In this article, we will discuss What is switch in networking? How does it work? What are the advantages of switch? and the difference between Hub and Switch. So let’s discuss.
Switch in Networking
Switch is a network device that has multiple ports, used to connect computer devices and create a network. It works on layer 2 (data-link layer) of the OSI model and has multiple switching ports, whichever PC connects to its ports connects that computer to the network.
A switch can actually learn the physical addresses of the devices that are connected to it, store these physical addresses (called MAC addresses) in its table.
It’s an intelligent device because it has a memory where it maintains a table called CAM table (Content Accessible Memory), and stores the port number and MAC addresses of all devices, which helps to identify every device on a network.
Why switch is a layer-2 device?
Switch is called a Layer-2 device because it forward frames based on MAC addresses. It has storage capability, where a table is maintained. That’s table helps to identify every device connected to the switch on the basis of MAC addresses.
Let’s there are 4 PCs (pc1, pc2, pc3, pc4). When pc1 transmits data to pc2, data first arrives in switch device, where the switch knows which device is connected to which port, the switch looks at its table of MAC addresses and matching ports, and transmit the data to the correct port so the data packet would only go to that computer.
How does Switch Device work?
It works on star topology because all the devices are connected to the central node. Data from the source device is first arrived at the switch and then transferred to the destination device.
When first-time devices are connected to the switch, it broadcast the message, where it identifies the port number and MAC address and store it on its table, this information helps to identify the destination device on the network and sends it directly to that device.
So after the broadcast, the switch knows which device is connected to which port no, so next time it does not need to broadcast the message, it will forward the information with the help of port no and MAC addresses.
Advantages of Switch Device
- Multiple computers can connect using the switch and communicate with each other.
- It is an intelligent device because it can learn other devices’ MAC addresses.
- It maintains a table, helps to identify every computer on a network.
- Switch is able to work on full-duplex mode means each computer is able to send and receive data at the same time.
- There is no or very less frame collision because every port of the switch has a separate collision domain.
- It increases the performance of the network.
Difference Between Hub and Switch | Hub Vs Switch
|It is used to create a network.||It is used to create a network.|
|It always broadcast the data to every device.||First time it broadcast to identify every device on a network, then unicast the data.|
|Hub is not an intelligent device.||Switch is an intelligent device.|
|It works on layer-1 (physical layer) of the OSI model.||It works on layer-2 (data-link layer) of the OSI model.|
|It does not have any memory to store devices information||It has the capability to store devices information.|
|It does not maintain any kind of table.||It maintain a table where all device information is stored.|
|It cannot store MAC address.||It can store all device's MAC addresses and port numbers.|
|It operates on half-duplex mode.||It operates on full-duplex mode.|
|It has single collision domain.||Every port has separate collision domain.|
|Only one device communicate at a time.||Two or more devices can communicate at a time.|
Video Explanation of Switch Device
Frequently Asked Questions about Switch
What is the main difference between switch and router?
The main use of a switch device is used to create a network. Using a router we also can create a network, but the main use of the router device is to connect two (or multiple) different networks. Switch use the MAC addresses for sending data and router use the IP addresses for sending data.
How switch transfer the data?
Whenever a device sends data, then data first goes to the switch device where it checks in its table, this table stores MAC addresses and port no of all devices. So using this table, the switch knows which device connects to which port. So the switching table helps the switch device use the MAC address to send data to its destination device.
Is switch an intelligent device?
Yes, it is an intelligent device, because it sends data intelligently using the device’s MAC address.
Is the switch a data-link layer device or a network layer device?
Switch is a data-link layer (layer-2) device because it works on the basis of MAC addresses. It transmits the data to other computers using the MAC address in its table. The Data-link layer (layer-2) works on MAC addresses, so that is why the switch is a layer-2 device.
Why switch to using MAC address for sending data?
For sending data on the network, every device should have a MAC address (contains in NIC), which helps to identify that device on the network, and without MAC information you cannot identify any device on the network. Switch uses MAC information to identify every device on a network.
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