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by jasode 3230 days ago
Author provides 2 examples: (1) blockchain and (2) big data Hadoop map reduce

(1) blockchain: most arguments about blockchain always being replaceable with a traditional single node central database conveniently leaves out the constraint for decentralized control. Yes, if you change the ideal goals for the solution, of course you can propose the traditional solution. (E.g. a government central database of property records does not solve the same problem as a decentralized blockchain of property records.)

The problems that blockchains are attempting to solve is real. The more interesting discussion is whether the costs of implementation (whether Proof-of-Work or Proof-of-Stake) will ever deliver on that promise. Two possibilities: (1) subsequent failed attempts of blockchains eventually lead computer scientists to a theorem that states any decentralized scheme always costs more than the economic value returned. (The theorem would be similar to the ironclad conclusions of CAP theorem or Godel's Incompleteness Theorem and also similar to discovering you _can_ synthesize gold but the cost (of a nuclear reactor) to do it costs more than the gold itself.) Or (2) more computer science thinking finally makes blockchains feasible for real world applications. Feasibility includes cpu costs, transactions-per-second, 51% attacks, rogue forks, etc.

(2) Hadoop map reduce: he writes...

>"The entire business plan of a ton of companies [...] set up these huge data clusters based on Hadoop and write complex MapReduce queries for basic operations, and wait for the spice to flow. But there’s no end game. When asked, there’s no vision on what to do with the data that will actually make money"

Author should spell out exactly which data companies are spending millions gathering hundreds of terabytes/petabytes with zero clue what to do with it.

Yes, there are all sorts of examples out there of "solutions looking for a problem" but this particular essay is empty of insightful data points.

4 comments

His complaint isn't against the Blockchain or Hadoop, but against the people proposing their use for its own sake, without concern about whether it actually provides benefits.

He specifically says that virtual currencies themselves are a valid reason to use the Blockchain.

>His complaint isn't against the Blockchain or Hadoop, but [...] whether it actually provides benefits.

For his blockchain example, I couldn't find his Dutch handicap parking story via Google for more details so I don't know if a traditional central database would solve the same exact problem.

I'm saying that virtually all dismissals of a blockchain in favor of central databases almost always removes the benefits of decentralization. The ironic part is that the skeptics don't realize that the central db "solution" is incomplete when compared to all the decentralized goals (e.g. multiple witnesses guarding against tampering, potentially lower cost ownership verification, etc). Yes, if one changes the rules or moves the goal posts around, one can replace a decentralized blockchain with MySQL. If somebody is the skeptic, does he even notice that he performed that sleight-of-hand in his argument?!?

Besides shandor's point, the Blockchain didn't invent decentralized data sharing. I, along with every developer of accounting systems in my country, was writing hash-chained ledgers before the Bitcoin paper was even published.

The innovation brought by the Blockchain was using a proof-of-work to achieve consensus and avoid double-spending in a network of semi-anonymous peers.

The vast majority of proposed uses of the Blockchain for non-currency reasons that I've seen do not suffer from this problem, and therefore do not need the innovation brought by it.

>The vast majority of proposed uses of the Blockchain for non-currency reasons that I've seen do not suffer from this problem, and therefore do not need the innovation brought by it.

Then we've been exposed to different examples. I've not seen any non-trivial proposed uses for distributed consensus blockchain that can be exactly replaced by a central db. Replacement always involves relaxing a constraint (e.g. trust the centralized organization not to tamper, etc).

shandor's point can be generalized to "solutions looking for a problem" which I already agreed with. Where I differ is based on the actual debates on the serious uses of blockchain I've seen, I don't see that technology abuse as the overwhelming situation.

Again, you keep pushing the false dichotomy of "blockchain vs centralized". Distributed and verifiable data sharing existed before the Blockchain!
>Distributed and verifiable data sharing existed before the Blockchain!

But I'm not talking about any distributed data sharing such as p2p bittorrent with hash verification, or git/github, or NNTP Usenet, or the distributed accounting system you worked on, etc. For purposes of this thread, "blockchain" is synonymous with decentralized trust which I believe is how it's usually used.

I can agree that blockchain didn't invent "decentralized data sharing" but that's not relevant to my point.

I think you're still missing the point. I understood that the author was criticizing the mindset of the companies which "want to use blockchain". In those cases, "moving the goal posts" is actually the sensible thing to do, when said companies are looking into the blockchain without understanding if they are actually going to benefit from the core blockchain benefit of decentralization.

There should be nothing wrong in moving the goal posts, when the original goal seems to be the wrong one.

Yup. Most of the goalpost-moving happens to make "decentralization" the goal in the first place, so elaborate solutions can be devised to eliminate the need to trust partners not to falsify their record of the contract, despite the fact that in many real world situations if they can't trust their partners that far, there's no way they should be giving them access to property, resources or cash in the first place.
>For blockchain, I couldn't find his Dutch handicap parking story via Google for more details so I don't know if a traditional central database would solve the same exact problem.

Maybe the "exact same problem" is the wrong thing to try to solve? It might not be a problem in the first place (by itself), just a re-formulation of the actual problem so that it's solvable by blockchain, which seems to be the author's point.

Regarding your point about economic value. Things don't have any in inherent economic value. Price is a function of demand and supply. A thing is only worth something because somebody wants to do something with it.

So, a theorem which says decentralised scheme "costs" more than economic value is not possible to have.

For example, say gold is very expensive to synthesise. But if it is absolutely necessary for some job the cost becomes worth i9t and the price would reflect that.

But do you need decentralization to distribute benefits cards to the disabled?

The point is that many of the proposed uses don't actually benefit from decentralization in any meaningful way, so you might as well save a pile of headaches and use a standard database.

Blockchain isn't decentralized. The network is run by a handful of companies, mainly in China.
Even if every chinese miner decided to collude and generate invalid blocks the result would be those blocks being rejected by the standard bitcoin nodes in favor of any valid blocks. Having a majority of hashing power does give them power but it definitely doesn't give them control over bitcoin.

Mining is centralized but bitcoin consensus is decentralized.

I was talking about blockchains. Are you talking about Bitcoin?

blockchain != Bitcoin

blockchain != Ethereum

Reasons other blockchains won't exhibit the same behavior as the two most used ones? None.
Reasons N+1 th implementation wont exhibit the same behavior as the N most used ones ?

How is that none ?