Information Technology Reference
In-Depth Information
Registering a Domain Name
For any company wanting to do business on the Internet or just have an online presence, choosing the right domain
name is critical. Ideally, the domain name will match the company name as closely as possible. An exact match
may not be possible, however, because the name may already be taken. If your company needs a specific name
that is already taken, you may be able to buy the rights to that name from the current owner, or you may be able to
register the name with a different top-level domain. For example, instead of a .com address, you might be able to
get the .net or .biz version.
Anyone can register a domain name, as long as it doesn't belong to an existing company or organization. You can
register a domain name with a domain registrar company such as GoDaddy.com or 1&1.com. The exact cost var-
ies with the registrar, but is generally between US$10 and US$30 a year.
The name registration must be renewed on a yearly basis, but you can pay for multiple years at a time. When the
owner of a domain name fails to renew it, it becomes available for someone else to claim and register.
IP Addresses
Every computer that connects directly to the Internet has its own unique
numeric address, called its
IP address
. IP stands for Internet Protocol,
one of the protocols in the TCP/IP suite of protocols. A protocol is an
agreed-upon rule or standard; the Internet is based on TCP/IP rules.
Most networks today, including the Internet itself, use IP addressing to
identify computers. If you connect to the Internet through an Internet
service provider (ISP), your ISP assigns you an IP address automatically.
Depending on the ISP, that address may be a
static IP address
(that is,
permanently assigned to your modem) or a
dynamic IP address
(that is,
temporarily assigned to your modem as long as it is connected to the ISP).
IP address
A numeric address by which a par-
ticular computer is known on a network.
static IP address
An IP address that is perma-
nently assigned to a device.
dynamic IP address
An IP address that is
temporarily assigned to a device.
Running the
ipconfig
command at a command prompt displays your com-
puter's IP address, which is the private address assigned to it by your router.
To display a command prompt, click the Start button, type cmd, and press
Enter. Look for a line that includes “Local Area Connection.” You should see
the two addresses allocated to your computer—IPv6 first, followed by IPv4.
If you want to see your computer's public address—that is, the one it uses
on the Internet—visit
http://whatismyipaddress.com
. The main
page will display your computer's public IP address. There is also a map
that shows the geographical location of your Internet service provider.
How Domain Names and IP Addresses Are Related
If you enter an IP address in your web browser, the browser goes directly to
that site. If you enter a domain name, though, it goes to a
Domain Name
System (DNS)
server on the Internet, which is a directory lookup that
converts domain names into their corresponding IP addresses. Looking up
a name and finding the IP address is known as
name resolution
, or resolv-
ing the address. Your browser does this for you automatically.
Domain Name System (DNS)
The naming
system employed to enable users to access
websites using their domain names or URLs rather
than their IP addresses.
name resolution
The process of translating
domain names to numerical IP addresses. A DNS
server is used to resolve a name to an address.
Quick Review
1 What are the three main components of the Internet?
2 What are the three main components of a URL?
3 What are the two types of IP addresses?
4 What type of server is used to resolve (convert) domain names or URLs to IP addresses?
