Deepbit hopping - page 3. | Bitcointalksearch.org

DeepBit

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Quote from: P4man on February 07, 2012, 12:55:10 PM

Quote from: DeepBit on February 07, 2012, 12:48:19 PM

I don't think that those 115% schemes gain their profit from hopping deepbit because it would be really obvious for me.
I noticed a couple of times when some user bought a "contract" from GPUMAX and tried to use it for hopping deepbit, but I prevented it.

If no one is hopping deepbit, the above graph would look different.

As I said, there are hoppers and I'm working on this.

Quote from: P4man on February 07, 2012, 12:55:10 PM

Quote

As for your graph, yes, there is some correlation, but you should show full range from 0 speed for axis Y

Why? Zero would mean a block thats never been found.

I was talking about the axis range.

Quote from: P4man on February 07, 2012, 12:55:10 PM

Also can you please tell me how the duration in the stats is rounded?

Why don't you just use the first column with timestamps ? It's 1-second accuracy there.

P4man

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Quote from: DeepBit on February 07, 2012, 12:48:19 PM

I don't think that those 115% schemes gain their profit from hopping deepbit because it would be really obvious for me.
I noticed a couple of times when some user bought a "contract" from GPUMAX and tried to use it for hopping deepbit, but I prevented it.

If no one is hopping deepbit, the above graph would look different.

Quote

As for your graph, yes, there is some correlation, but you should show full range from 0 speed for axis Y

Why? Zero would mean a block thats never been found.
Someone better in statistics than me can do the proper math, but it looks to me like ~10% of your hashrate is successful hopping.

Also can you please tell me how the duration in the stats is rounded?

DeepBit

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I don't think that those 115% schemes gain their profit from hopping deepbit because it would be really obvious for me.
I noticed a couple of times when some user bought a "contract" from GPUMAX and tried to use it for hopping deepbit, but I prevented it.

As for your graph, yes, there is some correlation on it, but I think it's a bit off because randomness should also cause the speed to be lower sometimes for the lucky blocks. Also you should show full range from 0 speed for axis Y :)
EDIT: new graph is better.
Usually they are hopping with some delays, so shortest blocks are not affected after long enough ones.
I know that there are some hoppers and I know that stats delaying is not safe enough to prevent it, but their effect on innocent miners is not so noticeable because they just don't have enough hashing power for this.
I'm working on automatic countermeasures and I have ready detection routines that are undergoing testing at this moment.
Some users already noticed that: https://bitcointalksearch.org/topic/m.718043
I'm collecting results to ensure that no false positives will ever happen, then automatic punishing can be enabled to protect my users.

Additionally, hop-proof payment method may be implemented later.

P4man

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Recently there have been various 105-115+% PPS schemes propping up.
The most sensible explanation I could see was pool hopping large proportional pools like deepbit.

Deepbit delays its stats by an hour, but I didnt think that would be enough to prevent pool hopping, since deepbit is so large, you might assume every new block that is found, is found by deepbit, and you'd be right 1 times out of 3. Good enough to extract a profit from the non hopping proportional miners.

So, I decided to have a look at deepbit stats, to see if I could find evidence of this theory. I collected the stats for last 5 days and plotted the estimated hashrate against block duration. And sure enough, there is a nice correlation:

edit: this graph is incorrect, see below.

X axis shows minutes it took to find the block, Y axis is estimated hashrate (shares / minutes).
Average is 24.7 minutes.

I discarted sub 2 minute blocks, but even so data for the shortest blocks are not to be trusted, since deepbit only gives a granularity of 1 minute. Moreover, I do not know how the lenght is rounded, so if 1m59s becomes 1 or 2 minutes. This could also skew the graph, but I dont think enough explain the correlation.

edit:
Deepbit rounds 1m59 seconds to 1 minute in the stats, so on average I would have to add 30 seconds to each block. Then we get this graph

X axis shows the minutes it took deepbit to mine the block (average is ~25).
Y axis show estimated speed (shares / time).

Correlation is much less strong, but its still there. Looks like almost 10% hoppers.

~~Tycho, can you shed some light on this? Or if you can, provide data thats more accurate than 1 minute?~~

Topic: Deepbit hopping - page 3. (Read 6132 times)