Topic: PoS is far inferior to PoW - why are so many people advocating switching to PoS - page 7. (Read 12865 times)

I agree. I have been touting Myriadcoin as one of the biggest innovations in the PoW cryptocurrency world. It is definitely a step forward. Unfortunately, it still doesn't change the fact that a lot of electricity and processing power is wasted in the process. Pretty much all scientists agree global warming is real and PoW only accelerates that. I see PoS or a variant of it as being the ideal solution for consensus mainly for this reason. Why increase emissions unnecessarily simply to reach decentralized consensus when it is not needed because PoS is sufficient at performing the same job? Also.. all of the processing power could actually be used to do something useful to society instead of simply securing a block chain, such as solving cancer or assisting other scientific research. Primecoin is a good example of a PoW algo that is actually useful to society.

These are my biggest concerns about PoW, not the centralization of it. All systems.. PoS and PoW.. inevitably tend towards centralization eventually. PoW tends towards centralization in mining pools and large farms setup with cheap power which utilize the economies of scale ASICs provide. PoS tends towards centralization with the need for check points to prevent certain attacks (or at least in the current variants of PoS.) DPoS works on the realization that all systems inevitably tend towards centralization, ad it gives you a way for stake holders to control that centralization. Stake holders choose who becomes a delegate, with PoW you cannot choose who secures the block chain.. whoever buys mining power can do it. This helps keep nefarious actors out. Also, you can vote in developers and people creating important core services for the coin as delegates to compensate them for doing so. Therefore, a DPoS coin can hire employees that work for the cryptocurrency... PoW can obviously only do this via donations. The use of only 101 delegates allows block times to be reduced to a little as 10 seconds and process many transactions a second.. something that is very hard to achieve (maybe impossible) with PoW. There are many benefits of DPoS over PoW in my mind which far outweigh the highly unlikely attack vectors, and that is why I support it over PoW alternatives.

I disagree again.

It is not waste, it is a conversion of energy value into coin value. PoS coins (various types as you mentioned) also use a method to get value into the coin itself:
- PoW stage: it's the same as a fully PoW coin, just that coin emission ends very quickly and is unfairly distributed with regards to future investors.
- gib muny: just "devs" ripping off investors and collecting pots of bitcoin (the irony) to give price decaying coins to them

There can be only one instance of proof when an exchange owns 51% of the supply, when all depositors account for all deposits in various known addresses and reach a 51% sum, otherwise it's not ensured that you can detect a 51% ownership.

Again, PoW attack vectors are valid for mere HOURS, while a PoS attack vector can be used FOREVER once it opens up. This is a very HUGE difference in the security model which reduces the effect of the attack.

Going back to the PoW "waste" which you pretty headed PoS supporters don't seem to understand not even 6 years after Bitcoin was invented. This is not "waste", it is a cost that is converted into new coins (scheduled or fees) from block rewards. The approximate cost to generate a block is found in the value of new tokens. This cost is real and significant, this gives value to Bitcoin.

The cost of generating PoS blocks is basically zero (5$ a month for electricity on donated hardware or a VPS bill). The value of the block rewards is thus zero, this gives no value to new PoS coins, the market cap remains the same, but new coins are added. Price per existing coin will be lower.

What does this mean? Let me show you:

PoW
Bitcoin: 0.7% price growth every day for 6 years, 5,678,828,589 USD market cap
Litecoin: oscilating but stable parity with Bitcoin for 3 years, 138,439,389 USD market cap
Namecoin: oscilating but stable parity with Bitcoin for 3 years, 10,064,647 USD market cap

Hybrid
Peercoin: oscilating but stable parity with Bitcoin for 2 years, 18,474,609 USD market cap
Novacoin: down the shitter in 2 years, 640,582 USD market cap
YACoin: down the shitter in 2 years, 37,320 USD market cap

PoS
I'll let you pick the best examples older than one year

Myriadcoin's multi-PoW framework helps with the decentralization of mining that some of you may be concerned about. More than you think, actually.

A lot of people (me including) use the term PoS as more of a broad term that includes all consensus algorithms that are not based on PoW. This includes many different variants of PoS... PoS as in Peercoin, transparent forging as in Nxt, DPoS as in Bitshares, etc, etc...

Many people would refer to Bitshares and Nxt as being PoS even though they are actually a variant of it. I agree it is confusing, but a term was needed to differentiate PoW coins from non-PoW coins and I think PoS is a natural choice since it was the first non-PoW consensus algo. As long as people realize that there are different variants of PoS, each functioning differently and with their own sets of pros and cons, then I don't see any issues with the terminology.

It is waste in that it wastes electricity and processing power unnecessarily as has been proven by PoS. This is something Bytemaster (Bitshares main dev) came up with, for the Bitshares community to refer to PoW as Proof Of Waste to point out the fact that it is unnecessary to expend these resources simply to secure a block chain, as is proven by PoS and all of its variants.

I will concede you have a point as to the pools only being able to mount an attack temporarily before everyone switches pools. However, I stick to the fact that you simply made up "as it happens for many coins an exchange owns more than 51% of the supply", and you have no proof of this and it is not true. The point was that there are different attack vectors for PoW that exist other than achieving 51% of the hash power. Both PoW and PoS variants have vulnerabilities and different pros and cons. There is no perfect solution, and I believe that PoW is often touted on these forums as being a perfect solution when in actuality it is not.

NxT hashes every transaction consecutively in a block which is ultimately called the "payload". Is this what you're referring to?


https://github.com/Blackcomb/nxt/blob/master/src/java/nxt/BlockchainProcessorImpl.java


The BaseTarget thing is described here;
https://github.com/Blackcomb/nxt/blob/master/src/java/nxt/BlockImpl.java

However, that doesn't require very many SHA256 operations. It just relies on the hashes of previous signatures to figure out what the appropriate time until the next block should be at a minimum. It seems like reorgs would be trivial to pull off if you are/were a major stakeholder, and you wouldn't need anywhere near 51% of the coins.

We are talking about POS, right? and specifically you are talking about NXTs implementation, right?
The security of all POS coins is based on the premise that getting 75% of stake is hard, and it's not based on any brute force calculation of SHA256 hashes. Please explain exactly how would a large hashrate benefit an attacker?
No special hashrate (more than the number of accounts per second), is required to create the main chain, and also not any special hashrate would be required to create an attacking chain. You only need the staking power.
Regardless of the baseTarget ajustments (which I seen in the Java code for NXT v1.3.3, not in any documentation because reading NXT docs is terrible, you never know what is actually implemented and what not), if you have more coins than those that were at stake then you can rewrite up to 720 blocks. No need for much hashrate. This applies to all POS implementations that I have seen.

The discussion I saw estimated that recalculating a better chain to attack Nxt would take the current bitcoin network hashrate several times the age of the Universe to do. I wouldn't like to comment but I haven't seen any advances on that which are backed by any calcs.

You would also need to calculate this attack chain in 720 blocks otherwise it would be rejected.

I say as much in the quote. Though, an FPGA should be an order of magnitude faster than a General-purpose computer (or even PoW hasher) for that type of problem.

I wouldn't be wrong to suppose no math will follow to back this statement, would I?

I tried that: https://nxtforum.org/proof-of-stake-algorithm/basetarget-adjustment-algorithm/ (linked from cite note 9 on the Wiki) requires me to log in.

A bank such a JP Morgan with a FPGA super computer can conceivably do it (without figuring out how many operations are actually required).


According to that, the updated algorithm was as suggestion. How are we supposed to analyze the specific PoS algorithm in NXT if you keep moving the goal-posts?

now think harder and see if you can find an answer that would be the the best possible solution for both problems.

wait!

what about a continual PoW

and a PoS

or just continual PoW

I know   Search nxtforum for "BaseTarget adjustment algorithm" thread (leads to Blind Shooter algorithm and how it interacts with the retargeting algo, in the same thread) if you are genuinely interested. I get the impression no one on BTT is, they just listen to the echo and then repeat it.

The above makes the Nothing at Stake 'problem' wishful thinking. At least in Nxt it does.

I have no idea what you're going on about.

why do you think there are many SHA256 operations involved?
That is what is required to calculate a longer chain that stands a chance of being accepted as legitimate.
The retargeting algo in Nxt plays an important role in this.

how would a large hashrate benefit an attacker?
See above.

it's not a matter of hashrate, it's 300 blocks * 60 seconds * 400 accounts = 7200000
Which POS implementation is this possible in? It doesn't look very secure.

what is "the stake"?
The stake is Alice's coins, 75% of all coins in existence.

were your 400 accounts forging on the main chain at block 5000 or not?
Assume worst case for coin, best in favour of the attacker.

There is no answer because the question makes no sense.
first answer this: why do you think there are many SHA256 operations involved? how would a large hashrate benefit an attacker?
it's not a matter of hashrate, it's 300 blocks * 60 seconds * 400 accounts = 7200000. Hashing that many SHA256 takes less than one second on a modern cpu.

The question is not clear because it talks about "the stake", but what is "the stake"? the total amount of coins? or the amount of coins actively forging at the given time? were your 400 accounts forging on the main chain at block 5000 or not?

If you control more coins at block 5000 than those that were forging at block 5000 then you can simply rewrite everything.

Bump.

I am genuinely interested in the answer,  I can only assume you are all busy with your calculators right now. I can wait.



My follow up question would then be...

Would doing this many SHA256 operations be at no cost?


If you still believe this would be free, check would it be possible to do. i.e. what is likelihood that you can do this many SHA256 operations to recalculate a better chain within the 720 block time limit?

Maximizing profit doesn't have to be equal to your "doing the right thing" or to reverse it "doing the wrong thin" might make you a winner.
You are oversimplifying, sorry.

No I still mine, just would prefer not to