Normally provided on optical network terminals (ONT), this red light indicates that the unit is not receiving a signal from your fiber internet provider's Passive Optical Network (PON). Here are a couple of quick and easy things to try if your modem, ONT, router, or gateway isn't. Whether your modem is blinking orange, your router has a solid red light, or you are staring at a mysterious "DS" indicator, you will find the answer below. Blinking green typically means data. A red light on your router can be a source of frustration and confusion. Fortunately, diagnosing and resolving these issues doesn't have to be complicated. However, when it blinks red or stays solid red, it signifies a Loss of Signal, a problem preventing your router from communicating. The tables in this article provide detailed information about the possible appearances of the LED lights on each device, the possible causes of each state, and what you should do.
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