Learn the basics of Ethernet switches

2023.04.05

Learn the basics of Ethernet switches

Although an Ethernet switch looks simple, it's not as simple as we've seen. For example, technology and procurement professionals are often unaware of how Ethernet switches work, how they differ from Ethernet hubs, and what to consider when selecting an Ethernet switch for a specific application.

Ethernet switches have become an important part of computer networks. It is a networking device that centralizes communication between devices connected in a local area network (LAN). It manages the flow of data in a network by receiving and transmitting packets of data between devices such as computers, printers, and scanners.

However, although an Ethernet switch looks simple, it is not as simple as we see it. For example, technology and procurement professionals are often unaware of how Ethernet switches work, how they differ from Ethernet hubs, and what to consider when selecting an Ethernet switch for a specific application.

This article covers all of that and more. It will serve as a guide for those who wish to understand the basics of Ethernet switches.

How does an Ethernet switch work?

When a technician connects a device to an Ethernet switch using a data cable, the switch identifies all devices by their Media Access Control (MAC) address. This allows the switch to map all Ethernet devices connected to its ports.

Suppose one of the devices (say a laptop) intends to send a packet of data through an ethernet switch to another device (say a printer) on the network. In this case, when a packet of data enters the switch, the switch reads the packet's header to determine its source MAC address (where it came from) and destination MAC address.

Next, the switch sends the packet out through the port leading to the device with the destination MAC address.

Ethernet Switch vs Hub vs Router: What's the Difference?

Ethernet hubs are very similar to Ethernet switches: they connect devices on a network. However, unlike Ethernet switches, hubs do not distinguish between MAC addresses in the network during operation. Instead, it simply broadcasts packets from the source device to all other connected devices in the hub.

Due to its mode of operation and the transmission of unnecessary data to all ports, hubs often place a large amount of traffic on the network, causing users to experience poor network response times. Also, an Ethernet hub shares its bandwidth with each port, unlike an Ethernet switch which allocates the full bandwidth to each of its ports.

In contrast, a router is a networking device that connects different networks. It is very similar in function to a switch, but differs in that it has many more functions. For example, it uses network address information to forward packets from a source network to a destination network.

What factors need to be considered when choosing an Ethernet switch?

Ethernet switches come in different designs, and each type has its unique size, features, capabilities, and suitability for different applications. Therefore, users must consider several factors when selecting an Ethernet switch for a particular application.

Number of ports

Ethernet switches typically come in 5, 8, 10, 24, 48 and 54 port configurations. The ideal number of ports depends primarily on the number of physical devices (laptops, printers, and phones), network devices, and security devices that will be connected to the switch. In general, it is recommended that technology and procurement professionals select switches with more ports than are required to allow for future additions of equipment.

speed

Ethernet switches are typically designed for transmission speeds from 100 Mbps to 10 Gbps. The user should select the Ethernet speed based on the desired speed requirements.

Power over Ethernet

Power over Ethernet (PoE) is a technology that allows Ethernet cables to transmit both power and data. This allows for flexible installation of equipment in remote locations and areas that lack electrical circuits.

scalability

Purchasing professionals also want to consider the scalability of their network systems when selecting Ethernet switches. For example, more Ethernet switches may need to be added to the initial network system. In this case, they may want to consider stackable switches, which allow multiple switches to be stacked together and operate as a single Ethernet switch.

How to calculate Network Switch Forwarding Rate (NSFR)?

Network forwarding performance or forwarding rate indicates the number of packets forwarded by a switch per second. It provides insight into the performance of network switches.

Ethernet switches can provide several advantages for data transmission and communication in networked systems when properly selected for a particular application. Therefore, it is recommended that technical and procurement professionals contact network switch vendors to discuss their application and specification needs.