Prerequisite – Network Devices
A switch is a device which sends a data packet in a local network. What is advantage over hub? A hub floods the network with the packet and only destination system receives that packet while others just drop due to which the traffic increases a lot. To solve this problem switch came into the picture. A switch first learns, by flooding network just like hub to fill MAC- address table, on which port a particular device is connected. After learning it sends packets to that particular host only.
Layer 2 switch work on layer 2 of OSI model i.e. data link layer and sends a “Frames” to destination port using MAC address table which stores the mac address of a device associated with that port. Layer 3 switch work on layer 3 of OSI model i.e. network layer where it route packet by using IP address, it is used widely on VLANs.
| Layer 2 Switch | Layer 3 Switch |
|---|
| Operate on layer 2 (Data link) of OSI model. | Operate on layer 3 (Network Layer) of OSI model. |
| Send “frames” to destination on the basis of MAC address. | Route Packet with help of IP address |
| Work with MAC address only | Can perform functioning of both 2 layer and 3 layer switch |
| Used to reduce traffic on local network. | Mostly Used to implement VLAN (Virtual Local area network) |
| Quite fast as they do not look at the Layer 3 portion of the data packets. | Takes time to examine data packets before sending them to their destination |
| It has single broadcast domain | It has multiple broadcast domain. |
| Can communicate within a network only. | Can communicate within or outside network. |