Have no idea about how to monitor the temperature of the router.

No, there isn't.

Only an external device with a thermometer.

Ok. Thanks for the replies friends :-)

I hope the unit is kept in a well ventilated spot. I know this sounds v obvious but I have friends who tend to keep the unit hidden in their computer trolley/cabinet as they did with the wired modem, hence the suggestion. :)

I am keeping my router on top of a USB fan to keep it cool. Temperatire of 8968 is not increasing at all. :p

I too have a mini USB fan powered by the USB port of the router itself neatly hiding beneath the router itself

Secondly, opening up the router, i noticed the stock heat sink was stuck to the CPU using a blob of glue with no physical contact between the heatsink and the CPU chip (very shoddy workmanship) also the quality of heat sink itself was very poor. I ordered replacement heatsink from AliExpress with 3M thermal pads, set of 3 costed 60 Rs.

Placed one on the CPU, second on the Network controller chip and the third on the memory chip

Router has rarely hanged ever since :)