This document defines and describes different types of computer networks. It explains that a computer network connects computers together to share resources. There are three main types of networks based on size: local area networks (LANs) which connect computers within a single site or building; metropolitan area networks (MANs) which connect LANs over a larger geographic area like a city; and wide area networks (WANs) which interconnect LANs across geographic distances that could span multiple cities or countries. The key differences between these network types are their size, connection technology, and purpose.

1. By: Sudakshi Samarawickrama

2.  A computer network is a set of computers connected together
for the purpose of sharing resources.
 Computers on a network are called nodes.
 The connection between computers can be done,
# via cabling
# wirelessly through radio waves
 Connected computers can share resources, like access to the
Internet, printers, file servers, and others.
 A network is a multipurpose connection, which allows a single
computer to do more.

3.  Computer network can be characterized by their
geographical area they occupy as well as their purpose.
 Network can cover anything from a handful of devices
within a single room to millions of devices spread
across the entire globe.
 Network fall into 3 classes based on the size are,
1. LAN - Local Area Network
2. MAN - Metropolitan Area Network
3. WAN - Wide Area Network

4.  Consists of a computer network at a single site,
typically an individual office building.
 A LAN is very useful for sharing resources, such as
data storage and printers.
 The various devices on the LAN are connected to
central devices called Hub or Switch using cables.

6.  Ethernet ,
# Network protocol that controls how data
transmitted over a LAN.
# Technically it is referred as the IEE
802.3
 WLAN – Wireless Local Area Network
# It is standarized by IEE 802.11.
# It shares many properties with wired
ethernet.

7. ADVANTAGES
 Resource Sharing
 Software Applications
Sharing
 Easy and Cheap
Communication
 Centralized Data
 Data Security
 Internet Sharing
DISADVANTAGES
 High setup cost.
 Privacy Violations
 Data Security Threat
 LAN Maintenance Job
 Covers Limited Area

8.  Computer network that interconnects users
with computer resources in a geographic area
or region larger than that covered by even a
large LAN.
 Depending on the configuration, this type of
network can cover an area from several miles
to tens of miles.
 A MAN is often used to connect several LANs
together to form a bigger network.

10. ADVANTAGES
 Bandwith of connecting links.
 Increases the efficiency of handling
data.
 Increase the speed of transferring data.
 Cost effective by Sharing of resources
such as printers.
 Offers centralized management of data.
 Enables people to connect many fast
LANs together.
 Flexibility of the proposed services.
 High security.
DISADVANTAGES
 The large the network becomes
difficult to mange.
 Difficult to make the system
secure from hackers.
 More cables required for MAN
connection from one place to
other.

11.  Network of networks.
 Geographically distributed private
telecommunication network that interconnect
multiple LAN networks.
 WAN are characterized by the slowest data
communication rates and largest distance.

13. # enterprise WAN,
corporate network that connects
geographically dispersed users areas that
could be anywhere in the world.
# global WAN ,
any network that is composed of
different interconnected computer networks
(WANs) and also covers an unlimited
geographical area.

14. ADVANTAGES
 Covers a large geographical
area.
 Allows connecting
workstations to share
resources and software.
 For network database,WAN
allows users all over a network
to access and update a single
consistent view of data.
DISADVANTAGES
 High costs.
 More associated errors
 Require to invest in a good
firewall system to avoid
disruption by hackers.
 Once set up, maintaining a
network is a full-time job which
requires network supervisors
and technicians to be employed.
 Low security (Vulnerable to
hackers or other outside threats)

15. END