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I’ll paste what I wrote in https://cryptologie.net/#article_555 https://cryptologie.net/#article_555 The simplest abstraction is to see cryptocurrency / blockc

by baby 5y ago

I’ll paste what I wrote in https://cryptologie.net/#article_555 https://cryptologie.net/#article_555 The simplest abstraction is to see cryptocurrency / blockchain / distributed ledger technology as a database running on a single computer. Everybody can access this database and there’s some simple logic that allows you to debit your account and credit someone else’s account. The computer has a queue to make sure transactions are processed in order. Blockchains that support smart contracts allow for people to install programs to that computer, which will add a bit more logic than simply debiting/crediting accounts. Others can then just send transactions to this computer to make a function call to any program (smart contract) that was installed on the computer. The cool thing really is that we’re all using the same computer with the same database and the same programs. Now in practice, nobody would trust a single point of failure like that. What if the computer crashes, or burns in a fire? Distributed systems to the rescue! We use distributed system protocols to run the same database on many computers distributed around the world. These distributed system protocols effectively simulate a single database/computer so that a few computers failing doesn’t mean the end of the blockchain. On top of that, we refuse to trust the computers that participate in this protocol. They could be lying about the balance in your account. We want the computers to police one another and agree on the database they are simulating. That’s where consensus protocols are used: to make the distributed database secure even when some of the participants are malicious. And that’s it. That’s blockchain tech for you. The obvious application is money, as the secure and simulated single computer is useful to simplify a payment system, but really any distributed database that cannot trust some of its participants can benefit from the advances there.

FabHK 5y ago
Yes, it is a slow computer that uses the resources of about a billion modern computers. (Note that you could achieve basically any desired fault tolerance with a minuscule fraction of that with a trusted central authority.)
- programmarchy 5y ago
  Your second statement presupposes central authorities can be trusted. Some presuppose that they cannot.
  - FabHK 5y ago
    Let me quote from a 2012 interview with Bruce Schneier about his book Liars and Outliers: Q: Given the dangers out there, should we trust anyone? Isn’t “trust no one” the first rule of security? Bruce: It might be the first rule of security, but it’s the worst rule of society. I don’t think I could even total up all the people, institutions and systems I trusted today. I trusted that the gas company would continue to provide the fuel I needed to heat my house, and that the water coming out of my tap was safe to drink. I trusted that the fresh and packaged food in my refrigerator was safe to eat – and that certainly involved trusting people in several countries. I trusted a variety of websites on the Internet. I trusted my automobile manufacturer, as well as all the other drivers on the road. I am flying to Boston right now, so that requires trusting several major corporations, hundreds of strangers – either working for those corporations, sitting on my plane or just standing around in the airport – and a variety of government agencies. I even had to trust the TSA [US Transportation Security Administration], even though I know it’s doing a lousy job – and so on. And it’s not even 9:30am yet! The number of people each of us trusts every day is astounding. And we trust them so completely that we often don’t even think about it. We don’t walk into a restaurant and think: “The food vendors might have sold the restaurant tainted food, the cook might poison it, the waiter might clone my credit card, other diners might steal my wallet, the building constructor might have weakened the roof, and terrorists might bomb the place.” We just sit down and eat. And the restaurant trusts that we won’t steal anyone else’s wallet or leave a bomb under our chair, and will pay when we’re done. Without trust, society collapses. And without societal pressures, there’s no trust. The devil is in the details, of course, and that’s what my book is about. https://www.schneier.com/news/archives/2012/02/bruce_schneier_on_tr.html https://www.schneier.com/news/archives/2012/02/bruce_schneie...
    - baby 5y ago
      You can’t generalize that
- baby 5y ago
  "trusted central authority"
sirsinsalot 5y ago
All that text and still not a single, solid, real world application. Idealistic waffle.
- baby 5y ago
  Do you have a question I can help answer perhaps?

by baby 5y ago

FabHK 5y ago

Yes, it is a slow computer that uses the resources of about a billion modern computers. (Note that you could achieve basically any desired fault tolerance with a minuscule fraction of that with a trusted central authority.)

programmarchy 5y ago
Your second statement presupposes central authorities can be trusted. Some presuppose that they cannot.
- FabHK 5y ago
  Let me quote from a 2012 interview with Bruce Schneier about his book Liars and Outliers: Q: Given the dangers out there, should we trust anyone? Isn’t “trust no one” the first rule of security? Bruce: It might be the first rule of security, but it’s the worst rule of society. I don’t think I could even total up all the people, institutions and systems I trusted today. I trusted that the gas company would continue to provide the fuel I needed to heat my house, and that the water coming out of my tap was safe to drink. I trusted that the fresh and packaged food in my refrigerator was safe to eat – and that certainly involved trusting people in several countries. I trusted a variety of websites on the Internet. I trusted my automobile manufacturer, as well as all the other drivers on the road. I am flying to Boston right now, so that requires trusting several major corporations, hundreds of strangers – either working for those corporations, sitting on my plane or just standing around in the airport – and a variety of government agencies. I even had to trust the TSA [US Transportation Security Administration], even though I know it’s doing a lousy job – and so on. And it’s not even 9:30am yet! The number of people each of us trusts every day is astounding. And we trust them so completely that we often don’t even think about it. We don’t walk into a restaurant and think: “The food vendors might have sold the restaurant tainted food, the cook might poison it, the waiter might clone my credit card, other diners might steal my wallet, the building constructor might have weakened the roof, and terrorists might bomb the place.” We just sit down and eat. And the restaurant trusts that we won’t steal anyone else’s wallet or leave a bomb under our chair, and will pay when we’re done. Without trust, society collapses. And without societal pressures, there’s no trust. The devil is in the details, of course, and that’s what my book is about. https://www.schneier.com/news/archives/2012/02/bruce_schneier_on_tr.html https://www.schneier.com/news/archives/2012/02/bruce_schneie...
  - baby 5y ago
    You can’t generalize that
baby 5y ago
"trusted central authority"

sirsinsalot 5y ago

All that text and still not a single, solid, real world application. Idealistic waffle.

baby 5y ago
Do you have a question I can help answer perhaps?