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AWS and Blockchain

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Re: AWS and Blockchain

#231

Post by cmckn »

BatteryMountain wrote: post #201
runeks wrote: post #167

Blockchain was invented to solve one particular problem: distributed consensus on a sequence of transactions, where the choice of which transaction to include from a set of conflicting transactions is irrelevant. The latter property here is key to understanding where blockchain is useful. It was created to solve the "double spend problem", ie. two transitions that spend the same coin but send it to different recipien…

What you are referring to is a distributed ledger, built on top of a blockchain data structure. The word Blockchain is so overloaded, people forget you can build a "blockchain" in 50 lines of code if not less. "Mining" new blocks is added on top of that, it's not a hard requirement - you can just create new blocks and link them up. You can choose to "mine" on CPU (slow) or on the GPU, if you want "mining" at all. You…

I think you’re just describing merkle trees; and “blockchain” in popular usage includes the consensus mechanism (mining or otherwise).

Re: AWS and Blockchain

#232

Post by bongobingo1 »

uncletammy wrote: post #216
runeks wrote: post #167

Blockchain was invented to solve one particular problem: distributed consensus on a sequence of transactions, where the choice of which transaction to include from a set of conflicting transactions is irrelevant. The latter property here is key to understanding where blockchain is useful. It was created to solve the "double spend problem", ie. two transitions that spend the same coin but send it to different recipien…

Although I take slight issue with how you've worded it, I think I'm in agreement. I'll attempt to add clarification to the parts I find difficult to parse. Blockchains only ensure that coins are never spent twice. They make no attempts to ensure that coins are sent to the correct recipients. At the end of the block, they only care that debits are equal to credits. This can be confusing because the term "double spend"…

> Blockchains only ensure that coins are never spent twice. They make no attempts to ensure that coins are sent to the correct recipients. At the end of the block, they only care that debits are equal to credits.

I know the origin is tightly linked to bitcoin, but I feel like even this muddies the definition.

Blockchains are not implicitly related to "coins", more facts? contracts? Maybe that's a useless nit to pick, or only useful in this thread where the GP was trying to layout where blockchains are useful (eg: distributed facts - that happen to often be wealth transfer).

Or do I have it all wrong? I admit to not having much experience with them, but from the few random (non-btc) meet up groups talks I saw a decade ago, it was all about consensus more than anything. Ironically before the current NFT craze, the talk I remember most was one about using NFTs to authenticate stuff like (non-programatically-generated) album/artwork ownership and allowing users to resell in a second hand digital market.

I assume you could build a mastodon like that distributes and "authenticates" posts via a blockchain - perhaps with terrible performance though.

Re: AWS and Blockchain

#233

Post by quickthrower2 »

abiro wrote: post #228
quickthrower2 wrote: post #223

Earlier quoted context omitted.

This somewhat assumes blockchain can also deliver on privacy. Perhaps full encryption of the data is enough. But who is paying for all the nodes? Another way to do this without the blockchain is open standards (think… HTML for example!) and software that lets you export. Where possible run this software open source on the desktop or as an open source web app. Think Photopea as the pinnacle here. The blockchain or no…

Re costs: it’s decreasing rapidly. Solana is within 100x of DynamoDB prices so costs are soon becoming negligible. At that point costs can be taken over by the app developer or paid by users on a subscription basis. There are also decentralized consensus mechanisms that don’t rely on paying fees (FBA, delay functions). Idk which will succeed. Re open standards and “software that lets you export”: we’ve had this for t…

Thanks. Keeping an open mind! This is the best blockchain argument I have heard. At least in terms of what I value.

Re: AWS and Blockchain

#234

Post by function_seven »

v-erne wrote: post #195
smt88 wrote: post #24

I had a real experience that perfectly reflects the research presented here (safer ledgers useful, blockchains are not). I accidentally got wrapped up in a project to automate some HR functions, and the product manager demanded that it must be blockchain because blockchains are the future. It turns out that append-only databases are well-suited for HR records, and (especially when dealing with things like background…

>>It turns out that append-only databases are well-suited for HR records It may seem so, bu then You find out what are Your governments limit's for storing workers data, and Your company lawyers forces You to make it possible to delete everything that past that limit to limit legal risk and be gdpr compliant. And at this moment You find out that world is not constant and far from Your ideal model of spherical cow.

Can we design an append-only database that also allows for deletions if you replace those deletions with a direct reference to the hash that was once computed at that point in the chain?

Yes, I know this isn’t strictly “append only”, but it still gives the ability to prevent silent updates and silent deletes. Any record that’s deleted must be replaced with something that indicates that it was deleted.

Re: AWS and Blockchain

#235

Post by dale_glass »

mike_hearn wrote: post #226
dale_glass wrote: post #211

Earlier quoted context omitted.

Trust is expensive, lack of trust is even more so. Say, how would you build a skyscraper without trust? Are you going to set up an on-premises laboratory to test the quality of the concrete and steel? Are you going to personally verify the entire building's plans? Check whether the geological study was accurate? Follow every worker around to make sure they don't cut corners anywhere? The less you can trust that the m…

"you going to set up an on-premises laboratory to test the quality of the concrete and steel?" This isn't a good example because there are whole infrastructures to verify that buildings are being made "to code" and quality of materials is a part of that. E.g. this lab that tests steel: https://www.leica-microsystems.com/science-lab/steel-the-all... Now what you're getting at is, OK, now you have to trust the lab. But…

Yes, but even that is potentially troublesome. If you're in a low trust environment, then probably nobody trusts the labs either.

Like, why do the labs exist? Because the building companies really, really wants to build a solid building but the concrete industry is oddly shady? Or because there's an official/unofficial requirement for it? If the second, you easily end up with labs that rubber stamp whatever you want them to.

Trust in this sense is something that needs to be encouraged society-wide. You can patch imperfections, but there's a very real limit to how practical that is.

Re: AWS and Blockchain

#236

Post by qeternity »

marcell wrote: post #132

Blockchain skeptics are all defending the tech of the current financial system, and implicitly arguing it can’t be improved. They are wrong. The tech underlying the current system is really bad. For example: (1) How can I perform an atomic transaction across two stock exchanges? (2) How can I take stock held on one exchange, and use it as collateral on an unaffiliated lending platform? (3) How can I launch a new fina…

> (1) How can I perform an atomic transaction across two stock exchanges?

I'm not sure why you're mandating across two stock exchanges? If you want to swap two assets in a single transaction, there is a very mature market for this. This has more to do with CPAMM vs. CLOB than it does anything else.

> (2) How can I take stock held on one exchange, and use it as collateral on an unaffiliated lending platform?

Well, assets aren't held on exchanges...but again, there is a huge industry that facilitates this.

> (3) How can I launch a new financial app, as a small startup, and open it to assets held on ETrade.

This has more to do with ETrade than anything else. It's like saying how can I launch a startup and get my product in every Walmart store...well you need their cooperation.

> All of these are impossible in the current system.

Absolutely not even remotely true. Just because you don't know, doesn't mean it's not possible.

Re: AWS and Blockchain

#237

Post by mike_hearn »

dale_glass wrote: post #235
mike_hearn wrote: post #226

Earlier quoted context omitted.

"you going to set up an on-premises laboratory to test the quality of the concrete and steel?" This isn't a good example because there are whole infrastructures to verify that buildings are being made "to code" and quality of materials is a part of that. E.g. this lab that tests steel: https://www.leica-microsystems.com/science-lab/steel-the-all... Now what you're getting at is, OK, now you have to trust the lab. But…

Yes, but even that is potentially troublesome. If you're in a low trust environment, then probably nobody trusts the labs either. Like, why do the labs exist? Because the building companies really, really wants to build a solid building but the concrete industry is oddly shady? Or because there's an official/unofficial requirement for it? If the second, you easily end up with labs that rubber stamp whatever you want…

There's not really such a thing as low trust/high trust society. That's an abstraction that sounds good but hides too much detail to be useful when discussing specific projects.

You can't just encourage everyone to trust everyone else. To the extent developed countries can be described as "high trust", it's not because they are just magically more trusting. They get that way because there are extensive and mostly working mechanisms to find and penalize betrayals of trust. Corruption is low in the west because corrupt people get caught and punished, and because once the problem gets small enough people won't just blindly accept it but will make an effort to report it and ensure it's resolved (vs when it's endemic).

Stuff like concrete mixing is commodity, lots of small firms scattered around the world. They compete on price and delivery time so there's a temptation to cut corners. Delivery time is easily understood and measured, so is price, if you can properly measure quality then you can switch between providers easily. The alternative is that someone fixes the trust issue another way, like a big centralized mega-brand or having to in-source everything, but that comes with bigger downsides.

Re: AWS and Blockchain

#238

Post by dynjo »

I've lost count of how many product owners have interchanged the word Database with Blockchain to try and score some PR points with their customers/bosses.

Re: AWS and Blockchain

#239

Post by jillesvangurp »

inkyoto wrote: post #215
jillesvangurp wrote: post #189

Earlier quoted context omitted.

Ledgers are quite easy to build. Git is a ledger. It doesn't use a block chain but it does link commits via their hashes; which makes it an audit proof ledger. Unless you can break the hashes, you can't modify its history. And git is used between many different developers and companies working on the same projects. It was actually designed for this use case. The reason git doesn't need blockchains for this is because…

> Ledgers are quite easy to build. Git is a ledger. It doesn't use a block chain but it does link commits via their hashes; which makes it an audit proof ledger. Unless you can break the hashes, you can't modify its history. Easy as an arm chair theory, impossible in practice without a complete rewrite of git from scratch. You are also disregarding the immutability of the data and the append-only property of stored d…

> Git is absolutely the wrong tool for the job as hashes in git are used as identifiers to identify a specific change, but not to cyrptographically checksum the document/the change to the data. Git commits can also merged, rewritten, squashed or deleted – something is absolutely unacceptable in the compliance space.

Read up on git internals, it's a very elegant and simple design and you seem to assume a few things about it that are flat out wrong. A git repository is in fact a Merkle tree. Every commit is chained to the previous commit via a hash that includes the commit content and the hash of the previous commit. So, git history is immutable. You can't modify commits without breaking the chain of hashes. It's by definition append only.

You can of course modify your local copy of a git repository and rewrite history (i.e. change all the hashes). But that makes it incompatible with upstream history. People tend to use this to clean up their local change history before they send it upstream. With the exception of force push (i.e. just overwrite the remote repository), there is no way to merge a rewritten history. In order to merge changes, there MUST be a shared commit with the same history. It's not optional.

Re: AWS and Blockchain

#240

Post by louwrentius »

runeks wrote: post #167

Blockchain was invented to solve one particular problem: distributed consensus on a sequence of transactions, where the choice of which transaction to include from a set of conflicting transactions is irrelevant. The latter property here is key to understanding where blockchain is useful. It was created to solve the "double spend problem", ie. two transitions that spend the same coin but send it to different recipien…

What real life use case - that resonates with regular people - would this solve?

Isn’t Blockchain just a convoluted solution to a problem nobody has?

(Which is the conclusion of the article)

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