A network connects computers and devices to allow sharing of resources and communication. There are three main types of networks: local area networks (LANs) which connect devices within a small area like a home or building; metropolitan area networks (MANs) which connect a city; and wide area networks (WANs) which connect large geographic areas using various media types. LANs allow resource sharing and high-speed communication within an organization, but require memory and add complexity, while MANs and WANs connect larger areas but use different technologies like fiber cables or satellites.

2. Topics
 What is network ?
 Types of networks
• LAN (Local Area Network)
• MAN (Metropolitan Area Network)
• WAN (Wide Area Network)
 Comparison between the three
networks.

3. NETWORKS
What is a network?
 Collection of
computers and
devices connected
via communications
devices and
transmission
media
 Networks can be
classified by the
geographical area
they cover

4. There are 3 types of computer networks
 LAN (Local Area Networks)
 MAN (Metropolitan Area Network)
 WAN(Wide Area Network)

5. TYPES OF NETWORKS
What is a local area
network (LAN)?
 Network in limited
geographical area
such as home or office
building
 LAN covers a small
region of space
typically a single
building, schools or at
home

6.  LAN can pass data to one and all as well as can
share resources.
 Once PC’s are physically connected, software
designed specifically for LAN allows the exchange of
program and data files among users connected to the
network.
 The network software allows any user to access
shared data storage(hardware) and output devices
(printers) connected to networks.
 A group of computers and other devices dispersed
over a relatively limited area say within a building and
connected by a communication link that enables each
device to interact with any other device on the network
is called LAN.

7. Advantages of LAN
 LAN allow sharing of expensive resources such as
laser printers and high-capacity , high speed mass
storage devices among a number of users.
 LAN allows high speed exchange of essential
information between key people in an organization.
If properly managed, this will provide greater
efficiency and productivity.
 Through LAN, one can store all critical data at a
central place and many users can then access and
work on this data.
 Since data can be stored centrally, you can take the
back-up of all important files daily on tapes or hard
disk drives,

8. Disadvantages of LAN
 LAN software requires memory space in each of
the computers used on the network. About 20% of
the computer’s memory will be needed to manage
the network interface. This reduces the memory
space available for user’s programs.
 LAN adds another level of complexity to the
computer operation. Users may have difficulty in
learning the network commands.
 Some control on the part of a user is lost. For
example , suppose you have to share a printer with
other users, then you can face a situation where the
entire network suddenly locking up because one
user has made a mistake.

9. Disadvantages of LAN
 LAN has security problems. Some types of security
system must be implemented for protecting data.
Any user can play foul and destroy the centrally
stored data easily on a network.

10. Example on LAN:
Two or more computers connected in a
building or small office or a internet café.

11. TYPES OF NETWORKS
Metropolitan area network(MAN)
•MAN is a data network intended to
serve an area approximately that of
a large city.
•Such networks are being
implemented by techniques like
running fibre cables through
subway tunnels and satellites.
•Popular example of MAN is
SDBS(Switched Multimegabit Data
Service).

13. Example of MAN:
 Popular example of MAN is
SDBS(Switched Multimegabit Data
Service).
 SDBS is a high-speed, packet-switched,
datagram-based WAN networking
technology used for communication over
public data networks(PDNs). SMDS can use
fiber- or copper-based media; it supports
speeds of 1.544 Mbps.

14. TYPES OF NETWORKS
What is a wide area
network (WAN)?
 Network that covers large
geographic area using
many types of media
 Internet is world’s largest
WAN
 Can be a collection of
LANs or WANs or the mix of two
with a very large geographical
area for instant a country or
even beyond the border
 Dedicated transoceanic
cabling or satellite uplinks may
be used to connect this type of
network.

15. Wide Area Network (WAN)

16. Comparison between the three types of computer
networks

17. Any Queries ?