Topic: [XCT] C-Bit - Elegantly Solving Bitcoin's Blocksize Problem [SHA256][POW] - page 17. (Read 66801 times)

C-bit is currently deciding on what to do about the coins and its’ own future.

We are discussing matters relating to the unusual pattern observed in our hash rate between Wednesday of
last week, where a gradual increase in our hash rate from 600-700 TH to 4-5 PH occurred over 36 hours
( this was done gradually so as not to affect the difficulty rating ) and then was suddenly and instantly
removed at 12:00 noon EST on Friday of last week just before the difficulty was to reset from 40 Million;
which then set in motion the collapse of the hash rate over the weekend.

Then on Sunday morning at appx 9:00 AM EST, when the hash rate had collapsed aprox 98% from Friday’s
Peak , C-bit’s mining pools had dropped to about 200 TH, and the difficulty level had reset from around 40
million at Friday’s peak to 2 million, a sudden mining onslaught of 2-3 PH began. Although this might not
sound like terribly much; however, coming from such a small hash rate base and against a new small
difficulty rating, its like a nuclear bomb going off. This mining blast lasted thru early Monday morning ( about
36 hours ), which resulted in the basic destruction of the C-bit system. The blast of mining was designed to
last just long enough to take advantage of the difficulty reset of C-bit. The difficulty level has since reset
upward and the miners have quit. At one point during this onslaught, the source code was actually mining
into the future by up to 8 hours, which we all know is impossible; unless, of course, one is a hacker using a
bug in the code and the vulnerability of the system against us. We have proven this to be the case with the
attack over the week-end on C-bit : a deliberate full-frontal crash of our system and resulting doubling of our
system’s coins.

Understand, this was not a weekend guy out for a stroll. This was a deliberate act of violence against C-bit.
Considering the price of our coins, and the illiquidity of the coins, there is no plausible reason for amassing
The quantity of coins gained in the attack, other than pure maliciousness or intent to destroy.

Raise the bar without raising the difficulty, then pull the legs out from under it. Let the momentum pull it
under water, then when the system resets lower, take advantage of it and mine it like crazy. When it resets,
like it did last night, stop mining, like they have. When it resets lower again, mine it again. Destroy the coin
from within. Use the coin’s low hash rate, low difficulty, and its’ very system against itself. Be enough of the
the system, and you own and control the fate of the system. You can drive it into the ground by mining all of
the coins. The attacker is using the 51% rule against C-bit very effectively each time the hash rate drops and
the difficulty rating resets lower.

It sure seems as though it was well planned to destroy C-bit; or if not to destroy, or planned, at least it can be
described as pre-meditated behavior to take advantage of a situation, since no-one could have NOT possibly
realized what was happening when you’re watching millions of coins flying by on your screen... and you don't
shut your miner OFF; especially if you care about the coin and the community. So, it can ONLY be described
as predatory behavior on the part of anyone mining at the time. PERIOD. I would love to hear anyone explain
to me with a straight face their reasoning behind the morality of receiving or keeping after-the-fact any of
their coins in this situation, EVEN if they spent BTC to mine it. Overall supply reasons also make it hard to
justify just shifting coins around to special accounts or just destroying some coins but not others. If the coins
stick around, it just creates more drag on the value of the overall coin that shouldn’t exist in the first place,
since they weren’t fairly earned. I am not sure if we can just keep destroying coins after each of these attacks,
it will get a little silly after awhile.

We also realize that there were innocent by-standers caught up in this weekend’s events. People or miners
Who had nothing at all to do with the events swirling around the exploding coins. I, for instance, have an
Antminer7 that has been running on a C-bit pool since the beginning. An Antminer7 is a relatively
Top-of-the-line Bitcoin miner. Well, I’m sorry, I guess the $ 20 in mining electricity costs over the week-
End, that it cost me for the coins I got, will mean that I don’t take my family to McDonalds tonight. My
machine is run in an off-site location, managed by a third-party, so I couldn’t just shut it off. Morality
reasons dictate that it is awfully difficult for me to justify keeping my coins. Frankly, anyone jumping on
the band-wagon over the weekend and paying for a whole bunch of hash power to mine the coins does not
have my sympathy.

What we find very interesting with this whole situation is that we can trace the beginning of the recent
Cascading of events to last Wednesday morning after the world-wide PR announcement of C-bit.  The
Gradual ramp-up of PH power can be traced to farms in China. The interesting fact is that we have no record
of any interests in either our website or our pools by the Chinese prior to this event; they just showed
up, ramped up, then suddenly left right before the difficulty was due to reset.  How they knew, we don’t
know. They then showed up again after the difficulty reset downward Sunday morning, but with smaller
mining power.

The problem that C-bit finds itself in today is the community is shell-shocked. The C-bit pools are now
Down to 28 TH as miners sit on the side-lines awaiting the dust to settle. The reasoning behind this is
Sound, but the consequences are stark. This sets in motion another cascade of collapsing hash rates and
Resetting difficulty levels. Again, this will bring in the malicious predators who will “Wash-Rinse-Repeat”
Their behavior against C-bit in a never-ending cycle; which is the very thing they want to happen, and
Plan to happen, with C-bit.

Let me repeat. This sets in motion a repeat pattern. Without enough miners supporting C-bit now, because
Everyone is shell-shocked, the pattern will continue until there are no more coins to mine. It’s a compete
failure of the system due to the 51 % Rule and the attackers know that, and they feed off of that loop. If you
look at the source code, you can see what is happening in real time. The attacks will happen again, it’s only a
matter of time.

It removes C-bit from the playing field and removes C-bit from the very reason it was created: to help
Bitcoin Core and Bitcoin Classic resolve their Block-size problem. What was started with good intentions,
Is now dazed and confused, wondering what the hell just happened. We can’t help wonder if there is a
Connection between the sudden Chinese farming interest, the manipulation of our hash rate, and our sudden
destruction. I’ve always hated coincidences -- considering how smoothly everything was running for C-bit in
the 5 weeks leading up to last Wednesday and the world-wide announcement of C-bit. We were fine until
Wednesday, then destroyed by Sunday.

We will decide what our options are after analyzing who and where the attacks originated from, of which we
already have a basic understanding. We will continue debating the future of the mined coins over the past
weekend, and the future of C-bit.  After this decision, we will let the community know our decision.
Hopefully, everyone will agree, no matter how radical our decision turns out to be.

Thanks for your patience.

fool look at these blocks (diff = 1.0 )===>

54950   2016-03-22 17:01:46   2   990   1.0   27475500   68.5573   30.4018%
54949   2016-03-22 16:41:34   2   990   1.0   27475000   68.5433   30.4289%
54948   2016-03-22 16:21:23   2   990.01024709   1.0   27474500   68.5293   30.4561%


per : http://cryptobe.com/chain/CBit
====================

what else do you call this?>>> could it be a classic timewarp type attack ...hmmm ?

yup checked it yesterday and it was a strict ~10min/block
hope good news will be posted here with enthousiasm like Martins58 did before

yes if someone wants to spend a couple thousand dollars, its possible.

btw: c-bits blockchain looks fine now.

If there is not enough power spread on pools,this could happen one more time?

actually that quote gembitz posted is from 2011 lmao

the difficulty went down and then someone mined with a 1+ ph/s rig. there was no timewarp, just a 500% attack..  i looked at the source code, its identical to the newest bitcoin source code. what happened here could happen to bitcoin, if enough hashpower hit it. from what i read, farms do shut off before difficulty retarget and then turn back on when it switches if its lower. 1 difficulty blocks are to make sure that at least 6 blocks get released per hour. if there are only 5 and an hour approaches, a block with a difficulty of 1 is released. :yawn:

the said [ 51% / timewarp ] is obvious ~ just look @ those 1.0 diff blocks ...stay tuned 

@gembitz So if the attack was a time stamp one and not 51% we can say that toronto held coins must be released because it was no attacker there.
Another thing is,watching the block explorer we can say that the attack is not over yet as there are always 1diff blocks generated again and again and if it not will stop,diff will return to 1 one more time

lol..imo the underlying integrity of the code dictates results!

===> you wanna see 10 PH? ~ i'd have you all in tears   j/k


+just look at the attackers ability to get blocks w/ diff of ~ 1.0
----------------------------------------------------------------

>>>>>>>>>>>>>>>>>>>>
" Time warp attack

The time warp attack[1] is based on a bug in Bitcoin and Litecoin (and their forks) where the difficulty calculation is off by one block. This is an example of a flaw that affects all coins, especially ones with low network hash rates.

An attacker can repeatedly try to generate the last block of each retarget window, and use a fabricated timestamp of two hours into the future in order to make the time difference from the first block in the retarget window high, thus lowering the difficulty by 0.5%. Due to the bug, the bogus timestamp isn't used as the first block in the next retarget window, and therefore the two extra hours aren't being compensated for in the next difficulty calculation. Once the difficulty is low, the attacker can mine many fast coins, or in the case of a small chain, an attacker with 51% hash power could reduce the difficulty to 1 and mine a new fork from the genesis block.

This attack may not be as feasible on Bitcoin any longer because the probability of repeatedly generating the last block once every two weeks at such high difficulties may be negligible.

Although fixing this issue in Bitcoin is possible, it should be done carefully (by adding rules that encourage nodes to upgrade over time) so to avoid a chain fork, i.e. old clients who didn't upgrade might operate with another difficulty and therefore disagree regarding which blocks are valid.  .... "


 


https://bitcointalksearch.org/topic/m.521772



ArtForz
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Re: Possible way to make a very profitable 50 plus ish attack for pools?
September 12, 2011, 09:39:28 PM
   
Reply with quote  #6
Erm, no, those blocks are *valid*.
By exploiting the fact that retargeting ignores one block interval every period, it's possible for an attackers' fork chain to "jump backwards in time" and create lots of blocks at low difficulty without running nTime off into the far future.

Bitcoin (and most *coin) rules re. block timestamps:
nTime has to be > median of prev 11 blocks.
nTime has to be < now() + some buffer.

let's say we have a chain with 4-block interval and 10 sec/block.
Official chain, currect diff for hashrate, blocks found at nominal time:
Code:

blk#  0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15
time  0  10  20  30  40  50  60  70  80  90 100 110 120 130 140 150

Now here's the weird part, we retarget after blocks 3, 7, 11, 15, and for block 3 we use 0 as first and 3 as last, for 7 we use 4 as first and 7 as last, ...
so what happens if an attackers chain has blk timestamps like this:
Code:

blk#  0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15
time  0   1   2  30   4   5   6  70   8   9  10 110  12  13  14 150

?
first period (#3 - #0) is 30s as before
2nd period is (#7 - #4) ... 66s
3rd period is (#11 - #8) ... 104s
Whoops.
Obviously this ignores the "problem" of the attackers chain having way lower sum-of-difficulty
but thats easy to fix:
Code:

blk# 16 17 18 19 20 21 22 23 ...
time 16 17 18 19 20 21 22 23 ...

just keep driving diff up at maximum speed until you have the same total work as the real chain.
result-> the attackers chain does not violate the block timestamp rules, finishes at a *earlier* block timestamp than the real chain, ends up at a higher total work as the real chain, but contains way more blocks.

This was done on the GeistGeld chain yesterday/today, so it's not a theoretical problem














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see?

Anderson answer me this please. Did u start mining with your hash power in NY and then came to join me in Toronto?? Or u never mined in NY, u saw the diff drop and joined me in Toronto after and increased your power gradually. This is important information for this case.

It will take some time, patience is the key.

i apologize and forgive me if i done anything wrong to
everyone. the incident already happen when i mine with
other, so right now look like i am the only one to blame for.
again i want to say i apologize and forgive me.

i want to donate all my coin, half to DEV, half to Mr Martens.
without these two person the coin getting nowhere.

please try to lived in kindness and peace, the good thing
will come to you.

how is everything going dev, or we on schedule to release
the bitpay and something else ?

are you still with us Mr Martens ?

ps. i could buy a few hundred thousand coin
i dont want to be bless for 18360 coin.

i like your story MTNMINER,

if i am not mine that time, who we going to blame for
a dog, a cat, oh no there a little mouse at corner let blame him

looks like the coin generation has slowed down significantly, let's see the price reflect this soon..tbc 

hi there Martens, i seen you back, make me worry when we have not heard
from you for awhile

i think they mean the guy who added 1+ ph/s

These miners should not leave empty handed, that's for sure, they deserve their rightfully earn coins. If not all of them out of fear of them crashing the market, then at least a more than fair amount.

Please kindly clarify how I could have done an attack with 250TH/S?

yessir +1