Why isn't proof of stake more widely supported?

[cunicula]

To make an informed decision, read about proof-of-stake in the wiki [ https://en.bitcoin.it/wiki/Proof_of_Stake ] and also read the threads on tragedy of the commons and proof of stake in the forums.

Feel free to post your own explanation for your views.

[MoonShadow]

Proof-of-stake is a flawed voting mechanism for bitcoin or an alt-coin.  It would, at a minimum, require associations between the addresses within a major stake claim; breaking many types of anoniminty that existed prior to the claim of stake.

[MoonShadow]

Proof of stake already exists. Anyone with a significant amount of Bitcoins has plenty of incentive to maintain the network.

Indeed, this is already true without the proof part.

[cunicula]

  It would, at a minimum, require associations between the addresses within a major stake claim; breaking many types of anoniminty that existed prior to the claim of stake.

Currently, miners currently reveal ip adresses and where their coins are sent, but these can be disguised via TOR or VPN. Miners can maintain multiple mining accounts that don't appear related to one another, without any loss in mining efficiency.  This would all still hold under proof of stake. The ability to maintain apparently independent accounts without penalty is implied by constant returns to scale. There is no difference with respect to anonymity under the two systems.

It would be more constructive if you could provide a logical argument supporting your view or a link to a logical argument. Logical arguments can be shown to be true or false. Blind assertions which are not pinned on logic could potentially confuse people.

[cunicula]

Proof of stake already exists. Anyone with a significant amount of Bitcoins has plenty of incentive to maintain the network.

I suggest you read the tragedy of the commons threads [https://bitcointalk.org/index.php?topic=67900.0, https://bitcointalk.org/index.php?topic=6284.0, http://bitcoin.stackexchange.com/questions/3111/will-bitcoin-suffer-from-a-mining-tragedy-of-the-commons-when-mining-fees-drop-t, https://en.bitcoin.it/wiki/Tragedy_of_the_Commons. These threads contain extensive discussions of these issues and indicate why incentives to maintain the network are exceedingly weak.

[MoonShadow]

And the current proof-of-work system isn't a tragedy of the commons, it's actually the reverse of same.  I was thinking along these lines early on, and made some of those same very arguments about a year ago, but I accept my error now.  A tragedy of the commons requires that a common resource be consumed by self interested players, but what is really happening is that a common resource (the security of the blockchain) is actually being aggregated.  I've made many counter arguments to my prior position on this since then, particularly centered around the incentive for major future entities in competition investing in exclusive mining agreements.  Think Wal-Mart & McDonalds agreeing to partner on a mining center that makes every effort to exclude the transactions intended for the Target & Burger King alliance.  I.E., companies in different industries have an incentive to work together, but exclude their competitors, as far as that is realistic in order to avoid transaction fees & processing delays.  This adversarial situation benefits the bitcoin consumers collectively, regardless of how each set of mining alliances should treat each other.

Brick & Morter banks would have similar reciprocal processing agreements; in order to get the other bank to process their customers' transactions without a fee & relatively fast, they would have to do the same for their customers.  Such an agreement would benefit both banking institutions, regardless of their relative size.  For example, MEGABitCoinBAnk in NYC has 100,000 customers and a 1000 GPU data center, while LittleFarmersBitcoinTrust near Cincinnati only has 10,000 customers and a 50 gpu data center.  Both banking institutions stand to benefit to some degree, so long as they are not competing in the same local markets, so the agreement happens.  MEGABitCoinBAnk is likely to make dozens of such agreements, leveraging the gpus of those dozens of local banks, even if some of them do compete with each other in the same market.

[FreeMoney]

Currently, miners currently reveal ip adresses and where their coins are sent, but these can be disguised via TOR or VPN.

Care to elaborate?

[MoonShadow]

  It would, at a minimum, require associations between the addresses within a major stake claim; breaking many types of anoniminty that existed prior to the claim of stake.

Currently, miners currently reveal ip adresses and where their coins are sent, but these can be disguised via TOR or VPN.

This is not a requirement with proof-of-work, merely a convience for pool mining.

 There is no difference with respect to anonymity under the two systems.

There is, but I'm not willing to argue that point.  It's secondary really, anyway.

It would be more constructive if you could provide a logical argument supporting your view or a link to a logical argument. Logical arguments can be shown to be true or false. Blind assertions which are not pinned on logic could potentially confuse people.

Speak for yourself.

Anyway, I've made these kind of arguments many times over the past two years, quite literally on both sides of this issue.  What it all comes down to is that PoS doesn't offer an advantage over PoW, but attempts to solve a presumed future problem that I (no longer) agree exists.  I also do see potential problems in it's practical implementations, although those may not be insurmountable.  However, the very biggest problem with PoS is that a major entity could literally come in and buy it out and become a new central bank, as the requirement for having more than the processing power of the whole of the honest network no longer applies to a PoS miner with a large enough of a stake.  Your not going to solve a problem here.

[cunicula]

Currently, miners currently reveal ip adresses and where their coins are sent, but these can be disguised via TOR or VPN.

Care to elaborate?

About what exactly? http://blockchain.info/ provides data about ip's that relay blocks. In some cases it was done by a pool. In other cases by a private ip. If the relayer was a pool, then the pool in turn knows the ip adresses that was used to connect to it. The pool operates just like a vpn in this case.

[MoonShadow]

Currently, miners currently reveal ip adresses and where their coins are sent, but these can be disguised via TOR or VPN.

Care to elaborate?

He's talking about pool miners.

[markm]

If coinbase transactions take 120 blocks, lets say, for their outputs to mature, then the first miner won't start being able to put in any stake for the first 120 blocks. Then, however, they can put the full number of coins minted per block in as stake on each of the next 120 blocks.

Basically each stakeholder will only be able to put 1/120th of their stake into each block if they manage to mine 120 blocks in a row.

If someone else gets a block sometime within those 120 blocks, that frees up an extra full block's worth of minted coins to use to increase your stake going forward, but it means there is someone else out there now who can put a full block's worth of coins into the next block they mine. Then 120 blocks after they manage to mine a second block, they'll have twice that amount they can put in.

I suspect it will get very hard very fast for new miners to enter the mining biz with any chance of actually making a go of it.

So it seems likely to degenerate very very fast into a "final outcome" whether that final outcome is Cunicula's (1), monopoly, or his (2), Oligopoly, or his (3), perfect competition. (Of which number three seems very unlikely to me in this scenario.)

-MarkM-

P.S. Maybe not starting PoS until many blocks in, or phasing it in slowly by having it only count fractionally, like multiplied by min(10000/blockheight,1) or something, could help some but maybe not really much. (And if not much then little point adding it to bitcoin either...)

[cunicula]

If coinbase transactions take 120 blocks, lets say, for their outputs to mature, then the first miner won't start being able to put in any stake for the first 120 blocks. Then, however, they can put the full number of coins minted per block in as stake on each of the next 120 blocks.

Basically each stakeholder will only be able to put 1/120th of their stake into each block if they manage to mine 120 blocks in a row.

If someone else gets a block sometime within those 120 blocks, that frees up an extra full block's worth of minted coins to use to increase your stake going forward, but it means there is someone else out there now who can put a full block's worth of coins into the next block they mine. Then 120 blocks after they manage to mine a second block, they'll have twice that amount they can put in.

I suspect it will get very hard very fast for new miners to enter the mining biz with any chance of actually making a go of it.

So it seems likely to degenerate very very fast into a "final outcome" whether that final outcome is Cunicula's (1), monopoly, or his (2), Oligopoly, or his (3), perfect competition. (Of which number three seems very unlikely to me in this scenario.)

-MarkM-

This is true. The initial miners can reinvest mining profits and obtain a larger and larger share of mining power over time. However, this is also true under the current system. Both systems allow free entry provided that markets for mining inputs are competitive. Just like people purchase GPUs to enter mining now, they would purchase coin to enter mining. The issue you are worried about is that a competitive exchange market may fail to arise, thus limiting entry. However, the initial miners have extremely strong reasons to fund the establishment of a competitive exchange market. The currency won't have any exchange value whatsoever in the absence of such a competitive exchange market. Control over a large volume of coin that is not exchangeable is not profitable.

[markm]

Maybe we can also start with initial investors, so that 100 people or more all buy in before launch.

The genesis block could have one huge multi-output coinbase transaction in it, issuing coins to the initial stakeholders...

-MarkM-

I still think though that it will be too easy to take over. Look at how large Deepbit always tended to be, from people giving up some of their profit in return for regular payments. I think something like that will happen, with more and mroe of the total nubmer of coins being tied up in that large pool as stake, until maybe only 1/121th of the total coins in existence are circulating, the other 120/121 of them being permanently tied up in maintaining an unbreakable monopoly.

It probably won't actually need 120/121 of the total coins, maybe q mere 51% of all coins will suffice, in which case it will be even easier.

But the more coins permanently tied up, the more the few in circulation should go up in price due to "rarity" maybe? unless just knowing that one pool controls the majority of the coins causes people to flock to yet another different cryprocurrency, one that is not controlled my some monopoly.

In fact the answer every time to monopoly might be simply to make another altcoin. The big players might ignore some of them as too puny to worry about of something, of they could keep quiet, growing across freenet and i2p and Tor, an underground grass roots person to person currency instead of a widely publicised scheme like bitcoin seems to prefer to be.

[kjj]

Anyway, I've made these kind of arguments many times over the past two years, quite literally on both sides of this issue.  What it all comes down to is that PoS doesn't offer an advantage over PoW, but attempts to solve a presumed future problem that I (no longer) agree exists.  I also do see potential problems in it's practical implementations, although those may not be insurmountable.  However, the very biggest problem with PoS is that a major entity could literally come in and buy it out and become a new central bank, as the requirement for having more than the processing power of the whole of the honest network no longer applies to a PoS miner with a large enough of a stake.  Your not going to solve a problem here.

Just in case anyone missed it.

[Etlase2]

how can you possibly make this thread when you made the wiki page like 2 days ago? jump the gun much?

[cunicula]

Anyway, I've made these kind of arguments many times over the past two years, quite literally on both sides of this issue.  What it all comes down to is that PoS doesn't offer an advantage over PoW, but attempts to solve a presumed future problem that I (no longer) agree exists.  I also do see potential problems in it's practical implementations, although those may not be insurmountable.  However, the very biggest problem with PoS is that a major entity could literally come in and buy it out and become a new central bank, as the requirement for having more than the processing power of the whole of the honest network no longer applies to a PoS miner with a large enough of a stake.  Your not going to solve a problem here.

Just in case anyone missed it.

D&T did a good job debunking this here: https://bitcointalk.org/index.php?topic=68213.msg799136#msg799136
It is also discussed in the proof of stake wiki as the "Monopoly problem"

Main Point: A dominant investment gives you absolute control over either system.  PoS requires a much larger investment to obtain control, PoW requires a smaller investment.

If you have additional questions, I am happy to answer them.

[cunicula]

how can you possibly make this thread when you made the wiki page like 2 days ago? jump the gun much?

Anyone is free to contribute to the wiki. If you have some insights, then you can contribute yourself.

I like to keep track of opinions and keep putting information out there so people can make informed decisions.

A big problem is that very few people understand the issues clearly. That can only be resolved through continuing discussion and development of better online sources of information. These are complementary to one another.

[Etlase2]

yah and the issues are currently being discussed in the various other threads. didn't really need a new topic was my point.

[cunicula]

Understand that. But it is important to know whether the primary issue is disagreement in principle or whether people just disagree becomes they prefer the status quo. Apparently, several people (not me) prefer proof-of-stake in principle, but also have a dominant preference for maintenance of the status quo. I wasn't aware that this was an important reason for opposition to proof of stake.

[Etlase2]

well I still say proof-of-transaction-activity or whatever you want to call my idea is better in every way, and no chain fork