PoS has already been disproved and is a disaster. The nothing at stake problem was never fixed, it is always a bigger risk than a 51%+ attack on PoW. PoS will be the nail in the coffin for Ethereum after they go full PoS, we will see that in the next years. There is nothing better than PoW, Satoshi predicted it.
From the Endless Bullshit I hear about Nothing at Stake Lie, here are my responses to both scenarios .Some authors[15][16] argue that proof-of-stake is not an ideal option for a distributed consensus protocol. One problem is usually called the "nothing at stake" problem, where (in the case of a consensus failure) block-generators have nothing to lose by voting for multiple blockchain-histories, which prevents the consensus from ever resolving. Because there is little cost in working on several chains (unlike in proof-of-work systems), anyone can abuse this problem to attempt to double-spend (in case of blockchain reorganization) "for free".[17]
Ok , above is the quote from the wiki.
Here is what is wrong with it.
BadGuy has 50 coins , GoodGuy1 has 10 Coin , GoodGuy2 also staking 10 coins
GoodGuy1 is staking
[
10] on the block 500 on Fork1
At the same moment another block is created by GoodGuy2
[
10] on the block 500 on Fork2
Now the BadGuy
Since he has nothing to Lose , Stakes his 50 Coins on both Forks
So Now
Fork1 [
60] & Fork2 [
60]
Which means by trying to stake on both blocks at the Same Time, all he did was
Negate his Staking Power by adding to Both.
Which Fork is chosen will be decided by someone else , not trying to play both sides.
He makes his staking power irrelevant.
The other flaw with the Nothing at Stake Lie, which must be beyond the concept of PoW miners.
When Proof of Stake stakes a Block , Coin Age is used up, meaning those coins will now be offline and unable to stake until their minimum stake age is reached again.
It would be the same as when a PoW miner mined a coin and then immediately turned off his ASICS for a prescribed amount of time.
Which would mean he could mine no other block until , he was allowed to turn his ASICS back on.
Which is why PoS is superior to PoW , as random Chaos is entered into it.
PoW miners can maintain the ~ same HashRate thruout mining while a PoS Staker Amounts & Coin Age are in constant Flux every time they stake.
So what is burned when you stake, Coin Age & Staking Weight is burned, and it takes a minimum stake age before it can be recovered.
FYI:
As far as the DoubleSpend , PoW or PoS is susceptible to doublespend with Zero Confirmations .
Solutions for both PoW & PoS is to wait the prescribed amount of Confirmations, and never accept Zero Confirmations.
In nothing at stake attack, as I understand, attackers doesn't stake on both forks. They argue that stable strategy for all honest miners is to mine on all the fork. Then attacker assumes that everyone is doing this and stakes on the double spend fork (or whatever he wants to use instead of main-chain). That is why it doesn't matter how much attacker has. I do find this valid objection, just something not fundamental and trivial to prevent, hence I started this thread.
OK , so you think
Attacker has 1 coin , GoodGuy1 has 10 coins GoodGuy2 also staking 10 coins
Fork1
GoodGuy1 is staking
GoodGuy2 is staking
[20]
At the same moment on Fork2
GoodGuy1 is staking
GoodGuy2 is staking
[20]
Now the Attacker
Places a transaction on Fork1
Stakes his 1 coin on Fork 2
So Now
Fork1 [20] only 2 blocks & Fork2 [
21] 3 blocks
Fork2 now has more coins in 3 Blocks, and becomes the longest chain with the most difficulty.
All of this in an attempt at a double spend.
1st off
Standard PoS wallets don't Multi-stake, you would have to code one your self.
Let's say you do and it works exactly as you described and you spend coins on Fork1 and overwrote it when Fork2 became the longest Chain.
Basically a History rewrite.
This is why it will Fail. Once the fork2 becomes the longest chain, all of the wallets will reorg to fork2 and it will be the correct chain.
This means the coins you sent in the transaction on fork1 will not confirm, and the wallet you sent it too will not reach even 1 confirmation.
Longest chain with the most difficulty wins , just wait the recommend # of confirmations and all zero confirmation attacks fail.
FYI:
Double spending if someone accepts zero confirmations is easy on Proof of Work.I don't even need to be a miner, just paid a higher transaction fee to pull it off.I had 2 devices with the same BTC wallet , send the coins from the 1st device to the vendor with no fee,
then send all of my BTC from the same wallet on 2nd device to another BTC address I control, including a high fee for faster transactions.
If the Vendor accepts Zero confirmations, he will see the BTC sent from the 1st device, and I exit the store with his product for free.
5 to 10 minutes later after the 1 confirmation, all of my BTC will have arrived at my other BTC address and the Vendor just saw his payment never Confirmed.
Moral is PoW or PoS wait the recommend confirmations.
FYI:
BTC has lost the 51% PoW battle with the Chinese Miners for over a year, funny no one worries about that. FYI2:
BTC has an average of 1.3 orphans per day of 144 blocks, meaning if I really got lucky,
there is one opportunity everyday to run a double spend on BTC and actually get 1 confirmation before it reorgs.
Chinese mining pools using a 51% attack could overwrite the last 72 blocks if they felt like it.
