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Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

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Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#201

Post by Spivak »

sebmellen wrote: post #181
rebelos wrote: post #136

Earlier quoted context omitted.

I would just like to say that if anyone has a rational counterargument to this, I really want to hear it. This is precisely the observation past which the logic becomes less coherent in just about any conversation I've had on blockchain applications.

Please see my comment in response to the grandparent comment. I think it will address your concerns with a rational counterargument. Basically, yes, you could, in theory, maybe, sort of, possibly, build a similar system without a public blockchain. But why? I'm sure there are people who can build houses with a few hand tools, but there's a reason we have power tools and heavy machinery — they are more efficient and f…

I think the thing that you have to answer is why you need distributed consensus. You're a startup with a business relationship with your customers -- you're the common trusted party. Your customers are using your software so if they were worried about you cheating the system they (and you) have bigger problems since your business is reputation.

Also what is the point of mining or and proof of $whatever system? The thing your customers provide is a signed attestation of some fact and you provide a signed attestation of the time that fact was received. Why is there a need to "vote" in way on what is true? This is just a database or honestly a folder of signed messages.

And I say signed, but none of this really need to be cryptographic in any way since they're customers that could just authenticate to you which is as much a proof of their identity as any key.

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#202

Post by johnisgood »

geofft wrote: post #108
johnisgood wrote: post #81

Earlier quoted context omitted.

Only that? What about non-editable history?

You can do that with a plain old hash chain without any mining of blocks. Certificate Transparency does this - each monitor adds records to their ledger and signs them, and the latest record includes a hash of all previous records (via a Merkle tree). Auditors trust any hash they see which is signed by a monitor. If they see two ledgers where one is not a subset of the other, they trust all the data in both ledgers.…

Yes, but he said that it only solves a singular problem, and did not mention this property of the blockchain. Blockchain provides this, does it not?

I have been looking around https://github.com/google/trillian, looks interesting.

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#203

Post by doonesbury »

sebmellen wrote: post #177
snarf21 wrote: post #106

Earlier quoted context omitted.

Sorry, but your solution solves nothing. The transporter could take a picture of the odometer and tweak the image. Your solution is only as secure as the input flow and you can't control it. A blockchain can't reflect physical reality. It can only reflect what someone said/says physical reality is. Additionally, they have to trust you to push the "right" data to the blockchain. If they are already trusting you, you c…

No need to be so snarky. Could someone tweak the image? Of course. But as a practical concern, probably less than 20 people have the image manipulation skill it would take to do something like this in the ~20 minute handoff period. The transporters certainly don't. This is a bullshit argument, and you know it. And these pictures are not just of the odometer, but the entire car, including the VIN. Photoshopping all of…

I agree with the question: is anything really be solved here? No, not really. A db table of jpegs taken at different points in the hand off is essentially fine too. Carfax seems to so fine without blockchain. And really the bottom line is the end recipient: what recourse is there if the car shows up with too many miles?

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#204

Post by doonesbury »

_asummers wrote: post #163
ummonk wrote: post #75

Earlier quoted context omitted.

To make sure I understand it correctly, the blockchain is acting as a distributed notary service, right? That definitely feels useful.

The power of a notary is that someone is legally verifying the state of the document under penalty of perjury. In this case, you don't trust the party doing the verification, by definition, and there's no second party, so I don't see what this solves. That there is an immutable log of the events is an implementation detail and could be solved with a write only DB completely independent of blockchain.

Agree. There are consequences if the notary lies. If bad data is posted to the blockchain ... Well ... So what? That's why I asked the original poster of scenario what the end receiver's recourse is if he gets a car with too many miles? Arguing about blockchain and what it did or was supposed to do will be immaterial by then.

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#205

Post by saati »

thekevan wrote: post #162
rebelos wrote: post #136

Earlier quoted context omitted.

I would just like to say that if anyone has a rational counterargument to this, I really want to hear it. This is precisely the observation past which the logic becomes less coherent in just about any conversation I've had on blockchain applications.

Well in this specific example, what would they change to photo to? The case is to stop joyrides. Who would be able to take a joyride and end up with the odometer exactly as they had Photoshopped it to hours or days ago? But yes, depending on the application, photos can be manipulated. But that is stating the problem with using photos, not the timestamping app.

It would be cool to have technology that tells you how long is a trip, oh wait, precise maps are hundreds of years old.

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#207

Post by setr »

sebmellen wrote: post #7

The biggest use case I have found of blockchain tech is timestamping, especially in a case where the timestamping party cannot be trusted to act honestly because of conflicting interests. I'll give you an example, from one of my startup's enterprise customers. This company needs to ensure that their high-end auto inventory remains in the same state through transport — the mileage, the car body, etc. They've had issue…

It is my understanding that the only functional difference between a database, and a blockchain, is the elimination of a trusted third party who would have to administer the database (and could, maliciously, alter that DB)

AFAICT, this is not such a problem where a third party cannot be trusted (the only incentive would be if they contacted you and tried to bribe the modification, which doesn't seem worth it).

Otherwise, if the DBA can be trusted, it's not clear to me that the blockchain offers any additional verification, encryption, audit-ability, etc -- and it doesn't seem to me that the "DBA cannot be trusted" is a sufficiently possible risk scenario to try to eliminate from the equation

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#208

Post by chaps »

sebmellen wrote: post #184
bb88 wrote: post #129

Earlier quoted context omitted.

The picture of the car is not protected by hard crypto until it's inserted into the blockchain. Until it is inserted the trust chain breaks at the questions of: When was it taken? Who was taking the picture? What is the picture of? The car to be protected? Or someone else's car. Blockchain works for currencies, since currencies are just numbers in a ledger. And numbers can be easily secured with strong crypto.

See my response to the grandparent comment for more details. > When was it taken? We currently verify this by including the last Bitcoin block hash in the photo, giving us a ~10 minute time window in which the photo was taken. Also, the whole handoff period is under 20 minutes, so the transporter only has access to the cars for 20 minutes (with many others around), before a timestamp is required. > Who was taking the…

Your company sounds pretty awful to work for, where suggestions like, "Watch the employees at all times" are apparently taken seriously.

Had an interview for a company like that once, where they required that no work-related communication happen outside of their chat client. And they had cameras to check for that. The turnaround rate was through the roof.

I genuinely hope that you'll try and solve these problems using other methods. Building these systems just makes your employee's lives hell.

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#209

Post by sebmellen »

doonesbury wrote: post #203
sebmellen wrote: post #177

Earlier quoted context omitted.

No need to be so snarky. Could someone tweak the image? Of course. But as a practical concern, probably less than 20 people have the image manipulation skill it would take to do something like this in the ~20 minute handoff period. The transporters certainly don't. This is a bullshit argument, and you know it. And these pictures are not just of the odometer, but the entire car, including the VIN. Photoshopping all of…

I agree with the question: is anything really be solved here? No, not really. A db table of jpegs taken at different points in the hand off is essentially fine too. Carfax seems to so fine without blockchain. And really the bottom line is the end recipient: what recourse is there if the car shows up with too many miles?

The recourse is that the transporter doesn't get paid. Just a small adjustment to incentives massively changes the occurrence of damage to the car or anything similar.

If you're arguing to put everything in a spreadsheet, or have us control the database and do without timestamping, I don't know what to say to you. Blockchain works here. Our business model isn't changing because you're saying we don't need it. Build a system like this yourself and we'll talk about it then.

Carfax is a vertically integrated service with very little of the complexity we're dealing with. And of course you can make do without blockchain. People made do without electricity and power tools. But here it's a cheap, faster, easier to use, and more trusted alternative. What's wrong with that?

Re: Ask HN: What are real-life useful use-cases for blockchain (not currencies)?

#210

Post by sebmellen »

doonesbury wrote: post #204
_asummers wrote: post #163

Earlier quoted context omitted.

The power of a notary is that someone is legally verifying the state of the document under penalty of perjury. In this case, you don't trust the party doing the verification, by definition, and there's no second party, so I don't see what this solves. That there is an immutable log of the events is an implementation detail and could be solved with a write only DB completely independent of blockchain.

Agree. There are consequences if the notary lies. If bad data is posted to the blockchain ... Well ... So what? That's why I asked the original poster of scenario what the end receiver's recourse is if he gets a car with too many miles? Arguing about blockchain and what it did or was supposed to do will be immaterial by then.

As I responded to you in another comment, the recourse is that the transporter is not paid. This is laid out in a legal contract which references the timestamping system.
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