Dynamically-Learned MAC Address Feature

How Does the Dynamically-Learned MAC Address Feature Function?


How does the dynamically-learned MAC address feature function?



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A. B. C. D.


The dynamically-learned MAC address feature allows switches to learn the MAC addresses of devices that are connected to each port on the switch dynamically. When a device is connected to a port on the switch, the switch learns the MAC address of the device by monitoring the source MAC address of the incoming frames.

The switch maintains a table called the Content Addressable Memory (CAM) table, which stores the MAC addresses and their associated port numbers. As frames arrive at the switch, the switch checks the source MAC address of the frame against the entries in the CAM table. If the MAC address is not found in the CAM table, the switch adds the MAC address to the table and associates it with the port on which the frame was received.

If the CAM table is full, the switch will use a technique called MAC address aging to remove old entries from the table and make space for new entries. The aging time is the length of time that a MAC address remains in the CAM table before it is removed.

Option A is incorrect because the CAM table is not empty until ingress traffic arrives at each port. The CAM table is constantly updated as new MAC addresses are learned and old MAC addresses are aged out.

Option B is correct because switches dynamically learn the MAC addresses of each connecting device and store them in the CAM table.

Option C is incorrect because there is no maximum limit to the number of dynamically-learned MAC addresses that can be stored in the CAM table.

Option D is incorrect because the dynamically-learned MAC address feature does not require a minimum number of secure MAC addresses to be filled dynamically. However, switches may have features that allow for the restriction of MAC addresses to only those that are secure, such as MAC address filtering or port security.