When a switch rapidly and continuously updates a MAC address in its MAC address table, what is this known as?

The phenomenon of rapidly and continuously updating a MAC address in a switch's MAC address table is referred to as MAC address flapping. This occurs when a switch detects that a MAC address is coming from different physical ports in a short amount of time. Normally, a MAC address should be associated with a single port where a device is connected. However, if a device is moving between ports or if there is a misconfiguration in the network, the switch can become confused, leading it to rapidly update the table with the new port information. This can result in routing issues and is indicative of network instability or topology changes.

In contrast, MAC address flooding involves overwhelming a switch by sending a large number of Ethernet frames with unknown destination MAC addresses, causing it to broadcast the frames out of all ports. Address resolution refers to the process of determining the MAC address that corresponds to an IP address, typically managed through protocols like ARP. Address saturation does not specifically refer to MAC address behavior in switches but generally refers to a state where a network device is overwhelmed by the amount or rate of incoming data and cannot process it effectively.