backdoor-merged-mining with cheating miners

[Schwede65]

The three pools known with “merged mining”:

1. masterpool.eu  did 20 NMC-Blocks since merged mining
2. nmcbit.com did 6 NMC-Blocks since merged mining
3. simplecoin.us did 10 NMC-Blocks since merged mining

36 blocks have been “officially-merged-mining” found, hashrate complete: ~100 Gh/s

130 have been found

94 by the “rest” of NMC-Miners, it must have a hash-rate ~350 Gh/s to do so

backdoor-merged-mining is a thinkable reason, with cheating miners, because there is no post I have seen

[1715434466]

1715434466

[322i0n]

I think this will be bad for namecoin protocol as well as the miners being cheated.

[memvola]

backdoor-merged-mining is a thinkable reason, with cheating miners

What does that mean, in technical terms?

EDIT: Do you mean some pools are doing merged mining but not passing back the coins to the miners?

[Schwede65]

backdoor-merged-mining is a thinkable reason, with cheating miners

What does that mean, in technical terms?

EDIT: Do you mean some pools are doing merged mining but not passing back the coins to the miners?

what do you think, when there is a necessary power of 350 Gh/s with no infos where it might comes from?

I think one/some pools do merged mining without informing their miners. Backdoor in their own wallet.

[iddo]

Is it impossible to detect? Because the way it works is that the pool pushes to the miners basically a hash of the block transactions that need to be signed, and the miners try to generate a valid hash on the hashed data that they received? But maybe you can detect that the nonce range is fishy, because the nonce has to contain the hash of the namecoin block? If it's impossible to detect then the only way for a miner to avoid being cheated is to use one of the merged-mining pools?

[Schwede65]

Is it impossible to detect? Because the way it works is that the pool pushes to the miners basically a hash of the block transactions that need to be signed, and the miners try to generate a valid hash on the hashed data that they received? But maybe you can detect that the nonce range is fishy, because the nonce has to contain the hash of the namecoin block? If it's impossible to detect then the only way for a miner to avoid being cheated is to use one of the merged-mining pools?

i dont know, how to detect them, but maybe there are some coders who can do this.

the pool(s) who do so, must live with that big abuse of confidence - yet and in the future

[bulanula]

This is VERY LIKELY to be happening. Bring down the scammers !

[iddo]

i dont know, how to detect them, but maybe there are some coders who can do this.

the pool(s) who do so, must live with that big abuse of confidence - yet and in the future

OK, I asked in #bitcoin-dev on irc:
http://bitcoinstats.com/irc/bitcoin-dev/logs/2011/10/10/3
Backdoor merged-mining can be detected after the block was generated, but not while generating it.
See e.g. http://digbtc.com/ regarding which pools found which blocks.

[Schwede65]

i dont know, how to detect them, but maybe there are some coders who can do this.

the pool(s) who do so, must live with that big abuse of confidence - yet and in the future

OK, I asked in #bitcoin-dev on irc:
http://bitcoinstats.com/irc/bitcoin-dev/logs/2011/10/10/3
Backdoor merged-mining can be detected after the block was generated, but not while generating it.
See e.g. http://digbtc.com/ regarding which pools found which blocks.

Where can i see, who found NMC-blocks?

Another question is: Could it be seen in the BTC-block if there was some (backdoor) merged-mining?

[teukon]

This is most likely due to the operator of a large pool using all the hashing power for merged mining but only paying out the Bitcoins.  Any miners with a standard Bitcoin pool are expecting a certain payout in Bitcoin for their hashing power.  Starting merged mining at the pool does absolutely nothing to change this (aside from possible a little server downtime) and so is a good opportunity for profit.  If miners actually want the namecoins then there is a selection of pools which payout namecoins too.

Does anyone have any evidence to support the idea of there being a way of actually cheating with merged mining?

[Graet]

This is most likely due to the operator of a large pool using all the hashing power for merged mining but only paying out the Bitcoins.  Any miners with a standard Bitcoin pool are expecting a certain payout in Bitcoin for their hashing power.  Starting merged mining at the pool does absolutely nothing to change this (aside from possible a little server downtime) and so is a good opportunity for profit.  If miners actually want the namecoins then there is a selection of pools which payout namecoins too.

Quite possibly.

We have not implemented merged mining yet, busy getting our new server up and setting up a US server, then a couple more things in our priority list.
If/when we decide to MM we will email our members and announce in this forum - as we do with all major changes.

We do recognise the tough times miners are coping with currently so are paying 55BTC per block as a way to offer extra value to miners

[Schwede65]

This is most likely due to the operator of a large pool using all the hashing power for merged mining but only paying out the Bitcoins.  Any miners with a standard Bitcoin pool are expecting a certain payout in Bitcoin for their hashing power.  Starting merged mining at the pool does absolutely nothing to change this (aside from possible a little server downtime) and so is a good opportunity for profit.  If miners actually want the namecoins then there is a selection of pools which payout namecoins too.

This are the arguments everyone likes very much. Your opinion in other words:

"We can cheat everyone, who doesn't care about it!"

I hope every pool operator puts his cards on the table, to see who is not informing his miners about what is done with the miners shares on the miners payed electricity.

Well, i don't like to be scammed!

[ahitman]

Here's one reason the rate is high: https://bitcointalk.org/index.php?topic=42667.msg566146#msg566146  who knows if the other pools are doing it too.

[ajareselde]

I dont understand why do even mine in btc-only pools, when u earn much more on merged mining pool..

If they wanna give away their nmc coins to pool operator whos back mining merged, thats fine, serve them right..

cheers

[teukon]

This is most likely due to the operator of a large pool using all the hashing power for merged mining but only paying out the Bitcoins.  Any miners with a standard Bitcoin pool are expecting a certain payout in Bitcoin for their hashing power.  Starting merged mining at the pool does absolutely nothing to change this (aside from possible a little server downtime) and so is a good opportunity for profit.  If miners actually want the namecoins then there is a selection of pools which payout namecoins too.

This are the arguments everyone likes very much. Your opinion in other words:

"We can cheat everyone, who doesn't care about it!"

I hope every pool operator puts his cards on the table, to see who is not informing his miners about what is done with the miners shares on the miners payed electricity.

Well, i don't like to be scammed!

Don't put words in my mouth!

I would guess that most people mining at a standard Bitcoin mining pool are expecting a "fair share" of Bitcoins for their hashing power.  By using the hashes to generate Namecoins I would argue that a pool operator is doing nothing to change this.  I fail to see how any cheating or scamming is going on.  No rules are being broken and no fraud is taking place.  If a miner doesn't care about namecoins then this is a non issue.  If a miner does care then they might consider using a pool which pays out the namecoins too; it's a free market.

If a miner actually has a moral problem with Namecoins (but not with Bitcoins) then there could be something to this but I honestly feel that most of the comments here are driven by personal greed and envy.

I dont understand why do even mine in btc-only pools, when u earn much more on merged mining pool..

If they wanna give away their nmc coins to pool operator whos back mining merged, thats fine, serve them right..

cheers

There are several reasons.  Low variance, reputation, reliability, lower risk.  Honestly though, with BTC income close to electricity cost for most and with merged mining offering a greater than 40% income bonus I would expect most people to try merged mining.

[Schwede65]

I need to finish GUI for NMC support, then I'll also start giving away all those mined blocks (already over 100 NMC block mined during my tests) back to pool users to spread Namecoins between people.

Btw first merged mined block ever was #148744 (BTC) == #19274 (NMC)

Here is the solution:

slush has tested merged mining with his pool...

rising up of the "missing" 100 blocks...

he will spread NMC between his miners...

[DeathAndTaxes]

Is it impossible to detect? Because the way it works is that the pool pushes to the miners basically a hash of the block transactions that need to be signed, and the miners try to generate a valid hash on the hashed data that they received? But maybe you can detect that the nonce range is fishy, because the nonce has to contain the hash of the namecoin block? If it's impossible to detect then the only way for a miner to avoid being cheated is to use one of the merged-mining pools?

There is nothing "fishy" about the nonce range.  It is still 2^32.

The namecoin data isn't in the nonce range it is in the block transactions itself.

There may be other ways to detect it but it won't be by looking at the nonce.

[BitterTea]

The very simple solution to this is for people to move away from pools that do not officially support merged mining. This will put pressure on the pools that do not (and perhaps are "cheating") to officially support it.

Problem solved.

Also, could this discrepancy not be explained by merged solo miners?

[DeathAndTaxes]

Don't put words in my mouth!

Nobody has to.  You believe pool operator secretly mining namecoins uses miner's hashing power and keeping the profits to be SUPER DUPER OK!

99% of people would consider that cheating.

If a pool want to keep the NMC that is fine but they should announce it.  "We pay you 100% of the BTC and keep 100% of the NMC".   To do it secretly is stealing.  They are stealing the hashing power of pool users.

If a miner actually has a moral problem with Namecoins (but not with Bitcoins) then there could be something to this but I honestly feel that most of the comments here are driven by personal greed and envy.

Yeah and greed has nothing to do with merge mining, not telling your pool participants and keeping the namecoins.  At current rate that works out to a 28.5% pool fee.  Miner's aren't being told they are giving 28.5% of total revenue to the pool operator.

[DeathAndTaxes]

Also, could this discrepancy not be explained by merged solo miners?

Some of it likely is.  But I doubt there are 350GH/s worth of solo miners who also implemented merged mining this early.    Some of it is likely some adventurous solo miner but I doubt all of it is.