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Comment by numpad0 | Hacker News Reader

You don't need a full concert hall to test 911, the simplest LTE test equipment can be just couple sandwiches big. They're also not expensive at Google scale. It does concern me that there were anecdotal posts that read to me like that, developing firmwares and not blatantly violating basic assumptions and principles and core premises of Google MDM cannot occur simultaneously. If I somehow had to, I would bet that that to be on the path to the root cause. I mean, a lot of software jockeys have to be explained that IP address isn't assigned to a CPU socket.

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You need a special room as well - you can't accept that someone near your building might end up having his 911 call routed through your test infrastructure.

Alternatively, I think you can somehow connect the device antenna to your equipment, so that the signal doesn't even have to be transmitted over the air (or at the scale of a femtocell). Still, rather "expensive" to setup in multiple locations for just a team that develops a dialer.

Additionally, you'd have to test this across multiple OS versions, and devices. Still doable, but most likely not incentivized by the managers at Google

I don't see why it would be expensive, for no other than Google, to set up a microwave oven with a factory rooted phone and a femtocell inside on ~dozen locations worldwide. There's no special legal or financial complexities in doing that.

And selling phones that can't pass certification is just irresponsible. If you can't make a product work, you're free to be responsible and cancel a product. It's on Google to do businesses legally.

The faraday cage in a microwave is good for its purpose, but not good enough at blocking cell phone bands. They would need something slightly more expensive, anywhere from $1000 to $50k depending on how fancy they wanted to be. Of course Google should have no problem affording any of that, but these details do matter.

I suspect that the problem must be more complex than a bug in just the phone or the OS; for one thing, the problem is intermittent and doesn’t affect every phone. Still, the lack of action from the FCC is disturbing.

Can't you stand up your own test network for that? Other phones won't connect to that, so you don't need to fully rf isolate, as long as you have some trust in the test network not doing crazy things. It's well over a decade ago, in Europe, and I was only very peripherally involved, but it didn't seem that hard to get permits for such a test network indoors.

I think the problem is, 911/112 calls are routed through the best cell network available. This means that if somebody is close enough to your lab, their phone would still try to use your femtocell.

From very dim memory: I think there's some flag you can set that marks your test network as not suitable for that kind of thing. But even if not, IIRC you can set routing information for stuff like 911 on a subscriber basis in your test network - which you'd just do for the handset you're testing.

In that case, you'd just be changing yet another variable and not test the emergency mode of the modem - which might actually be broken due to a software update, right?

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