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Comment by gumby | Hacker News Reader

The biggest problems is power. The phone company power the POTS line — you can even make an emergency call from an abandoned building with no electrical service (and no phone subscription) if you find a jack and plug in. Under those huge central office buildings are huge banks of -48 V batteries which are required to provide a week of power (or was it two in the US? I can’t remember).

Now you’ll have a router with a battery that the owner doesn’t know about and won’t service, so that within a year or so it won’t work. In an emergency: no phone service.

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This assumes that anyone has maintained the 48V infrastructure, which doesn’t seem like something that will be feasible considering the insignificant quantity of customers using true copper landline service.

The other problem with customers preferring not to have landlines is that by the time they need them, it’s too late to convince them to buy a traditional telephone and plug it in. You are likely to be nursing home age if you still prefer having a landline. You can have amazing infrastructure but if nobody uses it, it’s useless.

What we really have now is cellular sites with their own infrastructure aiming to keep them operational during power outages.

Then we’ve also got various satellite services that are growing in capabilities day by day, and are built in to common devices like iPhones as an SOS method.

I’m not in the UK but my house was built relatively recently and it doesn’t have any telephone jacks. The theoretical benefits of a landline are entirely theoretical. The ship has thoroughly sailed.

You put the battery in the RC and have a battery maintenance schedule. They do that today: the CO battery is just for phones within a few miles of the CO, so rural setups use distributed batteries. Ppl forget how much of California is quite remote and (to my pleasure) without mobile coverage.

I have copper service (buried) for the alarm system in my house in Palo Alto, powered by the CO. I will be sorry to lose it.

The cell ppl so have batteries in the bis and ter nodes but not long term power like the phone company has to do.

Satellite bandwidth is quite limited and uses a lot of power. It’s not really a solution, especially with consumer terminals. It’s just a handwave to get away with not dealing with the problems.

Overall this is a step backwards on safety. Telecoms MAHA

My amateur radio friends used to sound paranoid when they talked about how it might be the last form of communication in an emergency. After all, I'd seen how overbuilt and reliable the PSTN was.

Now I wonder if maybe it's time to get licensed.

In a true emergency, I don't know that it matters whether or not you're licensed.

I agree though that getting licensed might be useful for knowing how to use it.

> I agree though that getting licensed might be useful for knowing how to use it.

That's the whole point IMHO. You need practice to properly use a radio, especially during an emergency.

In an emergency, either actual emergency services will be using all of the bands and amateurs will be well-advised to shut up, or the military (official or bandit) will be and, again, amateurs will be well-advised to not make themselves targets. Some people get the odd ideas that the Big Ones will be more like Northridge in 1994 than Cambodia in 1970.

Why would emergency services fill up the amateur bands?

Keeping everyone else quiet to remove the possibility of interference is just good sense. The Baofeng people alone would be a huge, unnecessary distraction.

> You put the battery in the RC and have a battery maintenance schedule. They do that today: the CO battery is just for phones within a few miles of the CO, so rural setups use distributed batteries.

I don't know for sure about POTS, because the pricing was prohibitive, but my local telco certainly did not use batteries at the remote terminal to keep ADSL online... when utility power dropped, ADSL dropped instantly, even when the outages were under 10 seconds.

My local wireless telcos provide about 4-8 hours of wireless after utility power drops. Not great, but better than what I got from ADSL + voip.

My neighborhood (along with most of the city) was without power for a couple of weeks following the 2012 derecho. I had VDSL at that time.

The VRADs scattered around the city included a battery that worked for as long as it worked. But I never did discover how long those batteries would last, because AT&T brought portable generators out to supply power to their VRADs.

I kept my end alive with the portable generator that I was using intermittently for everything else along with the backup battery that the modem came with.

The VDSL circuit never dropped during those two weeks -- and yes, I read the logs afterward with some astonishment. :)

(Since the RF environment was extremely quiet, wifi had fantastic range. I opened up an SSID for anyone within earshot to use and some folks actually did use it.)

---

Fast forward a dozen or so years. When the power dips in my neighborhood, the cable network drops out with it. So, sure: I've got a small UPS for my little stack of network gear, but fat lot of good that does when there's nobody for it to talk to.

And I've got ways to use LTE/5G as a backup, but the performance of the cell network also nosedives at that same time. It's not clear to me if that's due to a service interruption or instead due to everyone's pocket supercomputer switching from wifi to cellular data, but whatever the cause: It turns pretty useless.

(I'm on FTTH fiber now but it's only been a week. We'll see how it does the next time there's a power issue.)

AT&T is using old people to market their new cellular-to-POTS bridge product.

The premise is she needs something as reliable as a landline, because during California wildfires the cell towers and power go down.

Maybe someone should have whispered to her that this product uses the same cell towers, or equally-vulnerable broadband. I could not stop laughing.

https://www.youtube.com/watch?v=Ud2LaFDEUho

This makes me think that the marketing at AT&T is outsourced to a group that has no idea how the service works.

From the user guide[1], it appears to be a dual-WAN setup that uses both cellular and broadband. Not as good as decent POTS, but better than just cellular or broadband.

https://www.att.com/scmsassets/support/other/att-phone-advan...

My understanding is it's wireless first, with failover to broadband. The broadband connection is optional.

They cannot manage the QoS over the broadband link.

My personal experience is any power outage lasting more than a few hours is also going to take out your community's broadband.

This is already partially the case with POTS where I'm at. My wife was attached to this reliability aspect of the overpriced POTS service we had. But when they installed fiber to the node some years back they placed batteries at the nodes which seem to die after a day in a power outage. When everything came out of a CO they could just run a diesel generator for about forever in comparison.

The bright side was this helped me convince her to get rid of the POTS as the benefit she wanted was larger already gone anyway.

> Now you’ll have a router with a battery that the owner doesn’t know about and won’t service

In Canada, Bell has actually discontinued battery backup in their latest modems, supposedly because they were having trouble with modems not rebooting correctly.

Verizon forces me if I want battery backup for my ONT to provide 12 D cell batteries.

https://www.verizon.com/support/residential/battery-backup/p...

What a fuckin' joke.

I think a solution to this is mandate providers provide a cellular interface for households for emergency response, with battery backup. Basically a mobile hotspot with a phone jack, speaker, microphone, and red button to call for help attached to a chonky batter pack. Device inventory and health is required to be reported to regulators.

This solves for power, and reporting means it’s trivial to log and audit if the devices are online and available for emergency service calls.

If a mobile tower isn’t available in the area, a tower must be made available for the sector coverage.

Anything else in a world of fiber to the home is compliance theater, as your example shows.

That doesnt help when a natural disaster cuts power to an area for more than 24 hours. Cell towers dont have multi day battery capacity and with everyone calling their loved ones in the effected area they will be even more congested than normal. So even if they do have power your still likely to lose signal when the towers get ddosed by everyone trying to use them at the exact same time.

You see the same thing happen when theres a mass shooting and you get tons of people calling 911 and then you get a ton of people calling their loved ones to find out if theyre okay.

The cell towers also rely on an internet backbone so if you lose power long enough to lose internet then you lose cell towers even if they have all the power they need.

You could try putting all the communications infrastructure on a high priority circuit or something but unless your going to build out a hardened power grid parallel to the existing one, that would only cover you from load shedding not from natural disasters or even just power lines sagging on a hot day until they short circuit and blow the grid. So im not sure it would be worth the cost.

There's some sense in which I prefer this, though, because at least I know how to source D batteries and they're a commonly available standard and I know exactly what their shelf life is. I might even have spares around in my emergency kit for things like lanterns and radios. I've also seen Verizon battery backup units that run on small lead-acid batteries which seem to need frequent replacing, and require me to look up the details and order from a specialty vendor every time... more annoying to keep extras of those on hand and tough luck if it reaches end of life shortly before or during an emergency.

> Verizon battery backup units that run on small lead-acid batteries which seem to need frequent replacing, and require me to look up the details and order from a specialty vendor every time..

Have you? All of them I've encountered take a very standard 12V lead-acid battery - the same one that's inside consumer UPS units - and you can get replacements from a dozen brands on Amazon and other vendors.

I probably have to replace them every 2-3 years, though I imagine alkaline D-Cells would be far worse.

In my experience, the bigger issue with Verizon's battery backups was that when the battery starts failing, the device beeps loudly every minute. That's especially problematic in apartments, as it tends to be within earshot of the bedroom. And the battery backup system is present in the ONT box even if you don't have phone service, or ever want it; and even if you own your home, it takes a lot of complaining to get Verizon to remove it. Horrendously stupid design.

> All of them I've encountered take a very standard 12V lead-acid battery - the same one that's inside consumer UPS units - and you can get replacements from a dozen brands on Amazon and other vendors.

There's about 70 different sizes for these standard 12V lead-acid batteries though. And most of my consumer UPS units hide the battery behind a security screw and don't list the battery size in the docs. If the battery was removed and not replaced, it's harder than it should be to find a new one.

You can get amazonbasics NiMH D-cell batteries for $24/4-pack.

Tricky bit is getting a good charger if you're getting them for a device that doesn't charge its own batteries.

And ignore the bold text saying not to use rechargeables?

I've been ignoring those for decades with no ill effects.

If you look at the voltage curves, Alkaline batteries start at higher voltage than NiMH but drop below NiMH voltage pretty quickly, so unless you have a device that stops working when your alkaline batteries drop below 50% charge or so at 1.2V, there's no reason to avoid NiMH.

It my not be a big deal for a completely solid state device but definitely pay attention to those notices for anything electromechanical, the issue isn’t the voltage but the current draw. And given that your broadband device is a transmitter, it could possibly matter at the margin…which for the topic under discussions could be precisely were you need it.

Can you elaborate on that? AFAIK the only real upside of the current draw properties of alkaline batteries are for very low draws where you'll get some additional runtime out of them. (e.g. I can swap the alkaline batteries in my tv remote every 5 years rather than charging the NiMH batteries every 2.5 years.)

If it cared about current draw would it still say not to use lithium D cells?

And I thought NiMH was better at current draw than alkaline.

How many people still have a corded phone, and how many of those would remember that those phones still work when there's no power?

It's much more important to ensure that the cell network is resilient. Backup power, mobile towers that can be deployed to disaster areas, and continuing the rollout of satellite connectivity will help far more people than maintaining landline infrastructure.

Not in the UK, but almost everyone I know has a landline in their house (although some may be VoIP). In a disaster scenario the cellular networks are going to be overloaded.

and landline won't? it's also oversubscribed. pretty sure it isn't guaranteed e2e circuit switched either, and that it hasn't been for quite a while.

In the US the POTS telcos have a strict availability requirement that constrains the oversubscriber ratio. It was these requirements that lead to the development of the erlang unit in queueing theory.

So don’t worry about that particular issue on the POTS side. On wireless, it feels like anything goes (not really true, but by comparison it’s the Wild West)

My grandparents - and I imagine many people of their generation would assume that if their power failed, they could still pick up the phone and dial someone to get help, as they always could in the past. Not to mention that, at least in the case of my family, they may have a mobile phone but that doesn't necessarily mean they can remember how to use it.

In case anyone was wondering, the -48V was chosen to reduce electrolytic corrosion and is the approximate voltage of a 24S lead acid battery. Later, PoE inherited this voltage standard.

The important part about corrosion protection is that the voltage is negative with respect to the ground. The absolute voltage is more for distance, and low enough to be safe. Nice read for those who are interested: https://pe2bz.philpem.me.uk/Comm/-%20Telephone/Info-901-Tele...

Supplying (very limited) power, data (full-duplex!), and signaling over a single twisted pair was certainly a concept far ahead of its time.

The system is so robust that for a long time in remote locations there was only one wire, with the return line simply being the top wire of a barbed-wire fence. Couple that with a party line and you could service a lot of remote customers for a very low cap ex.

No, the batteries typically do not last a week. More like ~8-ish hours. But there are typically also backup generators.

The impression I have is that the batteries are, in part, sized to give you a chance to fix the generator if it doesn't immediately start up.

Sorry, I was speaking about the US POTS. My apologies for not being clear, especially when commenting on a post from a UK site.

CO buildings in the US still maintain that infrastructure even though the buildings themselves are full of broadband hardware and an actual CO is now just a block of RAM

You wont have a battery. In the UK they stopped providing a battery backup when they switched to the newer ONT quite a while ago, and routers typically do not include one either.

There are a few generic router battery backup products on the market but none specifically get advertised as working on the ONT, but many do. Realistically though they're utterly pointless when you can pick up a vastly superior APC UPS for the same price.

My plan is to stick my UniFi gateway / switch on a UPS, and get one of those power over Ethernet injectors / barrel jack extractors(?) to power the OR ONT.

Chatting to the BT guy that last visited, they reckoned the street cab would only last for half a day or so without power.

Yeah for mine I've got the unifi cloud fibre gateway but currently use its sole poe port for a u7 lite. Thats on an APC UPS which will give me 3-4hrs life. Then for the ONT I've just picked up a relatively cheap Eaton UPS that should give it approximately 3-5hrs. TBH any outage longer than that and I'm out of the house for the day until its fixed!

> Now you’ll have a router with a battery

If you're lucky. Not sure if US or UK is enforcing batteries on routers to provide emergency services, but AFAIK in most of Europe there's nothing like that.

my new 2.5 Gb fios ont eliminated the battery, when power goes it goes as well

Would plugging the ONT into a UPS work?

Err yeah except actually you'll just pull out your mobile phone and use that.

Not possible for a lot of rural areas

Depending on how long and large the power cut is, the cell towers might eventually go offline and then you don't have any cellphone service. Happened here in Spain + Portugal recently: https://en.wikipedia.org/wiki/2025_Iberian_Peninsula_blackou...

A blackout that severe would surely affect POTS too.

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