This document defines and describes common computer networking components. It explains that a local area network (LAN) connects computers in a limited area like a home or office, while a wide area network (WAN) spans a larger geographic area like the Internet. It also defines networking devices like hubs, switches, bridges, routers, gateways, modems, network interfaces, and firewalls; and describes their basic functions in joining or connecting different parts of a computer network.

1. Module 3: INSTALL COMPUTER SYSTEMS AND NETWORKS
Lesson 1: PLAN AND PREPARE FOR INSTALLATION
1.4 NETWORK
COMPUTER HARDWARE SERVICING
INFORMATION & COMMUNICATIONS TECHNOLOGY
NUEVA ECIJA HIGH SCHOOL

2. What is a local area
network (LAN)?
 Network in limited
geographical area
such as home or
office building

3. What is a wide area
network (WAN)?
 Network that covers
large geographic
area using many
types of media
 Internet is world’s
largest WAN

4. Hub is a small, simple,
inexpensive device that
joins multiple computers
together. Many network
hubs available today
support the Ethernet
standard. Other types
including USB hubs also
exist, but Ethernet is the
type traditionally used in
home networking.

5. Ethernet switch is a
device that gathers the
signals from devices that
are connected to it, and
then regenerates a new
copy of each signal.

6. Bridge is a device filters
data traffic at a network
boundary. Bridges reduce
the amount of traffic on
a LAN by dividing it into
two segments.

7. Routers are small
physical devices that join
multiple networks
together.

8. Network gateway is an
internetworking system
capable of joining
together two networks
that use different base
protocols. A network
gateway can be
implemented completely
in software, completely
in hardware, or as a
combination of both.

9. Modem is a contraction of
the terms modulator and
demodulator. Modems
perform a simple function:
They translate digital
signals from a computer
into analog signals that can
travel across conventional
phone lines. The modem
modulates the signal at the
sending end and
demodulates at the
receiving end.

10. Network interface is a
device that connects a client
computer, server, printer or
other component to your
network. Most often, a
network interface consists
of a small electronic circuit
board that is inserted into a
slot inside a computer or
printer. Alternatively, some
computers, printers, or
other services include
network interfaces as part
of their main circuit boards
(motherboards).

11. Network firewall protects a
computer network from
unauthorized access.
Network firewalls may be
hardware devices, software
programs, or a combination
of the two. Network firewalls
guard an internal computer
network (home, school,
business intranet) against
malicious access from the
outside. Network firewalls
may also be configured to
limit access to the outside
from internal users.

12. Module 3: INSTALL COMPUTER SYSTEMS AND NETWORKS
Lesson 1: PLAN AND PREPARE FOR INSTALLATION
1.4 NETWORK
COMPUTER HARDWARE SERVICING
INFORMATION & COMMUNICATIONS TECHNOLOGY
NUEVA ECIJA HIGH SCHOOL