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How Blockchain Works

blockchain.mit.edu

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Re: How Blockchain Works

#91

Post by prostoalex »

thedancollins wrote: post #73
prostoalex wrote: post #65

Earlier quoted context omitted.

> The concept is truly revolutionary In what way? Publishing a DB dump with a checksum has been around for decades, and doesn't require a new user to download an entire history of deltas from day 1.

Because it finally provides a mechanism by which bad actors on a network could face repercussions for their activity. Consider how different the internet would be if hyperlinks were two-way rather than one-way. Again, it is not only about data, it is about the speed of transactability that would result when value could be exchanged instantaneously with radical transparency behind the actors on the chain. Bankers go a…

> it is about the speed of transactability

As somebody pointed out https://news.ycombinator.com/item?id=18076542 high transaction throughput is not exactly the killer feature of modern-day blockchains.

Re: How Blockchain Works

#92

Post by fartcannon »

Razengan wrote: post #86

I have yet to watch/read the link, or catch up on the hype, but why is "Blockchain" referred to in the singular? As in "the blockchain" or just "blockchain" (often capitalized.) Is there only one of its kind? Is "How Internet Works" grammatically correct? EDIT: I didn't see this was already asked in another comment.

I too want to know this. You'd think it would be "How (a) blockchain works" or "How blockchains work"... The way this is written feels like they're suggesting there is only one.

Re: How Blockchain Works

#93

Post by the_snooze »

w1nt3rmu4e wrote: post #89
thedancollins wrote: post #33

Over the past year I have gone from Blockchain enthusiast to more blockchain gadfly. The concept is truly revolutionary but the use cases I typically see trotted out are not compelling in any significant sense and could be solved without blockchain. I believe the reason for this is due to the fact that the true value of a blockchain solution is not in the data aspect of it (which everyone gravitates to and can quickl…

Honestly, I don't see why everyone hates blockchain these days. Two things are going on: 1. It's a potentially revolutionary technology (trust-less, decentralized, nearly tamper proof, etc) that hasn't yet found a killer app(s) at scale 2. We're in the middle of a gold rush with zillions of shit-coins really throwing off the signal to noise ratio This period will pass. Blockchain tech is maturing (PoS replacing PoW,…

>It's a potentially revolutionary technology (trust-less, decentralized, nearly tamper proof, etc) that hasn't yet found a killer app(s) at scale

I'd argue it has: cryptocurrency and all the criminal enterprises it supports (e.g., ransomware). If you're willing to enter legally-enforceable contracts with other parties, then "trustless" and "decentralized" don't matter all that much to you.

Re: How Blockchain Works

#94

Post by sparkzilla »

Moodles wrote: post #62
sparkzilla wrote: post #55

Earlier quoted context omitted.

My company aims to convert all the world's news into data. Please tell me another technology that will allow us to build a decentralised, failure-tolerant, censorship- and tamper-resistant archive of that data, that allows anyone to add data, and have it verified without a central authority, and that anyone can use to create news applications.

> my company .... decentralized Can you explain this step?

Good point. We are setting up a foundation to initially run the project, but even the foundation will be deprecated as we go forward. In fact its primary role will be to enable further decentralisation i.e. to make sure that no single party can monopolize the system through various consensus methods.

Re: How Blockchain Works

#96

Post by neospice »

vec wrote: post #87
neospice wrote: post #81

Earlier quoted context omitted.

Please forgive my ignorance if I’m missing something obvious but in your PGP public key tampering example, wouldn’t this attack be ineffective against a blockchain that is stored in multiple peers. I.E your hashes wouldn’t match those of the peer copies of the blockchain?

Nope. The whole point of proof of work is that it informs clients which version to consider authoritative in the case of a conflict. If my tampered copy has higher proof of work than the peer with the correct version then, by definition, mine is correct and the other peer's is outdated. Correctly implemented peers will recognize this and overwrite their local cache with mine, and even if they don't other peers will a…

How is "higher proof of work" defined in this context? Also, doesn't consensus of the majority of peers have any bearing on which is more authoritative? I.e. if all nodes except for your malicious node report a single chain, why would yours not be rejected?

Re: How Blockchain Works

#98

Post by proxylittle »

Moodles wrote: post #20
gibsons77 wrote: post #17

Earlier quoted context omitted.

Well.. It will change some aspects of our world. Particularly financial assets at first, but increasingly it will play a role in any peer to peer exchange requiring trust. Simple past examples are systems like OpenPGP that bind public keys to owners. Programmable blockchains allow generalized applications requiring decentralized trust. A good example of a use of blockchain outside of financial assets is in trust mana…

I have a PhD in cryptography. Please be precise. Exactly what problem will blockchain solve for vehicles? You can't just hand wave and say stuff like "decentralized trust management" and expect us to nod along.

Is it just me or do the replies I'm seeing come across condescending and unsubstantial? I'm also missing why your PhD in cryptography is any important for the sake of the argument. We are not you in regards to your last remark by the way: "...expect us to nod along". But since you are looking for a good argument to support your confirmation bias, blockchain itself doesn't solve anything. It's just a data structure and a tool. The problem solving happens in the bigger picture, e.g. "decentralised trust management".

But let me ask you this: exactly what problem will a database/tree/file solve for vehicles or currencies? We can agree upon that what you are asking and looking for can't be answered or will get a reply similar to: we don't have that problem. You may have asked the wrong question though.

Let me be more precise and create a problem that doesn't exist but for programming purposes I want these requirements: many users should be able to read a (hardly) modifiable data structure that gets more resilient the more use it and that is a singleton who everybody has access to (call it decentralised if you will). Blockchain sounds like a perfect fit doesn't it? Now, when we replace the data structure keyword with OS and resiliency with speed, we can agree upon that this sounds like a decentralised operating system (Ethereum or whatnot).

Don't get me wrong. I don't see any problems that need to be solved with blockchain right now either. But clearly there is a trend in cryptocurrencies and decentralisation that seems to be important to a lot of people. There are tons of problems that need solving: trust misuse, censorships, privacy issues, advertising and so on. That there is a need for a change is obvious. That this change started with blockchain technology is good. I'm also sure cryptography is important to you too. Why not embrace an emerging technology that benefit your field of study?

Re: How Blockchain Works

#99

Post by thedancollins »

lawn wrote: post #76
prostoalex wrote: post #65

Earlier quoted context omitted.

> The concept is truly revolutionary In what way? Publishing a DB dump with a checksum has been around for decades, and doesn't require a new user to download an entire history of deltas from day 1.

The term blockchain should come with a way to decide consensus, like proof-of-work or possibly proof-of-stake. This is a solution to decentralized consensus which is a truly revolutionary concept.

From a technical perspective, yes. But the case for blockchain is difficult to make from a technical perspective so I do not bother talking about it. The tech struggles to be viable. With that said, everything is impossible .. until it is not. Somebody will figure it out.

Re: How Blockchain Works

#100

Post by vec »

thedancollins wrote: post #73
prostoalex wrote: post #65

Earlier quoted context omitted.

> The concept is truly revolutionary In what way? Publishing a DB dump with a checksum has been around for decades, and doesn't require a new user to download an entire history of deltas from day 1.

Because it finally provides a mechanism by which bad actors on a network could face repercussions for their activity. Consider how different the internet would be if hyperlinks were two-way rather than one-way. Again, it is not only about data, it is about the speed of transactability that would result when value could be exchanged instantaneously with radical transparency behind the actors on the chain. Bankers go a…

> Bankers go away

People will still need loans. People will still want low risk investment vehicles to "store" their wealth in. At least some sizable number of them will want an institutional actor to handle operational security and insure against key loss.

> auditors go away

The blockchain mostly guarantees that a ledger hasn't been tampered with, but it doesn't guarantee that the transactions were correct and complete in the first place. Plus, it's trivially easy to transfer funds without it registering on the ledger; all I have to do is create a wallet and give the private key to you out of band somehow.

> credit requirements for market participation go away.

There are no credit requirements today, as long as you're only spending funds you have on hand. Credit requirements allow an actor to spend funds they don't actually possess with a reasonable expectation that they will be willing and able to produce those funds (plus interest) at some later date. Having the ledger public reduces, but doesn't eliminate, the need for the actual providers of those temporary funds to want to form some expectations of future performance.

Most of the ancillary infrastructure that's grown up around fiat currencies is there for really good reasons, and most of those reasons don't automatically go away when the underlying currency type changes.

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