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<b>Linux</b></font><p>
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<UL>
<LI><A HREF="#Heading1">- 47 -</A>
<UL>
<LI><A HREF="#Heading2">Setting Up an Internet Site</A>
<UL>
<LI><A HREF="#Heading3">Connecting to the Internet</A>
<LI><A HREF="#Heading4">Services You Need</A>
<LI><A HREF="#Heading5">Direct Connection Through a Gateway</A>
<LI><A HREF="#Heading6">Connecting Through Another Gateway</A>
<LI><A HREF="#Heading7">Using a Service Provider</A>
<LI><A HREF="#Heading8">Summary</A>
</UL>
</UL>
</UL>
<P>
<HR SIZE="4">
<H2 ALIGN="CENTER"><A NAME="Heading1<FONT COLOR="#000077">- 47 -</FONT></H2>
<H2 ALIGN="CENTER"><A NAME="Heading2<FONT COLOR="#000077">Setting Up an Internet
Site</FONT></H2>
<P><I>by Tim Parker</I></P>
<P>IN THIS CHAPTER</P>
<UL>
<LI>Connecting to the Internet
<P>
<LI>Services You Need
<P>
<LI>Direct Connection Through a Gateway
<P>
<LI>Connecting Through Another Gateway
<P>
<LI>Using a Service Provider
</UL>
<P>Linux is well-suited for connecting to the Internet and for using many of the
Internet services. This chapter looks at the ways you can connect to the Internet.
The following chapters in this section show you how to set up your Linux system as
a server for four popular services.</P>
<P>If you only want to use your Linux system to access other servers, you don't have
to worry about any of the material in the next four chapters (although you might
want to read this chapter to find out how to connect to the Net). On the other hand,
sharing your system's resources with others, whether in a local area network, a small
circle of friends, or the worldwide Internet community, can be most of the fun.</P>
<P>If you intend to use your Linux system to offer some of the Internet services
(such as FTP, WWW, or Gopher) but you don't want to let everyone gain access (maybe
just a few friends), you might not need to worry about connecting to the Internet.
You still have to set up the server software, though.
<H3 ALIGN="CENTER"><A NAME="Heading3<FONT COLOR="#000077">Connecting to the
Internet</FONT></H3>
<P>There are many different ways to connect to the Internet. Your choice of method
depends primarily on your usage habits and the services you want access to. It may
seem as though an overwhelming number of companies offer Internet access or services.
Luckily, there are really only four ways to connect to the Internet.</P>
<P>Briefly, these are your options for connecting to the Internet:
<UL>
<LI>A direct connection to the Internet--This method uses a dedicated machine (a
gateway) to connect into the Internet backbone. This method gives you full access
to all services but is expensive to set up and maintain.
<P>
<LI>Connecting through someone else's gateway--This usually involves getting permission
to use someone else's machine for full access to all Internet services.
<P>
<LI>Using a direct service provider--Uses a specialty company's gateway that your
machine can access to offer limited or full access to Internet services. These companies
are not the same as online services, because all they do is act as a gateway to the
Internet. Usually, this type of service provider uses modem or dedicated telephone
connections with high-speed lines to provide fast service.
<P>
<LI>Using an indirect service provider--Using an online company (such as Delphi or
CompuServe) to access some or all of the Internet's services. This is usually suitable
only for low-volume usage, and doesn't take advantage of Linux at all.
</UL>
<P>If you are part of a company or sharing the costs with a number of friends, online
service providers seldom are able to offer the level of performance you need for
support of e-mail, FTP, and other Internet services. As a further reason against
online services, most do not allow you to have your own domain name.</P>
<P>It is rare to find a gateway that you can "borrow" for access of your
own, unless you are willing to share the costs of the gateway. Most companies that
have a gateway will be reluctant to allow many outsiders to use their systems.</P>
<P>That leaves only a direct gateway of your own to the Internet or the use of a
service provider. The choice between these two options usually comes down to an issue
of the costs to connect both ways. Setting up your own gateway is expensive, but
may be cheaper than arranging accounts with a service provider if the volume of traffic
is high.</P>
<P>If you want access for yourself or for a very small company, it is unreasonable
to have your own dedicated gateway. Setting up an account with a service provider
is possible for individuals, but sometimes the costs and machine overhead are too
high. Service providers are typically used by small companies, but there is no reason
why you can't use a service provider if you anticipate a high Internet usage.
<H3 ALIGN="CENTER"><A NAME="Heading4<FONT COLOR="#000077">Services You Need</FONT></H3>
<P>When deciding which method you will use to access the Internet, one of the important
items to consider is the type of services you want from the Internet. If all you
need is e-mail, then any kind of access will provide it, but some may be ridiculously
expensive for what you get.</P>
<P>As a starting point, decide which of the following services are necessary and
which are less important:
<UL>
<LI>Electronic mail--Sending mail to and from other Internet users.
<P>
<LI>Telnet--Remote logins to other machines on the Internet.
<P>
<LI>FTP--File transfers between machines.
<P>
<LI>World Wide Web (WWW) access--A popular hypertext-based (and usually graphical)
information service.
<P>
<LI>Usenet newsgroups--A set of bulletin boards for conversations on many different
subjects.
<P>
<LI>Gopher--An information search and retrieval system.
<P>
<LI>WAIS--A menu-based document search and retrieval system.
<P>
<LI>Archie--A method for finding files to transfer.
<P>
<LI>Internet Relay Chat (IRC)--A conversation system much like CB radio.
</UL>
<P>Any system that is directly connected to the Internet through a gateway (yours,
a borrowed gateway, or most direct service providers) will provide complete access
to all the services listed. Some direct service providers support all the services,
but at a slower speed than a gateway. Slower speeds may be a limitation for the World
Wide Web if you intend to use and offer graphics (instead of just text). Some service
providers limit their access to e-mail and newsgroups, so a little research is necessary.
<H3 ALIGN="CENTER"><A NAME="Heading5<FONT COLOR="#000077">Direct Connection
Through a Gateway</FONT></H3>
<P>A direct connection (often called a dedicated connection) is one in which you
attach into the Internet backbone through a dedicated machine called a gateway or
IP router. The connection is over a dedicated telephone line capable of high-speed
transfers (usually at 1.44 megabits per second or faster). The gateway becomes part
of the Internet architecture and must remain online at all times. You can then use
any other computer on the gateway's network to access the Internet services.</P>
<P>Typically, dedicated connections mean high volumes of traffic and require systems
with an absolute minimum line speed of 9,600 baud, although high-speed fiber-optic
lines with speed capabilities of 45Mbps are not unusual. It is very unlikely an individual
or small company would have direct gateway access, primarily because of the high
cost of installation and maintenance requirements.</P>
<P>To create a direct access system, you must work with the Internet Network Information
Center (NIC) to set up the proper gateways on the Internet backbone for your domain.
The capital expense of such a system is high, both for the initial hardware and software
and for continuing support. High costs may also be involved with a dedicated telephone
line capable of supporting high-speed data transfer.
<H3 ALIGN="CENTER"><A NAME="Heading6<FONT COLOR="#000077">Connecting Through
Another Gateway</FONT></H3>
<P>An alternative method of connecting to the Internet through a gateway relies on
using a "friendly" machine or network. In such a system, a corporation
or educational institution that has an Internet gateway may allow you to access the
Internet through their system. Because this type of access gives you freedom on their
networks, many organizations now refuse this type of piggyback access.</P>
<P>If you are lucky enough to find a company or school that will let you use their
network, you simply call into a communications port on the network or gateway, then
route through the gateway to the Internet. In many ways, it is as though you are
a machine on the provider's network. Typically, you have unlimited access to the
Internet's services, although some companies do set restrictions.
<H3 ALIGN="CENTER"><A NAME="Heading7<FONT COLOR="#000077">Using a Service Provider</FONT></H3>
<P>Service providers are companies that have an Internet gateway that they share,
although the gateway is often transparent to the users. This type of connection is
often called "dialup" and uses SLIP (serial line interface protocol) or
PPP (point-to-point protocol). Some service providers offer UUCP connections for
e-mail.</P>
<P>Service providers usually charge a flat fee for membership, with an additional
charge based on the amount of time or the number of characters transferred. Joining
one of these services is quite easy. Domain names can be registered through many
service providers, too, allowing you to use your own domain even though you use a
provider.</P>
<P>The primary advantage of direct service providers is that effectively you are
directly connected to the Internet. All of the interworking with the service provider's
gateway is hidden inside your operating system's setup, making it transparent. A
disadvantage is that you cannot always arrange full access to the Internet. Some
services do not allow you to FTP through their gateway to another Internet site,
for example.</P>
<P>If you are considering using a direct service provider, you should ask the providers
in your area about the services they offer, whether special hardware or software
is needed, what the fees are, and whether they are based on a flat monthly rate or
based on usage, and the kind of technical support available in case you have trouble.</P>
<P>An alternative to using a commercial service provider is to rely on one of the
command-line access systems that are springing up in major cities. Such systems provide
Internet access through their own gateways as a free service (subsidized by a corporation
or government) or at a minimal cost. One popular access provider of this type is
FreeNet, an international organization that gives users a unique user name through
the FreeNet domain. FreeNet is currently only available in some cities, but it does
provide an extremely inexpensive and easy access method to the Internet. All you
need is an account (which is usually just a telephone call away), a modem, and communications
software.
<H3 ALIGN="CENTER"><A NAME="Heading8<FONT COLOR="#000077">Summary</FONT></H3>
<P>Choosing the method with which you connect to the Internet is up to you, but most
individuals find a direct service provider the best balance between cost and features,
as long as you plan to keep your system running most of the time. Once you have a
connection to the Internet, you can set up your server, as explained in the next
four chapters.
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