5d ago

Power Loss but Still Online with Fiber Connection

Interesting experience, this has happened twice now. When house looses power I am still online now that I have moved to Fiber.

It feels a bit eerie. My network and computers, TV, media center, etc are all on UPS so they just keep going. Things just get really quite which is interrupted by just the periodic beeps of the UPS systems.

Does anyone know why my new Fiber connection does this but my old system which was bonded DSL did not? I know back in the early days of DSL I could do this, but some where along the way it stopped being power outage resistant.

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Most of the last mile fiber network is passive (doesn't require active electronics to pass the signal like DOCSIS/cable internet or ADSL).
Cable and DSL typically have the equivalent of UPSs in their neighborhood nodes, but they often go unmaintained.

Same experience here. The fiber usually is served from a point farther away from your house than with copper, and doesn’t need a powered repeater somewhere near your house. So if the neighborhood looses power, the last active fiber repeater before your connection might be far enough away to not be affected by the outage.

Your ISP has working battery backups. Don't expect it to stay on for longer, widespread outages though. When the power is out for a week, satellite is usually the only thing that will still work.
ISPs that still provide DSL, really don't want to put any effort into maintaining their equipment these days. They probably stopped replacing the batteries a long time ago.

Welcome to the secret internet when all your neighbors stop hogging it! (Well, less of a thing these days)
I was an early adopter of a cable modem with AT&T before download bandwidth caps. When the neighborhood went dark, I jumped to my computer and beeping UPS to download everything I could to find my max speed.

Your fiber ONT box (where the fiber signal gets converted to copper ethernet) probably has a backup battery in it. This is especially useful if you have VOIP landline phone service through your fiber provider so you can call for help if necessary when the power is out. You or your provider will need to replace this battery every few years, just like with a UPS.
- In my case the NID is in the basement and connected to my own UPS that powers everything on my main comm panel.

I've smelled the diesel fumes and heard the backup generators near my city's old telephone/internet central during a city blackout a bit over a decade ago, so at least those stay on during blackouts, but you'd think that various boxes along the way to the central might need power, right?
- Gigabit Passive Optical Network (GPON)
  Between you, the Optinal Network Terminal (ONT)
  and the central, Optical Network Line (ONL) there is only glass, fibers and prisms.
  It's all like an old school ethernet hub, or "thin ethernet" coaxial.

Does anyone know why my new Fiber connection does this but my old system which was bonded DSL did not? I know back in the early days of DSL I could do this, but some where along the way it stopped being power outage resistant.
DSL is just as capable of this as fiber optic. As long as both ends of the connection have power, your comms are fine, as you noticed in the early days.
My guess is that your more recent DSL service relied on a loop extender located near enough to your home that it was affected by local power outages.

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