TOPOLOGY
Network topology
is the arrangement of various elements as links, nodes etc. It refers to the way
in which network of computers is connected.
Choice of topology is dependent upon:-
·
type
and number of devices used
·
rate
of data transfer
·
cost
Types:-
Physical
Topology- Physical location
of devices and cable installation in a network. It defies how devices are
connected in a network through cables. It is a physical structure of a network.
Logical
Topology- It shows the flow of data within a network. - It also referred as Signal
topology. It is used to describe the arrangement of devices in a network and
how they communicate with each other.
Network Topologies:
·
Bus- Bus topology is used in LAN where each
computer is connected to a single cable i.e. Backbone cable. As there is a use
of only one single cable and that can be single
point of failure.
·
Ring- Ring topology
is designed in a circular form in which data travels through ring in one
direction. When device sends data, it travels through each device until each
reaches its destination.
·
Star- In this
topology, each computer is connected to a central device that can be switch/hub.
Central device is the server and nodes/computers are clients. It is easy to
design and implement. Central device can be a single point of failure.
·
Tree- It is based
on hierarchy of computer systems. The highest level of tree network consist a
single root computer and this will further connected to lower level
computers.
It can be a combination
of Bus and star topology.
·
Mesh- In this
topology, all computers are directly connected to each other. There is no
need to use switching nor broadcasting. This topology is more
costly than other topologies as there is a use of more cables. It is not used
for connecting computer networks basically used to connect routers.
LAN
Transmission Methods:-
·
Unicast
·
Multicast
·
Broadcast