1.1 LAN Switching
1.1.4 LAN switching overview

LAN switches are considered multiport bridges with smaller collision domains because of microsegmentation. Data is exchanged at high speeds by switching the packet to its destination.

Switches achieve this high-speed transfer by reading the destination layer 2 MAC address of the packet much like a bridge does.   The packet is sent to the port of the receiving station prior to the entire packet entering the switch. This leads to low latency levels and a high rate of speed for packet forwarding.

Ethernet switching increases the bandwidth available on a network. It does this by creating dedicated network segments (point to point connections) and connecting those segments in a virtual network within the switch. This virtual network circuit exists only when two nodes need to communicate. This is why it is called a virtual circuit - it exists only when needed and is established within the switch.

Even though the LAN switch creates dedicated, collision-free domains, all hosts connected to the switch are still in the same broadcast domain. Therefore all other nodes connected through the LAN switch will still see a broadcast from one node.

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