Watch the design stream here: https://www.youtube.com/watch?v=kIY5orcxoxM&feature=youtu.be
In its basic incarnation this is for DC voltages, hence a DC input barrel jack that accepts your routers original PSU, and terminals for you to connect an appropriate plug to continue on into your router.
This is an untested design of a WIFI/IOT capable watchdog device. The idea is that it would be connected to your router and it would monitor the health of your network using latency measures / speed check etc and reset your hardware if it falls below a threshold or cannot get the internet at all! Can also operate on a timer.
This is an EAGLE CAD project