Switches are network devices used to transfer packets within local area networks (LAN). A switch has multiple ports which enable multiple computers or network devices to exchange information through one central device.
How a Switch Works?
Switches develop their MAC address table by learning which devices connect on each port, associating their MAC addresses with that port, and learning which port their devices are on.
As soon as a switch receives a data frame, it checks its MAC address table to identify which port should receive it and sends the frame onward to that port.
If the switch cannot find its destination address in its MAC address table, it either broadcasts (broadcast) or floods the data frame out to all ports (flood).
Recall these key terms about how switches function: MAC address learning, data frame forwarding, broadcasting and flooding.
Functions of a Switch
Within a Local Area Network (LAN), switches are used to connect computers or network devices for internal communication and resource sharing, amongst their members.
Filtering data frames: A switch can filter data frames according to their MAC addresses table and only send them out to devices targeted in order to increase network efficiency and maximize network effectiveness.
Data Frame Forwarding: The switch provides fast data frame forwarding capabilities to facilitate fast LAN data transmission.
Virtual LAN (VLAN): Some advanced switches offer VLAN functionality to divide a LAN into multiple logical segments for improved network security and management flexibility.
Types of Switches
Unmanaged Switches: These unmanaged switches, also referred to as U switches, are frequently found in home or small office networks with easy configuration and management interfaces.
Managed Switches: (commonly referred to as Smart Switches) offer additional management features like VLANs, QoS levels and port mirroring that make them suitable for small to medium sized business networks.
Industrial Switches, also referred to as enterprise switches, deliver superior performance and reliability to support large network deployments and complex management requirements.