D-Link DCM-200 Quick Install Manual page 4

Verifying The Modem Status Lights
Power
Indicator
Verify the Cable Modem connections using the LED indicators
Power: On after the modem has been plugged into an AC power
source.
Link: On when the connection to the cable network is established.
The link light must be on before any physical connections are
made to the computer.
Act (Activity): Indicates that traffic activity is passing through your
cable modem port.
Status: On when the Ethernet cable is properly connected to your PC.
Link Activity
Light Light
4
Status
Indicator