In STP, the port states are as follows:

• Disabled: In this state, no frames are forwarded and no BPDUs are heard
• Blocking: In this state, no frames are forwarded but BPDUs are heard
• Listening: In this state, no frames are forwarded, but the port listens for frames
• Learning: In this state, no frames are forwarded but MAC addresses are learned by the switch
• Forwarding: In this state, frames are forwarded and MAC addresses are learned by the switch

The moment you connect a device to the LAN switch, the port goes through these stages, and the time it takes is as follows:

• From blocking to listening takes 20 seconds
• From listening to learning takes 15 seconds
• From learning to forwarding takes 15 seconds

In RSTP and MST, the port states are as follows:

• Discarding: In this state, frames are discarded
• Learning: In this frame, no frames are forwarded and MAC addresses are captured
• Forwarding: Frames are forwarded and MAC addresses are captured

The entire port state transition from discarding to forwarding should take a few seconds depending on the network topology and complexity.