Topic: delete - page 6. (Read 34074 times)

Still at block  4544 .. more popcorn needed:)

Re the first question, if you disallow all earlier timestamps - what happens when I start mining and publishing blocks with timestamps 2 hours ahead? I now have another 2 hours in which to mine the next one - during this time, no honest nodes can mine (_no_ earlier timestamps than my block are considered valid), and as soon as the timestamp for my most recent DoS block rolls by, I have another one ready and mined (I have 2 hours to prepare it) to publish, so I can keep denying the rest of the network service while I mine the chain with the most work in it, even though I don't have much hashrate.

For example, if your chain has 1 minute blocks, but I have 2 hours in which to mine my next DoS block, I need less than 1% of the hashrate to do it.

What about if we take the median of the past 3 blocks as the lowest acceptable timestamp?

Now:

1. Attacker mines a block (with a timestamp 2 hour in future). Consider this a random occurence, and evaluate probabilities _after_ this happens, because the attacker is going to keep getting blocks randomly, and each time he gets one, he gets an opportunity.

Currently, honest nodes can mine - 2 of the last 3 blocks have "normal" timestamps, so the median is low enough that everyone can mine. Our attacker needs to accomplish (2).

2. Attacker mines a second block with a timestamp 2 hours in the future. His chance to do this before the rest of the network (once (1) has already occured) is exactly his proportion of nethash.

For example, an attacker with 10% of nethash, on a chain with 1 minute blocks, achieves (1) every 10 minutes, and once in every 10 times he does (1) he manages to do (2).  Ie. he can DoS the network every 100 minutes on average.

But once he's managed to achieve (2), he can keep doing it, even with very little hashrate, because the mainnet can't mine anything, or rather all their efforts are wasted - all their blocks with honest timestamps are invalid, so the attacker can keep mining blocks with timestamps that will be valid when he releases them, while everyone else keeps trying to mine blocks with timestamps that won't be valid. Immediately the most recent DoS block timestamp rolls around, our mainnet should, on average, take another minute to get a block with a valid timestamp and break the cycle, yet our attacker is ready to release his pre-prepared block right away, before they get a chance to do so.

In fact, it gets worse, because once he has 3 in a row, the honest nodes now need to mine 2 valid timestamped blocks in a row in order to unfreeze the network. Good luck doing that with our attacker continually releasing his pre-prepared blocks. You'd either have to fix the problem and roll the whole chain back, or get the honest miners also trying to generate timestamps immediately after the most recent DoS block (eg. the honest nodes intentionally generating future timestamps) which would turn it back to a 51% attack.

Note that our attacker can not only deny mining to the honest nodes, he can also achieve the chain with the highest total work, without needing a majority of the hashrate to do it, because he can keep working whilst stopping everyone else from doing so.

So, the median of 3 blocks alone isn't the fix, since on chains with short blocktimes the 2 hour window in the future where blocks are accepted as valid is also an issue.

I actually suspect the 11 block median isn't random or any kind of arbitrary choice, and that Satoshi made it that way for a reason. If our attacker has to get 6 future timestamped blocks in a series of 11, rather than just 2 out of 3, his job of beginning the attack is much harder.

About your second question, I haven't considered why that is. Maybe it's related - it's interesting, and I'll ponder it.

I'm quite sure this has been discussed before, but why clients does not make automatic checkpoints? I understand that transactions which are at least 6 blocks old, are considered valid. There should be no reason to re-arrange the blockchain after that, for any reason.

So I'd like to hear what is the reasoning behind the fact that there are no automatic checkpoints? Maybe manually overrideable?

Interesting. Can you tell more?
Another question; Currently it does not allow block timestamp <= median time.. ie eventually the timestamp has to increase. Is there any reason for that, so could it be < mediantime, which would allow same timestamps?

A bit of pen-and-paper (plus spreadsheet) work indicates that BCX will indeed do this - it's an interesting vulnerability, so thanks BCX for exposing it. I agree with Nite69 about the 3 block median - I'd already considered that after he posted yesterday about disallowing _all_ earlier timestamps (ie. taking median timestamp of 1 block), since it opens up another rather nasty vulnerability if you fix it that way.

Hmmm tissues, and toothpaste odd combination. Is that your substitute for hand lotion?

You do realize I"m out of popcorn.  WTH am I supposed to do now???

This actually sounds fair!!!!

yes.  that's the whole point of a multinational company with worldwide influence:  capital flight.  Russia, Australia, Botswana, DRC, Canada, Angola, ghana, and Brazil are alternate places to do business if South Africa doesn't.  and Zimbabwe produces fewer diamonds than any of those countries:  why would DeBeers give a shit?

so basically, you're arguing against my point by redefining the word 'government'.

interesting, but we disagree.

Please see also this:
https://bitcointalksearch.org/topic/m.5567450

bitch, its about goddamn time for you to put up some fireworks.

hit me up once you're about to light up your shit.

i want to be in the front line, watching

If it's the same discussion as in this thread then there's no point. There are cities that offer free legal services to their residents, and I suggest anyone who will suffer any damages due to OP's actions will use them. And if their opinion is that nothing illegal has happened then that's it then. But I suspect they might have differing views as well.



There are likely AUR holders who will suffer damages and live in a country where whatever OP is planning on doing will be illegal. Doesn't matter where OP lives. The amount of damages then dictate whether it makes sense to pursue it further.

Are you telling me De Beers controlls the diamond market and rose to the top without any aid from the South African / Zimbabwe government? They just set up shop, and every other business minded person turned a blind eye on to the opportunity of making money from diamonds... for no apparent reason... ran it like that for like the last 100+ years, and thus got in control of the market? And by government, I mean any entity that has a monopoly on power and is "authorized" to use force without any repurcussion for their actions. That can include other rebels who are anti govt and want to overthrow the current govt and put someone favourable to them.

As for teh Pump n dump, you are talking like that is an external event "happening to people". If someone is selling, it means that someone is buying at that price.... voluntarily. That's teh key word there... voluntarily. So what if a group of people take a stand and say they will not purchase at a price higher than so much and together decide they will all sell it at this price or higher? You are taking accountability away from them when you say they are "left holding the bag". If a person chooses to invest in something where he knows a lot of teh other buyers are prone to panic and can fluctuate the prices based on their collective panic, he is choosing to take that risk by not considering that dynamic while parting with his money.

We can allow new blocks to travel 1 block back in time, so I'd modify my earlier fix:

This should be in effect after the block 5400. Wheather or not that is the flaw BCX is planning to use, this should be fixed anyway.

lo, didn't think about it earlier; but now it is not only one byte fix, it is one bit fix  :-D

DeBeers is the diamond cartel controlling 50% of the world's inventory, and does this without the power of the government to function.

Sinaloa Cartel is a group of criminal drug organisations that operates worldwide, and functions in direct opposition to the government.

three incumbent Canadian wireless companies collude together in a cartel to maintain some of the highest prices in the world for phone plans, and actively attack new market entrants.  this is done despite the efforts of the government regulator.

cartels don't always require the power of government.  it does help when the government is involved, but not essential.


a pump and dump is more fair to the people within the circle i.e. cartel.

pump and dump relies on market manipulation and the cartel maintaining its strategy (i.e. "hodl") until the pre-determined signal.  this is contrary to free market where everyone would be acting as independent agents.  the precise timing to provide optimal payout relies on maintaining information asymmetry over the competition unfairly through collusion.  if you're in the cartel, you make money, and if you're out, you get to be bagholder.  that's not an even playing field.  

I would have to call BS on that.... a cartel always requires the power of the govt to function. To act upon their agenda, they will require favourable laws (aka blocking fair competition), the muscle of the state (cops, legislative threats, etc) and many other "favours" from a central agency. It is simply uneconomical for a cartel to block competition with their own money. Now in the freemarket world of Crypto, a cartel cannot exist. There may be whales and sardines, but in all fairness, they are whales because they invested their time and resources (brains, skills) to get there. Pump and dump is a completely fair process. What would be unfair is a central authority who is brought in to control this method (aka threaten the whales with violence for non compliance) so that the horde can enjoy artificial stability.

so basically the US gov and its bankers  

Depending on where you live, US federal code may or may not apply to your activity.  

By cartel i mean a group of people that follow an agreement to follow the same market strategy in the manipulation of an asset.  members of a cartel engage in price fixing, manipulating output, manipulating market share, rigging bids, and division of profits.  the aim of a cartel, whether in industry, stock market, or cryptocurrency, is to increase the members' profits by reducing competition.  if you research the current pump-and-dump groups and the recent pump and dump of auroracoin, you can observe a cartel in operation.  

I doubt you even know what you're talking about. And so what? What is "Illegal"? Some Govt declared mechanism to decide whom to aggress upon? This is open source man...It has freedom to evolve and will always turn out better than before. The outdated will perish, and yes, it will have victims... it is up to you to adapt.

By cartel, I assume you mean an organization of people subject to the RICO criminal statute (18 U.S.C.A. § 1963) ?