The LED model to use for setting the colors of the
LEDs on each port.  LAN models typically blink the
LEDs when data is transmitted or received on the port.
WAN models typically keep the LEDs green unless an
error condition exists on the port.

With SONET netmods the LED models use the following
algorithms:

LAN (3 states):

        if (LOS || LOF || AIS_L || LOP_P ||
            UNEQ_P || PLM_P || LCD) {
                rxLED = RED
        }
        else if (RDI_L) {
                rxLED = YELLOW
        }
        else {
                rxLED = AUTO
        }
        txLED = AUTO

WAN (3 states):

        if (LOS || LOF || AIS_L || LOP_P ||
            UNEQ_P || PLM_P || LCD) {
                rxLED = RED
        }
        else if (RDI_L) {
                rxLED = YELLOW
        }
        else {
                rxLED = GREEN
        }
        txLED = GREEN

With LAN and WAN models: RED means fault in receive
direction, YELLOW means fault in transmit direction
(RDI_L defect), AUTO/GREEN means no fault.  Only the
receive LED color is changed.  These models show only
three states and do not reflect the status of the
AIS_P and RDI_P defects.