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Bus topologies were often used in smaller networks. One of the main reasons is that they keep the layout simple. All devices are connected to a single cable so you don’t need to manage a complex topological setup.

The layout also helped make bus topologies cost-effective because they can be run with a single cable. In the event that more devices need to be added then you could simply join your cable to another cable.

However, relying on one cable does mean that bus topologies have a single point of failure. If the cable fails then the entire network will go down. A cable failure would cost organizations a lot of time while they attempt to resume service. Further to this, high network traffic would decrease network performance because all the data travels through one cable.

This limitation makes bus topologies suitable only for smaller networks. The primary reason is that the more network nodes you have, the slower your transmission speeds are going to be. It is also worth noting that bus topologies are limited in the sense that they are half-duplex, which means that data can’t be transmitted in two opposite directions simultaneously.

In Ring Topology, each computer or node is connected with its neighboring computer forming the shape of ring hence it is known as Ring Topology.In ring topology the data travels in a circular fashion from one computer to another (clockwise or counter clockwise). In case of any failure in a cable or device break the circular loop and can take down the entire network.Within this topology, one node is chosen to configure the network and monitor other devices. Ring topologies are half-duplex but can also be made full-duplex. To make ring topologies full-duplex you would need to have two connections between network nodes to form a Dual Ring Topology. As mentioned above, if ring topologies are configured to be bidirectional then they are referred to as dual ring topologies. Dual ring topologies provide each node with two connections, one in each direction. Thus, data can flow in a clockwise or counterclockwise direction.

With ring topologies, the risk of packet collisions is very low due to the use of token-based protocols, which only allow one station to transmit data at a given time. This is compounded by the fact that data can move through network nodes at high speeds which can be expanded on when more nodes are added.

Dual ring topologies provided an extra layer of protection because they were more resistant to failures. For instance, if a ring goes down within a node then the other ring can step up and back it up. Ring topologies were also low cost to install.

One of the reasons why ring topologies were replaced is because they are very vulnerable to failure. The failure of one node can take the entire network out of operation. This means that ring topology networks need to be constantly managed to ensure that all network nodes are in good health. However, even if the nodes were in good health your network could still be knocked offline by a transmission line failure!

Ring topologies also raised scalability concerns. For instance, bandwidth is shared by all devices within the network. In addition, the more devices that are added to a network the more communication delay the network experiences. This means that the number of devices added to a network topology needed to be monitored carefully to make sure that the network resources weren’t stretched beyond their limit.

Making changes to a ring topology was also complicated because you need to shut down the network to make changes to existing nodes or add new nodes. This is far from ideal as you’ll need to factor in downtime every time you want to make a change to the topological structure!

In Start Topology, all the computers (nodes) go to the central location having a device called as hub. All the devices on the network are connected with a hub device through a link. Each device requires a single wire for the connection to the hub.In star Topology, there exists a point-to-point connection between a node and hub. The hub takes a signal from any node and passes it along to all the other nodes in the network. The hub controls and manages entire function of the network.

Mesh topologies are used first and foremost because they are reliable. The interconnectivity of nodes makes them extremely resistant to failures. There is no single machine failure that could bring down the entire network. The absence of a single point of failure is one of the reasons why this is a popular topology choice. This setup is also secure from being compromised.

However, mesh topologies are far from perfect. They require an immense amount of configuration once they are deployed. The topological layout is more complex than many other topologies and this is reflected by how long it takes to set up. You’ll need to accommodate a whole host of new wiring which can add up to be quite expensive.

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