Hi,
If the link is not a point-to-point link, a temporary loop may occur during the P/A negotiation.
As shown in the following figure, SW1, SW2, SW3, and SW4 are in the forwarding state before the link between SW3 and the hub is connected. When the link between SW3 and the hub is disconnected, if SW3 and SW4 perform P/A negotiation first, a temporary loop will occur between SW1, SW2, and SW3.
