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Proof of Work Without All the Work
- ForHackernews 9y agoWould this make it possible to implement a cryptocurrency that wasn't an ecological disaster?
- tomfitz 9y agohttps://en.wikipedia.org/wiki/Stellar_(payment_network) https://en.wikipedia.org/wiki/Stellar_(payment_network) is a decentralized currency that already isn't the "ecological disaster" that Bitcoin is.
- kronos29296 9y agoprobably not.
- kristofferR 9y agoEthereum is planning to switch to Proof of Stake in the coming years: https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ
- vanderZwan 9y agoI know this place is crawling with cryptocurrency fanboys, but this is a serious issue for many sceptics. Regardless of whether you think that criticism is valid, downvoting anyone who asks questions about how to address this does not help make their scepticism go away.
- jack_pp 9y agoThere's ecological disaster regardless of mining, I haven't done any math on the issue but I believe mining waste is a very small part of the overall polution in the world. We must develop technology to clean our planet regardless of mining waste. Given this and the fact that energy is becoming cleaner by the year I think worrying about mining waste is not rational
- vanderZwan 9y ago> I haven't done any math on the issue but I believe This is not the kind of discussion where assertion by belief has any place, on either side of the discussion. What we need solid estimates of how this technology currently scales, how it might improve, and how it compares to existing electronic currency, and physical cash (taking into account things like embodied energy of coins).
- bmcusick 9y agoBitcoin mines are in western China and Oregon precisely for the abundant and cheap hydro power. That's not so bad, ecologically speaking. Bitcoin is only as ecologically harmful as the source of the electricity used to run the miners, and it's no more harmful than any other use of electricity. If the world switches over to solar and wind as baseload power, problem solved. If the world doesn't switch away from using coal, that's not Bitcoin's fault. It's not a problem Bitcoin can solve.
- the8472 9y agoIf the world's economies ran on bitcoin we would need a stupendous amount of energy to keep the miners running. That energy not being spent on something else is a huge opportunity cost since many problems could be solved if there were just enough spare energy..
- bmcusick 9y ago> If the world's economies ran on bitcoin we would need a stupendous amount of energy to keep the miners running. You've misunderstood something about Bitcoin if you think this is true. Bitcoin miners use resources based on the logic of competing with each other for the value of the mining reward, not based on the number of transactions they process. If Bitcoin solved all its scaling problems so that everyone in the world could use Bitcoin, but mining rewards remained constant, the resources the miners expend to collect the reward wouldn't be any different from today.
- Nursie 9y agoI think you're underestimating the issue with attackers, if the world ran on bitcoin, attacking it becomes much more attractive, so use must indeed use more energy. It must use enough to make attacking bitcoin very unattractive.
- bmcusick 9y agoNo, sorry, that's not how Bitcoin works either. If the whole world used Bitcoin and the market cap of Bitcoin was over a trillion dollars, a 51% attacker could still only double-spend its own transactions. As long a public key crypto is secure, you cannot just re-write arbitrary Bitcoin balances into your own wallet even if you had 100% of the mining power. Therefore the incentive to attack Bitcoin is only as big as your own Bitcoin holdings, not the value of the entire market cap.
- deleted 9y ago[deleted]
- mtrycz 9y agoThere's more than one Proof of Stake cryptocurrency, and Ethereum does want to go PoS sometime. PoS have been around for 3 (maybe 4?) years by now. Proof of Stake is quite genius in the politics of it, and the power needed to run is minimal (you still need to keep your hardware powered on)
- GordonS 9y agoCan you give a short summary of how PoS works?
- lloyd-christmas 9y agoNot a personal summary, but this is Ethereum's FAQ: https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ https://github.com/ethereum/wiki/wiki/Proof-of-Stake-FAQ
- GordonS 9y agoSo... the more Ether you lock up, the more Ether you stand to gain; sort of like having a higher chance of winning the lottery if you buy a lot of tickets?
- clarkmoody 9y agoFirst, please show that cryptocurrency is an ecological "disaster" is the first place. Next, please explain how crypto is more of a disaster than the existing monetary system. Does the cryptocurrency mining economy pose more of an ecological threat than the system put in place to secure government fiat money: buildings, employees, vaults, mints, printing presses, armored vehicles, police, (some part of) the military, etc?
- antocv 9y agoByteball is such a cryptocurrency. There is no Proof-of-Work, or Proof-of-Stake.
- chj 9y ago“Consequently, if the network is attacked, our scheme guarantees security, with algorithmic costs that are commensurate with the cost of the attacker. Conversely, in the absence of attack, algorithmic costs are small.” Hope it works.
- empath75 9y agoThe network will be under attack constantly.
- KirinDave 9y agoBlockchain tech has a lot of potential uses outside of currency. In those fields, the likelihood of a constant foreverwar amongst the contributors is way lower. Also, providing a sliding cost on the network might make the miners agree it's more cost effective to step back from this breakneck energy-use-maximization game they're playing.
- falcolas 9y agoWell, in theory, you could simply alter the number of 0's required for any particular proof. Under attack? More 0's required in the hash. Not under attack? No 0's required. Determining if you're under attack would seem to be the harder part.
- ubaltaci 9y agoFor those who interested in the topic. Nem uses something called proof of importance https://www.nem.io/NEM_techRef.pdf https://www.nem.io/NEM_techRef.pdf
- tromp 9y agoIf new coins are distributed as block rewards, then collectively, miners will spend (nearly) the monetary value of those coins in competition to solve as many blocks as possible. In other words, any gains in marketcap will translate to increased mining efforts. Paul Sztorc has written a lot more about this in http://www.truthcoin.info/blog/pow-cheapest/ http://www.truthcoin.info/blog/pow-cheapest/
- qznc 9y agoIf a cryptocurrency becomes too big to fail, then it seems inevitable that nation-states and large corporations will mine it at a loss.
- russdpale 9y agoIf it is solar powered, I don't see how it will be mined at a loss? Power is the number one cost, and we have a free unlimited supply of it.
- jacobush 9y agoSounds like the paperclip machine.
- jeremyjh 9y agoTell us more about your solar power station that has no capital investment or operating cost.
- cryptonector 9y ago"opportunity cost"
- tylersmith 9y agoPoW wouldn't work if power was free or unlimited.
- tempay 9y agoIt would, just the hardware/admin/maintenance costs would dominate instead.
- kanzure 9y agoHere's some "lore" around proof-of-work and why it must burn external resources: https://download.wpsoftware.net/bitcoin/asic-faq.pdf https://download.wpsoftware.net/bitcoin/asic-faq.pdf https://download.wpsoftware.net/bitcoin/pos.pdf https://download.wpsoftware.net/bitcoin/pos.pdf https://download.wpsoftware.net/bitcoin/alts.pdf https://download.wpsoftware.net/bitcoin/alts.pdf
- csomar 9y agoSo now we have click-baity academic papers? Can someone summarizes to me the genius behind the idea? Because as far as my math goes, it is not theoretically possible.
- geofft 9y ago> So now we have click-baity academic papers? As academic paper titles go this is pretty normal. > Can someone summarizes to me the genius behind the idea? I'm reading quickly, but I think the idea is that the reason we need proof-of-work is to prevent Sybil attacks, that is, a single entity pretending to be 50% of the network via spoofed identities. So you have a concept of persistent identity for each (apparent) member of the network, and you require nodes to solve a computational problem when they join the network and also periodically while they're in the network. This puts relatively little computational load on each participant, but puts a lot of load on a long-term attacker, and even more work on a short-term attacker who's trying to claim a bunch of identities in a hurry. I'm not sure how much this actually helps Bitcoin, since my impression is that the computational load is what's needed to match the abilities of the legitimate members of the network. I guess the trick is that maybe you can make the block-mining difficulty scale up less aggressively over time, but I'm not following that logic yet.
- geofft 9y agoThinking harder I guess the only reason that mining difficulty is so competitive is that there's a reward for mining, given to just the miner, so the arms race is profitable (much as, say, the arms race for microsecond-level tech improvements is profitable to HFT because even if two algorithms make the same decision only one gets the purchase in first). So if you get rid of that, and maybe add a nominal "reward" for solving the puzzles to remain in the network and give it to all participants, the incentive to build giant mining farms goes away: the only reason to have additional computational power is either to keep up with the network as a whole (not the fastest person in the network) or to actually gain 50% of computational power.
- russdpale 9y agoWhen I read this: "This shortcoming is highlighted by recent studies showing that PoW is highly inefficient with respect to operating cost and ecological footprint." The moment we try and do away with this inefficiency we are going against the entire solution of what bitcoin was going for: how to use all of the inefficient computer parts laying around the globe for something useful? It makes me think people just don't get it. High inefficiency is the _ENTIRE_ point! It gives rarity to the coin. That 10 minute block time is the same as compressing millions of years of geology into 600 seconds. It is fundamentally sound mathematics, and ultimately, that is why it holds its value. It is not meaningless mathematics, people who say that don't understand fully as to what they are talking about, imho.
- ricardobeat 9y ago> how to use all of the inefficient computer parts laying around the globe for something useful? How do you reconcile this statement with the fact that mining is done by a few thousand entities in the whole world, using custom-built hardware?
- wlesieutre 9y agoYou're misinterpreting what people mean by "inefficient" in this context. The bitcoin mining ASICs are extremely efficient at mining bitcoins. You can't mine them with an old GPU and expect to make back more money than you spent on electricity. But the choice to mine bitcoins at all is (arguably) an inefficient use of resources that could have been used for pretty much anything else. There's no shortage of useful problems to be worked on by supercomputers and the world would be better off if we did that instead of mining cryptocurrencies. But the economic incentives aren't there. EDIT: Reading your comment again, I think I was a bit quick on the "you're wrong" here. ISo to clarify, I do agree that inefficiency is at the core of the bitcoin mining ecosystem, but it's all about the "we have to spend a bunch of energy that could've done a lot of other things" inefficiency, not an individual "we can use old hardware for this" sort.
- Nursie 9y agoWhen you look at it from that angle, Bitcoin becomes a very interesting hack on economic incentives (and how they don't always map to useful real-world activity)
- nullc 9y agoI think the title and abstract of this are not very clear. I gave it a fast skim to figure out what general class of thing it actually is. This should be compared with "proof of idle" (https://www.cs.virginia.edu/~shelat/14s-pet/2014/02/11/proof-of-idle.html https://www.cs.virginia.edu/~shelat/14s-pet/2014/02/11/proof...). It is an online scheme for resisting sybil attacks in a P2P network where nodes have cryptographic identities which works by periodically forcing all users to do proof of work within a limited time window. Peers that don't respond fast enough are banned from the system (have to create a new identity to join, which is computationally expensive). The idea is that this get some of the benefits of POW for sybil resistance without spending as much energy. It doesn't, however, produce a large amount of cumulative work building up over a history. So it's not the sort of thing you'd want to use to protect the history of a ledger directly.
- SkyMarshal 9y agoOne of the holy grails in cryptocurrency research is figuring out a PoW alternative the provides similar security at reduced energy cost. A few other examples: 1. Bram Cohen's Proof of Space & Time: https://youtu.be/aYG0NxoG7yw; https://youtu.be/aYG0NxoG7yw; https://cyber.stanford.edu/sites/default/files/bramcohen.pdf https://cyber.stanford.edu/sites/default/files/bramcohen.pdf 2. DFINITY VRF-based Threshold Relay: https://youtu.be/o8HHM18PedU https://youtu.be/o8HHM18PedU (https://en.wikipedia.org/wiki/Verifiable_random_function https://en.wikipedia.org/wiki/Verifiable_random_function) 3. Algorand: https://people.csail.mit.edu/nickolai/papers/gilad-algorand-eprint.pdf https://people.csail.mit.edu/nickolai/papers/gilad-algorand-... These are some of the more interesting ones, but plenty of others.
- empath75 9y agoSo let's say you replace hashing with some algo that just requires a lot of memory. Wouldn't the cost just be sunk into buying a lot of ram and 'wasting' it? Ram isn't free to produce and has its own externalities.
- colordrops 9y ago
- chairmanwow 9y agoThere is something thoroughly logical about this approach to the unfortunate waste implicit in Proof of Work (PoW) schemes. In summary of the motivations of the paper: PoW is currently limited to cryptocurrencies as a security system because of the implicit financial incentive in mining coins. This approach could allow PoW schemes to be widely adopted to secure systems as the overhead is lowered dramatically. Additionally, battery powered devices (ie phones) could make use of PoW without incurring large battery drains. This last bit is particularly interesting and could allow some interesting, distributed P2P systems on cellphones to arise. The general principle of the paper revolves around asking network members to prove computational power only as much as necessary as the network scales. Because an attacker could easily spoof their MAC / IP address when joining the network, computational tests are periodically distributed to network members. If the test is unsolved in an allotted time period, their network membership is revoked (and the node is blacklisted). The attack referred to in the paper is an attacker adding bad (fake or otherwise) nodes to a system rapidly.
- alistproducer2 9y agoI'm in the process of auditing new low-power Po* algos for a crypto system I'm researching. This paper needs a way better abstract. The math is incomprehensible without knowing what it's end goal is. The paper uses acronyms (ex "Good ID") before explaining what they are. Overall a poorly written paper. The work maybe revolutionary, but what good is that if it's so difficult to understand. People forget that the purpose of a paper is to communicate your idea to other people. If it doesn't do that effectively then no matter how awesome the work is, you've failed.