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Comment Re:Much more than barcodes (Score 1) 109

You just crypto-sign records and publish the (possibly encrypted) ledger.

If the entire DB was encrypted and published every time it was modified (many times per second) how could that possibly be a better solution than a blockchain? If you only encrypted and published the diffs, then wouldn't the chain of diffs pertaining to a single item be functionally the same as a blockchain, other than being scattered and more difficult to verify?

You're totally correct. A classic DBMS is just an efficient way to map a series of immutable transactions into a current state that can be queried efficiently: in it's most pure form it's just a complete transaction log, an initial empty state, a mapping from state+transaction->state, and a bunch of caching to aid in querying. So the transaction log is exactly equal to your chain of diffs.

Is the chain of signed diffs the same as a blockchain? Not quite. They are both chains, but transactions in the diff chain are not revokable (they are signed and can be upheld in court, etc,) whereas the blockchain transactions only become effectively non-revokable by consensus (requiring time and lots of compute power.) So, signing is much faster and cheaper than consensus. Scattered is second reason signed transactions are better: I only need to keep my copy of a transaction to prove it happened, blockchain requires I go out and find the consensus longest chain to prove the transaction is recorded. So, signed is safer and faster again as long as I can keep my own data.

Comment Re:Much more than barcodes (Score 2) 109

And you don't need a blockchain to fix the relational db tampering issue. You just crypto-sign records and publish the (possibly encrypted) ledger. Sign-and-register is technology that works and has been around for long before computers even existed.

The only thing blockchain solves is the double-spend problem. And that isn't an issue for WallMart's solution.

Comment Re:Nope (Score 1) 598

Yeah, this. OK so I know it's 8AM on the US west coast where my daughter lives, and in Japan where my MIL lives, and in the Czech Republic where my parents are. That still doesn't tell me a damn thing about what time it is over there - can I call them? Are they home? At work?

This is an idiotic solution to a problem that doesn't exist.

It really helps all the people living at the exact North Pole.

Comment Re:Why? (Score 2, Funny) 190

NASA has how many years experience in this area and how many has SpaceX got?

You Luddite!

Elon Musk has the expertise in the 100km/hr vehicle space from his Tesla work.
Elon Musk has the expertise in working with high-ISP energy systems from his battery and solar city work.
Elon Musk has the expertise in the 500km/hr vehicle space from his Hyperloop work (including low-cost bridges and tunnels and vomit bags.)
Elon Musk has the expertise in reusing the booster tin-can in rockets (getting 200lbs of rocks back from the moon was so expensive because we forgot to make the first stage reusable.)
Elon Musk has the expertise to go to Mars because he said so, and the turn-around time of the rockets is just a few days.

So, sit in the luxury space capsule and watch the blickenlights while he fuels that puppy up.

Comment Re:Of course (Score 2) 332

Agreed. Very few people (police included) wake up and say "I want to be a jerk today, escalate lots of situations, get complaints filed against me, and be in a bad mood all day 'cos I didn't abuse someone enough."

Once they see being reasonable, and taking the professional stance, works as well or better than abusing the other person, they internalize the new behavior pretty fast. They probably go home feeling more professional and happier, camera or no camera.

Comment Re:Greedy (Score 2) 102

People are starving while Gate$ hoards 78 billion dollars in cash. That makes sense.

Somewhere, a computer has { BillGates: 78,000,000,000 }. So what?

Interest rates are effectively zero right now. Hoarding is obviously not a way to make money, nor does it impact anyone's ability to borrow money and be productive.

Hoarding corn, or gold, or Titan-X graphics cards, or elephants, or opera singers would be a dick move. Hoarding money is pretty value neutral.

Comment Re:Not surprising (Score 4, Interesting) 165

Bitcoin as an idea is very interesting but, in actual function, it's a scam. I wanted to learn more about it a year ago and so bought some mining ASICs. It doesn't take long before you realize that your magic money printing device was sold to you at a cost that means you will invariably lose money. Which makes sense. If I have a magic money printing device, why the hell would I sell it to you instead of running it myself?

Um, because of reality? In this case, cost of capital:

If I can make a machine for $900 that generates $100/year forever, I get an 11% return on capital.
If I can sell it for $1000, I get an immediate return of $100, and can build another machine and repeat the process. At one per day, I make $36,500 in my first year.

If the risk free interest rate is around 3%, the second plan is worth 10x as much as the first plan.

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