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Nothing proves that the timestamp accurately reflects when the photo was taken or that the photo itself is even accurate. If I wanted to joy-ride one of these c

Nothing proves that the timestamp accurately reflects when the photo was taken or that the photo itself is even accurate. If I wanted to joy-ride one of these cars I'd simply do so before taking the photo. The odometer display can also be trivially modified for the sake of a photo (i.e. roll back the odo for a photo and then revert to accurate numbers after the photo)

technoplato 6y ago
This has been the only comment I'm actually interested in seeing a response from parent commenter on.
- UweSchmidt 6y ago
  There is no solution for the oracle problem: someone has to input the truth, and that entity can just run a database. End of story. People made insane money with Bitcoin, Ethereum and others. People then dropped lots of other "coins" that eventually no one cared about. "Blockchain as useful technology" is the story to sell the next "coin". Employing a couple of devs and funding a few blockchain startups is trivial money in this context, often sponsored by "believers" (who got rich in the early days) Blockchain tech comes with inescapable complexities and problems: bugs and security issues can't be fixed in blockchain programs. Any trivial action on the blockchain requires mining, i.e. the very thing that's done with specialized hardware in areas where energy is cheap. My last point seems to be tangential, but do try it yourself with a small project on a private Ethereum chain, using geth, web3.js, there are good tutorials out there. Usually when you try out a fancy new tech you "get it" after a while, but I definitively did NOT see any way this is feasible.
dejj 6y ago
How do you undo any dents that may occur during a joyride though?
- root_axis 6y ago
  I'm not sure what you're asking. If the possibility of dents were enough to prevent joyrides then the entire conversation would be moot, blockchain or otherwise.
poiuiopkj 6y ago
The next entity in the supply chain would have an odometer that didn't match the picture that was previously posted. It limits who is possibly at fault to a minimum of one of two parties, which I'm sure could be narrowed down further by corroborating evidence. It highly discourages it because at the very least, you would be the first suspect with no real finger to point.
- smt88 6y ago
  That's true, but none of that is enabled by blockchain. You can do all of that with an append-only, distributed database that is cryptographically verifiable. You don't need a public blockchain (or any blockchain at all).
  - sebmellen 6y ago
    > an append-only, distributed database that is cryptographically verifiable You just described a blockchain. Why rebuild what already exists? A blockchain is a great drop-in solution and reduces our costs and implementation worries massively. And the distribution of this public blockchain is much more decentralized than we could ever achieve running our own nodes.
    - smt88 6y ago
      > You just described a blockchain. I purposefully did not describe a blockchain, although that depends on what your definition of blockchain is. If we're defining blockchain as something descending from Satoshi's 2008 paper, then what I described is not a blockchain. The distinction I'm making is one of trust. I was describing a database with centralized trust. > Why rebuild what already exists? A blockchain is a great drop-in solution and reduces our costs and implementation worries massively. I didn't say you should rebuild anything. It sounds like you think that the only easy-to-use, mature append-only databases with cryptographically verifiable logs (popularly called "ledger databases" these days) are blockchains. That's not true. All the major clouds have such databases now. > And the distribution of this public blockchain is much more decentralized than we could ever achieve running our own nodes. I still don't see any evidence (either from you or anyone else advocating blockchains) that this is good for you use case. Can you please explain an attack that is possible against something like Amazon's QLDB[1] but is impossible against a public blockchain? There's also the issue of speed and usage costs of public blockchains, not to mention the frequent bugs, 51% attacks, and other uncertainties that come up. We know the costs of building on public blockchains. I'm dying for someone to come up with a benefit that is only possible on that blockchain. Every time they try, it seems to be benefits that are shared with services like QLDB or a variety of FOSS solutions. 1. https://docs.aws.amazon.com/qldb/latest/developerguide/verification.html https://docs.aws.amazon.com/qldb/latest/developerguide/verif...
avalys 6y ago
Presumably, the first person who hands off the car (in a “known good” state) would also insert a photo of the odometer into the blockchain.

technoplato 6y ago

This has been the only comment I'm actually interested in seeing a response from parent commenter on.

UweSchmidt 6y ago
There is no solution for the oracle problem: someone has to input the truth, and that entity can just run a database. End of story. People made insane money with Bitcoin, Ethereum and others. People then dropped lots of other "coins" that eventually no one cared about. "Blockchain as useful technology" is the story to sell the next "coin". Employing a couple of devs and funding a few blockchain startups is trivial money in this context, often sponsored by "believers" (who got rich in the early days) Blockchain tech comes with inescapable complexities and problems: bugs and security issues can't be fixed in blockchain programs. Any trivial action on the blockchain requires mining, i.e. the very thing that's done with specialized hardware in areas where energy is cheap. My last point seems to be tangential, but do try it yourself with a small project on a private Ethereum chain, using geth, web3.js, there are good tutorials out there. Usually when you try out a fancy new tech you "get it" after a while, but I definitively did NOT see any way this is feasible.

dejj 6y ago

How do you undo any dents that may occur during a joyride though?

root_axis 6y ago
I'm not sure what you're asking. If the possibility of dents were enough to prevent joyrides then the entire conversation would be moot, blockchain or otherwise.

poiuiopkj 6y ago

The next entity in the supply chain would have an odometer that didn't match the picture that was previously posted. It limits who is possibly at fault to a minimum of one of two parties, which I'm sure could be narrowed down further by corroborating evidence. It highly discourages it because at the very least, you would be the first suspect with no real finger to point.

smt88 6y ago
That's true, but none of that is enabled by blockchain. You can do all of that with an append-only, distributed database that is cryptographically verifiable. You don't need a public blockchain (or any blockchain at all).
- sebmellen 6y ago
  > an append-only, distributed database that is cryptographically verifiable You just described a blockchain. Why rebuild what already exists? A blockchain is a great drop-in solution and reduces our costs and implementation worries massively. And the distribution of this public blockchain is much more decentralized than we could ever achieve running our own nodes.
  - smt88 6y ago
    > You just described a blockchain. I purposefully did not describe a blockchain, although that depends on what your definition of blockchain is. If we're defining blockchain as something descending from Satoshi's 2008 paper, then what I described is not a blockchain. The distinction I'm making is one of trust. I was describing a database with centralized trust. > Why rebuild what already exists? A blockchain is a great drop-in solution and reduces our costs and implementation worries massively. I didn't say you should rebuild anything. It sounds like you think that the only easy-to-use, mature append-only databases with cryptographically verifiable logs (popularly called "ledger databases" these days) are blockchains. That's not true. All the major clouds have such databases now. > And the distribution of this public blockchain is much more decentralized than we could ever achieve running our own nodes. I still don't see any evidence (either from you or anyone else advocating blockchains) that this is good for you use case. Can you please explain an attack that is possible against something like Amazon's QLDB[1] but is impossible against a public blockchain? There's also the issue of speed and usage costs of public blockchains, not to mention the frequent bugs, 51% attacks, and other uncertainties that come up. We know the costs of building on public blockchains. I'm dying for someone to come up with a benefit that is only possible on that blockchain. Every time they try, it seems to be benefits that are shared with services like QLDB or a variety of FOSS solutions. 1. https://docs.aws.amazon.com/qldb/latest/developerguide/verification.html https://docs.aws.amazon.com/qldb/latest/developerguide/verif...

avalys 6y ago

Presumably, the first person who hands off the car (in a “known good” state) would also insert a photo of the odometer into the blockchain.