- Each stp port is added sequentially so it was possible for our bridgeid to change every time because the new port has a lower MAC address. Instead just find the lowest MAC address from all Ethernet adapters in the machine as the value only needs to be unique, this stops a lot of churn on the protocol. - Update the states after enabling or disabling a port. - Keep tabs if we have been stopped or started by our parent bridge. - The callout only needs to be drained before destroying the mutex, move it to bstp_detach.