Last Updated on January 10, 2023 by Shahzad Arsi

What is the principal function of a switch in networking, and what are the different classes of switches with their corresponding operations?

A switch is a network device that can be useful for connecting multiple devices, such as computers, printers, and servers in a small business network using an Ethernet cable.

By allowing sharing of all information and facilitating communication between them they provide versatility in providing connectivity while also allowing efficient data transfer across multiple systems.

Wherever possible it should be placed to maximize its functionality within the office space or building layout.

What is Switch in Computer Network

A switch is a networking device that helps to connect devices in a network. A switch helps to move data between devices more quickly and easily.

Switches play a major role in connecting computers that host virtual machines in a data center with physical servers, as well as with storage infrastructure. They also help to move a large amount of network traffic through telecommunications provider networks.

Types of Network Switches

There are different types and categories of switches in networking. Below, we will explain each one.

KVM Switches

Fixed-Configuration Switches

Unmanaged Switches

Managed Switches

Smart Managed Switches

Modular Switches

Stackable Switches

Ethernet Switches

PoE Switch

Enterprise managed switches

Data Center Switches

KVM switches

 KVM Switches are switches that allow you to control multiple computers from a single keyboard, mouse, and monitor. Fixed-configuration switches are switches that have a specific purpose and cannot be changed.

Unmanaged switches are switches that do not require any configuration. Managed switches are switches that can be configured by the user. Smart managed switches are managed switches with additional features, such as monitoring and managing traffic.

Modular switches are switches that can be stacked together, and Ethernet switches are switches that use Ethernet cables to transmit data. PoE switches are switches that provide power over Ethernet cables, and enterprise-managed switches are switches that are managed by an enterprise network administrator. Datacenter switches are switches that are used in data centers.

Parts of CPU and their functions

Example of Switch in Networking

An example of a KVM switch is one that allows you to connect multiple keyboards, video, and mouse devices to a single computer. KVM switches also help to save PC space by eliminating wires.

These switches act as a simple interface to allow individual users to handle the various functions of multiple systems using just one console. They have a few special key keyboard shortcuts, so you can easily connect your computers to a keyboard and mouse. You can also scale the reach of the switch by using a KVM extender, which will transmit DVI, VGA, or HDMI signals. KVM switches offer the best option for accessing local and remote machines, as well as for centrally managing servers.

Fixed-Configuration Switches

Fixed-Configuration Switches are less expensive and have a limited number of ports, so they are ideal for small businesses or home networks.  They come in two varieties: the Wall Switch and the Desktop Switch. The Wall Switch plugs into a wall outlet, and the Desktop Switch is a small, handy box that you can place on your desk.

Both types of switches have one port and one switch port, which means that you can only use one device at a time. The downside of fixed-configuration switches is that you cannot add or remove ports, so they are not good for growing networks.

A network switch is a hardware device that is used to connect devices in a computer network. Network switches allow computers to share resources such as printers, file servers, and Internet connections.

There are three types of switches: unmanaged, managed, and stackable.

Unmanaged Switches:

Mostly, these switches are used in the home networks or small companies  Unmanaged switches are not managed and do not have a built-in management system. They are also known as “dumb” switches.

Switches are devices that allow multiple devices to connect to a network. They are also known as “dumb” switches because they do not have a lot of features, such as being able to manage traffic or being able to act as a router.

Managed switches

Switches that are managed provide features that can be customized to improve the functionality of a specific network. These features include Quality of Service (QoS), Simple Network Management Protocol (SNMP), and more. They offer many advanced features that can be controlled by professional administrators and are often used in networking devices such as VLANs.

Managed Switches: Managed switches are the most popular type of switch. They come with a management system that allows you to configure and manage the switch remotely.

Smart Managed Switches: A switch is a networking device that is used to connect devices in a network. A smart-managed switch is a type of switch that is designed to manage and optimize the traffic in a network.

These switches provide limited management abilities, such as configuring VLANs, speed/duplex control, and SNMP settings. They are best used in home networks or small businesses where simplicity is key. They allow users to easily switch between devices without having to go through a router.

Modular Switches

With modular switches, you can add expansion modules to meet your specific networking requirements. This gives you much flexibility to change your network as needed. Expansion modules are designed for specific applications, such as firewalls, wireless connectivity, and network analysis. By adding these modules, you can add additional interfaces, power supplies, and cooling fans. However, keep in mind that this can increase the cost of the switch.

Stackable Switches:

Stackable switches are a new type of switch that allows you to stack multiple switches together to create a large network switch. This is ideal for large businesses or home networks.

Stackable switches are switches that can be combined to act as a single switch. This is done by connecting the switches together at the rear edge using special wires. This allows the switches to communicate with each other and perform all tasks like a single unit, but with extra ports.

The switch has 384 ports and can handle all the functions of a single switch.

Cisco 350X series models can be used as standalone switches.

Ethernet Switches

Ethernet switches are also known as LAN switches. LAN switches help to deliver the broadcasted data packets before getting directions to its embedded receiver. These switches can decrease network congestion or bottlenecks by distributing a package of data only to its intended recipient.

PoE Switches

PoE switches are switches that provide power over Ethernet. This means that they provide power to devices on the network through the Ethernet cables. This can be useful for devices that do not have a power cable nearby, such as IP cameras and smart lighting systems. PoE switches also transmit data between devices, so there is no need for a separate data cable.

PoE switches help create a PoE network environment that can support both Ethernet and PoE-enabled devices.

Enterprise Switches

Enterprise Switches are used to manage and monitor users and all devices which are connected at the edges to secure each connection point from potential security problems. These types of network switches have specific abilities such as PoE function, and with using of PoE technology, these switches are capable to handle the energy consumption of several edge network devices linked to switches.

Functions and Uses of Switches

There are four basic functions of switches in networking:

1. Forwarding packets between devices

When devices are connected to a network, they need to be able to send and receive packets. Switches are used to manage the flow of packets between devices on the network.

 2. Filtering packets based on their destination address

A switch in a network can be used to filter packets based on their destination address. This is done by looking at the destination address of the packet and deciding whether or not to send it on its way. If the destination address is not on the switch’s configured list of allowed addresses, then the packet is not sent on its way.

3. Flooding packets out all other ports except the one they were received on

In a network, packets flow from one device to another. When a packet arrives at a device, the device looks for the destination address of the packet. If the destination address is not found, the device looks for the source address of the packet. The device then sends the packet to the appropriate port on the device where the destination address is found.

4. Learning the MAC addresses of devices connected to the switch

When configuring a switch, it is important to know the mac addresses of the devices connected to it. This is done by using the ‘show mac-address-table command. This command will show all the mac addresses that are currently active on the switch.

Connect with multiple hosts at a time

To connect to multiple hosts, a network switch with many ports is used to create a star topology. This also allows links between computers and the network system.

Ability to send messages to specific host

If a switch tries to send a message to another host over the same network, it will obtain and decode the frames forgetting to read the MAC address part of the message.

Helps in controlling traffic

Network traffic can be controlled by switches to help manage both inbound and outbound traffic, as well as connecting multiple devices on a network.

Improves Lan Bandwidth

Network switches improve the LAN network’s bandwidth by dividing it into several collision domains and providing independent broadband.

Network switches can regenerate an undistorted square electrical signal while forwarding frames.

Switches help to operate at multiple OSI model layers, like data link, network, or transport layers. Devices that operate simultaneously at multiple layers are known as “Multilayer Switch”.

Functions of Layer 2 Switching

There are three main functions of a layer 2 switch in networking: –

More Helpful Resource

Advantage and disadvantages of a laser printer

Advantage and disadvantage of twisted pair cable

Batch processing in an operating system

Computer output devices and their functions

How to connect coaxial without connectors

Forwarding packets between devices –

When you want to send data from one device to another, you need to use a network switch. Switches allow you to send packets between devices by forwarding them. Packets are pieces of information that are sent through the network.

Filtering packets based on MAC addresses –

One function of switches in networking is to filter packets based on their destination addresses. Switches use a process called port mapping to determine the destination address of each packet. By knowing the destination address, switches can filter packets based on their intended destination.

Creating a collision domain

When two switches are in close proximity to each other, they can create a collision domain. This can cause problems with communication and data loss. To avoid this, it is important to configure your switches to avoid creating a collision domain.

Helps in Address learning

The Address Learning process in a network switch involves retrieving the MAC address of devices connected to the network, and if a frame arrives at a port on the switch, the process of looking up the MAC address in a table and adding it if not found.

If the switch does not have an entry for the MAC address in the table, it will append the address and port number to the table from the frame that was received.

If the MAC address table already contains the MAC address, the network switch will compare the incoming port number with the port number that is already in the MAC table.

If the port numbers are not a match, then the network switch will update the MAC address table with the new updated port number. This issue can occur when a network administrator removes the cable from one port and then connects it to another port.

Helps in forwarding & filtering decision

In the forwarding process, all traffic is sent from one port on a switch to another device connected to that port.

The destination MAC address is used to identify the port number to which the target device is connected.

If the destination MAC address is not found in the MAC address table, the switch will flood the frame out of all other ports except the port from which the frame was received.

Normally, flooding is caused when a network switch starts up and begins to learn the addresses of devices connected to it. This can be prevented by discarding network traffic when the switch is starting up.

If the source MAC address matches the destination MAC address, the switch will filter the Ethernet frame.

Helps in avoiding loop

In a LAN network, redundant links are created to prevent a complete network failure in the event of a single link failure. Network switches are used to avoid layer 2 switching loops and broadcast storms.

Store and forward

These switches are able to store and check every packet before routing.

Cut through network

Network switch uses a technique called cut-through to verify the part of the packet header to the hardware address of the frame before forwarding it. They have to store and forward techniques while the outgoing port is getting busy with other packets.

Fragment Free network:

Fragment-free verifies the first 64 bytes of a packet to store all addressing information, preventing erroneous packet frames from routing.

Adaptive switching network

Adaptive switching is a technique that allows the network to choose one of the three methods mentioned above, depending on the traffic situation.

Working of Switch in Networking

If, in your mind is arisen one question is working of switch in networking

How Does an Ethernet Switch Work?

An Ethernet switch forwards packets based on the destination MAC address. When a packet is received, the switch looks up the destination MAC address in its routing table. If the destination MAC address is found, the switch sends the packet to the correct port on the switch. If the destination MAC address is not found, the switch looks up the source MAC address in its routing table. If the source MAC address is found, the switch sends the packet to the correct port on the switch.

There are four steps involved in the working of a network switch:

Obtained packets 

An Ethernet switch forwards packets between devices on the data link layer and also generates packets from IPs. These packets are then placed into Ethernet frames. 

Switches are devices that allow communication between different parts of a network. They do this by taking packets and placing them into Ethernet frames. Ethernet is a type of networking protocol that uses packets to send data.

Encapsulation:  

The bits adhere to the front and back of the packet.

When two devices are connected to a network, they need to communicate with each other. The devices need to send and receive data packets. When the devices are connected to the network, they need to send and receive data packets through switches. Switches are used to send and receive data packets.

Switches are also used to manage network traffic. They allow multiple devices to share one connection, and they can be used to connect different parts of a network. 

The MAC address is the unique identifier for a network interface on a computer. Switches use the MAC address to send packets to the correct port on the switch.

 Switches help manage traffic on a network. They allow multiple devices to share one connection, and they can be used to connect different parts of a network. Switches use the MAC address to send packets to the correct port on the switch.

Processing Identifying Data: 

The header of a frame includes key identifying data, such as the source and destination MAC addresses. When a frame reaches a network switch, the switch extracts all the information and determines where to send it via ports to its targeted destination.  

In order for a computer to send information to another computer, it needs to know where to send the information. There are a few ways this can be done. One way is to use ports. Ports are specific locations on a computer where information can be sent. 

Ports are specific locations on a computer where information can be sent. Ports allow different devices to connect to the computer and can be used for a variety of purposes, such as connecting a printer to a computer or connecting a game console to the computer.

Forwarding Packet: 

A-frame reaches an intended device, and then it obtains the packet and strips it.

When A-Frame is running on a device, it will often be in an environment where it is constantly communicating with other devices. In order to make sure that packets are being sent to the intended device, A-Frame will often strip the packet before sending it.