Your Hub
Your Hub (modem) normally has just one light on, but from time to time you may see others turn on too. Here's a breakdown of what each one means:
WiFi LED
This should flash when the Hub powers-up, it then stays green for a couple minutes before turning off completely.
It may also flash green when the WPS button is used.
Internet LED
This should flash when the Hub powers-up, it then stays green for a couple minutes before tuning off completely.
It may also flash green when the Hub is performing a software update.
Phone LED
This should flash when the Hub powers-up, it then stays green for a couple minutes before turning off entirely. It may turn on if there's a phone network issue.
WPS Button (WiFi Protected Set Up)
This can be used in conjunction with WPS enabled wireless devices to connect to your home network.
Base LED
This should flash when the Hub powers up, then stays lit during normal use.