Type of Network topologies: Ring, tree, mesh and hybrid

 Ring topology:

In ring topology, each host device connects to exactly two other devices, creating a circular network structure. When one host tries to communicate or send message to a host which is not adjacent to it, the data travels through all intermediate hosts.

                     Fig. 1: Ring topology.

Advantages of Ring topology:

·       Network Management: Faulty devices can be removed from the network without bringing the network down.

·       Product availability: Many hardware and software tools for network operation and monitoring are available.

·       Cost: Twisted pair cabling is inexpensive and easily available. Therefore, the installation cost is very low.

·       Reliable: It is a more reliable network because the communication system is not dependent on the single host computer.

Disadvantages of Ring topology:

·       Difficult troubleshooting: It requires specialized test equipment to determine the cable faults. If any fault occurs in the cable, then it would disrupt the communication for all the nodes.

·       Failure: The breakdown in one station leads to the failure of the overall network.

·       Reconfiguration difficult: Adding new devices to the network would slow down the network.

·       Delay: Communication delay is directly proportional to the number of nodes. Adding new devices increases the communication delay.

 

 Tree topology:

This topology is the extension of Star topology and also known as hierarchical topology. In this topology, the various secondary hubs or devices are connected to the central hub or device which contains the repeater. In this data flow from top to bottom i.e., from the central hub or device to secondary and then to the devices or from bottom to top i.e., devices to the secondary hub and then to the central hub. It is a multi-point connection and a non-robust topology because if the backbone fails the topology crashes.

                       Fig.2: Tree topology.

Advantages of Tree topology:

Support for broadband transmission: Tree topology is mainly used to provide broadband transmission, i.e., signals are sent over long distances without being attenuated.

Easily expandable: We can add the new device to the existing network. Therefore, we can say that tree topology is easily expandable.

Easily manageable: In tree topology, the whole network is divided into segments known as star networks which can be easily managed and maintained.

Error detection: Error detection and error correction are very easy in a tree topology.

Limited failure: The breakdown in one station does not affect the entire network.

Point-to-point wiring: It has point-to-point wiring for individual segments.

Disadvantages of Tree topology:

Difficult troubleshooting: If any fault occurs in the node, then it becomes difficult to troubleshoot the problem.

High cost: Devices required for broadband transmission are very costly.

Failure: A tree topology mainly relies on main bus cable and failure in main bus cable will damage the overall network.

Reconfiguration difficult: If new devices are added, then it becomes difficult to reconfigure.

Mesh topology:

In mesh topology, a host device is connected to one or multiple hosts devices. This topology has hosts in point-to-point connection with every other host or may also have hosts which are in point-to-point connection to few hosts only.

                     Fig. 3: Mesh topology.

Advantages of Mesh topology:

Reliable: The mesh topology networks are very reliable as if any link breakdown will not affect the communication between connected computers.

Fast Communication: Communication is very fast between the nodes.

Easier Reconfiguration: Adding new devices would not disrupt the communication between other devices.

Disadvantages of Mesh topology:

Cost: A mesh topology contains a large number of connected devices such as a router and more transmission media than other topologies.

Management: Mesh topology networks are very large and very difficult to maintain and manage. If the network is not monitored carefully, then the communication link failure goes undetected.

Efficiency: In this topology, redundant connections are high that reduces the efficiency of the network.

 

Hybrid topology:

When two or more different topologies are combined together is termed as hybrid topology. The combination of various different topologies is known as hybrid topology.

                    Fig. 4: Hybrid topology.

Advantages of Hybrid topology:

Reliable: If a fault occurs in any part of the network will not affect the functioning of the rest of the network.

Scalable: Size of the network can be easily expanded by adding new devices without affecting the functionality of the existing network.

Flexible: This topology is very flexible as it can be designed according to the requirements of the organization.

Effective: Hybrid topology is very effective as it can be designed in such a way that the strength of the network is maximized and weakness of the network is minimized.

Disadvantages of Hybrid topology:

Complex design: The major drawback of the Hybrid topology is the design of the Hybrid network. It is very difficult to design the architecture of the Hybrid network.

Costly Hub: The Hubs used in the Hybrid topology are very expensive as these hubs are different from usual Hubs used in other topologies.

Costly infrastructure: The infrastructure cost is very high as a hybrid network requires a lot of cabling, network devices, etc.