message. If you're sending the latest Lorena Bobbitt joke to a friend, you don't want a piece of it chopped off (or otherwise 
modified).

<BR></P>

<P>On the Macintosh, a similar problem is solved by splitting a file into its Resource and Data forks. OS/2 uses extended attributes. You can't do this with the Internet, because e-mail is text only, by definition. You get around this problem by defining 
every piece of e-mail to consist of two basic pieces&#151;a header and a body.

<BR></P>

<P>Internet mail consists of a header and a body. The header comes first, and contains all the information about the message, such as who it came from and who it's for. The end of the header is given by a completely blank line&#151;not even any spaces. The 

body of the message, which consists of the actual message content, follows.

<BR></P>

<P>Actually, a message can consist of a header only. This isn't usual, but it's common enough, usually due to user error, that you shouldn't be surprised to see it.

<BR></P>

<H5 ALIGN="CENTER">

<CENTER><A ID="I10" NAME="I10">

<FONT SIZE=3><B>E-Mail Addressing</B>

<BR></FONT></A></CENTER></H5>

<P>How do you get mail to a person on another computer, considering that the mail probably has to pass through several computers?

<BR></P>

<P>One way is to list the computers the mail should pass through with the recipient. This is done on the Internet by an almost obsolete format known as UUCP bang-path:

<BR></P>

<PRE>comp01!comp02!comp03!username</PRE>

<P>It's called a bang-path because of the exclamation points: bang! bang! bang! Computer people, UNIX types especially, love short names. Exclamation is four syllables, and bang is only one. Plus, it's easier to spell. Thus, a mail path delimited by bangs 

is a bang-path.

<BR></P>

<P>This indicates that you want the mail to pass successively through the computers known as comp01, comp02, and comp03. Once on comp03 it should go to user username. This type of addressing is simple if you know exactly where your mail is going, and it 
makes it easy for systems along the way to figure out where to send your mail next; but it is a crawling horror otherwise. Imagine if you had to address your snail-mail (post office) mail like this&#151;from my mailbox to my local post office, then the 
central office, then the regional office, then another regional office, then the central office, then the local office, then the recipient's mailbox. What if one of the offices along the way changes? Oh yes, the names of the offices can each be only six 
letters long (a UUCP host name limitation).

<BR></P>

<P>The post office uses a different concept&#151;each person is identified by country, state, city, and address. A parallel system for the post office (the ZIP code) makes sorting faster for humans, and it guards against sloppy writing causing too many 
problems. To get a message to someone from anywhere in the world, you just identify them with this information. You don't need to care about the path it takes to get there.

<BR></P>

<P>The more standard Internet version of this is domain name addressing, often just called Internet addressing. It looks like this:

<BR></P>

<PRE>localname@domain</PRE>

<P>Both pieces are extensible, although localname is usually just your user ID. The domain is read from right to left and specifies a series of progressively smaller logical domains (such as country, state, city, then street address). Here's an example:

<BR></P>

<PRE>[e-mail]</PRE>

<P>The far right of the domain, com, indicates that this is a commercial site. The period separates it from the next item in the domain. hugeco is the name of the entity, in this case HugeCo, Ltd. sales specifies a specific department or site within the 
entity. Finally, wubba is the specific computer within the site.

<BR></P>

<P>This is known as a &quot;fully-qualified domain name&quot;&#151;the address includes complete information on how to reach good old Joe Faceless, right down to the specific machine. Usually you don't have to be this specific. If there's only one 
jfaceless account within the company, for instance, HugeCo's mail computers should be smart enough to figure out how to route incoming mail to him. In this case, the Internet address he would proudly put on all his business cards would be this:

<BR></P>

<PRE>[e-mail]</PRE>

<P>Obviously, if [e-mail] sends mail to [e-mail], someone needs to figure out how to get it to him&#151;this is the province of domain name servers. Let these computers do the work, and you usually don't have to worry about it.

<BR></P>

<P>By Internet convention, capitalization in the domain name is ignored. So you could use HugeCo.Com, HUGECO.COM, or hugeco.com. They're all the same. The same thing should happen with the user name as well, but this is not required, and if the site is 
using poor software it may consider JFaceless and jfaceless to be different users. It's safest always to preserve the case.

<BR></P>

<P>The far-right component of the domain is known as the top-level domain name. The most common in the United States are edu (educational sites), com (commercial sites), gov (government sites), and mil (military sites). For other countries, the top-level 
domain is the two-letter ISO country code. For example, [e-mail] is a user in Germany. This isn't foolproof, as there are sites in Canada that don't bother with using the .ca code for Canada.

<BR></P>

<P>Sometimes you'll see something like this:

<BR></P>

<PRE>uuhost![e-mail]</PRE>

<P>This indicates that once the mail gets to the site ancient.edu some other form of addressing takes over. You usually see this when dealing with an ancient system, or when transferring mail with another network.

<BR></P>

<H4 ALIGN="CENTER">

<CENTER><A ID="I11" NAME="I11">

<FONT SIZE=3><B>E-Mail Headers</B>

<BR></FONT></A></CENTER></H4>