D-Link DES-1316 Manual page 22

There is a light indicator behind the "View Trap" button. When the
light is green, it means that there is no trap transmitted, and when it is
red, it means that a new trap has been transmitted, reminding us to
view the trap. (Figure 7)
When the "View Trap" button is clicked, a Trap Information window
will pop up. It will display the trap information including the Symbol,
Time, Device IP, and the Event occurred. (Figure 8)
The symbol " " represents the trap signal, this symbol will disappear
after you review and click on the event record.
Figure 7.
Figure 8.
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