Internet Address

The Internet Address

What is internet address?

o   also called an IP address (Internet Protocol address)

o   is a number that uniquely identifies each

                 computer or device connected to the Internet

o   Contains four (4) part of numbers.

o   The number in each group is between 0 and 255

Domain name

•The text version of an IP address

Generally,

•First portion of each IP address identifies the network

•Last portion identifies the specific computer

 Special reserved addresses

Examples of TLD

Internet Service Provider

Internet Service Provider

Access Providers 

An access provider is a business that provides 

individuals and organizations access 

to the Internet free or for a fee.

–Internet Service Provider

–Online Service Provider

–Wireless Internet Service Provider

Regional or national Internet access provider.

Regional ISPs → provide Internet access to a specific geographical area

National ISPs → provide Internet access in

cities and towns nationwide

Responsibilities of an ISP

•Providing and maintaining a connection to the Internet

•Support the hardware and software needed.

•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

Examples of ISP in Malaysia

Network Basic

How Are LAN, MAN, and WAN Different? 

Local Area Network (LAN):

 Definition

•A local area network (LAN) is a network that 

connects computers and devices 

in a limited geographical area.

•The simplest form of LAN is to 

connect two computers together.

Advantages 

•Easy to share devices           (printers, scanners,                                                           external drives)

•Easy to share data                          (homework,                                                                         pictures)

Disadvantages 

•Area covered is limited to a few kilometres.

•Speed access is slow if many computers 

running at the same time.

Metropolitan Area Network (MAN):

Definition

•A metropolitan area network (MAN) is a high-speed 

network that connects local area networks in a 

metropolitan area such as a city or town and handles the 

bulk of communications activity across that area.

Advantages

•efficiency and shared access data.

•All the computer-owning residents 

of the area have equal 

ability to go on line. 

Disadvantages

•It can be costly               (hardware, software,                                 support, etc.).

•As the network consists of many computers over a city, the connection can become quite slow.

Wide Area Network (WAN):

Definition

 •A wide area network (WAN) is a network that covers a 

large geographic area (such as a city, country, or the world) 

using a communications channel that combines many types 

of media such as telephone lines, cables, and radio waves.

•The Internet is the largest WAN in the world.

Advantages

•increased efficiency.

•ease of communication. 

Disadvantages

•High security problems

•Maintenance problems. Large enterprises 

will dedicate personnel to maintaining 

their WAN.

Network

What is Network ?

Network is a collection of computers and

devices connected together via

communication devices and

transmission media.

What is Network Topology ?

A network topology refers to the layout of

the computers and devices in a 

communications network.

It refers to both the physical and logical

layout of a network.

Physical Topology Layout

 The arrangement of a cabling is the physical

   topology.

Logical Topology Layout

 The path that data travels between computers

  on a network.

Types of network topology.

THREE commonly used network topologies are:

   Star network      ⟶      

                                 

   Bus network       ⟶              

   Ring network       ⟶       

(1) Star Network Topology

 All the computers and other 

devices on the network

 connect to a central 

device, to form a star.

Two (2) types of devices that provide a common

  central connection point to all the other devices

  on the network are a hub and a switch.

*The device that provides a common central 

connection point for other devices on a 

  network.

 *All data that transfers from one device to 

  another device passes through the hub or 

  switch.

 *The hub takes a signal that comes from 

any device and passes it along to all

  the other devices in the network

Advantages:

1. If one device fails, ONLY that device is affected.

Disadvantages:

1. If the hub or switch FAILS, the entire network will

    be inoperable until the device is repaired.

(2) Bus Network Topology

   A bus network consists of a single central

    cable (backbone), 

to which all computers and

    other devices connect.

The bus is the physical cable that connects the

  computers and other devices.

 The bus in a bus network transmit data,

  instructions, and information  as a series of signal.

 Those signals are sent as electrical pulses that

  travel along the length of the cable in all directions.

Each devices is connected to the single bus

  cable through T-Connector.

 A terminator  is required at each end of the bus cable to prevent the signal from bouncing back and forth on the bus cable.
               

Advantages:

1. Bus networks are not expensive and easy to

    install.

Disadvantages:

1. There might be disruption when the cable (backbone)

     is break. It is because all systems on the network

     connect to a single cable or backbone.

(3) Ring Network Topology

 On a ring network, 

a cable forms 

a closed loop(ring) 

with all computers 

and devices arranged

  along the ring.

Data transmitted on a ring network travels from

  device to device around the entire ring, in one

  direction (clockwise or counterclockwise)

 Token passing is one method for sending data

   around a ring.  A token, which is a special

   bit pattern, travels around the circle.

 Each device takes a turn sending and receiving

  information through the use of a token.

Advantages:

1. The transmission of data is relatively

    simple as packets (A piece of a message

    transmitted) travel in one direction only.

Disadvantages:

1. A failure in any cable or device breaks the

    loop and can take down the entire network.