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Comment by jackfoxy | Hacker News Reader

Mechanical systems generally have well established failure modes, frequently related to parts wearing out with use. Often these failures can be predicted by warning signs or history of use.

Networked software systems generally have completely unknown and unpredictable failure modes.

Do you really want important infrastructure like your automobile dependent on networked software?

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The key card still works, as I would expect. The car isn't dependent upon network infrastructure; an optional convenience is dependent upon it. You can operate a Tesla fully without installing the Tesla app.

As a comparison, my last car was a BMW. For that car, I had key fobs. I always had to take one of these key fobs in order to unlock and use the car. So going out, I would have one key with which I could operate the car.

Now, because I always carry the key card in my wallet, and I always have my phone, I always have _two_ keys with me. This isn't worse than having only one key, even if one of the keys is failing today due to an internet outage.

Essentially, I'm experiencing the worst case scenario right now, which is that I'm exactly the same situation as when I had my BMW. It's annoying (and as an iOS dev, I Have Questions on how the app came to be architected such that a network outage erases the app's settings). But I'm not worse off

Is it standard practice to carry around the keycard? Most owners I know don't bother. So this could potentially strand them unexpectedly but I suppose that's the same for any other car if you lose your keys (but at least not losing your physical keys is in your control).

Yeah, they're credit card sized so I usually carry one in my wallet. Mostly to give to a valet if I need it. Some people have melted them down into fun key chain fogs. My gf has it as a ring.

I am a fan of a minimal wallet. I don't carry stuff I can do with my phone.

The card is a millimeter thick. It will fit in a minimalist wallet.

You can say that about 20 different cards individually and suddenly your minimal wallet isn't very minimal anymore

But since Tesla's app can spontaneously stop working, might be worth sucking it up and carrying the card anyway

For sure, IDK if my dad broke me, but I always try to have a backup for everything. Keys included.

Two is one and one is none!

Your dad fixed you and is smart.

Wait.. people melt the cards down into shapes? And they still work?

Yeah, you dissolve the plastic in a solution then take the antenna and form it into the shape you want.

I can't speak for every owner and I'm sure some don't, but I certainly carry my key card in my wallet 100% of the time. It just makes sense; what if your phone dies? You are already required to have your driver's license while driving, so it's not like you can avoid carrying cards around, and carrying one more card is not as much of a burden as a giant key fob.

I personally carry my key card at all times. It's the size of a credit card in my wallet so it's no bother. Regardless of how good their network services could be, I would never want to depend only on my cell phone to drive. You know, the thing I own that's most likely of all things to run out of battery, break, get stolen, be out of service range. All things that would strand me.

> as an iOS dev, I Have Questions on how the app came to be architected such that a network outage erases the app's settings

Never storing it in the first place. Too many apps I’ve worked on have been of the opinion that being on a phone means you always have internet access, so why not eliminate cache invalidation issues by just storing all of your data on a server instead of locally?

> Do you really want important infrastructure like your automobile dependent on networked software?

Is the automobile actually dependent on this infrastructure, or does that infra just provide some nice perks and extra features? If the car will still lock, unlock, drive, and refuel -- indefinitely -- without the network components, then I wouldn't consider it dependent on the network.

Of course, when adding extra features, we should strive to only make them dependent on the network if they truly require the network as a part of their basic premise. I suspect the Tesla has some extra features that could work fine without the network, but are probably broken because of this, and that's... not great.

Your idea is correct, the network access is optional. Everything works, it even has downloaded maps. You can't remotely unlock or lock via phone when the net is down. But your keyfob will just work. I checked just now and I can seemingly do everything at the moment with the app...

The regular NFC card still works fine.

When I took delivery of my car, the guy told me to just always keep the NFC card in my wallet. Honestly I thought it was more likely that I would have a dead phone than Tesla would have a network outage, particularly one lasting multiple hours, but I guess my phone charging is more reliable than their network configs. Given how unreliable and flaky I am, it's pretty damning of Tesla's technical chops.

> Networked software systems generally have completely unknown and unpredictable failure modes.

"A distributed system is one in which the failure of a computer you didn't even know existed can render your own computer unusable." -- Leslie Lamport, 1987 (https://lamport.azurewebsites.net/pubs/distributed-system.tx...)

The problem is even more complex. For most people it is just the app right now. But what people do not realize is, that the devices networked in the car itself are trusting each other by some means of certificates. These certificates needs to be renewed regualry. If there servers are becoming unavailable for a longer time while the certificates expire, the connected device will not trust each other and will refuse to work.

Can you cite any specific parts that are handshaking via certificates that need renewal? In many cases device authentication is turning towards certificates that don't expire, and I'm unaware of any certificate renewal cases inside a Tesla. If they are there, I'd love to know about them.

I suppose you wouldn't be able to update the os. But the car is just fine without network access. You can unlock with key, charge it, etc. It doesn't require network connections in any way. It has downloaded maps. Unlike say your BMW, your car maps get updated periodically over the internet.

Your power grid runs on networked software. The key is redundancy.

Though the timing may be unpredictable the failure mode seems clear.

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