Why is my new residential fiber gateway box so heavy and so hot?

Question

My ISP recently upgraded my home to fiber (from DSL copper) and provided for the connection a Nokia BGW320 Wireless Integrated ONT Residential Gateway. They took away the old DSL gateway box I had previously had for ten years.I soon noticed that the new unit, while physically a tiny bit smaller than the prior unit, weighed 2 kg (4.5 lbs), which seems really heavy to me. And there is a sticker on it with the warning "Hot metal surfaces".What is going on here? Does it have something to do with the power of the wifi service (which I don't use). I can't help but think of some kind of electromagnet...

PaulHoule · Accepted Answer

I know some passive optical devices depend on precisely spaced gratings which would shift their wavelengths if the temperature changed because of thermal expansion. The easiest way to control the temperature is to keep them in an oven with a temperature somewhat above ambient. I don&rsquo;t know about customer premises equipment but I see ovens next to telephone poles all the time to maintain the temperature of optical hardware.

rektide · Answer

I've only seen a couple installs but a couple if the units have had builtin battery backup- a medium sized dense lead-acid.