POWER This indicator lights green when the Switch is receiving power,otherwise, it is off.
Link/Act. These LED indicators are lighted up when there is a secureconnection (or link) to any ports. The LED indicators blink wheneverthere is reception or transmission (i.e. Activity--Act) of data occurring at aport.
100Mbps. These LED indicators are lighted up when there is a secure connection (or link) to 100Mbps Fast Ethernet device at any of the ports.