A switch in a computer network is a hardware device that acts a gateway between different networks or segments of a single network. A switch is responsible for receiving, processing, and forwarding data packets within a single network. On a single network, switches are fundamentally used to build up the network infrastructure, provide a more efficient data transmission route, prevent network loops, and often design a hierarchical topology to increase network throughput. In this article, we will discuss the basics of switches in computer networks, including their main functions, types of switches, and basic connections.

What is a Switch in Computer Network?

In a computer network, switches are networking devices that connect various components of a network. The switch translates and transmits data packets between nodes or segments of a single network. Commonly known as “bridging devices,” switches use MAC addresses (Media Access Control) to forward data packet from one part to the other. Switches are also used in networks to divide it into multiple segments, so that data packets can travel between multiple devices on the same network.

The term “switching” in context refers to the process of using advanced logic and algorithms to direct and transfer data between different nodes or systems on a network. Switches are used in both local area networks (LANs) and wide area networks (WANs).

Main Function

Firstly, a network switch is responsible for receiving, processing, and forwarding data packets to the designated recipient(s). For example, if a client wants to communicate with a particular server, a switch will process the request and find the pathway on the network and direct the packet to the requested server.

Secondly, switches can segment a single network into multiple segments. For example, if a network is made of two or more sub-networks, a switch can be used to segment the network by using VLANs (virtual local area networks). This process helps in routing the data packets within the network and makes sure that data packets are only allowed to go between authorized sub-networks.

Thirdly, switches can be utilized to block unauthorized access to a network. Switches can use a number of security measures such as MAC address filtering, port authentication, and access control lists (ACLs) to ensure only authorized users can gain access to the network.

Fourthly, switches can be used to create a hierarchical network. This network topology can help increase network throughput and ensure efficient data transmission. Switches can also increase redundancy in a network by providing multiple pathways between systems on the network.

Types of Switches

There are a number of different types of switches that are employed in computer network systems. The two main categories of switches are hardware switches and software switches.

Hardware Switches

Hardware switches are physical devices that connect various devices on a network. These switches can provide a variety of functions for a network, depending on its application and the hardware.

Unmanaged switches are basic networking devices that can be used in home networking applications. These switches are pre-configured and provide basic network functions such as packet forwarding and routing.

Managed switches are hardware switches that can be managed and configured with multiple features such as virtual local area networks (VLANs), Quality of Service (QoS), access control lists (ACLs), and more. Managed switches are designed for more demanding applications such as a large campus network or corporate network.

Modular switches are switches that are composed of multiple parts or modules that can be replaced or upgraded to suit the network’s needs. This makes it easy to add specific functions to the switch.

Software Switches

Software switches are virtual devices that are based on a software program or an operating system’s programming language. These switches run on a computer's host motherboard and can be used for certain applications such as load balancing or firewalls.

Basic Connection

Switches act as the gateways between two different parts of a network. To properly utilize a switch, a number of different connective elements need to be understood. The following are the basic connections made when using a switch:

The most common connection for a switch is a directly connected port. Here, the switch is connected directly to a device on the network. This connection is the simplest type of connection and requires minimal setup.

The second type of connection for a switch is a trunk connection. Trunks are used to connect a switch to another switch or to other networking components. In a trunk connection, multiple lines of data are sent at once, unlike with a direct connection.

The third type of connection is an EtherChannel. This is an aggregation of multiple ports on a single switch. It is a more advanced connection used to increase bandwidth and throughput on a network.

Finally, the fourth type of connection for a switch is a stacked connection. This stacking connection is used to connect multiple switches together to form a virtual switch. This connection is ideal for larger networks where a single switch is unable to handle the amount of traffic on the network.

Switches are an integral part of a computer network. They are responsible for receiving, processing, and forwarding data packets within a network, as well as segmenting the network into multiple sections. Switches are available in either hardware or software form and can be used for different applications such as load balancing or firewalls. Knowing the basics of switches in a computer network is important to building a robust and efficient network infrastructure.