[matthewaveryusa]

>contributing compute power is economically incentivized

I think this is the aspect in blockchain that has really been stretched. Most problems are within closed networks and solved with digital signatures -- is the act of signing a record proof of work? If you squint hard enough and razzle-dazzle it enough I could see how you could call it that -- or simply call it a database with a signature column :)

[shawnz]

> is the act of signing a record proof of work?

The idea behind proof-of-work is to add a cost to inserts, so that inserting wrong information is too costly to be profitable. Whereas inserting correct information makes you eligible for rewards that negate the cost of having inserted it.

[mumblemumble]

That one's always struck me. At least if you squint, that would imply that blockchain's fraud-prevention strategy hinges on nobody ever using the blockchain to handle anything too valuable or important.

[shawnz]

Yes, there is a limit to the security that a cryptocurrency can provide (like with anything else). The level of security provided is based on the market price: The higher the price, the higher the rewards, which increases the profitability of mining, thus leading to more miners, which then increases the amount of competition you'll have if you want to post wrong information. Since there is a fixed rate of new data which can be added, that's what defines the cost of inserting data to the blockchain.

An attacker with a lot of resources (>50% of current mining power consumption) could use their resources to post wrong information, but it would need to be profitable enough to make up for the immense costs. It's unlikely there would be such a situation where an attacker could recover the costs for such an attack. At best they would be spending a lot of money to cause a temporary network disruption as the "fair players" move to a forked coin or similar.

[mumblemumble]

So, I can see that argument following for something like Bitcoin. Though I think that part of that is because cryptocurrency doesn't actually have any intrinsic value. So an attack on, say, the Bitcoin network would also have the effect of devaluing the very thing you're trying to compromise.

But it does seem to be something you need to contend with when looking for new uses. Most new ideas people are thinking up have to do with something that exists outside the blockchain itself. And that, not Bitcoin, is what Azure Blockchain Service was really about. The merits of cryptocurrency as an application of blockchain are largely irrelevant to this discussion.

My sense is that the general pattern for most other uses is that the number of potential legitimate participants in the blockchain system is likely be inversely proportional to the overall importance of the thing the blockchain is trying to manage. Everyone can get in on something like CryptoKitties, but there are probably very few natural participants in a blockchain network for managing nuclear fuel resources.

[thebean11]

You can use it to handle anything whose value to an attacker is less than the cost of attacking the network as a whole right? May not be following though.

[this_user]

That is true, but it's also useless for almost all applications. Because in the real world agreements, contracts, and laws exist to create trusted relationships between parties. Relying on an inefficient technical solution instead is neither necessary nor desirable.

[jandrese]

I'm always saddened that the energy that goes into those blockchain signatures is basically wasted.

Why couldn't bitcoin work by having the miners fold proteins or something? Proof of work comes from advancing the state of the art just a hair each time. Imagine if all of the computation power being used to prop up bitcoin were also doing something productive?

[motohagiography]

Arguably, it's doing something very desirable. Maybe invent a protein coin?

[hackinthebochs]

These already exist, e.g. foldingcoin. One problem is that they require a centralized authority to approve and distribute workloads, and so this entity has undesirable power over the network. I do believe there are some cryptocurrencies where you can submit arbitrary workloads and you pay for it with the currency of the network. But they never took off, probably because they don't match the efficiency and/or data privacy of AWS.

[jandrese]

Even if you think the Blockchain itself is valuable, the "proof of work" is almost entirely wasted in the end. Some trillions of hash computations are thrown away for each one that is used.

[motohagiography]

Even as a blockchain non-fan, those computations are necessary to produce the desirable thing, and the same could be said for protein folding. There are a lot of great and devastating criticisms of blockchains, but the environmental concern is more of a proxy or even dogwhistle for a general political objection to cryptocurrencies - even reasonable objections in the context of their worldview. Greenwashing those objections seems like a canard.

[squeaky-clean]

I think you two are disagreeing on what "the desirable thing" means. You're saying it's creating the bitcoin/blockchain which is the desirable result. But they're saying that "desirable result" here is actually just computing a SHA-256 below a certain threshold. Sure you get the blockchain as a result, but does it really need to be SHA-256? As long as you have a "hash" function with a statistically predictable amount of CPU usage to generate a "successful" result, that function could maybe be something more meaningful. I have no idea if you could quantify protein folding into some sort of statistically predictable successful/unsuccessful CPU process.

[SubiculumCode]

Proof of Stake is taking over, in Ethereal, Polygon, and other alt coins.