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Showing 20 of 29 results by Ryo
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Re: Young women for bitcoins
by
Ryo
on 06/02/2011, 18:59:45 UTC
Guys, it's not even the same profile, there are two Rosalinas. Check, for example, the post count. Either the first account was banned or someone is trying to double-scam.
Post
Topic
Board Pools
Re: Cooperative mining (>10000Mhash/s, join us!)
by
Ryo
on 04/02/2011, 18:29:30 UTC
I don't understand pool cheating all that well, but to make an educated guess, the only really secretive information is the total number of shares in the current round.

That's correct (regarding the specific type of cheating I described; there may be other ways to cheat).
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Topic
Board Pools
Re: Optimal pool abuse strategy. Proofs and countermeasures
by
Ryo
on 04/02/2011, 18:20:45 UTC
If you critize my trustworthy

I have no opinion about you, good or bad. My interest is what can be done, not what is actually done.

Quote
then yes, I can cheat users all the time, I don't need to hide stats to do so.

As the pool was before, with full statistics, users could check whether their revenue was really ((50/total_shares) * nb_shares). They could also, by talking with each other, evaluate if the pool reported a plausible number of total shares. While there were ways for the pool to cheat, the statistics allowed users to check it didn't cheat too much.

My understanding of the way your pools works now is: miners find shares, they receive bitcoins, but they can't know how much the pools pays each share. As long as you release data on how much a share is worth, "cheating" becomes possible. I was wondering if you had found a way to preserve both openness and fairness.

I believe having the value of contributed shares decrease over time would also fix the cheating problem, ensuring that the expected gain of joining is the same at all times. And you'd still be able to display the statistics like before.
Post
Topic
Board Pools
Re: Optimal pool abuse strategy. Proofs and countermeasures
by
Ryo
on 04/02/2011, 18:01:27 UTC
Not exactly. For now I disabled some numbers completely (expected round reward or worker shares), but I plan to reimplement this from round-oriented to time-oriented stats soon. So you will still see how many shares will miners does and so.

I'm not sure you can remove the stats that allows one to "cheat" and still provide users with proofs that the pool is fair. Did you find a way ?
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Topic
Board Marketplace
Re: Young women for bitcoins
by
Ryo
on 04/02/2011, 17:23:15 UTC
o.O look at her right hand, she's not holding anything at all, the writing may very well be real handwriting but the whole sign is photoshopped in. For christ's sake her finger tips blend into the sign!

the two halfs of the sign are different colors, the boarders look like different widths depending on were they appear on the sign... seen better shop jobs on 4chan...

Using my fabulous Google magic, I believe I can safely say that:
- you're talking nonsense
- but the picture is fake

Here's our girl:
http://www.escapeartist.com/Offshore_Webhosting/Girl_IBC3.gif
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Topic
Board Pools
Re: Optimal pool abuse strategy. Proofs and countermeasures
by
Ryo
on 04/02/2011, 17:18:08 UTC
If someone cheat and get more money on on quick blocks, than someone must lose on quick blocks. I am surely will not be the looser (nor will my customers).

You don't lose on quick blocks. You lose on slow blocks. People who "cheat" simply lose less than you on slow blocks.

If you want to check whether people are "cheating", don't look at quick blocks. Chart computing power against time, and if people cheat, you'll notice a drop as blocks grow longer.
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Topic
Board Pools
Re: Optimal pool abuse strategy. Proofs and countermeasures
by
Ryo
on 04/02/2011, 14:04:26 UTC
In this thread, the author finds no evidence of massive use of this strategy
http://bitcointalk.org/index.php?topic=2941.0
(I didn't read the paper since I find it strange to ask for a payment for something that may or may not contain anything interesting; and I didn't find any hard numbers in the discussion)

Well, in the discussion, you could have seen confirmation that people who bought the paper didn't feel cheated. The reson I'm asking money first is that I don't believe people would donate, especially people who want to abuse pools. However, it's been some time since anyone downloaded the paper, so here it is, for free:
http://www.bitcoinservice.co.uk/files/111

If anyone wants to donate (and that would incite me to write more about bitcoin), here's an address:
1ESWeHDPSEErzr6tcm3aToVGXKUe8kA9D8
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Topic
Board Bitcoin Discussion
Re: What does Quantum Computing mean for Bitcoin?
by
Ryo
on 30/01/2011, 20:09:37 UTC
Somebody needs to write an article series on cryptography.

I'm currently working on a series of articles explaining the concepts used in Bitcoin, like proof-of-work and hashes. I would have to study a little bit before fully understanding exactly what quantum computers can do.
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Topic
Board Bitcoin Discussion
Re: What does Quantum Computing mean for Bitcoin?
by
Ryo
on 30/01/2011, 09:22:38 UTC
The "something else" has to be something that quantum computers are not better at solving than classical computers. Quantum computers do not magically make P=NP, so there are still be problems where solutions are hard to find but easy to check, even with cheap quantum computing everywhere.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 19:42:59 UTC
If so than to me this seems to be an exercise in futility. Past performance does not guarantee the future results.

This is not about past performance, on the contrary. At any point in time, no matter how long the round has been active, there is the same expected time before finding a block. But what you will gain is not constant, it depends on the number of shares. Because of this, you can optimize.

Quote from: slush
because each instance of pool has own merkle root. So submitting shares from another pool (even based on the same code) won't work.

Thanks, I will correct this.

Quote from: slush
Good point is the switching between pools. But unless there are not two pools with similar hashpower, it's probably not relevant.

Even with two identical pool, unless they start their rounds at the same time, you can switch between them and gain a lot.

Quote from: slush
I'm just missing some graph in section 4.2, which shows time (X), hashpower(Y) and vertical lines where new block was found. All of this is public information and it would add more weight to sentence "there was no evidence that people gave up on old blocks".

I have to admit I have been lazy. I intended to provide that graph, but there was a network outage during the time I gathered my data, so there was a gap of a few hours, and I didn't want to start again. If you keep a log of computing power over time, and rounds over time, maybe you could send me the data, so I don't waste your bandwidth again ?
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Topic
Board Development & Technical Discussion
Re: Bitcoin Addresses
by
Ryo
on 24/01/2011, 13:30:17 UTC
* It possible to generate the same address twice

* It is extremely unlikely, you're more likely to be hit by a falling asteroid next time you leave your house, several times in a row

* It would take millenia to generate all addresses if you generate only a thousand per second

* Coins are attached to addresses, not to online people. Two people who have the same address share the bitcoins attached to them, and won't notice until the other one spends some.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 10:18:39 UTC
I do mean expected value, but by saying "gain" I make sure we're not talking about expected time before a share or some other value.

Again, I didn't make calculations, I'm just using intuition (which can be tricky), but I'm pretty sure that expected gain decreases if you mine all by yourself and you're not powerful enough to have a good chance of finding a block before the next increase in block difficulty. At current difficulty, my CPU would take about half a year to have a 50% of finding a block, but before that difficulty will have increased, so my chance of finding a block in half a year is actually lower.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 09:32:59 UTC
Maybe you would be interested in publishing economic articles at The Bitcoin Times, a new fledging magazine.

I am no economist, even if might have things to say about game theory and optimization from times to times. I can write about computer science, though, and I already asked in the "bitcoin times" thread if you would be interested in publishing a series of articles about the science behind bitcoin or other crypto-stuff. Writing such articles is time-consuming, and I wouldn't want to do that unless some interest was voiced beforehands.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 09:25:32 UTC
I agree, this was written from the point of view of a miner estimating his expected gain from one specific block (or more precisely, one round), but as long as blocks (or pools) are exchangable, there is no reason to do this. If he has a choice, a small miner should switch to a pool with a "younger" round. I don't belive he should start mining all by himself is there is no other pool, though; his expected gain would drop close to zero, because of the increasing difficulty.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 07:42:09 UTC
Let's take two simple scenarios:

- A pool with three people. Two of them have clusters of 5970s, one of them has an old Pentium IV. For blocks that are found before 10000 shares or so, that third person won't even have submitted one share, and thus will get nothing, not even a small fraction of a bitcoin.

- A pool with three people. Each of them has an old Pentium IV. Blocks will take a long time to be found, but most likely a lot of the members will have submitted at least one share.
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 07:24:18 UTC
In connected mode, the block reward is spit among currently-connected nodes only, according to the hash/s that they were contributing at the time.

It seems easier for the server to cheat in connected mode. With contributed mode, if they have doubts, miners can log how many shares they contribute, check how much they gain, and decide whether it's fair. The server could "invent" imaginary shares to keep some bitcoins, but at least you have some hard numbers to check. With connected mode, how would you know if you got a fair share ? What if the server pretends you were not connected when the block was found ?
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Topic
Board Bitcoin Discussion
Re: Abusing Bitcoin mining pools: strategies for egoistical but honest miners
by
Ryo
on 24/01/2011, 07:18:53 UTC
I don't understand this. In the extreme, if everyone left a pool, why would a miner join it? They would get a block no faster than working on their own and they would pay to previous workers who had shares.

In the extreme, yes. But if the powerful miners leave after a few thousand shares, the less powerful miners may find it profitable to stay, because they will get a bigger share of the rest. The problem, for small miners, is that when you're up against people that have 1000x your computing power, they will find blocks before you even contributed a share, and you will gain nothing.
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Topic
Board Pools
Re: Cooperative mining (>10000Mhash/s, join us!)
by
Ryo
on 23/01/2011, 21:11:52 UTC
Unless I'm mistaken, this is the expected gain for mining all by yourself. I compute my expected gain by finding how much of the total computing power of the pool I have, and how fast the pool generates blocks. I didn't try to prove it, but it seems logical that this number would be somewhat lower.
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Topic
Board Pools
Re: Cooperative mining (>10000Mhash/s, join us!)
by
Ryo
on 23/01/2011, 19:19:20 UTC
May I ask how you compute your expected gain ?
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Topic
Board Pools
Re: Cooperative mining (>10000Mhash/s, join us!)
by
Ryo
on 23/01/2011, 18:34:53 UTC
This thread may be of interest to pool miners:
http://bitcointalk.org/index.php?topic=2941.0