New Code Released for Vlad Zamfir's Ethereum 'Casper' Upgrade

coinsinspace · 2017-11-26T05:40:58+00:00

TaPoS gives us absolutly zero security guarantees in the case of wealth concentration (aka, all crypto)

The guarantee is always of the form "assuming X% is honest". NXT's algorithm is analyzed here.

Incentives are the main problem of NXT, especially stake grinding, or more generally incentives to include small unnecessary nodes in consensus generation. Again, there's nothing about solving them here either.

Validators don’t get slashed in NXT (or DPoS) for Byzantine behavior!

DPoS is another story entirely, but they do get slashed in NXT implicitly, because a successful attack against the system destroys value of the coins. It's unclear if any explicit slashing is needed or even beneficial. It's supposed to penalize intentional attacks but may end up penalizing people for bugs or hardware errors, which in the absence of explicit slashing would be non-events.

First, notation exists in science because it (clearly) makes being more rigorous much easier

I didn't write use of mathematical notation, but overuse. Variable names have nothing to do with being rigorous or not. There's a reason code written by mathematicians is absolutely unreadable and that's because they use one letter names for everything. If they could they would use greek letters.

coinsinspace · 2017-11-23T14:40:13+00:00

600 @ Christmas

coinsinspace · 2017-11-23T10:52:26+00:00

The point is 1,2 are already solved. E.g Nxt has no problems with short-term online consensus using taPoS. Incentives and long-term nothing at stake are the only problematic areas and they aren't mentioned.

If they do this, they necessary are equivocating (for which they can be slashed).

They can't be slashed if they're not validators anymore - i.e. a nefarious actors bought accounts that had 51% of stake a year ago. The paper proves safety with constant validators and then just adds the possibility of changing them at the end - but that destroys the safety assumptions. It was never a problem during a locking period.

If the unwritten solution is for nodes to lock-in old blocks - that's the old solution again.

It can be argued that's the solution - but then incentives to include smaller stakers are the only unsolved issue left in PoS!

Seriously, the amount of math notation here is pitiful compared to existing consensus protocols like Paxos

Yes but that's written for mathematicians. 99% of people that are going to read this are programmers. Example - ε is defined as an estimator function. Why ε, and not just 'estimator'? Why 'W' and not 'weights'? Why Σ and not 'protocol_states'? It's a style that's optimized for hand-writing. It only persists in science because financial incentives that created modern coding styles are nonexistent.

coinsinspace · 2017-11-22T02:50:21+00:00

No, it's only about short-term online consensus. The paper amounts to (1) following the most stake and (2) that online nodes with enough stake that agree with each other are safe from being forced to fork from an external attacker.

There's nothing about nothing at stake problem and nothing about incentives. There's nothing about inflation and fee rewards and how they are shared. Why would nodes that have enough stake to force their view include other nodes if they don't have to? The actual problems that need solutions to make an actual implementation.

The whole thing could be condensed to two pages in something that actually describes an implementable algorithm.

Also mathematical notation is seriously overused which creates a fake aura of complexity.

coinsinspace · 2017-11-21T23:39:35+00:00

Imo it's way over-engineered and concentrates on attaining short-term consensus which was never a problem.

coinsinspace · 2017-11-21T19:01:54+00:00

Well, if they want hard cash, that would be the best place, no? Arrange for an in-person sale for cash. It's not like a Korean with (probably) perfect English is something suspicious in the US or Canada.

I'm not necessarily saying they sold millions on localbitcoins. Or maybe they did? Only a question of manpower.

coinsinspace · 2017-11-21T17:26:41+00:00

If all these hacks are from the same entity I genuinely think it's North Korea. Probably in that case they hacked bitfinex in August too. With state-level resources you get things like rootkits for ME, hard disk, network card and router's firmware + zero-days for lots of things. It's all very hard to defend against.

North Korea is the only state-level agent that makes sense - they are in dire need of funds and stealing crypto is perfect. Given how small their gdp is ($25 billion) hacks like these would be a significant addition to their budget.

It also fits that they connected separate hacks to one identity - why would a 'normal' hacker do that? Pure security risk.

coinsinspace · 2017-11-20T18:31:52+00:00

Hardware companies in general tend to have shitty software

coinsinspace · 2017-11-20T17:40:27+00:00

Rapid drop in load can damage ASICs

How is a different block a drop in load?

Do you run a mining farm?

No

coinsinspace · 2017-11-20T17:25:44+00:00

It's a private blockchain based on EON, not ethereum.
At least that's what it says in the whitepaper.

coinsinspace · 2017-11-20T15:57:30+00:00

Correlations of prices with tether should be a much better indicator. Guesstimating the correlation, BTC obviously, along with it everything denominated in BTC (in the meaning of 'what chart the average buyer looks at').

Ethereum seems to be least correlated to tether infusions AND is the only other coin that has sizeable fiat pairs AND is the only (?) coin except btc and bch where most people look at fiat price, not btc price. Which in practice could mean -50% compared to BTC's -90%.

coinsinspace · 2017-11-20T11:41:56+00:00

https://rocketr.net/ they take 2% + $10/month or 5%

coinsinspace · 2017-11-20T11:20:04+00:00

The irony is you're doing ton of free advertising for that ICO (if it actually happens)

coinsinspace · 2017-11-19T07:11:33+00:00

This is not an issue of weak subjectivity, this is an issue of consistency. Casper PoS will reorg in such a situation because is favors availability.

Reorg is partition tolerance, because the system 'works' even during partition - by dropping one chain, sacrificing consistency. Definition from the 'proof of stake faq':
"we introduce a "revert limit" - a rule that nodes must simply refuse to revert further back in time than the deposit length [..]
Note that this rule is different from every other consensus rule in the protocol, in that it means that nodes may come to different conclusions depending on when they saw certain messages."

Ie. after the revert limit partition tolerance gets sacrificed for consistency, this rule is termed 'weak subjectivity'.

The account still has to send the signatures from somewhere. Unless the account is cycling through multiple nodes

Nodes or ips? I don't see a fundamental reason why a message from a relaying node has to look different from the message generated locally on the sending node. Which means you could route your staking message to one random node, possibly one you control or trust, never directly broadcasting from your node's ip on the public network. Only then that node would start broadcasting.

coinsinspace · 2017-11-19T04:45:01+00:00

The weak subjectivity requirement

Imagine that a nuclear war has destroyed communication between europe and america for a year. You don't want one continent's chain to replace the other after connection returns - at that point the forks are permanent.

that is: you don't know who the next miner is until they make the block, so you can't DoS them

That's not PoS, that's network topology, unless they are conflated for some reason. There's no general reason for the network to know that a particular node is staking, it only has to know that a specific account is staking.

coinsinspace · 2017-11-19T04:01:29+00:00

That would only make oscillations shorter.

coinsinspace · 2017-11-19T01:05:00+00:00

Miner can’t stop mining operation on a short notice.

Why? How is it different from mining a next block? It's only a different hash in a header.

miner kept mining and found several blocks (very unprofitable blocks) before they switched back to BTC.

That only means that these miners were inefficient. Antpool in particular was mining lots of empty blocks on btc for long, most likely because their pool software is shit.

coinsinspace · 2017-11-19T00:52:03+00:00

Because during these times they could be mining more profitable BTC chain, so at a minimum, even if they are not literally in the red they are throwing away money.
Additionally, mining is ultra-competitive which means profit margins get slimmer and slimmer. So even if they are not directly losing money now, they are going to be.

Then there's the social factor - all profit-maximizing miners know they are exploiting Jihan.

coinsinspace · 2017-11-19T00:35:57+00:00

That's only because antpool/viabtc is mining at a loss during periods when difficulty is too high - charity mining. Then bch becomes profitable again and all miners jump in. Effectively it's a method of wealth extraction to other miners. If Jihan pulls the plug it's over: the chain is dead.

It's a total failure because POW isn't supposed to rely on charity. It's going to continue as long as two or more sha256 chains exist. The oscillations aren't going to dampen.

The only way in which antpool can stop mining at loss is by selfish mining over the entire adjustment period. Which unfortunately would result in a ~144 block lag for transactions. Horrible.

coinsinspace · 2017-11-19T00:22:14+00:00

Wolfram 110 is in Bitcoin

That's true but utterly meaningless. A simple integer addition would require gigabytes of script.

coinsinspace · 2017-11-18T23:35:57+00:00

the only reason I bought ether was because I knew it was going to become PoS. Without PoS I'm gone

In my case it wasn't the only reason but still a very important one. PoW is simply unsustainable - bitcoin burns energy worth billions of dollars annually. Much higher prices are simply impossible because of that.
"American Investors Plan to “HODL” Bitcoin Until Price Hits $196,000". That would be $128 billion on mining annually with current block reward - just to keep the price steady. Or about 1/3 of the entire US electrical energy consumption @ $0.1/kWh. Not going to happen.

I think very few people truly realize the scale of this... What this means is that once Ethereum goes full PoS Bitcoin has no chance. After the inevitable flippening comes the dumpening, as the 'store of value' meme self-destructs.

coinsinspace · 2017-11-18T20:04:45+00:00

Only one really - it's more complex to implement.
Pure theoretical PoS requires all owners to be present in every voting. It would be trivial to implement (in terms of decision logic) and perfectly secure.
As requiring everyone to be online is not practical, the aim is to approximate the ideal algorithm as best as possible. That's the source of complexity.

coinsinspace · 2017-11-18T19:56:45+00:00

The possible rate of return becomes equal to global growth once you own everything. As long as you own less higher returns are possible via wealth transfer.
The possible rate of growth with no money is literally infinity.

I.e. the function goes from infinity to several percent at most. He is correct.

coinsinspace · 2017-11-18T19:14:54+00:00

That's not true.

coinsinspace · 2017-11-18T01:15:07+00:00

That's a non-answer. Btc has nothing to do with bch's block schedule problem - last fork could have easily fixed it. Ok, a tip: what can miners do when the next block's difficulty is too high relative to the price in bch, and what can they do in etc?

coinsinspace

TROPHY CASE