2. INTRODUCTION
• A computer network is a set of computers connected together for the purpose of sharing
resources. The most common resource shared today is connection to the Internet. Other
shared resources can include a printer or a file server. The Internet itself can be considered a
computer network.
• Computer networks support an enormous number of applications and services such as access
to the World Wide Web, digital video, digital audio, shared use of application and storage
servers, printers, and fax machines, and use of email and instant messaging applications as
well as many others. Computer networks differ in the transmission medium used to carry
their signals, communications protocols to organize network traffic, the network's
size, topology, traffic control mechanism and organizational intent. The best-known computer
network is the Internet.
3.
4. LOCAL AREA NETWORK (LAN)
• A local-area network (LAN) is a computer network that spans a relatively small area. Most
often, a LAN is confined to a single room, building or group of buildings, however, one LAN
can be connected to other LANs over any distance via telephone lines and radio waves.
• A system of LANs connected in this way is called a wide-area network (WAN). The difference
between a LAN and WAN is that the wide-area network spans a relatively large geographical
area. Typically, a WAN consists of two or more local-area networks (LANs) and are often
connected through public networks.
5. TYPES OF LOCAL-AREA
NETWORKS (LANS)
There are many different types of LANs,
with Ethernets being the most common for
PCs. Most Apple Macintosh networks are based
on Apple's AppleTalk network system, which is
built into Macintosh computers. The following
characteristics differentiate one LAN from
another:
Topology: The geometric arrangement of
devices on the network. For example, devices
can be arranged in a ring or in a straight line.
Protocols: The rules and encoding
specifications for sending data. The protocols
also determine whether the network uses a
peer-to-peer or client/server architecture.
Media: Devices can be connected by twisted-
pair wire, coaxial cables, or fiber optic cables.
Some networks do without connecting media
altogether, communicating instead via radio
waves
6.
7. WIDE AREA NETWORK (WAN)
• A wide area network (WAN) is a network that exists over a large-scale geographical area. A
WAN connects different smaller networks, including local area networks (LANs) and metro
area networks (MANs). This ensures that computers and users in one location can
communicate with computers and users in other locations. WAN implementation can be
done either with the help of the public transmission system or a private network.
• A WAN connects more than one LAN and is used for larger geographical areas. WANs are
similar to a banking system, where hundreds of branches in different cities are connected
with each other in order to share their official data.
• A WAN works in a similar fashion to a LAN, just on a larger scale. Typically, TCP/IP is the
protocol used for a WAN in combination with devices such as routers, switches, firewalls and
modems.
8. TYPES OF WIDE-AREA
NETWORKS
A WAN (Wide Area Network) network can be established
in many ways and different types of WAN. Wan can be
established using leased lines, circuit switch network,
packet switching, frame or packet relay and cell relays.
Packet switching is the one of the most common types of
establishing a WAN (Wide Area Network) network. In a
packet switching method a digital network is established.
In this method suitable data blocks are created. These
data blocks are known as packets. The data travels in the
form of varied bit rate. These bits travel in the form of
sequences of packets over the network and their delay is
dependent upon the load of traffic over the network.X.25
and frame relays are the most suitable protocols for this
kind of network. Leased lines are the other most suitable
and quick way to establish a WAN (Wide Area Network).
9.
10. METROPOLITAN AREA NETWORK (MAN)
• A metropolitan area network (MAN) is a [computer network] that interconnects users with
computer resources in a geographic area or region larger than that covered by even a large
local area network (LAN) but smaller than the area covered by a wide area network (WAN).
• A MAN is ideal for many kinds of network users because it is a medium-size network. MANs
are used to build networks with high data connection speeds for cities and towns.
• MANs are extremely efficient and provide fast communication via high-speed carriers, such
as fiber optic cables
11. TYPES OF METROPOLITAN
-AREA NETWORKS
Most widely used technologies to develop a MAN
(Metropolitan Area Network) network are FDDI (fiber
distribution data interface), ATM (Asynchronous Transfer
Mode) and SMDS (switched multi megabit data
service).ATM (Asynchronous Transfer Mode) is the most
frequently used of all. ATM (Asynchronous Transfer Mode)
is a digital data transfer technology. It was developed in
1980 to improve the transportation of real time data over
a single network. ATM (Asynchronous Transfer Mode)
works just like cell relay system, where data is separated
in the form of fixed equal sized packets and is transferred
overtime. The purpose of ATM (Asynchronous Transfer
Mode) was to access clear audio and video results during
a video conferencing. The attributes of ATM has enabled it
to become a base of wide area data networking.
12.
13. BASIS OF
COMPARISON
LAN WAN MAN
Expands to Local Area Network Wide Area Network Metropolitan Area
Network
Meaning A network that
connects a group of
computers in a small
geographical area.
It spans large locality
and connects
countries together.
Example Internet.
It covers relatively
large region such as
cities, towns.
Ownership of
Network
Private Private or Public Private or Public
Design and
maintenance
Easy Difficult Difficult
Speed High Low Moderate
Used for
College, School,
Hospital
Country/Continent. Small towns, City.
DIFFRENCE BETWEEN LAN ,WAN,MAN