S2. How does a self-learning switch make its table?

Question 1

How does a self-learning switch make its table?

Answer 1

Dynamically, based on incoming traffic

Question 2

What happens when a frame arrives on the switch?

Answer 2

The switch examines the frame’s source MAC address and creates an entry in its table associating the address with the port the frame arrived on if the address is not already in the table.

The switch examines the frame’s destination MAC address and looks it up in its table. If there is no entry corresponding to the address, the switch will flood the frame on all ports except the one it arrived on to ensure it reaches its destination.

Question 3

What happens when a frame arrives at its destination?

Answer 3

The receiver will send a response frame, allowing the switch to create an entry in its table for the destination MAC address of the original frame if such an entry did not already exist

Question 4

How long does an entry remain in the switch’s table?

Answer 4

An entry has a finite lifetime, to ensure that the table stays up-to-date with changing network topology and doesn’t continue growing indefinitely

Question 5

When does an entry get removed from the switch’s table?

Answer 5

When no frames from the entry MAC address has arrived on the associated port for a certain amount of time (the entry’s lifetime)

Question 6

What are the benefits of self-learning switches?

Answer 6

Self-learning switches are efficient as they reduce admin workload and dynamically adjust to changing network environments.