That does raise interesting security problems though - my car receives a message saying to stop as quickly as possible, how does it decide whether this is a valid message or someone hacking cars for fun?
The same way you determine whether that stop sign is legitimate or not: you don't. You stop regardless of the possibility that the sign was placed there by potential carjackers. Until the hacking risk is demonstrated to be statistically more dangerous than ignoring potential warnings, all warnings will be trusted. Regardless of current proposals, any manufacture that ignores reasonable electronic warnings (ie STOP accident ahead) on technicalities (ie an expired cert) risks serious liability.
This touches on the much more likely scenario whereby the car's internal data doesn't mesh with the data from it's sensors. If the sign says "one way" it is a one way street. What google maps says doesn't matter. Current warning signs trump previously recorded data. "But google maps said I could do 70!" will be no defense.
I don't have an answer for you, but maybe it stems from some sort of idea of identity? Maybe the car sends a message authenticated with your license ID. Cars are (hand waves) able to authenticate the validity of a message. If you send a message saying you were in a collision, that comes with the side effects of saying you were in a collision - emergency contacts and police may be notified, maybe something pings cars registered to you to see if it was actually in an accident based on sensor data. Your insurance rates may go up. If it turns out you were lying, maybe your car gets flagged for repairs next time you try to re-register your tags. Or maybe you are flagged for trolling and you get the "boy who cried wolf" effect.
Sure, the actual vehicle systems had better work and be properly authenticated, and that could be achieved in numerous ways... but none of this stops a hacker war-driving with a laptop, or sitting on an overhead bridge, or on the other side of the world.
There is no doubt that intelligent highways would be a massive target for terrorist and cyber attacks. However, one thing in our favour is the fact there is so little technology already in place, since they won't be burdened with decades' worth of insecure legacy systems: at least they'll be able to start out building infrastructure in full knowledge that it better be secure.
In some ways we have methods to mitigate this already in place. They have, of course, been exposed as insecure when they were implemented badly[1][2]. That being said, there is prior art on this, in nature.
You have your own trusted sources of information, and you have your secondary sources of information, which you apply trust levels to. Your own trusted sources of information are your own senses, your sight, hearing, feeling (touch), smell, etc. You may have something communicated to you about your condition or environment through these senses, but it's silly to take that at face value without confirming with your own senses. If your friend next to you that you trust tells you that you're about to walk into a wall, you look ahead. If you can't see a wall, you might slow and exercise caution until you figure out why you were relayed that information, but unless you can completely stop without problem, you don't do that without cause.
I think it's a mistake to think of cards in the future communicating as a swarm. They need to be able to function independently, and also to take in extra information from the group when the group is available, and make decisions on that. That's less swarm behavior than social behavior, so we should consider groups of cars on the road a social groups, and the same information dynamics exhibited in those groups apply.
Exactly, and it is not just this one case: serious, avoidable security cock-ups have happened every time a new class of device has been put on the internet, with the IoT DDOS debacle being perhaps the latest example.
Sadly, the lessons learned in legacy systems do not necessarily address the problems we have now. Older systems were typically combating noise, signal degradation, power consumption, processor speeds, poor user interface technology, etc. Often they were extremely proprietary and if they included any kind of security it was commonly by obscurity, and even if not, the crypto used would be easily crackable by a modern script kiddie packing Aircrack or similar.
The lesson we do need to learn is future-proofing: whatever infrastructure we install on the millions of miles of public highway will need to be serviceable for decades.
So, a malicious actor could spoof the vehicle of somebody they dislike, and cause their insurance to go up, or pave the path for a later incident, where when police/emergency are contacted, the person is ignored?
Couldn't this be solved better by some form of web of trust (WoT)?
Say your car A trusts other cars B, C ... Y to varying degree in a WoT. It meets a brand new car Z that is not yet trusted by any cars A-Y. Car A receives a message from Z, to which it assigns 0 credence points, meaning this data is not taken into account in any decisions. If car A then makes an observation confirming the message, car A now trusts Z by +1 point, and lets other cars know this. (I'm unsure how to make aggregation/distribution of trust work smoothly, but I believe the random mixing of traffic patterns will work in the system's favor.)
So gradually car Z becomes trusted, up to some maximum, e.g. 100. The only worry then is a malicious actor who mostly sends true messages, but that's hard to distinguish from a car with a sometimes faulty sensor. Those problems could be handled the same way, namely aggressively penalising a car for sending incorrect data (e.g. by -30), such that it's quickly distrusted, together with a prominent warning in the failing car when it goes below 0 trust that it needs maintenance (after which trust would be reset to 0). Possibly also increased insurance premium if your car remains with a trust below 0.
As always Science Fiction swoops in - in the "Culture" series, AI have hardcoded (as in, on their physical hardware) automatic code to shut down external communication in the event external communication is attempting to takeover the AI. I mean your question is pretty much "what would that automatic code look like," and I have no idea. I'm just getting pretty excited about all this sweet stuff happening with AI, automatic cars, hijacking of the human nervous system. Hngg.
> AI have hardcoded (as in, on their physical hardware) automatic code to shut down external communication in the event external communication is attempting to takeover the AI
This sounds very much like you're describing an antivirus program, which we all know works perfectly well /s
I agree, that is probably going to be one of the most difficult problems to solve. However, as we dive headlong into self-driving tech, we are going to have to find an answer since the tech will be so much easier to implement if the vehicles communicate.
