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Transcript
“Getting
to Know Networks”
What Is a Network?
A network is a collection of computers hooked up together,
usually by cables or telephone wires, for the purpose of sharing
information and resources.
Commonly connected devices include personal computers
(PCs), minicomputers, mainframe computers, terminals,
workstations, printers, fax machines, smartphones, and various
data-storage devices.
Advantages of Networks
The most obvious benefit is that you can store virtually any
kind of information at a central location on the network as well
as access it from any connected computer. Other advantages
are:
1. Cost-effective Resource Sharing—peripherals can be shared.
2. Streamlined Business Processes—tasks such as employee
collaboration on projects and holding meetings can take less
time and cost less.
3. Cheaper Sales Process—networks connect businesses to
customers through the electronic storefront: a Web site allows
customers to search for and order products and services.
Advantages
4. Secure Management of Sensitive Information—
the ability to protect network resources and files.
Proper security features will control who will have
access to sensitive data, equipment, and other
resources.
5. Worldwide, Instantaneous Access to
Information—you will be able to distribute
critical information to many locations anywhere in
the world, almost instantaneously.
Recent Networked Peripherals
Recently, other types of devices have become
network-connectable, including interactive
televisions, smartphones, tablets, ebooks, GPS, and
environmental control systems.
Networked devices everywhere provide two-way
access to a vast array of resources on a global
computer network through the largest network of
all—the Internet.
Types of Network Stations
LAN—Local area networks operate primarily over a
small area, such as an office building. The cables that
hook parts of the network up together are owned by the
user.
WAN—Wide area networks covers a large area, such
as all the branches of a bank. It is usually connected
through leased telephone lines and satellite hookups.
Hardware Needed
1. Network Interface Cards—an expansion board
inserted into a computer so the computer can be
connected to a network.
2. Networking Software—directs the communication
functions, security protection, and data and
peripheral sharing within a group of computers.
Examples include Novell and Windows NT.
3. Networking Security—The authorization of access
to data in a network.
How Does Fiber Optics Work?
Instead of sending electrical signals through metal, light
pulses are transmitted. While plastic cables are easier to
install, glass allows you to transmit network signals over
a much longer distance. Fiber optics is faster than
standard electronics because transmission travels at the
speed of light.
What’s Network Physical Topology?
 “Network topology” refers to the layout of a network. Due to
the specific nature of computer network technology,
networks must be arranged in a particular way in order to
work properly. Some of them include:
– Ring
– Bus
– Star
– Tree
What Is a Ring Topology?
The most common topology today is a collapsed ring. This is due to the
success of a network protocol called the Ethernet. This protocol, or a
network language, supports the Internet, Local Area Networks, and Wide
Area Networks.


In this design, computers are connected via a single cable, but the
end nodes also are connected to each other. In this design, the
signal circulates through the network until it finds the intended
recipient. If a network node is not configured properly, or it is down
temporarily for another reason, the signal will make a number of
attempts to find its destination.
A collapsed ring is a topology where the central node is a network
device called a hub, a router, or a switch. This device runs a ring
topology internally and features plugins for cables. Next, each
computer has an independent cable, which plugs into the device.
Most modern offices have a cabling closet, or a space containing a
switch device that connects the network. All computers in the office
connect to the cabling closet and the switch. Even if a network plug
is near a desk, the plug is connected via a cable to the cabling
closet.
What Is a Bus Topology?
A bus topology is another type of design
where a single cable connects all
computers and the information intended
for the last node on the network must
run through each connected computer.
If a cable is broken, all computers
connected down the line cannot reach
the network.
The benefit of a bus topology is a
minimal use of cabling.
What Is Star Topology?
A star topology is a design of a network where
a central node extends a cable to each computer
on the network. On a star network, computers
are connected independently to the center of the
network.
If a cable is broken, the other computers can
operate without problems.
A star topology requires a lot of cabling
LAN Office Layout
Star Topology
secure room
network server
printer
Hub
scanner
twisted-pair cable
network
administrator
USB cable
workstation
digital camera
Smart phones
The Future of Wireless Technology?
Wireless topologies differ greatly from wired topologies,
because the medium (radio frequencies) has different properties
than wires. The principles used in creating wireless networking
solutions are based on the technology currently in use with
cellular telephone systems.
So far, there have been three generations of mobile
technologies. The first generation is the analog cellular system,
the second is digital wireless, and the third generation (3G).
This system is designed to be an always-on service for
everything from voice to video to data transfer.
Thank you for viewing
“Getting to Know Networks”!