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Gridcoin: An open-source cryptocurrency that rewards volunteer computing

gridcoin.us

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Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#71

Post by algo646464 »

VMG wrote: post #55
algo646464 wrote: post #52

Earlier quoted context omitted.

The external reward in "useful" PoW is given to all miners, good and bad. So everyone is equally incentivized. In fact it should actually increase the participation in the network, e.g. those who don't care about cryptocurrency but are interested in the "useful" problem being solved. The external reward by itself provides no competitive advantage. It reduces everyone's costs by the same amount. Rewriting history stil…

Rewriting history needs to be expensive, not just difficult. If you decrease the cost of writing history, you decrease the penalty of participating in a minority chain.

I always understood the security of block-chains as a race between the good and the bad agents.

Both are extending their respective chains as fast as they can. A bad-agent, who wishes to double-spend has to rewrite history, and therefore has to start a few step behind the good agent. To succeed, the bad agent has to overtake the good agent.

Even if both have the same speed (i.e. 50% computational power each), the good agent will sill be a few steps ahead of the bad agent, and the system is secure. If the bad agent is faster(51%), then eventually it will overtake the good agent breaking security.

This is true even if the cost of computation is zero (e.g. the Govt. pays for all your computation cost). As long as the bad agent doesn't have 51% or more of the computational power, the system is secure.

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#72

Post by Moodles »

jl2718 wrote: post #14

This may be misunderstanding the function of PoW. Bitcoin PoW provides three things: selection, security, and incentive. The compute resource burn is an externality, although, it also ends up providing an important function, economic distribution. For PoW to work,it has to be hard to produce, easy to verify, and most importantly, attest to one and only one state of the blockchain. The last part is where this fails as…

I once saw another example coin like this where the "useful PoW" was finding chains of prime numbers or something. However, PoW solutions were not dependent on the current blockchain sate, which rendered it insecure as someone could just stockpile solutions and then hijack the blockchain. Is it the case here too?

The closest I've seen to a useful PoW coin is one which relied in intel SGX to prove that the work done was useful and honest, but of course the central root of trust is really Intel's SGX in that case.

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#73

Post by jl2718 »

Robotbeat wrote: post #31
wyldfire wrote: post #26

For most cryptocoins, you want a proof-of-work to be: (1) easy for a computer to verify, (2) hard for a computer to perform, (3) impossible to predict for a given 'block' and (4) decentralized and untrusted. If it's a novel scientific problem it won't be all of these. An interesting exception is prime numbers. Primecoin [1] has a useful proof-of-work: it finds Cunningham chains of primes. If you don't like the energy…

Folding can be verified easier than it can be produced.

I spoke briefly with Vijay Pande about this in 2011. Folding does have a lot of the right properties for a good proof-of-work system, the main exception being that the solution must be unique to the input. It may be possible to achieve this by embedding information into sets of constraints, as long as any particular set of constraints can be shown to be isoenergetic. Or perhaps by expanding the problem by adding more atoms in a way that embeds information about the inputs. Also, the solutions would be quite large. But I think he was more interested with my experience writing molecular dynamics code than blockchain, and rescinded the RA offer after this conversation, so I haven’t thought about it much since then.

Reconsidering (briefly) now, I think it can be done.

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#74

Post by noxer »

deeeeplearning wrote: post #67
noxer wrote: post #62

Earlier quoted context omitted.

Whats the use for the coin? Its an incentive obviously but its only so because it has a price tag. Who should buy the coin from me if I "mined" one and what would he do with it?

>Whats the use for the coin? Its an incentive obviously but its only so because it has a price tag. Who should buy the coin from me if I "mined" one and what would he do with it? This is the same for any crypto coin. Certainly not unique to Gridcoin.

That doesn't answer the question.

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#75

Post by beiller »

mikepurvis wrote: post #17
keymone wrote: post #9

Earlier quoted context omitted.

Your aim is off, bitcoin using energy is fine just like any other use of energy is fine, part of the free market of ebergy. It’s production of energy from fossil fuels that isn’t fine.

I don't think that's really true. There are plenty of cases where we can decide collectively as a society that a thing is valuable or not-valuable and intentionally set a particular price for it. As an obvious example, no one would argue that hospitals in Texas should have been paying the "market rate" for electricity last week, and conversely, it would have been a scandal if someone had been mining bitcoin on the Te…

> turning electricity into heat in the form of bitcoin mining is a gigantic and unacceptable waste of a resource that we'd like to use for other things

Hi I live in a cold place! Interestingly, bitcoin mining is an electric space heater with 100% efficiency. I could theoretically heat my home. Currently I use natural gas (which emits CO2 aka a greenhouse gas). The furnace runs at 95% efficiency I think. If my electricity can be generated with less CO2 emissions than my furnace via nuclear, solar, wind, then it would be quite desirable wouldn't it? Would it be fair to say electric heaters are a giant unacceptable waste of compute?

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#76

Post by Moodles »

DavidHilbert wrote: post #61
jl2718 wrote: post #14

This may be misunderstanding the function of PoW. Bitcoin PoW provides three things: selection, security, and incentive. The compute resource burn is an externality, although, it also ends up providing an important function, economic distribution. For PoW to work,it has to be hard to produce, easy to verify, and most importantly, attest to one and only one state of the blockchain. The last part is where this fails as…

> The solution to a puzzle is meaningless if the same solution can be shown as the result of two different inputs. This isn't true. There are an infinite number of inputs that result in the same solution for bitcoin (or any hash)

Right, but that's a little unfair? SHA-256 is literally a function designed to make it impossible to find such collisions. BIONIC problems aren't designed with that in mind.

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#77

Post by roboticmind »

noxer wrote: post #62
roboticmind wrote: post #53

For those that are wondering how this works, Gridcoin uses PoS - not PoW - and then rewards for research on top of it. It is not locked into any algorithm because it's not PoW. There are currently 18 different BOINC project [1] that it rewards. New projects can be voted in or can be voted off. To try to reduce the centralization, there is a system of oracles that gathers the stats from each project and the nodes veri…

Whats the use for the coin? Its an incentive obviously but its only so because it has a price tag. Who should buy the coin from me if I "mined" one and what would he do with it?

As one of the commenters mention, it's an issue with all cryptocurrencies. Right now one of the reason people want to get Gridcoin is to get enough to stake regularly to earn their rewards or because they believe in the coin. In the future, there's been some ideas floating around that I think are very interesting. For instance, one idea that's been floating around is to create a service that accepts GRC and offers assistance to researchers for setting up a BOINC project

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#78

Post by [deleted] »

algo646464 wrote: post #47
VMG wrote: post #32

Proof-of-Work only makes sense if there is an opportunity cost for mining an invalid chain. If mining an invalid chain is "useful" in some way, the security guarantee disappears.

Can you explain why the security guarantee disappears in more detail? I thought that the security of a block-chain comes primarily from the difficulty of rewriting the chain of blocks. To do that you will have to fork and recompute the chain from some point back in history (say 5 blocks ago). This puts at a disadvantage since the rest of the network is ahead of you by 5 blocks and will continue adding new blocks. So…

[deleted]

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#79

Post by fallingknife »

VMG wrote: post #50
algo646464 wrote: post #47

Earlier quoted context omitted.

Can you explain why the security guarantee disappears in more detail? I thought that the security of a block-chain comes primarily from the difficulty of rewriting the chain of blocks. To do that you will have to fork and recompute the chain from some point back in history (say 5 blocks ago). This puts at a disadvantage since the rest of the network is ahead of you by 5 blocks and will continue adding new blocks. So…

You don't actually need 51% of the mining power to perform a double-spend attack. Just by pure chance, even with 10% of the mining power, you will find 5 blocks in a row sometimes. With a "wasteful" PoW, miners would not attempt this as they would hemorrhage money doing that. Withe a "useful" PoW, miners could have an outside funding source like some institute that pays for protein folding. The would not lose money i…

If you had 10% of the network the odds of that would be only 1/100K right? Or is that not how this works?

Re: Gridcoin: An open-source cryptocurrency that rewards volunteer computing

#80

Post by neolefty »

jl2718 wrote: post #68
powerbutton65 wrote: post #65

Earlier quoted context omitted.

Like it or not they are technically correct. SHA-256 is a one way compression and furthermore the PoW for bitcoin doesn't require a match for the entire hash. There's loads of examples of this in the bitcoin network whenever there's been a fork and eventually orphaned blocks.

Those are different solutions to the puzzle. Nobody has ever published a sha-256 hash collision. It has happened once with sha-1.

The principles are the same — it's just harder to find collisions for larger digest sizes. (Although bugs in sha-1 add an interesting wrinkle to the discussion.)

In fact one could argue that encryption without requiring infinite bandwidth or computation requires finite difficulty in math puzzles.

So our current approach to encryption is fundamentally vulnerable to (vastly) more powerful adversary computers. Only things like quantum cryptography break free of that limitation, by changing the ground rules.

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