Network Switches:Understanding the Differences Between 10G, 1G, L2, and L3 Devices for Improved Network Performance

Our previous session in this Beginner’s Networking Training Series gave us a thorough introduction to subnetting and network classes.

At layers 2 and 3 of the OSI reference model, switches have a variety of functions and applications that we will learn about.

Here, we’ll examine the key distinctions between layer-2 and layer-3 switches‘ operational principles.

The fundamental idea that distinguishes how both types of switches operate is that layer-2 switches direct data packets to designated switch ports based on the MAC address of the destination host.

These kinds of switches don’t use a routing algorithm. In contrast, Layer-3 Switches use a routing algorithm and base the target host’s IP address on the next defined hop for data packets that are destined for that host.

Layer-2 Interrupts

We have an intriguing question that comes to mind after reading the introduction to both layer switches above. How would switches at layer-2 learn the MAC address (a machine’s unique address, such as 3C-95-09-9C-21-G2) of the following hop if they don’t use a routing table?

The Address Resolution Protocol, also known as ARP, will be used, is the answer.

The way that this protocol operates is as follows:

We’ve used the network example, where PC1, PC2, PC3, and PC4 are the four host computers that are linked to the switch. Currently, PC1 is attempting to send PC2 a data packet for the first time.

While PC1 and PC2 are just starting to communicate, PC1 is aware of PC2’s IP address but is unaware of the host’s MAC (hardware) address. Therefore, PC1 uses an ARP to learn PC2’s MAC address.

The port PC1 is attached to is not included in the list of ports to which the switch sends the ARP request.

PC2 will respond with an ARP response message with its MAC address after receiving the ARP request. Additionally, PC2 collects PC1’s MAC address.

The Switch is able to determine which MAC addresses are assigned to which ports as a result of the message flow described above. The switch now collects PC2’s MAC address and stores it in its MAC address table as PC2 delivers its MAC address in the ARP response message.

Additionally, it saves PC1’s MAC address from the ARP request message that was transmitted by PC1 to the switch in the Address table. From this point forward, the switch will simply look up the data in its table and transmit it to the destination port of PC2 anytime PC1 wants to communicate anything to PC2.

In this manner, the Switch will continue to maintain each connecting host’s hardware address.

Broadcast and Collision Domain

When two or more hosts attempt to communicate at the same time over the same network link during Layer-2 switching, collision might happen.

As the data frames clash and must be resent, the network efficiency will suffer in this situation. But typically, every port in a switch is located in a different collision domain. Broadcast domain refers to the domain used to forward all types of broadcast communications.

Switches are not excluded from the list of layer-2 devices that occur in the same broadcast domain.

Conclusion 

In conclusion, network equipment is a critical component for modern day networking systems. Network switches, in particular, play a crucial role in forwarding data packets to their intended destinations. There are different types of network switches available, including 10g switch,1g switch,L2 switch,and L3 switch. Each type of switch offers unique features and functionalities, catering to the specific requirements of various organizations and businesses. The choice of the right network switch depends on the specific needs of the organization, including the size, number of users, and types of applications that need to be supported. To ensure that a network runs smoothly and efficiently, it is important to make an informed decision while choosing network equipment, including network switches.