6 ms·

Indeed. Blockchain is a really clever piece of applied cryptography with very limited real-world use-cases.

by substation13 4y ago

otabdeveloper4 4y ago
The real-world use-cases are already covered by git.
- CuriousCosmic 4y ago
  Not all of them. There are two very specific use cases that it has value as: 1. A decentralised/trust-less "source of truth" for coordination between mutually distrusting parties. This was the "novel" innovation for Bitcoin and it's been refined with the less energy intensive consensus algorithms. Not everything needs this and arguably fairly few things do but for the projects that benefit from trust-less coordination as an option, I'm not sure there's a better alternative yet. 2. As a decentralised marketplace for a given resource. The most common one is the basic cryptocurrency which is a fee market for inclusion in the ledger. Past that however are Storage, Data routing (i.e. VPN or onion routing), and Verifiable Compute (or non-accuracy-critical compute like 3d rendering). Outside of those, I'd also argue it's useful for privacy preserving transactions (like monero, etc) but I know some people will disagree that that's "just for criminals". Don't get me wrong, a lot of cryptocurrency or blockchain projects are practically an abstraction over git or a database but there are a number of very useful things you can do with blockchains that you just can't do with git or a db.
  - JumpCrisscross 4y ago
    > trust-less "source of truth" for coordination between mutually distrusting parties This only works if everything of value is on the blockchain. Otherwise, the oracle problem makes regular databases a better solution.
  - root_axis 4y ago
    Doesn't really make any sense. A regular database with digital signatures chained per transaction gives you all the benefits without any of the downsides of a blockchain.
    - substation13 4y ago
      No, it doesn't. How do you build consensus around the signatures?
      - acdha 4y ago
        The same way humans have for millennia: relying on authority, reputation, and auditing. Blockchains have enormous overhead because they’re trying to be anonymous but once you need real-world connections you’re already giving that up, which makes it much cheaper to simply rely on those existing relationships. Historically, that was things like documents being stamped or sealed by a trusted third party witness, escrow agents to hold funds or property until some transaction finished, auditors confirming that a particular good was in the expected condition, etc. In every case, anonymity would be a negative because you want to know, for example, that your notary doesn’t have a criminal history or a reputation for sloppy record keeping. In the electronic era, that could be implemented using PKI where different parties register keys (or more likely corporate CAs) and use those to sign transactions or witness having seen a particular record. That’s similar to a blockchain in terms of trust but orders of magnitude more efficient and robust since it doesn’t require a network connection to a complex distributed service.
      - root_axis 4y ago
        What does that mean? The signatures are self-describing, you don't need to build a "consensus" around them.
        CuriousCosmic 4y ago
        How do you agree on which signatures or information are actually part of the database? How do you decide who gets to add new entries to the database? Unless there is some meaningful method for maintaining the current state and each atomic change to that state going backwards, you are losing security guarantees. You can go down the git route but history is trivially rewrite-able and while git is decentralised, it has no mechanism for coming to a consensus about which history is the right one. Now you are back to determining consensus. You can either just say "X is the authority" and use a hosted git repo but if that's not viable for your threat model, you are pretty much back to cryptocurrency style consensus (probably Proof of Stake or Proof of Authority depending on your threat model).
  - qznc 4y ago
    The "decentralized" is not a requirement. For example, nobody really needs a "decentralized marketplace". They just need a "marketplace". Mediation and arbitration are well known methods when trust is missing. A joint venture with a database can do anything the blockchain community built more efficiently.
- chris_wot 4y ago
  No, git uses a merkle tree, which the blockchain also uses. That’s the only similarity. It doesn’t rely on a massively distributed system to get the next time stamp for the next commit. Git is decentralised, not distributed. You get the whole git database (for want of a better word) when you clone it, unless you use the —unshallow option. git does not implement a block-chain.

Indeed. Blockchain is a really clever piece of applied cryptography with very limited real-world use-cases.

otabdeveloper4 4y ago

The real-world use-cases are already covered by git.

CuriousCosmic 4y ago
Not all of them. There are two very specific use cases that it has value as: 1. A decentralised/trust-less "source of truth" for coordination between mutually distrusting parties. This was the "novel" innovation for Bitcoin and it's been refined with the less energy intensive consensus algorithms. Not everything needs this and arguably fairly few things do but for the projects that benefit from trust-less coordination as an option, I'm not sure there's a better alternative yet. 2. As a decentralised marketplace for a given resource. The most common one is the basic cryptocurrency which is a fee market for inclusion in the ledger. Past that however are Storage, Data routing (i.e. VPN or onion routing), and Verifiable Compute (or non-accuracy-critical compute like 3d rendering). Outside of those, I'd also argue it's useful for privacy preserving transactions (like monero, etc) but I know some people will disagree that that's "just for criminals". Don't get me wrong, a lot of cryptocurrency or blockchain projects are practically an abstraction over git or a database but there are a number of very useful things you can do with blockchains that you just can't do with git or a db.
- JumpCrisscross 4y ago
  > trust-less "source of truth" for coordination between mutually distrusting parties This only works if everything of value is on the blockchain. Otherwise, the oracle problem makes regular databases a better solution.
- root_axis 4y ago
  Doesn't really make any sense. A regular database with digital signatures chained per transaction gives you all the benefits without any of the downsides of a blockchain.
  - substation13 4y ago
    No, it doesn't. How do you build consensus around the signatures?
    - acdha 4y ago
      The same way humans have for millennia: relying on authority, reputation, and auditing. Blockchains have enormous overhead because they’re trying to be anonymous but once you need real-world connections you’re already giving that up, which makes it much cheaper to simply rely on those existing relationships. Historically, that was things like documents being stamped or sealed by a trusted third party witness, escrow agents to hold funds or property until some transaction finished, auditors confirming that a particular good was in the expected condition, etc. In every case, anonymity would be a negative because you want to know, for example, that your notary doesn’t have a criminal history or a reputation for sloppy record keeping. In the electronic era, that could be implemented using PKI where different parties register keys (or more likely corporate CAs) and use those to sign transactions or witness having seen a particular record. That’s similar to a blockchain in terms of trust but orders of magnitude more efficient and robust since it doesn’t require a network connection to a complex distributed service.
    - root_axis 4y ago
      What does that mean? The signatures are self-describing, you don't need to build a "consensus" around them.
      - CuriousCosmic 4y ago
        How do you agree on which signatures or information are actually part of the database? How do you decide who gets to add new entries to the database? Unless there is some meaningful method for maintaining the current state and each atomic change to that state going backwards, you are losing security guarantees. You can go down the git route but history is trivially rewrite-able and while git is decentralised, it has no mechanism for coming to a consensus about which history is the right one. Now you are back to determining consensus. You can either just say "X is the authority" and use a hosted git repo but if that's not viable for your threat model, you are pretty much back to cryptocurrency style consensus (probably Proof of Stake or Proof of Authority depending on your threat model).
- qznc 4y ago
  The "decentralized" is not a requirement. For example, nobody really needs a "decentralized marketplace". They just need a "marketplace". Mediation and arbitration are well known methods when trust is missing. A joint venture with a database can do anything the blockchain community built more efficiently.
chris_wot 4y ago
No, git uses a merkle tree, which the blockchain also uses. That’s the only similarity. It doesn’t rely on a massively distributed system to get the next time stamp for the next commit. Git is decentralised, not distributed. You get the whole git database (for want of a better word) when you clone it, unless you use the —unshallow option. git does not implement a block-chain.