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by poiuiopkj 2070 days 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.
2 comments
root_axis 2070 days ago
> It limits who is possibly at fault to a minimum of one of two parties

The blockchain adds nothing useful to the setup, you could have the exact same level of confidence if each link in the chain e-mailed a photo to a central inbox.

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smt88 2070 days 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).
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sebmellen 2070 days 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.

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smt88 2070 days 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/verif...

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