Topic: PPCoin is NOT a decentralized cryptocurrency - page 4. (Read 10995 times)

Do you really think, you're on the same understanding level as killerstorm as you seem to be trying to implying the same understanding as him. Even though he disagrees he actually seems to be relatively intelligent.

Agreed.

How can you not have a math analysis of something you created. Oh wait...maybe because it wasn't you right?

No need to properly inform people of how your new system works, just get it out there and all the kiddies will buy it because it is a "crypto-thingie".

Nevermind that you didn't analyse your protocol, I haven't even seen evidence that you know how the protocol works. Remind us again why you refuse to post the protocol specifications? Maybe someone else wrote parts of the code and disappeared, leaving you clueless? IMHO killerstorm is being far too respectful towards you than he should be.

You are right I don't have a math analysis of how much coins are needed to attempt control of block chain. First it's more difficult than Satoshi's design, secondly I think there maybe other practical attacking vectors that I have missed so putting a math formula there as the final say on security is a bit misleading as well. So no I don't think I am ready to do this type of analysis. I think I have mentioned this before.

I did not claim that you need 50% coins to control ppcoin block chain. Much less of that would be enough.

It may not match your expectations but I did what I can to contribute, rather than sitting there and accusing other people being lazy and greedy while they are the ones doing the real work. How convenient.

If you are so helpful then why don't you polish your analysis and continue discussion on the security properties? Instead you would just launch your personal crusade to attack me and ppcoin project. If you worried so much about investors then why I haven't seen one pm from you describing the vulnerability of ppcoin and discuss with me ways of fixing it? I have received quite a number of pms but none are from the detractors as their main goal is to discredit ppcoin in public.

However given all that I have endured from you, you are still welcome to pm me if you truly wish to discuss about security analysis of ppcoin. Otherwise we would just have to part our ways.

I don't think it's really that hard. For example, Satoshi's analysis of proof-of-work security is something undergrad math student should be able to do.

PPCoin is quite a bit harder to analyze (which is a bad thing), but numeric simulation isn't hard, again something undergrad student should be able to do.

Sunny King definitely knows both math and programming. If he haven't done simulation this is just because he doesn't give a fuck about research, as long as people trust that his coins are valuable and buy them.

Also, in many companies, particularly ones which work with important, mission critical things, programmers are required to write specification and tests before they start coding.

I don't think so. You replied with an asymptotic approximation of my formula which shows that splitting stake into many pieces doesn't help. (Which is understandable.)
I guess this confirms that you accept my formula, or at least you don't have a better formula. Otherwise you would have shown your own numbers to dismiss mine.

So, well, maybe indeed my formula isn't correct. It was a very quick and crude analysis anyway. So where is YOUR formula?

You've designed this proof-of-stake system, so you must have some estimate for cost of double-spend attack, right? Right?

IIRC you said that one needs at least 50% of stake to own the network. Can you show at least some sketch for a proof for this?

Or -- gasp -- you don't really have any mathematical estimate, just your intuition? This really shows how security is your priority.

Note that Satoshi have published security analysis in his paper. See section 11 in the Bitcoin paper. Satoshi wrote two pages of text to explain fairly basic probabilistic model, then he included a C program which does the calculation and gave concrete numbers of several scenarios (i.e. 5 confirmations is enough to get less than 0.001 probability of double spend from attacker who has 10% of network's hashing power).

Do you think that Satoshi was in ivory tower when he wrote that?

(Now, guys, this was a real ownage.)


I never said it is. If you have something better show me that I was wrong.


Is it a smear campaign if I just state facts?


Yeah that will surely shield you from criticism

I'm not writing it for you, idiot, I'm writing it for people who consider 'investing' into ppcoin. They have a right to know.

I do not ask people to trust me, I ask people to question you before they get involved. That's all.

Again, nothing personal.

Actually there is a method to provide accuracy, it's called a mathematical proof.

Of course that requires alot of work research and skills, and somebody capable enough to do it wouldn't even fork the bitcoin code but start over.

Sigh, killerstorm, I already replied to your formula the same day I don't think they are correct. Whatever you believe, you can feel all superior and think your 'security analysis' is all foolproof, and warrant personal attacks and smear campaigns of ppcoin.

Sorry I don't think a real researcher on these issues act like you do. They are probably more level headed and responsible. So I guess we'd have to part our ways then.

Right now my priority is operational and security issues. Design paper may be updated in the future but there is no guarantee at this moment. Unfortunately that's how things are done outside ivory tower. I feel with the design paper + source code out there if you truly want to do some analysis of the algorithm you already have all you need, not out of the norm even for pure research oriented work you'd have to make some effort to understand things.

You can also help to make the learning curve a bit less steep, by creating some wiki articles/discussion topics for example.

Civil or not, my formula is the ONLY estimate of cost of double-spend attack for PPCoin (as far as I know). Ironically, I demonstrated that attacking PPCoin's PoS is somewhat hard and thus it might be secure.

Without this estimate it's just faith-based currency. Like, Sunny King's intuition says that this code is secure, then it must be it! All praise Sunny King!


People try to find holes in crypto constructs all the time. For example, best known preimage attack on SHA-256 is: "41-round SHA-256 out of 64 rounds with time complexity of 2^253.5 and space complexity of 216". It is completely theoretical since it doesn't even attack full SHA-256 and 2^253 time complexity is absolutely impractical.

But these kind of theoretic attacks are very important since they show that even very clever people cannot find ways to attack SHA-256. We were able to get some confidence in this crypto function only after years of analysis.

But Sunny King wants people to simply trust him...


Litecoin proposal is PoS+PoW, you have pure PoS. It is a completely different thing.

Also, bribery isn't the only way to attack PPCoin, one having access to considerable amounts of "stake" can try to do that. Practical double-spend attacks require much less than 50% of coins.

---

If Sunny King has no trust in theories, perhaps we can show it in practice? We can organize a fund which would purchase as much ppcoin as possible. Then it will try to perform double-spend attacks... Alternatively, fund can bribe people to use their stake.


1. I don't have my own proof-of-stake design.
2. I think that PPCoin is interesting and Sunny King is likely a smart guy.
3. However Sunny King has too much ego which likely hurts his currency.


Yeah I guess those people who try to attack SHA-256 all have too much ego, they simply should have trusted SHA-256 designers.


Sure, you can just dismiss formula which estimates costs of attack simply because a guy who wrote that formula doesn't sing you praises. That's how it works among mature people.


Yeah I know, you developed it for 9 months, then two weeks after release you found a way to make it much better and completely different. Your sudden enlightenment has nothing to do criticism you read on forums.


Apparently spending several hours on analysis and writing down a couple of formulas doesn't count as meaningful now.

As for unreasonable attacks, you should probably send a message to that guy who found 2^253 attack on a weakened SHA-256: his attack is just unreasonable, he shouldn't have published that paper. Likely he's just too mean and has too much ego and doesn't want to engage in meaningful discussions.


Oh, how cute, so when will you publish detailed design documents and analysis so we can discuss it?

IIRC you said that you have it, but you don't want to share it with anyone.

yup, thats right...why not take it in PPC or Scamcoin?

Is this in reference to the 250BTC that RealSolid begged to be paid? lol...

beat me too it smoothie...did he not take it in bitcoin too? 

I agree. Claiming you (Sunny Drag Queen) spent $100,000 to $200,000 of development time on PPC is EGO


AND A LIE.

The point about egos is on point. Most criticism (not all) is driven by personal feelings. This type of criticism is just noise and should be ignored.

That said, killerstorm raised a very important point. The workings of PPC are opaque. Learning the  protocol requires sifting through the code. It is not reasonable to expect outsiders to do this.

This makes it very difficult for outsiders to analyze PPC. A new white paper which contains details sufficient to implement ppc independently would solve this problem.

Sunny has to be the person to write this. Sonny, lay out the protocol details and let these details speak for themselves.

just my 2 ppc here

Sunny contacted myself directly after seeing my issue with payments below 1 ppc.
For my limited experience and first impression he seems very willing to discuss any issue with ppc.

+1 well said, too much ego in this place

I am perfectly willing to engage in discussions however to my disappointment only cunicula among the self-proclaimed proof-of-stake experts seems to be capable of civil discussions. I don't see much merit in your so-called security analysis. I understand your criticism, but coblee also thinks the type of attacks you are concerned with are not practical when you presented the same argument to his litecoin proposal. Sure I will consider improvements in the future as problems arise, but that's hardly a valid excuse to paint ppcoin design as worthless.

The problem I see with your camp is that you guys have too much ego and think only your proof-of-stake design is good. The so-called critics (except for cunicula) did not give even a tiny credit to ppcoin team and me. I only hear regurgitation of how your design is more legitimate and superior blah blah plus a lot of dirty words thrown on ppcoin.

I am sorry I cannot acknowledge this type of 'criticism' as constructive. No you didn't contribute to ppcoin, with or without your 'harsh criticism' I was going to introduce the v0.2 improvement to ppcoin, which I entirely came up with by myself.

I hope you can realize the error in your ways and start engaging in meaningful discussions without unreasonable attack on ppcoin and me. I think you are smart and maybe can contribute some good ideas if your mind is in the right place. As I said before I wish everyone of us can look deeper and realize that maybe we work towards the same larger goal so we can throw away our petty differences and be respectful to each other. I do not hate all these litecoin trolls either who throw insults on me freely, but I pity them and hope one day they would realize what they did was wrong as well.