What is Topology?
o Network topologies describe the methods in which all the elements of a network are mapped. The
topology term refers to both the physical and logical layout of a network.
o Network topologies refer to the arrangement and connection patterns of computers in the network.
o It is the physical layout of the terminals, links, and computers in the network.
o Network topology can be defined as the cabling structure or geographical arrangement of computers
in the network.
o Network topology can be defined as the cabling structure of the geographical arrangement of
computers in a Local Area is known as Network Topology or LAN Topology.
Network topologies are of several types. Some topologies used in LAN are as follows:
o Bus or Linear topology
o Star Topology
o Ring Topology
o Tree Topology
o Mesh Topology
Bus or linear topology
o In this type of topology, all the nodes (computers as well as servers) are connected to a single cable
with the help of interface connectors.
o This central cable is called the backbone of the network and is known as Bus.
o Every workstation communicates with the other devices through this Bus.
o It’s every end has a terminator and the terminator stops the flow of data out of the bus.
o In this network, if the cable breaks, it affects the whole network.
o There is a maximum chance of collision of data.
Advantages of Bus Topology
It is easy to set up and extend.
Bus topology is comparatively cheaper.
The cable length is required for this topology is the least compared to other networks.
Linear Bus network is mostly used in small networks.
Disadvantages of Bus Topology
If the main cable (i.e. bus) encounters any problem, the whole network breaks down.
There is a maximum chance of collision of data.
It is difficult to detect and troubleshoot fault at the individual stations.
CN- UNIT V Page 1
,Ring Topology
o In a ring network, every device has exactly two neighboring devices for communication purpose.
o It is called a ring topology as its formation is like a ring. In this topology, every computer is
connected to another computer.
o Here, the last node is combined with a first one.
o This topology uses token to pass the information from one computer to another. In this topology, all
the messages travel through a ring in the same direction.
Advantages:
Easy to install and reconfigure.
Adding or deleting a device in-ring topology needs you to move only two connections.
The troubleshooting process is difficult in a ring topology.
Failure of one computer can disturb the whole network.
Offers equal access to all the computers of the networks
Faster error checking and acknowledgment.
Disadvantages:
Unidirectional traffic.
Break in a single ring can risk the breaking of the entire network
Modern days high-speed LANs made this topology less popular.
In the ring, topology signals are circulating at all times, which develops unwanted power
consumption.
It is very difficult to troubleshoot the ring network.
Adding or removing the computers can disturb the network activity.
Star Topology
o This is the most commonly used and popular topologies in LAN.
o In this topology, all the components of the network are connected to the central device (which may
be a hub, a router, or a switch).
o This hub is the central node and all other nodes are connected to the central node.
o In the star topology, all the computers connect with the help of a hub.
o This cable is called a central node, and all other nodes are connected using this central node.
o It is most popular on LAN networks as they are inexpensive and easy to install.
CN- UNIT V Page 2
, Advantages:
Easy to troubleshoot, set up, and modify.
Only those nodes are affected, that has failed. Other nodes still work.
Fast performance with few nodes and very low network traffic.
In Star topology, addition, deletion, and moving of the devices are easy.
Disadvantages:
If the hub or concentrator fails, attached nodes are disabled.
Cost of installation of star topology is costly.
Heavy network traffic can sometimes slow the bus considerably.
Performance depends on the hub’s capacity
A damaged cable or lack of proper termination may bring the network down.
Mesh Topology
o The mesh topology has a unique network design in which each computer on the network connects to
every other
o It is develops a P2P (point-to-point) connection between all the devices of the network.
o It offers a high level of redundancy, so even if one network cable fails, still data has an alternative
path to reach its destination.
o Mesh topologies involve the concept of routes.
o In a mesh network, every device connects to every other by a communication cable. The control is
distributed with each node deciding its communication priorities.
CN- UNIT V Page 3
o Network topologies describe the methods in which all the elements of a network are mapped. The
topology term refers to both the physical and logical layout of a network.
o Network topologies refer to the arrangement and connection patterns of computers in the network.
o It is the physical layout of the terminals, links, and computers in the network.
o Network topology can be defined as the cabling structure or geographical arrangement of computers
in the network.
o Network topology can be defined as the cabling structure of the geographical arrangement of
computers in a Local Area is known as Network Topology or LAN Topology.
Network topologies are of several types. Some topologies used in LAN are as follows:
o Bus or Linear topology
o Star Topology
o Ring Topology
o Tree Topology
o Mesh Topology
Bus or linear topology
o In this type of topology, all the nodes (computers as well as servers) are connected to a single cable
with the help of interface connectors.
o This central cable is called the backbone of the network and is known as Bus.
o Every workstation communicates with the other devices through this Bus.
o It’s every end has a terminator and the terminator stops the flow of data out of the bus.
o In this network, if the cable breaks, it affects the whole network.
o There is a maximum chance of collision of data.
Advantages of Bus Topology
It is easy to set up and extend.
Bus topology is comparatively cheaper.
The cable length is required for this topology is the least compared to other networks.
Linear Bus network is mostly used in small networks.
Disadvantages of Bus Topology
If the main cable (i.e. bus) encounters any problem, the whole network breaks down.
There is a maximum chance of collision of data.
It is difficult to detect and troubleshoot fault at the individual stations.
CN- UNIT V Page 1
,Ring Topology
o In a ring network, every device has exactly two neighboring devices for communication purpose.
o It is called a ring topology as its formation is like a ring. In this topology, every computer is
connected to another computer.
o Here, the last node is combined with a first one.
o This topology uses token to pass the information from one computer to another. In this topology, all
the messages travel through a ring in the same direction.
Advantages:
Easy to install and reconfigure.
Adding or deleting a device in-ring topology needs you to move only two connections.
The troubleshooting process is difficult in a ring topology.
Failure of one computer can disturb the whole network.
Offers equal access to all the computers of the networks
Faster error checking and acknowledgment.
Disadvantages:
Unidirectional traffic.
Break in a single ring can risk the breaking of the entire network
Modern days high-speed LANs made this topology less popular.
In the ring, topology signals are circulating at all times, which develops unwanted power
consumption.
It is very difficult to troubleshoot the ring network.
Adding or removing the computers can disturb the network activity.
Star Topology
o This is the most commonly used and popular topologies in LAN.
o In this topology, all the components of the network are connected to the central device (which may
be a hub, a router, or a switch).
o This hub is the central node and all other nodes are connected to the central node.
o In the star topology, all the computers connect with the help of a hub.
o This cable is called a central node, and all other nodes are connected using this central node.
o It is most popular on LAN networks as they are inexpensive and easy to install.
CN- UNIT V Page 2
, Advantages:
Easy to troubleshoot, set up, and modify.
Only those nodes are affected, that has failed. Other nodes still work.
Fast performance with few nodes and very low network traffic.
In Star topology, addition, deletion, and moving of the devices are easy.
Disadvantages:
If the hub or concentrator fails, attached nodes are disabled.
Cost of installation of star topology is costly.
Heavy network traffic can sometimes slow the bus considerably.
Performance depends on the hub’s capacity
A damaged cable or lack of proper termination may bring the network down.
Mesh Topology
o The mesh topology has a unique network design in which each computer on the network connects to
every other
o It is develops a P2P (point-to-point) connection between all the devices of the network.
o It offers a high level of redundancy, so even if one network cable fails, still data has an alternative
path to reach its destination.
o Mesh topologies involve the concept of routes.
o In a mesh network, every device connects to every other by a communication cable. The control is
distributed with each node deciding its communication priorities.
CN- UNIT V Page 3
