Difference Between Star and Mesh Topology

Star and mesh topology are the types of the topologies where star topology comes under the peer-to-peer transmission and mesh topology works as a primary-secondary transmission. However, these topologies mainly differ in the physical and logical arrangement of the connected devices. The star topology organises the devices around the central controller known as the hub. On the other hand, the mesh topology connects each device to another device with a point-to-point link.

Content: Star Topology Vs Mesh Topology

1. 1. Comparison Chart
   2. Definition
   3. Key Differences
   4. Advantages
   5. Disadvantages
   6. Conclusion

Comparison Chart

Basis for comparison	Star Topology	Mesh Topology
Organisation	The peripheral nodes are connected to the central node(ex. hub, switch or router).	It contains at least two nodes with two or more paths between them.
Installation and reconfiguration	Easier	Difficult
Cost	Comparatively less	Expensive due to extensive cabling.
Robustness	Intermediate	Highly robust
Cabling requirements	Uses twisted pair cables which cover distance up to 100 meters.	Twisted pair, coaxial, fibre optic cable, any of the cable type can be used depending on the type of networks.
Routing mechanism	All the information is routed from the central network connection.	Information is directly routed from one device to another.
Complexity	Simple	Quite complex
Scalability	Good	Poor

Definition of Star Topology

The Star topology connects all of the end devices to a common central node directly. A central controller which is connected to all the other devices through point-to-point links is called a star coupler. It does not flow the traffic between the devices instead the star coupler acts as the mediator, for employing the exchange of the data. If a device wants to communicate or send data to another device, priorly it has to send data to the central controller. Then the central controller relays the data to the intended destination.

The central controller can work in two manners:

• In the first approach, it can broadcast the frames to the central node and then central node retransmit it on all the external links so that it can reach to the final node. In this scenario, the organisation of the network nodes looks like star physically, but these are connected in a bus topology, where all the other nodes receive the transmitted data.
• The second approach includes switching and routing functions where the central star coupler behaves as a frame-switching device. In this type, the central node buffers the arriving frame then retransmit it to the destination node.

The star topology enables the high-speed data transfer especially when the central controller is utilized as a switch. Here the number of links is equal to the number of nodes. This topology is flexible and maintained efficiently, as compared to other topologies.

Definition of Mesh Topology

Mesh topology links the node in a way that each node is linked to the other node by a dedicated point-to-point link. Therefore, it creates n(n-1)/2 links to connect n number of nodes, which is a bit too much. The form of media used to link the nodes can be twisted pair, coaxial, or optical fibre cable. This type of topology does not require any additional information about the packet such as the source address or destination address because two nodes are connected directly.

The flexibility of the mesh topology is very low and has a poor scalability factor. It requires laying of the links to add a new node so that the new node could be connected to each existing node. This is the reason it is very expensive topology.

Advantages of the Star Topology

• It reduces the transferring of the packets from the excessive number of nodes.
• The nodes are inherently isolated from each other.
• Central hub facilitates the easy addition of the new devices.
• It is easy to understand, install and navigate.
• Faulty parts can be easily detected and eliminated.
• It is interference free at the time of adding and removing devices.

Advantages of the Mesh Topology

• The node organisation in mesh topology helps in more than one transmission of data from one node to another node simultaneously.
• Provides privacy and security with the point-to-point links.
• It is robust, failure of one link does not affect the other system.
• Fault identification and isolation are also easy.

Disadvantages of the Star Topology

• The functioning of the system highly depends upon the central hub.
• Any lapse in the central hub can result in the inoperability of the entire system.
• Scalability relies on the capability of the central hub.

Disadvantages of the Mesh Topology

• This network configuration can create redundant network connections, as there are some connections which are useless.
• The overall cost of the topology is also increased because of an excessive amount of cabling and need of i/o ports.
• Wiring is complex.

Conclusion

Star topology is efficient in terms of the cost while the mesh is a good option when the security and speed of the data transmission is the concern.