How is a 51% attack detected?
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How does one know it is going on? I was just tooling around a little bit looking at the pools (that I know of/listed on CoinArmy.com’s feathercoin pools list). I was curious where all the current hash power was sitting. Adding them all up the best I could see was about 30ish % of the current network hash rate reported on stats.feathercoin.com.
Either someone is getting really lucky, something weird is going on, or I just don’t know how anything works (very possible).
I ventured over to cryptocoinexplorer.com and looked at the last block according to stats.feathercoin.com (39127 when I started looking) and then clicked on the address the block reward went to. I thought it was strange to see that many block rewards going to one address…all starting today with block number 38854. EDIT: especially that many in sequence.
My question for the more knowledgeable is…is this normal, weird, or just plain lucky?
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One indication is increased hashrate coupled with increased orphan blocks, AFAIK this has not been reported recently.
I’m on pool that is showing 0kH/S on those stats you are looking at, my miner and pool are A OK!
Wemineftc finds quite a few blocks, they obviously have a wallet to receive payments too.
So you are saying from block 38854 - 39127 [b]all[/b] went to one address? Wemineftc found:
[code]39,054
39,053
39,046
39,037
39,034
39,020
39,016
39,011
39,009
39,001
38,997
38,990
38,970
38,961
38,952
38,936
38,935
38,916
38,886
38,880
38,867[/code]It’s just normal. 8)
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i’m looking at it also its weird and I don’t know this address. coinortron was nearly down for 1h 1 hour ago. and the 6tnEmAwtUAv3a7WbvYgo4oowcE5MDJ3fHL is getting nearly 50% of the blocks.
6xtJbibr23Y4PDPz2kENxszHNGyfo5exsJ ---- is coinotron
6zFxrWjwCSzoPNZFudvSVCpBYV9nQTWGdr — is we mine FTC
6po4AjgPBz8HEkJKFfaBD5fTYy7yNdH4gi – seems a pool
72vgxAEptKghVXSESDhgemmtQXcSD5udce – is FTC is a geek
6uNcx3XPvcgToBPeGnxqqx4vk9r4ovoNBp - seems also a pool38864 -39144 (280) he got 125 blocks with some gap in range that can be badluck or just a stop of mining especially true in the pre retarget(where gap are bigger then after retarget).
he mine and i don’t see orphan chain so far that are not normal (1-2 occurence of 1 ophan block with time range that seesm to indicate a legetimate orphan and at least one was done by coinotron not this address)
what it is? A profit swap pool, the attacker, a FTC pool i don’t know about and not list?
most likely not a pool as no payout have been done.
so need to keep watching.51% is one thing
51% attack is 51% with fork chain, but in itself just very annoying and miner lost the money from what should have been the real chain.
51% attack with malicious activity is the real attack (double spend, time change, etc.)so we currently have someone at 51% or near 51%. no 51% attack as far as I know
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Hi UKMark…thanks for the response! To be clear I’m not trying to single anyone out for nefarious activity…I just thought it odd and wanted to ask those that know.
[quote name=“UKMark” post=“16866” timestamp=“1371850889”]
I’m on pool that is showing 0kH/S on those stats you are looking at, my miner and pool are A OK!
[/quote]
To be clear, I didn’t add up or use the stats page I referenced as it doesn’t match up anyway. I added up the pool hash rate reported by each pool manually and they aren’t anywhere near stats.feathercoin.com network hash rate. (sampled: coinotron, d2, FTCisageek, featherpool.ru, hynodeva,multipool,nut2pool, wemineftc {where I am mining BTW}, and give-me-ftc). They all added up to around 1 GH/s unless I seriously typoed.
[quote author=UKMark link=topic=2121.msg16866#msg16866 date=1371850889]
Wemineftc finds quite a few blocks, they obviously have a wallet to receive payments too.
[/quote]
Yeah, I get that. But I’m sure wemineftc’s wallet has transactions from before 21 Jun 2013, and also has payments out. The address I’m looking at does not, yet, unless I am interpreting this information incorrectly.[url=http://cryptocoinexplorer.com:5750/address/6tnEmAwtUAv3a7WbvYgo4oowcE5MDJ3fHL]http://cryptocoinexplorer.com:5750/address/6tnEmAwtUAv3a7WbvYgo4oowcE5MDJ3fHL[/url]
[quote author=UKMark link=topic=2121.msg16866#msg16866 date=1371850889]
So you are saying from block 38854 - 39127 [b]all[/b] went to one address? Wemineftc found:
[code]39,054
39,053
39,046
39,037
39,034
39,020
39,016
39,011
39,009
39,001
38,997
38,990
38,970
38,961
38,952
38,936
38,935
38,916
38,886
38,880
38,867[/code]It’s just normal. 8)
[/quote]Not quite. I get that luck brings blocks to the same place sometimes. My short experience with crypt though hasn’t seen a case where so [i]many[/i] sequential, or very nearly, blocks are found by what looks like the same recipient.
example:
[code]
Block Approx. Time Amount Balance Currency
39127 2013-06-21 20:28:51 200 23401.82095209 FTC
39129 2013-06-21 20:36:41 200 23601.82095209 FTC
39130 2013-06-21 20:43:42 200.12 23801.94095209 FTC
39131 2013-06-21 20:45:51 200 24001.94095209 FTC
39133 2013-06-21 20:56:29 200.005 24201.94595209 FTC
39138 2013-06-21 21:06:34 200 24401.94595209 FTC
39139 2013-06-21 21:07:09 200 24601.94595209 FTC
39140 2013-06-21 21:07:40 200 24801.94595209 FTC
39143 2013-06-21 21:17:46 200 25001.94595209 FTC
39145 2013-06-21 21:21:33 200 25201.94595209 FTC
39146 2013-06-21 21:25:48 200 25401.94595209 FTC
39149 2013-06-21 21:35:37 200 25601.94595209 FTC
39150 2013-06-21 21:38:56 200.01 25801.95595209 FTC
39152 2013-06-21 21:43:37 200 26001.95595209 FTC
39154 2013-06-21 21:46:23 200 26201.95595209[/code]I point out block 38854 as that is the first block showing for this address.
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[quote name=“groll” post=“16867” timestamp=“1371851226”]
i’m looking at it also its weird and I don’t know this address. coinortron was nearly down for 1h 1 hour ago. and the 6tnEmAwtUAv3a7WbvYgo4oowcE5MDJ3fHL is getting nearly 50% of the blocks.[/quote]
That’s what I thought was so stand out too…especially that there isn’t any transaction history [b][i]before[/i][/b] today’s date. Such a stiff jump in hash rate from where we were before the difficulty change today is what I thought was weird. During the last crazy days, when hash rate was high, folks were complaining because the pool’s hash rates were getting close to 51%. That doesn’t seem to be the case today so I thought I would/should bring this up for discussion.
EDIT: P.S. I only started looking myself out of curiosity of where all the hashes were coming from. I don’t [i]know[/i] if it is a big deal and I don’t necessarily have an issue with someone getting lots of blocks. I also just thought to ask in case it is a pre-cursor to 51% [b][i]attack[/i][/b]
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I see your point now looking at that addy in more detail, by my calcs they have just shy of 1.5gH/s - :-\
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[quote]EDIT: P.S. I only started looking myself out of curiosity of where all the hashes were coming from.[/quote]
it’s also where I started … just a month ago ;)as i follow the hash and chain a bit evryday I know that coinotron is usually near 40-50% so when I see coinotron at 500K and the network at 3G I started to look at who found the blocks. but more importantly for fork. and found nothing of interest on fork (interesting fork for [i]possible[/i] double spend: usually have large cash involved and are 5-6 or more block orphan long so confirm to an exchange or merchant would be set as completed, then reverse with a new chain)
we don’t have this so far.
51% don’t mean higher hash rate in all case just that the attacker use the hash rate to get a longer chain so one more block for a time period is enough changing orphaning a 9 block by using a 10 block would only had 10% hashrate in the stat for those 10 block. hashrate is not mesure it’s a calculation from block range- time -difficulty. in reality the attacker will need more then the 10% shown but >50% to make the attack and orphan the 9 block chain.
if that address would do 51% attack for double spend our hash rate would in fact slow down as he will need to mine the new chain on the side.
Edit: if for like last time play for the time it would need to keep all the block for himself in the chain so orphaning all block found by others as they would set the right time. in this case the hash rate would be lower then now as orphaned block would not be counted and only the attacker hashrate would be used in the chain(need to be counted with real time not manipulated time as this can give very high hash rate)
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[quote name=“groll” post=“16877” timestamp=“1371853601”]
[quote]EDIT: P.S. I only started looking myself out of curiosity of where all the hashes were coming from.[/quote]if that address would do 51% attack for double spend our hash rate would in fact slow down as he will need to mine the new chain on the side.
[/quote]thank you for that clarification.