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Comment by skrebbel | Hacker News Reader

I just got an "NL Alert" about this, some kind of faux SMS sent straight to my phone. With a WhatsApp number, an alternative phone number, and a Twitter account. They seemed pretty well prepared. Emergency service via Twitter! Call me impressed if they can pull that off.

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They messed up. The WhatsApp number they included in the first NL-Alert is the phone number of the local newspaper De Telegraaf. It’s not owned by the emergency services.

They just sent a new NL-Alert with the right WhatsApp number.

The fact that they sent this specific number - the anonymous tip line of the largest Dutch newspaper - probably means that someone in the emergency taskforce team was actively leaking information to the press...

Cell broadcast is the technical term for the alert you've got

The third alert included the Whatsapp number and twitter address for the police.

There have been three alerts in the past hour. I'm hearing other people's loud phone alarms go off outside, several minutes after mine, so they weren't all sent out at the same time.

That happens for us frequently at the bi-annual test - somehow the iPhones always pick up the cell broadcast minutes before the androids do.

We figured it's just a priority order for the bomb shelters.

So in the end all that will be left of the human race will be Apple hipsters?

Wait, what? Priority order on a device or the station?

It is the same kind of format as the Amber Alert things I used to get in the states. How do they push that out? Based on location, cell tower usage, sim card?

Probably some form of cell, as me and my colleagues got them at the same time with different operators (different network operators, not virtual).

All of these kinds of alerts (amber, tornado, flood, fire, and presidential test) that I've received on the west coast of the USA have been based on very coarse regions e.g. entire cities, counties, or districts. Whether that is cell tower or not I can't tell, but I've always assumed it was.

It's like wifi broadcasts. It transmits to all devices in cell. It might do this for many cells and many operators/physical networks at the same time.

I didn't get them on my cellphone which was connected through the KPN mobile network, appearently there is some provider dependency here

Yes, access to the base stations in the network still goes through the provider and apparently that is the layer that has problems with interfacing to the outside world. Intra KPN traffic works just fine, including SMS.

You might not have it enabled? Do you have a recent Android/iOS device?

Each provider uses a different cell tower (or at least their own antennas on a shared mast), with their own independent radio frequencies.

"All devices in cell" is still accurate. Each cell belongs to a single provider.

It's up to the network backend to make sure all providers get the emergency message at the same time to forward.

> Each provider uses a different cell tower

This is incorrect. A lot of providers share infrastructure, there are even providers without infrastructure.

You are of course correct. But getting into the details behind MVNOs and roaming is a much more complicated topic than I'd want to type into a small comment box, and not really relevant to the issue at hand. :)

My point is just that CMAS-style cell broadcasts need to be repeated by each cell site, and cell sites aren't universally shared by all carriers.

It appears the problem here was at a higher level, the signalling fabric that transports the data for call setup, teardown, roaming and SMS, and to complicate matters even further apparently the 4G network is where the problem originated but it had effects far outside that. That's also why the whole thing appeared so patchy from outside.

Yes, amber alerts are one class of alert that uses WEA. It's based on the mobile station (phone's) location. The rules used to be written allowing per-tower granularity, but new FCC rules require 0.1 mile accuracy to whatever geo-bounding the author of the alert sets. The bounding can be specified as a circle, polgyon, or by geocode. Geocodes specify a state (or all), county (or all). Geocodes for EAS (the alert system on FM radio) allowed for county subdivisions drawn by the NWS. I don't actually know if those made it into WEA.

It's not as disruptive and open to abuse as an Orange Alert.

https://boingboing.net/2018/10/03/orange-alert.html

The alerts didn't come through on the KPN, affiliate and Vodafone mobile networks. I thought the Cell broadcast was independent of provider

It is and it isn't. The provider is still in the loop for the signalling portion and that happens to be the part that does not work. So likely all these alerts will appear after the problem has been solved.

I've gotten all three on Vodafone NL, but I'm roaming -- my home carrier is Verizon US.

Those only reached a relatively small fraction of all subscribers.

You should have gotten those NL Alerts every 6 months (well, if you're in NL) at the same time they test the "air raid" alarms.

The next test should be on December 2nd, although it feels to me like it's been tested enough today..

They test the air raid alarms the first Monday of every month.

I have never gotten an alert on my phone ever.

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