1. Chapter Three
3.2 The Internet
3.2.1 Overview of the Internet
3.2.1.1 Introduction to the
Internet
At the end of this topic, students
should be able to:
Explain about the Internet
2. What to cover?
• Definition of Internet
• Advantages and disadvantages of Internet
• Intranet & extranet
2
3. The Internet
• The Internet is a worldwide collection of networks that
links millions of businesses, government agencies,
educational institutions, and individuals
Discovering Computers : Chapter 2
3
Page 74
Figure 2-1
4. Evolution of the Internet
1969
ARPANET
becomes
functional
1984
ARPANET
has more
than 1,000
individual
computers
linked as
hosts
1986 NSF
connects
NSFnet to
ARPANET
and becomes
known as the
Internet
1995
NSFNet
terminates its
network on
the Internet
and resumes
status as
research
network
1996
Internet2 is
founded
Today More
than 550
million hosts
connect to
the Internet
Discovering Computers : Chapter 2
4
Pages 75 - 76
5. 5
• Vast amounts of data can be stored and processed
quickly and efficiently
• Information is available 24 hours a day through
access on the Internet or home computer files or
office/ workshop servers and computer facilities
Advantages of Internet
Accessibility
6. 6
• Decreases in storage costs and increases in
Internet connection speeds persuade more users
to use cloud storage for their data.
• Web application hosts often store users’ data and
information on their servers, which sometimes is
called cloud storage.
• Cloud storage also provides users with the
convenience of accessing their files from almost
anywhere.
Storage
Advantages of Internet
7. 7
• You don’t need to leave home to shop – you can
shop online and deal with bank transactions and
book holidays – an advantage if your are disabled
and cannot easily get out.
• You can work from home and use video
conferencing/ forum or chat to people across the
other side of the world. ( all of which saves money
and time)
Online activity
Advantages of Internet
8. 8
• Information is readily available, however
confidential information may be accessed unless
properly password controlled
• In many instances, where personal and
confidential records were not protected properly,
individuals have found their privacy violated and
identities stolen.
Disadvantages of Internet
Violation of Privacy
9. 9
• Adults, teens, and children around the world are
using Internet to share publicly their photos,
videos, journals, music, and other personal
information. Some of these unsuspecting,
innocent computer users have fallen victim to
crimes committed by dangerous strangers.
• Protect yourself and your dependents from these
criminals by being cautious in e-mail messages
and on Web sites.
Public Safety
Disadvantages of Internet
10. 10
• Prolonged or improper computer use to access to
the Internet can lead to injuries or disorders of
the hands, wrists, elbows, eyes, neck, and back.
• Computer users can protect themselves from
these health risks through proper workplace
design, good posture while at the computer, and
appropriately spaced work breaks.
• Two behavioral health risks are computer
addiction and technology overload
Health Risks
Disadvantages of Internet
11. Networks
An intranet is an
internal network
that uses Internet
technologies
An extranet allows
customers or
suppliers to access
part of its intranet
Discovering Computers : Chapter 9 11
Page 477
12. Intranet versus Extranet
Discovering Computers : Chapter 9 12
Page 477
Accessibility
Intranet Information accessible to employees
and facilitate collaboration within an
organization
Extranet Allow customers and suppliers to access
part of intranet
13. Chapter Three
3.2 The Internet
3.2.1 Overview of the Internet
3.2.1.2 The Internet Connection
At the end of this topic, students
should be able to:
Describe different types of Internet
connection
14. 1. Dial-up Connection
2. Broadband Internet Connection
14
Types of Connection and Internet Access
16. 1. Dial-up
o PC has to dial via a phone line to
connect
o Conventional dial-up
Slower, but cheaper
Ties up phone lines
Relatively secure from hackers
16
17. 2. ISDN
o Also transfer data over ordinary
telephone lines
o Typically uses two phone lines to
transfer data
o ISDN requires a special ISDN modem
Faster, but pricey
Doesn’t tie up phone line
Used by businesses and individuals
17
18. Advantages Disadvantages
• Security
• Include inexpensive
hardware
• Ease of setup and use
• Widespread availability
• Slow connection speed
(max of 56Kbps)
• Inconvenience
• Telephone line will be
tied up while accessing
the Internet
18
Advantages & disadvantages of
Dial-up Connection
19. • Also refer to Direct Connection or always-on
connections.
• Many home and small business users connect
to the Internet via high-speed broadband
Internet service
• PC is continually connected to the Internet
• Used in the home and office
• Because you are always connected, it is important
to protect your computer from hackers
19
2. Broadband Internet Connection
20. • Types of broadband connection
Discovering Computers : Chapter 2
20
Page 76
DSL
Fiber to
the
Premises
(FTTP)
Fixed
wireless
Cellular
Radio
Network
Cable
Internet
service
Wi-Fi
Satellite
Internet
Service
21. 21
• DSL – Digital Subscriber Line
• Broadband delivered over telephone lines
o Must be less than 3 miles from a switching station
o Transmits over telephone lines but does not tie up the
line
• Fast, direct Internet access via standard telephone
line
• ADSL (asymmetric digital subscriber line) is one of
the more popular types of DSLs.
DSL
22. How the Internet Operate
How might data travel the Internet using a
telephone line connection?
Step 1.
Request
data from
a server
on
Internet
Step 5. Regional
ISP uses leased
lines to send data
to a national ISP
Step 6.
National ISP
routes data
across the
country
Step 8. Server
sends data
back to you
Step 2. Modem
converts digital
signals to analog
signals
Step 3. Data
travels
through
telephone
lines to a
local ISP
Step 4. Data
passes
through
routers
Step 7.
National ISP
passes data to
local ISP
22
23. • Also known as Broadband over Fiber (BoF)
• Delivers over fiber-optic cabling all the way to the
building
o Available in limited areas
o Fast but expensive
• Uses fiber-optic cable
• Provide high-speed Internet access to house and
business users.
23
Fiber to the Premises (FTTP)
24. • Uses radio transmission towers rather than
satellites
• Not available in all areas.
• Expected to use Worldwide Interoperbility for
Microwave Access (WiMAX)
• Provides high-speed Internet connections using a
dish-shaped antenna to communicate via radio
signals.
24
Fixed wireless
25. • Also known as Mobile wireless
• Access via mobile phone or mobile device
• Offers high-speed Internet connections to devices
with built-in compatible technology or computers
with wireless modems.
• Categories : 1G, 2G, 3G, 4G, 5G.
25
Cellular Radio Network
26. • Cable: Most widely used home broadband
connection
• Provides high-speed Internet access through the
cable television network via a cable modem.
• A new technology in Malaysia
26
Cable Internet Service/ Cable Modem
28. • Data is transmitted through radio waves.
• Public wireless networks
o Both free and fee-based are available
o Currently Wi-Fi for short range, but WiMAX may
soon be an option
• Provide high-speed Internet connections to
compatible or properly equipped wireless
computers and device.
28
Wi-Fi (Wireless Fidelity)
29. • WiFi hotspots are places that provide a user
with free or paid Internet services. Eg: Airport,
Café, Hotel, hostel, Offices and other public
buildings.
Wi-Fi Hotspot
29
30. • Broadband option for rural areas
o Slower and more expensive than cable or DSL
o Available in many areas other broadband
options are not
• Provides high-speed Internet connections via
satellite.
• A satellite dish communicates with a satellite
modem.
30
Satellite Internet service
32. Difference between dial-up and
broadband
• Dial up connection speed is generally 56k
(sometimes slower). Basic entry level speed to
Broadband is 256k. The obvious difference here
is that the Broadband connection speed is almost
5 times faster than Dial up (Refer to ‘Broadband
Speeds’).
32
33. Chapter Three
3.2 The Internet
3.2.1 Overview of the Internet
3.2.1.3 Internet Service
Provider
At the end of this topic, students should
be able to:
1. Explain the Internet Service Provider.
2. List examples of Internet Service
Provider in Malaysia
34. • Access Providers is a business that provides individuals and
organizations access to the Internet for free or for a fee
• Access providers are categorized as
regional or national ISPs
online service providers
wireless Internet service providers
Access Providers
34
35. • An ISP (Internet service provider) is a regional or national
access provider.
ISP (Internet service provider)
35
Regional ISPs provide
Internet access to a
specific geographical
area
National ISPs provide
Internet access in cities
and towns nationwide
36. Responsibilities of an ISP
• Providing and maintaining a connection to the Internet
• Support the hardware and software needed to service that
connection
• To protect their site and network from external threats
such as viruses, hacker attacks and other illegal activities
• Provide 24-hour customer service and technical support
36
37. Examples of ISP in Malaysia
37
• TMNet
• TIME
• Maxis
• Celcom
• Jaring
• Digi
• Packet One Network
• Umobile
• YTL
38. Discovering Computers : Chapter 2
38
Page 78
• In addition to providing Internet access, an online service
provider (OSP) also has many members-only features such
as instant messaging or their own customized version of a
Web browser.
• A wireless Internet service provider, sometimes called a
wireless data provider, is a company that provides wireless
Internet access to desktop and notebook computers and
mobile devices, such as smart phones and portable media
players, with built-in wireless capability (such as Wi-Fi) or
to computers using wireless modems or wireless access
devices.
OSP & Wireless ISP
39. Online service
provider (OSP)
Has many members-only
features
Popular OSPs services
include
Wireless Internet
service provider
Provides wireless Internet
access to computers and
mobile devices
May require a wireless
modem
Discovering Computers : Chapter 2
39
Page 78
40. Chapter Three
3.2 The Internet
3.2.1 Overview of the Internet
3.2.1.4 The Internet Address
At the end of this topic, students should
be able to:
1. Identify the structure of IP address
2. Describe the purpose of an IP address
and its relationship to a domain name
41. Internet Address
The protocol that provides
for addressing and routing
Internet packets from one
computer to another
IP
(Internet Protocol)
41
A standard that outlines characteristics
of how two network devices
communicate is called a protocol.
• your computer must have an IP address (Internet Protocol address)
to connect to the Internet or another computer that has an IP
address.
• IP address has four parts number, separated by periods
• First portion of each IP address identifies the network
• Last portion identifies the specific computer
• The number in each group is between 0 and 255
42. A number that
uniquely identifies
each computer or
device connected
to the Internet
Definition of
IP address
A unique 32-bit
number assigned to
network devices
that use Internet
Protocol
42
**These all-numeric IP addresses are difficult to remember and
use. Thus, the Internet supports the use of a text name that
represents one or more IP addresses, known as Domain Name.
43. 0.0.0.0 (default network)
127.0.0.1 (for testing as a loopback
address)
255.255.255.255 (network broadcast) Special
reserved IP
addresses10.0.0.0 to 10.255.255.255
(private networks)
172.16.0.0 to 172.31.255.255
(private networks)
192.168.0.0 to 192.168.255.255
(private networks)
43
44. Domain name
• The text version of an IP address
• The text in the domain name up to the first period identifies the
type of Internet server.
• Every domain name contains a top-level domain (TLD), which is
the last section of the domain name. It is used usually to identify
the type of organization associated with the domain.
• You register for a domain name from a registrar, which is an
organization that sells and manages domain names.
Domain Name System (DNS)
• Method that the Internet uses to store domain names and their
corresponding IP addresses.
• translates the domain name into its associated IP address.
Domain Name System (DNS) Server
A server on the internet that usually is associated with an ISP.
44
46. Top-level
domain
(TLD)
The last
section of the
domain name
Example :
my – Malaysia
au – Australia
sg – Singapore
Purpose of
Top-level
domain
(TLD)
Country
Code Top-
level domain
(ccTLD)
46
Identifies the
type of
organization
associated
with the
domain
49. TLD for music and online
broadcasting
• .fm
• .ikim
• .astro
49
50. Version 4 of
Internet Protocol,
the most widely
used version of IP
Version 6 of
Internet Protocol,
has more capabilities
than IPv4, including
providing for far
more IP address
IPv4 IPv6
50
51. Currently, two versions of IP addresses exist: IPv4 (Internet
Protocol Version 4) and IPv6 (Internet Protocol Version 6).
An IPv4 address has two parts that identify a specific
computer: one part to identify the network where that computer
resides and a second part to pinpoint the specific computer or
host within that network.
Because each of the 8 bits can be 1 or 0, the total possible
combinations per octet are 28, or 256. Combining the four
octets of an IP address provides a possible 232 or 4,294,967,296
unique values.
51
52. 52
Billions of IP addresses sounds like a lot. But, because so
many computers and other devices connected to the
Internet need unique IP addresses, a growing shortage of IP
addresses exists.
An IPv6 address has three parts: a global prefix to identify
the network, a subnet to identify the location within the
network, and the interface ID to identify the specific
computer or host. IPv6 will use 216 (hexadecimal) is 128
bits address. Combining the eight octets of an IP address
provides a possible 2128 which will provide 3.4 x 1038, or
340,000,000,000,000,000,000,000,000,000,000,000,000 IP
addresses.
