NETWORK TOPOLOGIES: CONCEPT, TYPES AND THEIR CHARACTERISTICS, EXAMPLES - TECHNOLOGY - 2025

Network topologies are the different layouts of devices, such as routers, computers, printers, and the different connections that may exist on the network. They can be illustrated graphically.

Therefore, they refer to the physical or logical design of a computer network. They define the way the different nodes are placed and how they interconnect with each other. Similarly, they can describe how data is transferred between these nodes.

Source: By SilverStartalk - Made using Dia, CC BY 2.5, Both the network topology and the relative locations of the source and destination of traffic flows on the network determine the optimal path for each flow and the extent to which there are redundant options to be able to route in the event of failure.

There are two types of network topologies. The logical topology is based on the data transfer model through the different devices on the network. On the other hand, the physical topology is based on the physical design of the computers connected in the network.

Organization of a network

The topology of a network is very important in determining its performance. It is the way a network is organized, it contains the logical or physical description of how devices and connections are configured to link together.

There are numerous ways to organize a network, each with different advantages and disadvantages, some being more useful than others in certain circumstances.

Concept

Network topologies refer to how the various devices and connections on the network are organized among themselves. You can consider the network as a city and the topology as the route map.

Just as there are many ways to organize and maintain a city, such as ensuring that roads can facilitate passage between the parts of the city that host the most traffic, there are several ways to organize a network.

Each topology has its advantages and disadvantages. According to the organization's requirements, certain configurations can offer a higher level of security and connectivity.

A topology should be considered as the virtual structure of a network. This shape does not necessarily correspond to the actual physical layout of the devices on the network.

You can think of computers on a home network, which could be arranged in a circle. However, it is hardly feasible to have a ring topology there.

Choice of topology

Managers have a set of alternatives when looking to implement a topology for the network. This decision must consider the proportion of the company, its budget and its objectives.

Different activities arise in the practical administration of network topology, such as general supervision of operation, visual representation and management of the topology.

The most important thing is to understand the needs and goals to establish and manage the network configuration in the most appropriate way for the company.

Choosing the correct configuration for an organization's operating model can improve performance, as well as facilitate troubleshooting, troubleshooting, and more efficient allocation of network resources to ensure excellent network health.

Importance

Network design is important for several reasons. Mainly, it has a fundamental role in how well and how the network will work.

A well-managed network topology improves data and power efficiency, which will help lower maintenance and operating costs.

The layout and design of a network is exhibited through a diagram created by network topology software.

These diagrams are critical for a number of reasons, especially the way they can provide a visual representation of physical and logical designs, allowing administrators, when troubleshooting, to see the connections between devices.

The way a network is organized can make or break network connectivity, functionality, and protection against downtime.

Types and their characteristics

- Physical topologies

It refers to the design of the interconnections between devices and the physical connections of the network, such as cable (DSL, Ethernet), microwave or fiber optics.

There are several common physical topologies, as shown in the following illustration and described later.

Source: Jugandi

Bus network

Each device is connected in series along a linear path. This arrangement is found today mainly in broadband wired distribution networks.

Star network

In this network, a central device is directly connected to all other devices. Local area networks (LANs) that use Ethernet switches, such as most wired office networks, have a star configuration.

Ring network

In this configuration the devices are connected in a network as a circle. Some networks will send the signal in only one direction and others will be able to send the signal in both directions.

These bi-directional networks are more robust than bus networks, since the signal can move in either direction to reach a device.

Mesh net

This network links the connections to the devices in such a way that multiple routes are available between at least some points in the network.

A network is partially meshed when only some devices are connected to others, and fully meshed when all devices have a direct connection to all others.

Multi-path mesh increases resistance to failure, but also increases cost.

Tree net

Also called star of stars, it is a network where different star topologies are connected in a star configuration.

Many large Ethernet switch networks, such as networks between different data centers, are tree-like.

Hybrid network

It is a mix of two or more topologies. For example, if one office uses a bus topology and another office uses a star topology, connecting these two topologies will result in a hybrid topology: bus topology and star topology.

- Logical topologies

The logical topology for a network is somewhat more strategic and abstract. It generally consists of achieving a conceptual understanding of how and why the network is organized the way it is, and how data moves through it. It refers to the logical relationship between devices and connections.

A logical connection will differ from a physical route when information can make an invisible jump at intermediate points.

In optical networks, optical multiplexers (ADMs) create logical optical paths, because the ADM hop is not visible to the endpoint nodes.

Networks made up of virtual circuits will have a physical topology according to the real connection area, such as the cable, and a logical topology based on the circuits.

Sometimes the logical topology corresponds to the configuration as the user sees it, which means network connectivity.

IP and Ethernet networks

The two most widely used networks today, IP and Ethernet, are fully interwoven at the connection level because any user can connect to anyone else, unless some means, such as a firewall, is introduced to block unwanted connections.

The total connectivity is due to the protocols that are handled in the network, such as Ethernet, and not of the physical topology of the network as such. For this reason, any physical network topology may appear to people to be fully interlaced.

Examples

Bus network

Bus network topologies based on Ethernet cabling are relatively easy and inexpensive to install, although spans are limited by the maximum length of cable available.

For example, suppose a bus network that is made up of four computers: PC-A, PC-B, PC-C, and PC-D.

If PC-A sends data to PC-C, then all computers on the network will receive this data, but only PC-C will accept it. If PC-C responds, only PC-A will accept the returned data.

By joining two bus cables, expansion can be achieved, but this topology works best with a limited number of devices, typically fewer than twelve devices on a single bus.

Star network

Star network topologies are common in home networks, where the central connection point can be a router or network hub.

Unshielded twisted pair (UTP) Ethernet cabling is generally used to connect devices to the hub, although coaxial or fiber optic cable can also be used.

When confronted with the bus topology, a star network generally requires a greater amount of cabling.

Ring network

Ring network topologies are most commonly found in universities, although they are also used by some commercial companies.

Like the bus topology, this topology is no longer valid in recent networks. IBM implemented it in principle to be able to overcome the existing drawbacks of the bus topology.

If you have a large number of devices connected, repeaters should be used to "refresh" the data signals as they travel through the network.

Mesh net

Mesh network topologies are typical of the Internet and certain wide area networks (WANs).

The data can be transmitted through routing logic, which is determined by established criteria such as "avoid broken links" or "the route with the shortest distance".

Tree net

It is often used in wide area networks (WAN). They are ideal for group workstations.

You can easily achieve and maintain device expansion by extending bus and star topologies.

Error detection is also straightforward, but these systems tend to be cable-intensive and cost-intensive.

References

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