What Is A Network Switch And Its Types

Knowing the differences between network switches when establishing a corporate network can significantly impact network performance and configuration. But do you know what precisely a network switch is?

A network switch is a hardware device used in computer networking that connects devices together on a single computer network. It operates at the data link layer (Layer 2) of the OSI model and is used to manage and route data within a local area network (LAN).

Table of contents

• What is a network switch?
• How does a network switch work?
• Types of switches in networking
• Features of a network switch
• Advantages of a network switch
• Disadvantages of a network switch

What is a network switch? 

Switch definition: A network switch is a physical device that connects devices, such as computers, printers, etc., in a network and allows them to ‘talk’ by exchanging data packets. 

In layman’s terms, “a network switch connects people, apps, and devices along a network, so they can share and exchange resources.”

Switches have three primary tasks: learn MAC addresses, forward data packets, and protect those packets. A network switch operates on the OSI model‘s network layer 2: the Data Link Layer. But, some switches can forward data through Layer 3, which is required to support virtual LANs (VLANs), which are logical network segments that can cross subnets. Traffic must flow across switches to get from one subnet to another, which is helped by routing capabilities built into the switches.

How does a network switch work? 

When a device is connected to a switch, the switch records the device’s MAC address. The switch uses the MAC address to determine which device sends outgoing packets and where to deliver incoming packets. When a packet enters the switch, it examines its header, compares it to the destination address, and then sends the packet through the relevant ports that lead to the destination devices.

Let’s look at an example to understand better how a network switch works. Assume Computer AB is linked to an Ethernet cable plugged into Port 1 of the switch, Computer CD is connected to Port 2, and Computer EF is connected to Port 3. When data for Computer AB arrives, the switch consults its Content Addressable Memory (CAM) table, determines where Computer AB is connected and learns to route Computer AB-bound traffic to Port 1 rather than Ports 2 or 3. The CAM table might look like this:

Most switches include full-duplex functionality. This functionality allows incoming and outgoing packets to a device to access the total bandwidth of the switch connection to limit the possibility of collisions between network traffic.  

Types of switches in networking 

The size of a switch varies depending on how many devices you need to connect in a particular region, the network speed/bandwidth necessary, etc. So, let’s explore some of the most popular network switch types:

Unmanaged Switch

An unmanaged switch is the most basic sort of switch. They are often plug-and-play, which implies the user has few if any, options. They may have default settings for characteristics like service quality, but they cannot be modified. Unmanaged switches are generally inexpensive, but their lack of features makes them unsuitable for most enterprise applications.

Managed Switch

A managed switch provides greater functionality and capabilities for IT professionals and is more likely to be found in a business or enterprise context. To set up managed switches, use command-line interfaces (CLI). The managed switch’s security is more advanced, securing all forms of traffic they handle. Because of their extensive capabilities make managed switches significantly more expensive than unmanaged ones.

KVM Switch

KVM is an acronym for “Keyboard, Video (monitor), Mouse.” A KVM switch’s primary role is to control, switch between, and administer many PCs or servers using a single keyboard, monitor, and mouse. By allowing you to use numerous computers with a single keyboard, monitor, and mouse, the KVM switch increases productivity, saves space, and saves money. The unique features of these switches allow IT, administrators, to do centralized real-time updating and maintenance.

Smart Switch

Smart or intelligent switches are among the most popular alternatives for managing mid-sized networks. They provide access to switch administration functions like port monitoring, link aggregation, and VPN via a simple Web interface that includes an embedded Web browser. Smart switches are managed switches with additional functionality over an unmanaged switch but fewer than a managed switch. They are more advanced than unmanaged switches but less expensive than fully managed switches.

PoE Switch

A PoE switch, also known as a power over Ethernet switch, is a network switch that uses Power over Ethernet technology. Using a PoE network switch across the Ethernet wire, you can effectively implement the network connectivity and power to supply the PD (powered device). You can use PoE switches in various settings, such as home, business, and outdoors. PoE switch is a handy network switch as it can send power and data simultaneously to several devices.

Features of a network switch 

There are various features of a switch in networking. Let’s go through some of the most popular features:

• It is an intelligent network device that functions as a multiport network bridge.
• Switches use MAC addresses in order to send data packets to designated destination ports.
• Every port on a network switch has the same forwarding or filtering mechanism.
• Switches can perform some error checking before forwarding data to the target port.
• It can communicate in unicast (one-to-one), multicast (many-to-many), and broadcast (one-to-all) modes.
• While forwarding frames, network switches can regenerate an undistorted square electrical signal.
• Switches are active network devices that provide network software and network management features.
• A switch uses packet-switching technology in order to receive and forward data packets from the source to the destination.
• The switch can also create a mirror image of data that can be sent to an external device.
• Network switches divide the LAN network into many collision domains and provide independent broadband, increasing LAN bandwidth.
• Switches can function at one or more OSI layers, such as data connection, network, or transport. A multilayer switch is a device that operates at more than one of these layers at the same time.

You can also explore: What is Network Interface Card And Its Type

Advantages of a network switch 

Some of the advantages of a switch in networking are listed below:

• Connects directly to the workstation
• Helps with centralized management
• Aids in the reduction of frame collisions
• Increase the network’s available bandwidth
• Allows for numerous concurrent discussions
• Uses CAM table for a port to MAP mapping
• Reduces the workload on individual host PCs
• Supports VLANs, which aids in a logical segmentation

Disadvantages of a network switch 

Some of the disadvantages of a switch in networking are listed below:

• They are pretty expensive.
• Broadcast traffic could be an issue.
• Broadcast traffic can be problematic.
• The failure of a switching bridge brings the network to a halt.
• Switches in indiscriminate mode are helpless to security attacks.
• While they use a limited broadcast, they are not as effective as routers.
• Network availability issues are challenging to track through the organization’s switch.
• A network connectivity problem can be tough to track when we employ a switch.
• To handle multicast packets, proper architecture and, most importantly, configuration is required.

Conclusion

Switches connect devices in a network and use packet switching to send, receive, or forward data packets or data frames over the network. In this article, we have covered the basic functions and advantages of various network switches in order to determine which type of switch best fits your networking needs.