Why do networks have different topologies

However, where each node in a star topology is directly connected to the central hub, a tree topology has a parent-child hierarchy to how the nodes are connected.

Those connected to the central hub are connected linearly to other nodes, so two connected nodes only share one mutual connection. Combining elements of the star and bus topologies allows for the easy addition of nodes and network expansion. Troubleshooting errors on the network is also a straightforward process, as each of the branches can be individually assessed for performance issues. As with the star topology, the entire network depends on the health of the root node in a tree topology structure.

Should the central hub fail, the various node branches will become disconnected, though connectivity within—but not between—branch systems will remain. Because of the hierarchical complexity and linear structure of the network layout, adding more nodes to a tree topology can quickly make proper management an unwieldy, not to mention costly, experience.

Tree topologies are expensive because of the sheer amount of cabling required to connect each device to the next within the hierarchical layout. A mesh topology is an intricate and elaborate structure of point-to-point connections where the nodes are interconnected. Mesh networks can be full or partial mesh. Partial mesh topologies are mostly interconnected, with a few nodes with only two or three connections, while full-mesh topologies are—surprise! The web-like structure of mesh topologies offers two different methods of data transmission: routing and flooding.

When data is routed, the nodes use logic to determine the shortest distance from the source to destination, and when data is flooded, the information is sent to all nodes within the network without the need for routing logic. Mesh topologies are reliable and stable, and the complex degree of interconnectivity between nodes makes the network resistant to failure. For instance, no single device going down can bring the network offline.

Mesh topologies are incredibly labor-intensive. Each interconnection between nodes requires a cable and configuration once deployed, so it can also be time-consuming to set up.

As with other topology structures, the cost of cabling adds up fast, and to say mesh networks require a lot of cabling is an understatement. Hybrid topologies combine two or more different topology structures—the tree topology is a good example, integrating the bus and star layouts.

Hybrid structures are most commonly found in larger companies where individual departments have personalized network topologies adapted to suit their needs and network usage.

However, each type of network topology comes with its own disadvantages, and as a network grows in complexity, so too does the experience and know-how required on the part of the admins to keep everything functioning optimally. No network topology is perfect, or even inherently better than the others, so determining the right structure for your business will depend on the needs and size of your network.

Here are the key elements to consider:. The bus and star topologies are on the simpler side of things, both being fairly lightweight, while mesh networks are much more cable- and labor-intensive.

Coaxial and twisted-pair cables both use insulated copper or copper-based wiring, while fiber-optic cables are made from thin and pliable plastic or glass tubes. Twisted-pair cables are cost-effective but have less bandwidth than coaxial cables.

Fiber-optic cables are high performing and can transmit data far faster than twisted-pair or coaxial cables, but they also tend to be far more expensive to install, because they require additional components like optical receivers. Determining the right topology for your needs, then, is a matter of striking the right balance between installation and operating costs and the level of performance you require from the network.

The last element to consider is scalability. Star topologies are so common because they allow you to add, remove, and alter nodes with minimal disruption to the rest of the network. Ring networks, on the other hand, have to be taken entirely offline for any changes to be made to any of the nodes. They allow you to see how the information will move across the network, which, in turn, allows you to predict potential choke points. Visual representation makes it easier to create a streamlined and efficient network design, while also acting as a good reference point if you find yourself needing to troubleshoot errors.

There are a few network topology mapping products on the market. C Language. Advanced Data Structure. Operating System. Computer Network. Computer Architecture. Android Development. Game Development. GO Language. Spring Framework. Go to Tutorials Library. In networks with ring topology, computers are connected to each other in a circular format. Every device in the network will have two neighbors and no more or no less. Ring topologies were commonly used in the past but you would be hard-pressed to find an enterprise still using them today.

The first node is connected to the last node to link the loop together. As a consequence of being laid out in this format packets need to travel through all network nodes on the way to their destination.

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.

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. See also: Tools To Monitor Throughput. A star topology is a topology where every node in the network is connected to one central switch.

Every device in the network is directly connected to the switch and indirectly connected to every other node. The relationship between these elements is that the central network hub is a server and other devices are treated as clients.

The central node has the responsibility of managing data transmissions across the whole network and acts as a repeater.

With star topologies, computers are connected with a coaxial cable, twisted pair, or optical fiber cable. Star topologies are most commonly-used because you can manage the entire network from one location : the central switch. Likewise, you can add new computers without having to take the network offline like you would have to do with a ring topology. In terms of physical network structure, star topologies require fewer cables than other topology types.

This makes them simple to set up and manage over the long-term. The simplicity of the overall network design makes it much easier for administrators to run troubleshooting when dealing with network performance faults.

Though star topologies may be relatively safe from failure, if the central switch goes down then the entire network will go down. Star topologies are easy to manage in most ways but they are far from cheap to set up and use. As the name suggests, a tree topology network is a structure that is shaped like a tree with its many branches. Tree topologies have a root node that is connected to another node hierarchy. The hierarchy is parent-child where there is only one mutual connection between two connected nodes.

As a general rule, a tree topology needs to have three levels to the hierarchy to be classified this way. The hub can be passive in nature i. Active hubs have repeaters in them. Figure 2 : A star topology having four systems connected to a single point of connection i. So, it is easy to set up. Each device requires only 1 port i. Problems with this topology : If the concentrator hub on which the whole topology relies fails, the whole system will crash down. The cost of installation is high.

Performance is based on the single concentrator i. It transmits the data from one end to another in a single direction. No bi-directional feature is in bus topology. It is a multi-point connection and a non-robust topology because if the backbone fails the topology crashes. Figure 3 : A bus topology with shared backbone cable. The nodes are connected to the channel via drop lines.

Advantages of this topology : If N devices are connected to each other in a bus topology, then the number of cables required to connect them is 1, which is known as backbone cable, and N drop lines are required.

The cost of the cable is less as compared to other topologies, but it is used to build small networks.