1. Topic 3
INTERNET TECHNOLOGY
3.2 The Internet
3.2.1 Overview of the Internet
3.2.1.4 The Internet Address
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2. Learning Outcome
At the end of this topic, students should be able to:
• Identify the structure of IP Address.
• Describe the purpose of an IP Address and its
relationship to a domain name.
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3. Internet Address
 What is an IP Address?
• An IP address (Internet Protocol address) is a number
that uniquely identifies each computer or device
connected to the Internet.
 Why does an IP Address exist?
• It exists as the Internet relies on an addressing system
much like the postal service to send data and
information to a computer at a specific destination.
Note: No two machine have the same IP address.
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4. Internet Address
 What does an IP Address consist of?
• The IP address consists of four groups of numbers,
each separated by a period that uniquely identifies
(address of network and specific device). The number
in each group is between 0 and 255.
• In other words, IP address are 32-bit numbers,
written in dotted decimal notation. Each 4 bytes is
written in decimal format between 0 to 255.
The lowest IP address : 0.0.0.0
The highest IP address : 255.255.255.255
Examples of IP address : 72.14.207.99
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5. Internet Address
 How does an IP Address look like?
• A typical IP address looks like this:
216.27.61.137
• To make it easier for us humans to remember, IP
address is expressed in decimal format as a "dotted
decimal number" like the one above.
• In general, the first portion of each IP address
identifies the network and the last portion identifies
the specific computer.
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6. Internet Address
• But remember, computers communicate in binary
form. Look at the same IP address in binary:
11011000.00011011.00111101.10001001
• If you add all the positions together, you get 32,
which is why IP address is considered 32-bit numbers.
• Since IP address is difficult to remember and use.
Thus, the Internet supports the use of a text name
that represents one or more IP addresses.
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7. Example IP Adress
0.0.0.0 (default network)
127.0.0.1 (for testing as a loopback address)
255.255.255.255 (network broadcast)
Special
reserved
10.0.0.0 to 10.255.255.255 addresses
(private networks)
172.16.0.0 to 172.31.255.255
(private networks)
192.168.0.0 to 192.168.255.255
(private networks)

8. Domain Name
 What is a Domain Name?
• A domain name is the text version of an IP address.
• As with an IP address, the components of a domain
name are separated by periods.
IP address 72.14.207.99
Domain name www.google.com
top-level domain
The IP address and domain name for the Google Web site
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9. Domain Name
• Every domain name contains a top-level domain
(TLD), which is the last section of the domain name.
• A generic TLD (gTLD), identifies the type of
organization associated with the domain.
• In the domain name www.google.com, the top-level
domain is .com
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10. Domain Name
A generic top-level domain (gTLD) is one of the categories of top-
level domains (TLDs) maintained by the Internet Assigned
Numbers Authority (IANA) for use in the Domain Name
System(DNS) of the Internet.
generic Domain
Top-level Top-level name
domain domain system
(TLD) (gTLD) (DNS)
The last section of Identifies the type translates the
the domain name of organization domain name into
associated with its associated IP
the domain address.

11. Domain Name
• The organization that assigns and controls top-level
domains is the Internet Corporation for Assigned
Names and Numbers (ICANN pronounced EYE-can).
• The domain name system (DNS) is the method that
the Internet uses to store domain names and their
corresponding IP addresses.
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12. Domain Name
• When you specify a domain name, a DNS server
translates the domain name to its associated IP
address so that data and information can be routed to
the correct computer.
• A DNS server is an Internet server that usually is
associated with an Internet service provider.
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13. Domain Name Examples
Examples of Generic Top-Level Domains
Generic TLD Intended Purpose
aero Aviation community members
biz Businesses of all sizes
cat Catalan cultural community
com Commercial organizations, businesses, and companies
coop Business cooperatives such as credit unions and rural electric co-ops
edu Educational institutions
gov Government agencies
info Business organizations or individuals providing general information
jobs Employment or human resource businesses
mil Military organizations
mobi Delivery and management of mobile Internet services
museum Accredited museums
name Individuals or families
net Network providers or commercial companies
org Nonprofit organizations
pro Certified professionals such as doctors, lawyers, and accountants
tel Internet communications
travel Travel industry 13

14. Internet Address Protocol
The protocol of the Internet is called TCP/IP
(Transmission Control Protocol/Internet Protocol) .
TCP/IP – allowing cross-network communication for
almost every type of computer and network.
The protocol that provides
for addressing and routing IP
Internet packets from one (Internet Protocol)
computer to another

15. Internet Address Protocol
TCP protocol – defines a system similar in many
ways to the postal system. A message that sent on
the Internet is broken into packets. Each packet has
all the information routers need to transfer the
packet from network to network towards it
destination.
IP – defines the addressing system of the Internet.
Every host computer on the Internet has a unique
IP address

16. IPv4 IPv6
Version 6 of
Version 4 of Internet Protocol,
Internet Protocol, has more capabilities
the most widely than IPv4, including
used version of IP providing for far
more IP address