Bitcoin Forum

Well, I run a pool as some people know :)
I've also been involved in bitcoin for a little while (since July-2011)
and I also write some code here and there.

Anyway, yeah I do have some interest in BTC and I'm not really fond of those who do things that at least I think are bad for Bitcoin.
I've inferred same rather interesting information about SPV mining that may be of interest to any pools out there who also think it's bad for Bitcoin.

One of the details (though many probably already know this) are that: SPV pool simply run a miner to other pools that (what I'd call a 'dead pool miner') listen for block changes and uses that info to generate a new unverified empty block header and then distribute that to their pool's miners through their pool work distribution.

There are other methods that will produce the same result later, but that's the greatest speed up they can use for other pool's blocks.

If anyone has more information regarding these miners, feel free to post here.
I consider it quite appropriate to out these miners since they aren't even mining (when they 'dead pool mine' on my pool)

IP addresses:
120.55.119.224
123.57.173.63
106.187.94.193
192.155.84.181

They 'address mined' at my pool and were using the address:
https://www.blocktrail.com/BTC/address/1J1F3U7gHrCjsEsRimDJ3oYBiV24wA8FuV

They made it easy for me to determine this coz all 4 addresses were doing exactly the same thing to the same BTC address
The first 2 are inside the GFW the other 2 are outside

Edit: I updated the address as a link in case anyone didn't realise the significance :)

You have been moved to our blacklist. You will not see these IP addresses connecting to your pool and waste your pool resource anymore. Thanks.

Fun to see the a pool that is _DOING THE WRONG THING AND HURTING THE NETWORK_ is "blacklisting" somebody.

So, is that an official f2pool stance - blacklisting any pool that actually contributes to the Bitcoin network?  ::)

To make it easier, why don't you just make a whitelist of pools that SPV mine & use only them instead of leaching off every pool/node that cares & contributes towards the network? That way, you'd be doing us all a favor.

@macbook-air
Do you mean that you'll intentionally not build on blocks from Kano.is? I think you need to clarify what you mean by blacklist.

We will not build on his blocks until our local bitcoind got received and verified them in full. This guy leaked our IP addresses to the public, I pm him kindly and begged him to remove them but he refused. If we ever got DDoSed due to his post, we have no choices but point our domains to his pool.

Your welcome.
I have reasonable DDoS protection.
Funny you consider that your only option - clearly you have no idea how to deal with network problems :D

As stated above, they were the IP addresses of miners mining on my pool but withholding doing any work and using my pool to help SPV mine.
I obviously do not want miners doing that on my pool.
No one asked, (I would have denied it), thus the results.
Interesting that you consider them important, you use these IPs to SPV "dead pool mine" on competitors pools with important IP address?!? ...

You also said to me in PM, after I worked out what was going on, that it is to "reduce my orphan rates" and thus to my advantage to let you SPV dead pool mine on my pool ... ... ... ...
Edit: and said that I don't care about my customers who mine on my pool getting more orphans because it wont cost me since my pool isn't PPS ... ... ...

Clearly we have a different idea about the term "advantage" and what is good for Bitcoin.

While we are at it, I will also point out fake excuses spread by SPV mining pools:
One of the excuses given was because it is often slow to distribute blocks through the GFW, so they are at a disadvantage.
In a peer 2 peer network, if you divide the network with a line, the side of the line with clearly less power is at a disadvantage.
With the GFW, the side of the line inside the GFW has the higher network hash rate ... ... ...

You'd point your domains to HIS pool if your being DDoSed? Even if someone DDoSed the IP addresses? :)

You guys are quite a sizable pool, so why do you feel it right to mess with competing pools in that way? I think this should be stickied because one of the major pools trying to do this to smaller pools... Might convince some miners to jump ship who don't appreciate this sort of thing. I don't mean to be rude, but this has been handled very badly. Not trying to start a flame war, but to fiddle with competitors pools in that way and then threaten to divert any attack from your domain to their pool, doesn't that make you as bad as the DDoSer themselves? This is not what satoshi would have wanted at all, all mining pools and solo miners alike are in this together. Fiddle around with not building on blocks from certain pools (even though you are not doing that) for example is one way to risk the stability of bitcoin and then crash its value making the currency and your equipment worth less.

Just my two cents...

IP addresses are in the public domain, view-able by anyone - you can't "leak" something that is already public knowledge.

Threatening to divert any ddos attack to a different pool is completely & utterly wrong. It's immoral & disgraceful, you should be ashamed of yourselves - or is this a common tactic employed by SPV mining pools?

This is what happens when a pool that contributes nothing to the Bitcoin network gets too big, they resort to playground bully boy tactics & statements in the false belief that they are somehow invincible & can do as they please. If I were a pool operator I would have no problem banning IP addresses from all SPV mining pools from connecting to my node & encourage every other pool or wallet owner that cares about the Bitcoin ecosystem to do the same.

Thank you kano for helping to bring this to everyone's attention, the more people who realize the harm these large SPV mining pools do to the network - & the lengths that they will go to to damage any other pool that questions them - the better, safer & healthier the network will become.

Edit: Deleting posts from your own thread regarding this won't help either.

The badly named "SPV mining" is not that bad for bitcoin.  In fact it is better than the alternative

• An empty block buries the earlier ones under a chunk of hashwork, and thus helps secure them against tampering, just as well as a non-empty one.
• You *want* other pools to do SPV mining on top of your blocks, to reduce *your* orphan rate.
• You *want* to do SPV mining yourself when you learn that someone else just mined a block B(N).  The alternatives are (a) keep mining your own version B'(N) of the same block, in the hope of solving it just a few seconds later and getting it accepted by the network in place of your rival's; or (b) keep your equipment idle, or turned off, while you wait to downlad and verify that full B(N).  In both cases you will be hurting yourself, your member miners, and ultimately the network (by wasting some of your hashpower).
• SPV mining is not particularly unsafe, because the pools have no interest in broadcasting bad blocks to their members.  The pools who do SPV mining are making a calculated bet, based on the trust that their peers deserve, and will be punished if they trust a parent that turns out to be invalid.  (The "Fork of July" that followed the activation of BIP66 was the fault of the Core devs, who tried to do a stealth change in the protocol and bungled it.)
• SPV mininng does not really reduce the capacity of the network. Rather, it is a consequence of the limited bandwidth available for block propagation.  If SPV mining was suppressed somehow, instead of empty blocks there would be longer interblock delays and/or a reduction of the effective total hashpower compared to the total available hashpower. The empty blocks are just an embarrassing symptom of the limited capacity

Think of the miners as producers of a continuous stream of hashwork, like toothpaste squeezed out of a tube -- the blockchain -- with transactions being secured by being embedded in that stream.  Empty blocks are a length of that stream  that gets appended to the blockchain with no transactions embedded in it. If SPV mining were suppressed, in an attempt to fit more transactions in the stream, one would simply get a reduced hashwork output (because of longer block waits and/or lower difficulty setting).  So the max transactions *per unit of hashwork added to the blockchain* would be the same.

SPV mining could be suppressed by a protocol change, if desired: make the Merkle link (block hash) from block B(N) to B(N-1) depend on the contents of both blocks, instead of being just the hash of B(N-1); in such a way that the link cannot be computed by the miner that sets out to mine B(N) without knowing the full contents of B(N-1).  But that would probably not increase the effective capacity of the network, as said above.

Whoa

WOW, you may hide behind Chinese hacking BS laws...  but that is clearly a blatant threat, and against US laws....      I would suggest forwarding it on to the appropriate authorities.

I hope the network will be able to recover from being this hurt. TBH I didn't even know it had feelings in the first place.

All false arguments from someone not actually involved in mining. We've proven that we can do block changes about as quickly as the spv mining pools yet with fully validated blocks and transactions. The SPV mining pools caused a fork they built on for a few blocks earlier this year due to mining on unvalidated block headers from other pools and more than one pool kept on bouncing broken blocks between themselves before finally having to wind back to the correct blockchain. If that's not wasted hashrate i don't know what is. With the size of the pools in question (>50% of the network combined), it could have gone on indefinitely had they not noticed.

I deliberately held off replying to his post as I not only didn't know if he was a miner or not, but also in the hope that someone who is more knowledgeable than me in the field would chime in.....and you did - thank you  :)

Sorry, but you sound like a little kid. Actually, all of the IPs were publicly known and everybody who was interested to kno was able to link these IPs to your pool.

All that happened was that Kano found you with the hand in the cookie jar. So stop whining.

Just thought I'd quote that in case he decides to delete it :)

Wow ...

--

Bitcoin devs dislike me coz I'm too coarse in my criticism of them, but I will say I don't know of any bitcoin dev who would agree with that statement and disagree with me on this one.

Seriously, get someone of any knowledge and reputation in the bitcoin world to come here and post agreement with your statement.

I'd wonder if you could find anyone.

I had someone ask me about this in PM

I'll post my reply to him (obviously not include his question with this name) so that anyone wondering about what I think is wrong with SPV mining understands my stance on the subject.


and


--

... and my last PM to f2pool in case anyone was wondering what I was saying about it:

I knew you were a lowlife, but you have redefined the word lowlife. You threatening Kano is a threat to many people who will stand with Kano.
You have threatened too many people.

You think you are above the rest of us because you are involved with the group who run F2pool / discus fish.
You are not above anyone. You are equal to a scammer in my opinion and not only because you continue to put the bitcoin network in a precarious position with the decisions you make, because of your self-righteous attitude acting like a spoiled child.

It is easy for you to hide behind your keyboard and make threats now, but it will not always be so easy.
Your immaturity rules you, your temper has defined your way of thinking, and greed has completely muddled your sense of self-worth.

Greed will only be the motivation for mining at your pool for so much longer. When you begin to wonder why so many bad things begin to happen in your pool, your life, and your demented mind you only need to refresh this page for a reminder of why.

Kano exposed more of the evil actions and choices you make. Even though you are not alone in these choices you have squarely planted the X to your face. There is a core in this community who hold themselves and their peers to a higher standard of life choices. You should evaluate who your peers are and seek help from the core I speak of beginning with an apology for threatening Kano, the people who mine at his pool, and everyone who mines in the bitcoin network.  

Companies have been brought down for much less than what you have done and people for far less yet.

Edit:
Your threats are a shakedown aka extortion. It is the same as making someone pay you, or you attack them. This is akin to a mafia style way of doing business and that is not the way bitcoin should be represented. You, and anyone who continuously associates or mines with F2pool should be ashamed. You have no honor.

Edit #2:
None of us fear your threats.

Surely the SPV mining pools will want to do that, then, if it works.  If it is in their interest to do so...

The bitcoin protocol was meant to work if each miner did whatever was more profitable for him.  If it is necessary for the miners to be "good citizens", then the protocol has faied.  In this case, I do not think it has: empty blocks are not a problem, just a normal consequence of other problems (such as limited bandwidth and excessive block reward).


I insist, it was not their fault, but the fault of the devs who programmed BIP66 to be enabled immediately when 95% of the miners had updated, with no grace period -- thus ensuring that 5% of the hashpower would still be using the wrong rules at the fork time, no matter how quickly they tried to update. 

That 5% of the hashpower would have been wasted anyway, even if the SPV miners had not mined empty blocks on top of that bad one.


One does not need to play football to know exactly where the coach went wrong.  ;D

I was going to formulate a meaningful response to your response but your response is the most vacuous set of comments I've seen in a very long time so I shall leave this discussion as is and let others pass judgement or respond if they feel so obliged.

No coach in bitcoin - sorry wrong forum.
Go visit some sports site where you may have a chance at providing insight instead of ignorance :)

Well, since some may read his post and wonder what is wrong with it, I'll elaborate.

F2pool's name isn't Shirley.

Bitcoin has "good citizen" rules.
Sorry if you felt that you'd found some magical anarchist utopia without rules, you're wrong.

Those rules are reasonably well known - and bitcoin core is an example of where to find them - you should try learning about them one day.

e.g. I can't go mine a zillion, 1,000 difficulty blocks and get 10's of thousands of BTC a day with a 1THs miner.
Damn that's not what you thought is it? Yet that would be more profitable if I did that wouldn't it?

Also, of course, there's the block header requirements, like versions and hash values based on previous blocks and merkle tree hashes of transactions.

... and for those transactions ...
Yep, again, wouldn't it be more profitable to make a transaction that created 1,000 BTC and sent it to my address any time I wanted to?

So yeah, anyone can do those things, but then they are no longer mining Bitcoins and (most? :P) Bitcoin exchanges wont accept their scam-coins

SPV mining allows for their blocks to fall directly into this category.
As I already stated, they don't verify the transactions and merkle tree and ... ...
So if someone did indeed make a block, with a transaction in it that created 1,000 BTC and sent it to their address, and pushed out that block to the SPV pools, guess what? The SPV pools would accept that block and start mining on it.

Yep their method will lead to breaking the rules ... and they have already done so in the past.

Incorrect.

Bitcoin is not set in stone to never change for eternity.
It will, and must, change over time to accommodate the requirements of the majority of the bitcoin network.

With Bitcoin, it has been done via a trigger in the core code that makes the change effective when the requirements exceed 95% of blocks mined over a given history of blocks. That's how it was done for the v3 change. The grace period was the whole period leading up to that 95% acceptance.

A longer grace period would have made no difference to their SPV code.
Their code didn't bother to even check the block version number, so whenever in the future, after the v3 change over, if someone mined a v2 block and sent it to the SPV pools, they could have accepted it and forked the network. Yes it was their fault. Yes, they had updated bitcoin daemons. No their SPV code was wrong.

Sorry, but you got it wrong.  


And that is the point: miners should avoid those things because they are bad for them, not because they are bad for bitcoin.  

That is why it took 20 years to invent bitcoin.  If one could assume that the players would be good citizens who followed the rules, either to go to heaven or because of community pressure, bitcoin would have been invented 25 years ago.  If a misbehaving miner is hurting bitcoin, that is a flaw of bitcoin -- because its essential property, that made it the solution to the distributed ledger problem, is that it does not depend on miners being "good", only on a majority of them being "greedy".


You missed the point completely.  Miners were upgrading their code from v2 to v3.  Since the BIP66 change was programmed to be enabled immediately once 95% of was running v3, at that moment inevitably there would be 5% of the miners still running v2.  

A grace period of (say) 2 weeks after reaching the voting threshold would have allowed warnings to be sent out, and then those remaining 5% would have convert too -- because otherwise they would be wasting their work.  But the devs opted for zero grace period and zero warnings, thus ensuring that some miners -- those who were last to upgrade -- would issue invalid blocks and waste their work.  

Specifically, the 6-block bad branch started when BTCNuggets mined the v2 block after the forking block: not by their choice, not because F2Pool was SPV mining, but because the devs bungled it (and did not even apologize).

(Please don't tell me that the miners should have updated more promptly, so that 100% of them should have been among the first 95% to upgrade.)

Sigh, it is a majority that are SPV mining ... do you even understand at all what that means?

A majority of the network is happy to risk mining on invalid data.
Then what happens? They continue doing it coz they have the majority and the 'invalid' fork they are mining keeps growing faster.

Guess what actually happened?
The v2 fork was growing faster than the v3 fork.
I contacted Bitmain and told them what was going on and they contacted their "pool technicians" and then switched over from the v2 fork some time after that.
Of course, they didn't actually fix it coz it happened again about 20 hours later ...

--

Secondly, seriously go look at the block chain.
The SPV miners were already submitting v3 blocks before hand.

They knew about BIP66 coz they had already upgraded for it.

What they didn't do with their SPV mining was ... ... ... ... check the block version number since they didn't care to do that.
That involved more than they already did.
Guess what, it's prolly gonna happen again shortly with v4 blocks ...
As simple as that. They didn't care.

--

... as for your 5% number, no that's wrong also.
It only means that in the previous 1000 blocks (~1week) there were 5% v2 blocks.
The actual number mining v2 blocks at the time of the change to v3 is lower than 5%
It's not a flat line of no more adoption for that entire week/1000 blocks ...

The lead into v3 also started long before that.
https://github.com/bitcoin/bitcoin/releases/tag/v0.10.0 Released 13-Feb ...

Even Greg, who coined the term "SPV mining", admitted that it was a bad name.  There are three things that go by that name:

• (A) The miner starts to mine an empty block B(N+1) as soon as it gets hold of the hash of B(N), before it has got the full B(N); and publishes that empty B(N+1) if he solves it before getting the full B(N).
• (A2) The miner does (A) even when he notices that B(N) was itself empty, because the other miner was doing (A) too.
  
• (B) The miner does not bother to dowload and check the full B(N) at all, once it got its hash.

Miners will do (A) and (A2) if they can, because the alternative is to let their equipment sit idle or turned off in the interval between receiving the hash of B(N) and the full B(N).  If that turns out to be bad for bitcoin, that is a flaw of the protocol; the miner is not to blame, because he was supposed to be greedy and do what is best for him.

(The protocol could be changed to prevent (A) and force the miners to wait for the full B(N); but then the useful hashpower would be less than the installed hashpower, so it is not clear that it would be better for the coin.)  

Item (A) is not an entirely bad thing, because the empty B(N+1) will still help secure B(N) against tampering.  The miner who mined B(N) *wants* to give its hash to all other miners, as quickly as possible, and *wants* them to do (A), because it helps secure his gain against orphaning.  Every miner *wants* to get the hash of other miners' blocks as soon as possible, and do (A).  

Item (A) is usually pretty safe for bitcoin, as well as for the miner of B(N+1), if he knows that the solver of B(N) is a known real pool: because that pool will lose lots of money and reputation if he sends a bogus hash out to its members.  Choosing to do (A) is a calculated risk by the miner, with a clearly positive expected payoff.  Last July (and in no other occasion that I know of) item (A) failed by magnifying the mistake of BTCNuggets from 1 block to 6 blocks, thus causing monetary loss to F2Pool and AntPool in addition to the loss suffered by BTCNugets.

Perhaps pools will modify their implementation of item (A) now that they know that the probability of other miners issuing invalid blocks is not negligible.  In hindsight, the Fork of July could have been just one or two v2 orphans, rather than a 6-block chain, if the miners had refrained from doing (A) or just (A2), for a couple of weeks around the BIP66 switch-on event; that would have avoided the loss incurred by F2Pool and Antpool (but not the loss of BTCNuggets).

As for item (B), it should not be in the miner's interest to do that, so there should be no need to nag those who do it.  But the expected loss from doing (B) is basically the transaction fees, so it is a weak deterrent.  That is a fault of the protocol and of whoever set the minimum fee so low -- not of the miners.

However, I recall that F2Pool admitted to be doing (B) in July.  They claimed that they had decided to do (B) after having one of their blocks orphaned.  I do not quite understand that excuse; but, anyway, they promised to stop doing (B).  But they also said that they would continue doing (A), for the reason above.  You cannot blame them for that decision.


Failing to check the version number of B(N) was F2Pool's mistake, but that did not happen because they were doing (A).  They easily could (and should) have checked the version when doing (A).  They did not bother to check it because they did not foresee the risk of other pools continuing to mine v2 blocks past the fork.  

That check would not have prevented Antpool from extending the wrong branch, because they mined on top of a v3 block header.  


Maybe not 5%, but the percentage of v2 miners was high enough for a v2 block to be issued just after the fork.

Why is everybody blaming F2pool for mining an empty block on top of that one, and no one is blaming BTCNuggets (and the other miner who did the same 20 hours later) for having produced that block in the first place?


Wait, you are not saying that there was plenty of time for 100% of the nodes to be among the first 95% to upgrade, are you?  ;)

But you can blame them for:
- threatening other pools
- "mining" while withholding
- lying

And so on. While you are playing an academic game - which I sometimes really enjoy - we are here in a situation where a pool operator shows the behavior of a bully - to say it in a friendly manner.

We were not mining and withholding. We just connect to their server and receive what they send me. What they get is just 4 more long-live connections. And what they gain is huge reduce of orphans. This guy does not thank me, instead blame me. The thread is completely pointless.

Thanks to this thread, the mining community now knows that if your pool get's dos'd you will redirect your domain at a different pool, thus dos'ing that pool.

Hardly a pointless thread, is it?

So would you mind and tell us which other pools you connected to for "reducing their orphans"? If you post this, we can check their orphan rate - otherwise, I call this BS.

you are missing the point.

by spv mining, you're not processing tx's which exacerbates an already backed up mempool in stress test situations.  that causes all sorts of user/merchant based pain in terms of 0 confs.  you are being extremely short sighted b/c in the long run your income depends on tx growth and the resultant fees earned from them.  spv mining degrades confidence in the network of miners and discourages usage esp by new comers who suffer from long wait times.  it also encourages further perversion of Bitcoin by encouraging compensations like RBF which will destroy 0 conf tx's, which work perfectly well today.

my bet is that if you continue down this strategy path, your pool will become deprecated despite any threats or machinations on your part.

Yes, or worse...   I note that the largest pools are still offering PPS payouts.

kano hits on it well.  f2pool doesn't understand or subscribe to the original ethos of Bitcoin like many of us earlier adopters do.

they look to be in it for the short run.  make bank now and long term be damned.  i think it's pretty clear what the rest of us have to do to counter this attitude.

No contest about DoS threats.  But that point is not related to bitcoin. DoS is a violation of general *laws* that govern use of the *internet* -- so it can be objectively said to be wrong, and the victims have the right to seek appropriate legal action.

"Mining" while withholding (whatever that means) is fair game.  Once again, bitcoin cannot depend on miners being pressured to act "failrly" in any sense.  The design *assumes*  that they will do whatever is best for them; an that is what is notable about it.  The protocol does not even assume that they are holding their bitcoins, or that they care about what will happen to the price after their current equipment becomes junk.

Ditto for lying (*).  While no one likes liars, there is no law against lying per se, and -- once more -- bitcoin cannot depend on miners being honest.  Indeed, it assumes that miners will tell lies, if that helps their bottom line.

(*) What "lies" are you referring to? The fact that they put "v3" on their headers? That was not a lie.  Something else?

When F2Pool "steals" the hash of B(N) from Kano in advance of the ful B(N), it can start mining an empty block B(N+1) on top of it, right away.  The head start gives F2Pool a greater chance to solve B(N+1), which protects B(N) against orphaning.

If Kano did not let F2pool get the hash of his B(N) in advance, some other miner might succeed in sending an alternative B1(N) to F2pool before Kano sends the full B(N). Then F2Pool would mine his B(N+1) on top or B1(N), rather than B(N); and so B(N) would run an increased risk of being orphaned by B1(N).

Therfore, it is in the interest of both pools to ensure that F2pool (and all other major pools) gets the hash as quicky as possible, and starts mining an empty block on top of it, without waiting to get the full B(N). 

It is in the interest of F2pool (but not of Kano) to download the full B(N) and replace his empty B(N+1) by a full one -- but only because of the tx fees.  If F2pool fails to do that, it is actually slightly better for all the other miners, because they will have a chance to get the tx fees that F2pool failed to get.

POW blockchains are stable and behave as advertised only if a (super) majority of mining nodes follow the rules.  This technology does not and can not magically do the right thing if too many operators are dishonest and/or stupid. It is not fair game to cheat just because you can get away with it for a short while.  Bitcoin is a social experiment as much as it is a computer science project. 

Understanding the economic and social aspects of bitcoin requires skin in the game and is not something that can be done as an academic exercise.

Meh, I wake up to this crap ...


Here go read this ... in this thread ... that will tell you how it works.
https://bitcointalk.org/index.php?topic=1274066.msg13151453#msg13151453

Seriously, I know exactly how it works down to the little itty bitty lines of code how to do it ...
That's why I posted those quotes of mine, so people could get a reasonable grasp of it in terms of what it does
... and you seem to have clearly missed a very big issue by not reading my 2nd quote of myself there.

Yeah I created the thread, yeah I know what is going on AND how it works, read a little of my posts.

Clearly you still don't :P

Do you actually have any idea at all what the block change times are of pools and how they compare?
Obviously not.

As someone has already told you, and you ignored, there is one pool that does full validation block changes faster than all the empty block change pools and faster than some of the SPV empty block change pools.
(Even my pool does full verified block changes faster than the empty block change pools most of the time)

Now when we get down to these numbers, we are talking 100s of milliseconds difference in the fast pools.

Wow isn't that a great idea? Risking network forks, transaction confusion on the whole network, lost blocks, people spouting ignorance about bitcoin from the likes of ... arm chair experts like you, all for a few hundred milliseconds speed difference in a 600s block time ...

... and as I have already stated, the SPV miners also have the peer 2 peer network advantage of being in a part of the network with the majority of the network hash rate

... and produce a high % of network blocks (some over 20%) and thus for those blocks will have that obvious advantage also

I'll soon be switching my pool over to solo's very fast (faster than my current already very fast) block change time with hardware performance well above the solo pool ... that will be interesting to see the results there ...

Yeah you can quote other people over and over again, but you need to first understand it and then see what really happens in practice, not stroke your beard and theorise (incorrectly) about how you hope it might be ...

Yeah funny the maths there hey ... it's not 95% ... think about it, stop just regurgitating what someone else has told you.
Upgrades happen ... before you find a block ...
You can even determine an 'expected' upgrade time for each pool being the point in the middle of their switch from v2->v3 blocks ... or the average time they take to find a block before their first v3 block ... or ... pick another way ... but of course it will always be BEFORE their first v3 block

v4 switch coming in the next few days - fun times ahead :)
(antpool, the one holding back the v4 change, has now put out their first v4 block)

Jorge I appreciate your willingness to have a civil conversation regarding what F2pool (and other pools) have and are continuing to do.
I believe that is and will always be the first step on the road to solving any conflicts of opinion from something as earth shattering as the Middle East conflicts, specifically Israel and Palestine, or our beloved Bitcoin Ecosystem and how things should be addressed.
Being open-minded to another's opinion and not being so immature and stubborn to believe there is only one way to make something work, or being unwilling to consider the other person may have a better way to move forward.

That is one of, if not the most important consistent behavior by macbook-air (f2pool operator.)
It is not as though he has stated this is how I am going to do things at my pool and if you don't like it mine somewhere else AND those choices only impact the miners at F2pool. His statements, threats and continued choices DO impact every single miner no matter where they mine. Effectively, his actions say if you do not like it go mine another coin, or in other words, I am powerful enough to do whatever I want regardless of what anyone thinks and as I understood and agree with cypherdoc those same choices will cause an early demise for people continuing to follow that very same abstract way of handling business.

Step away from the bitcoin code and how it is designed to influence decisions by miners and consider other social implications. They say hitler always arises at some point in any debate on the internet and I am far from comparing f2pool to being run by Hitler but it is run in a dictatorship fashion (along with antpool and BTCnuggets) whose choices impact every pool and every miner.
I see Slush and many other pool owners who will do what they can to remain neutral for the simple reason they do not want to risk a penny of income. I see Kano, CK, and eleuthria much more willing to discuss what they believe in, and in my opinion pushing for an overall better Bitcoin. Eleuthria has openly stated he feels much more open to discuss these things since the closure of the Guild. Why do we think that is? Because of the backlash he may have seen from these other, much larger pools, and I think he felt a responsibility and a need to protect his miners not that Kano and CK do not feel that same pressure, but choose to handle it a bit differently.

When CK or Kano say this is the way my pool is ran and if you do not like it go mine somewhere else. Which by the way, I have only seen Kano, CK, and Eleuthria spend considerable hours and hours patiently explaining many of the same items to miners over and over regardless if they mine at their pool or not. IT is very rare any of those three have said this is the way it is if you don't like it F off.
The scenarios where it could even be construed in that manner have outcomes which do not impact the network. They are their pool, their miners.
 
I think you must agree there is a much higher standard set by the aforementioned gentlemen to educate the individual miner AND do what they think is right to empower the bitcoin network as a whole. Their attitudes and choices do not cause harm and they are always willing to have a dialog. I do not agree with Kano or CK regarding every choice they make and every rule they have in place at their respective pools but they are my number one choice for where my hashpower has been since I began mining.

Their is a social aspect of mining and bitcoin in general which is not controlled by code. Simply, it is the act of good and bad, the intentions of creating a pool structure which promotes a healthy network even when costing them in other ways.

I followed the fork earlier this year with great intensity as I try to do with everything impacting all of us. I feel I have the right to form an opinion based on what I learn, and not only how I am treated, but more importantly how my peers are treated and how the choices made by pool operators who have the ability to use all of our hashing power to make decisions. I am certainly open-minded enough to admit when I am wrong, and even if I think I am right I want to hear what the other person has to say.
I am confident you have seen the quotes from macbook-air stating they were never wrong for SPV mining, the fork happened, and their involvement meant nothing, and other than making a code change so that particular style of fork would not happen they have no intention of changing.

Setting aside the threats and other obvious character flaws they have a mindset that they will do whatever they want in concert with the other two pools not to contribute to OUR network, but control it, and dammed be anyone who even offers an opinion on their choices. To my knowledge Bitmain (Antpool) and BTCnuggets have not made public statements to that effect regardless of their actions speaking loudly. This shows they are better at handling PR and do not provide an opportunity for the people who disagree to quote their statements. In so, they are smarter at handling the situation and are not ruled by emotion. Obviously the long-term health of the network is not priority one for those two, and they are not vocally touting the fact that collectively they can cause a massive problem at any time. This is why macbook-air is seeing the brunt of the replies. The greed and control has been vocalized as priority one.

I believe you will find  this social aspect or better yet, the court of public opinion can have a significant impact on these pools in the coming months and years. The court of public opinion has destroyed the reputations of companies, and sometimes those companies are so big they can withstand that assault and with changes can maintain and even grow beyond those terrible choices.

Personally I think mining zero transaction blocks and SPV mining are just as if not more important than the block size debate but referencing that particular debate look at how those pools control the blocksize. If they do not want the blocksize to increase, it will not happen.
You must consider the ramifications of the centralization aspect, AND the fact that what isn't good for these pools regardless of why they do not consider it to be good, just the fact that if something is not considered to be beneficial to them, it is unacceptable.
The bitcoin network is already controlled by the coercion of these pools. Set aside the reasons why they have such control and ask can this be good for anyone but them? Do you see them wanting to help all of us involved in bitcoin?

We can debate the validity of SPV mining and while I still do not agree I certainly consider the points you have made.

MY biggest point is we have empowered, or better yet, given up a scenario of controlled by code to people like macbook-air who control by threats, are running in a manner exactly the way a third world country dictator would do, and have openly stated there is no intention of doing anything other than more of the same.

So while the specifics of SPV mining and consistent zero transaction blocks are debatable, there is no debate regarding their intentions or motivation of domination through the same continued practices. They do not care if the network is healthy as long as they are controlling it, continuing to make the most profits imaginable, continuing to march towards total control, and be damned anyone or anything which counters such.

while i agree with much of what you say, i don't agree with it's sentiment.

there is no way in hell Bitcoin is going to be controlled by 3 Chinese mining pools stuck behind a GFC with shitty bandwidth and a Communist gvt.  the ROW has much more going for it and it's just a matter of time before the economic majority of Bitcoin holders will exert their influence to change this situation.  there is no room for bad attitudes and authoritarianism in what has now become a public good, ie, a new monetary system for the ppl.  bullshit like spv mining and 0 blocks won't be tolerated in the long run as they don't serve the system well.  

it's just a matter of time.

At the very least, the system itself will sort out the zero transaction block pools as the block halving will decrease the reward from mined blocks substantially and make transaction fee mining far more important as a proportion of profit than it currently is - unless of course the consortium decide to drop transaction fees even further than they currently are (which I doubt will happen). Current block rewards are often up to 2% transaction fees and once the block halving occurs that will be up to 5%. That is a massive drop in potential profits for miners... but then miners don't necessarily have a good history of making the best choices, often choosing alleged 0% fee pools and those mining bullshit coins in the fake belief it's giving them more profit even though those same pools often underperform far more losing more profit than anything gained through what sounds profitable. OOC usually does a nice analysis of profitability proving this, yet miners go on mining in the wrong places...

Well Satoshi did say that in his design paper ... fees would take over from block reward ... but I guess there's a lot of people who have no idea about the design of bitcoin and the path that the design expected to take :P

The real issue is that so many people have their own agenda of what they want bitcoin to do.
Fortunately most of them have been unable to push those agendas ... fortunately since they all seem to be based on lining their pockets first and the advancement of bitcoin second (if at all)

Now a few relevant points from Satoshi's document for those who may not have ever read it :)



... and of course the last 2 sentences:

The SPV mining pools clearly fail badly on that last important point.
They care not whether they work on valid or invalid blocks.
Yes that is their fault, not any one else's.

Forgive me if i'm wrong; but Antpool appears to be doing the same thing (found block, not submitting straight away,  mining on header of found block, submitting both in quick succession).. standard behaviour from them?

Blocks 387005 and 387006..

Yup, it's standard behavior for pools that SPV mine I'm afraid, not just f2pool  >:(

We cannot assume action will be taken in the face of a rising dictatorship.
We must inform.
We must go on the offensive.
We must lead, work with, and follow great community leaders with the agenda of making bitcoin what it should be.
We cannot sit back and allow miners to be uneducated regarding the issues which are well past at hand.
These are problems today where those "elite" should have previously stepped in.

Are we going to wait for our governments to save us from financial destruction as well?
I have not been. I work everyday for my own personal independence with more than a fair amount of time of that involving cryptocurrency and 99% of my crypto involvement is pure bitcoin.

Do not wait for our beloved Bbitcoin to be saved by an "elite" who are only poised to lose some control, save it yourself by whatever means possible.

Are you serious?! Any IP address is PUBLIC and nobody need to have any permit to post this info anywhere.

Yes, this has been going on for far too long.

You have to ask yourself why it is hidden so well. It actually is not hidden at all, it is hidden in plain sight.

Our "coders" (and I say our because if you have a single satoshi then you have a stake), our "coders" of bitcoin core are scared of those pools. If they rock the boat they may have to deal with something sooner rather than much later. Look at the blocksize debate. Regardless of which side of the isle you are on it was a fixed match from the beginning with ALL of the core "coders" including Hearn and Gavin looking to what the 60% controlled by China's "elite" pools had to say.

I haven't been concerned about a 51% attack. That is too degenerative to our economy and would hurt "them". "Them" meaning the pools coordinating the control of bitcoin. They want far more than such. They want to tell us what the price will be, what coins we mine, when we mine them, and what percentage we receive. They want and are dictating the core code in front of our faces.

Bitcoin is mine, yours, and each person's individually. No different than a revolution in a country except this is the world financial revolution which has the opportunity to change the world's future for the better. We do not need this war on two fronts with internal fighting. Miners should unite by dissolving their presence into pools which adhere to appropriate mining protocols and pools who practice the ethics of what is good about bitcoin. Get away from the greed of centralization.

Surely anyone can see that those pools having the amount of hash they posses today cannot be good for the infrastructure.
If others see such and receive education from their peers many will care, and will act. Many will also ride greed and ignorance, but it is not something to take lightly.

At the rate they are growing we will see the China pool cartel dictate what bitcoin becomes through the decisions of a handful of people.
They already refuse to do things such as distribute the source of cgminer when they make changes which completely goes against the license to use it by the creator(s). How can anyone think that is anything but a conscious decision to give everyone the middle finger at any opportunity to continue protecting themselves?

macbook-air has openly stated and it is quoted here on the forum that there is no room for conversation regarding SPV mining. They will continue to do so regardless of what anyone thinks, regardless of the hard forks it has been PROVEN to cause.
This was literally stated by MANY community members AND if anyone cares to recall it was in giant red letters on the bitcoin.org front page which is when people were told they could not trust the normal amount of confirmations.

No, we cannot support them, it is that you must block them. The only way they will listen is if money leaves their pocket in a significant fashion.

This is not quite correct. They are submitting it straight away as they have a lot to lose by not submitting it. It's just that they start mining on the header of a any pool's found block without verifying it's valid. As they're only mining on the header they are also unable to generate work with further transactions in it so they are always empty transaction blocks they're mining. In their next work update from the pool they are then working on verified blocks with transactions mined in. The effect you are seeing is that SPV mined blocks by design only ever occur within a short timespace of a previously solved block. The fact that it's often two blocks back to back by the same pool is purely because those pools are TOO FUCKING BIG and get lots of blocks.

 

You do realize they can be forced to lose quite a bit of coins every day by pointing a modified cg miner that simply discards any solution over the current diff.

If I point my 30th at them with a modified cgminer that tosses all diff over 72 bill now soon to be 79 bill  they will pay my hash about .2btc a day  and my machines will not ever earn a block.

So if :

30th cost them     0.2 btc a day
300th would be    2.0 btc a day
3000th would be 20.0 btc a day -------------this would be enough to harm their bottom line.


and the attackers  would never get hurt.

So my question is why isn't any one doing this to them?

Next question is if this is being done to them are they doing their tactics to survive?

Last question is  I can see no way they can defend against a block discard attack so why do they take the risk of their type of pool?

http://youtu.be/ivgxcEOyWNs?t=149m

Scaling Bitcoin presentation about GFWC and block propagation.

The pools have good hardware and block propagation is indeed fast with the help of the centralised relay network and well coded full validation.

His interest is p2pool, so yeah that's a lot of everyday crappy servers.
However, p2pool solves the problem itself anyway due to effectively having it's own fast propagation network
(though the way he and others centralise p2pool reduces that advantage)

I hope the OP realizes that it would be trivial for any SPV miner to simply direct a small amount of hashpower to your pool and listen for block changes the exact same way they were previously doing as described in the OP. It would also be trivial to use different addresses to mine on (have the payout sent to).

The only thing that the OP is doing is leaking private information that you have no business making public. If you are going to leak the IP address and payout address of someone you suspect to be SPV mining, then why should I (or anyone for that matter) trust that you will not leak my IP address and payout address if you think I am doing something that you do not like? If you are willing to leak this private information, then I do not see any reason why I should even trust you to payout my mining revenue when mining on your pool.

If you think that SPV mining is "bad' then I would suggest that you not engage in this practice. If you feel strongly about SPV mining then you can warn others about this practice and why it will result in them loosing so much mining revenue. It is not however any of your business as to what business practices that others engage in when you are not a party to a transaction.

If you seriously think that shaming a "evil" entity because they are doing something "bad" for Bitcoin is going to produce any results then you are naive. If someone wishes to harm Bitcoin and the Bitcoin network, and has the resources to do so, then they are not going to care that someone is shaming them.

If you think that SPV mining is as evil as you claim, then I would suggest proposing a BIP that prevents this practice. If SPV mining is as dangerous as you claim, then surely the entire network will quickly adopt a BIP that prevents SPV mining

I didn't ask you to trust me :)
Please don't go near mining at my pool :)
P.S. read the thread title ... moron :)

... and for those less scrupulous than me, they might even consider sending bad/corrupt headers to the spv 'dead pool miners' since they aren't providing any mining results, that's not gonna affect their "shares" ... and see what havoc you can cause to their spv mining process :)
They may just have to resort to doing fully verified mining like everyone else :D

forgive me for asking that:
what stand S P V for?
The Subject is clear but not the words.

I.e. S Single P Pool V Verification ?

The term comes from SPV wallets, Simplified Payment Verification
https://en.bitcoin.it/wiki/Thin_Client_Security#Simplified_Payment_Verification_.28SPV.29_Clients

Thank you Kano, as a non english native, it is hard to find out the meaning behind those shorts.

Heh, someone pointed out a link to reddit where stolfi was still trying to blame the devs for the July fork there also and claim that SPV is OK.

Someone there even explained the point about the fact that only 1 miner with 0.001% of the network could have caused that fork any time after the 95% consensus was reached, even weeks after.
Doesn't matter adding 2 weeks delay.

When it happened, and for any period after that while the active SPV code at those big pools was unchanged, it only takes one single V2 block for SPV mining to create a > 50% fork of bitcoin.

I wonder how he explains that SPV mining isn't bad for bitcoin ... when a single block from a single tiny miner can > 50% fork the blockchain ...
Edit: and in case it wasn't obvious, that situation exists still today while those pools continue to SPV mine.

Clearly he has an agenda.
I'd suggest anyone reading what he says to check other more respected posts before taking any notice of what he says.

 >:( Just looked that KNC also does SPV Mining.

Is it just me who think it is like "steeling" the work of other Pools.
(I know it is not real steeling, but it feels like it)
It is not a verry social behavior.
 

They've generated empty transaction blocks. While SPV mined blocks always have empty transaction blocks, empty transaction blocks aren't always SPV mined. Either way it's a bad practice in its own way, but it doesn't necessarily mean they're SPV mining.

in this case, where they know the previous block is valid b/c they mined it, why wouldn't they simply mine the next with tx's in it?  the reason these spv miners do what they do is b/c they don't want to waste time validating another pools just received block, which is not the case in this situation since it's their own.

what good would this do?  from what i hear they validate that the headers hash to the correct target to be a valid solution, no?

It is both as can be seen when 2 blocks back to back come from an SPV pool and the 2nd block has zero txns. The reason is they've not gone to the effort to make the bitcoind validation process fast in their own nodes and they don't want to wait for bitcoind to validate the block (it takes time) before starting on their next block. For solo.ckpool.org and kano.is we run a customised bitcoind which speeds up the validation process dramatically, making this delay negligible.

They wouldn't be able to use the header ...
They'd have to get it from somewhere else, which no doubt they do have a web of 'dead pool miners' connecting to pools all over the planet ... ... ...
but it would be one less source for them.

Also note the obvious that you are assuming they aren't being stupid in their testing of the header.

They did clearly show they were morons before when they weren't even checking the block header version number ... even a day after knowing all blocks should be v3 and to ignore v2, they still mined on a v2 fork for the 2nd time ...

do headers obtained from stratum include a block version #?

i was told that they at least check that the header contains the correct solution.  thus, simply sending them a random malicious header that doesn't have any POW behind it shouldn't work.

but again, in the Antpool example given of 2 of their own blocks found sequentially with the 2nd being an spv 0-1tx block, they already know the 1st block is valid.  afterall, they produced it.  why bother then with spv mining the 2nd block instead of just stuffing the 2nd block straightaway with tx's so as to capture fees too?

also, the root emphasis as to why they spv mine is to avoid constructing the getblocktemplate during stress conditions of full or nearly full blocks and bloated mempools:

https://www.youtube.com/watch?feature=player_detailpage&v=H-ErmmDQRFs#t=4330

and here:

https://bitco.in/forum/threads/gold-collapsing-bitcoin-up.16/page-155#post-5252

Logically, stratum has to be able to construct a block header after modifying the sig in the coinbase transaction, so the miner must be able to generate a full block header to hash.

But the answer is yes.

They obviously didn't check all of the header: they didn't do a simple single: does v = v3? check even a day after the v2/v3 fork.

How much of it do they check? Who knows. But they didn't check one of the simplest checks.

It can still be taken back to the basics of good versus evil as well.

If every pool did what those pools are doing the network would be a wasteland.

They are 60% of the network and some people are asking to continue the debate the finer logic of the acts themselves. Do not get me wrong, I can appreciate a good debate on the topic, but when you strike the core cypherdoc ask yourself that same simple question:

If every pool mined zero transaction blocks along with SPV mining how long would bitcoin last?

That is a threat and a lie

... again that is a threat and a lie

here's an interesting convo i had with Lightsword on this a week ago.  note the IRC chat with Wang Chun (btw, is he macbook-air?):

apparently all the Chinese miners had upgraded to v3 except for one single full node in Antminer's pool of nodes.  when BTCNugget released their v2 block (they were one of the 5% of miners who hadn't done the upgrade), this one non-upgraded node relayed it to f2pool via their stratum listening dead miner.  then f2pool proceeded to mine 4 spv blocks on top of it along with 1 by Antpool.

https://www.reddit.com/r/Bitcoin/comments/3uugeu/bip65_is_66_on_the_way_to_first_activation/cxkqv0l?context=3

no, i get it. i don't think it's right either.  but we need to understand why they're doing this from a technical level.

imo, bigger blocks would solve the problem by emptying out the mempools of mining full nodes and decentralizing mining outside of China.  yes, spv mining by the Chinese might get temporarily worse in the short term as they struggle to maintain their hashing chokehold on Bitcoin but eventually the ROW (rest of world) will catch up, in terms of mining share.  on the positive side, the Chinese miner BTC holdings should skyrocket and there are many positive things they could do to compensate.

seems our little buddy luke-jr isnt such a good christian..

block 388365 - f2pool (and to be fair f2pool actually processed tx for a change)
block 388366 - eligius (1 tx - 25btc)

have at it guys; red-handed..

Eligius doesn't SPV mine... yes, they produce empty blocks on that pool, but it is a byproduct of the way the pool distributes work.

The solution is quite simple
Everybody has own good reason to mine in CHINESE pools.
So just fuck them and stop mining there. If you do believe they are destroying Bitcoin there is no such Good reason to justify YOUR OWN will to mine there.
But unfortunately it is not the case...
....
Ps: if any one speaks CHINESE please translate it ;D

Well, yes you could word it that way.

or in detail:

What eligius does is they send out empty block work every block change.
Then soon after, they send out block work with transactions.
During this gap, empty blocks can of course be generated.
The length of the gap can be determined by seeing how often, over a long period of time, they produce empty blocks.

Their excuse is that it is faster than sending out block work with transactions the first time.
Of course it is faster, but faster than what else?
eligius is SLOWER than my pool https://kano.is that always sends out block work with transactions.

They are blaming bitcoin for their poor pool software performance and thus producing empty blocks to compensate for their skill level.
The problem is their pool software performance.
Rather than resolve that, they instead blame bitcoin and produce empty blocks.

I'm curious how many people and hash power outside of China mine in Chinese pools.  Even more curious as to the reasons why they do this.  (If a majority of mining were in Antarctica I would be asking a different question.)

A surprising amount. I've even seen quite a few respected members on bitcointalk say they're mining on f2pool/antpool. Pretty sad when you've got great alternatives like this pool.

I will add that it is pretty said that so called "respected members on bitcointalk" do use Chinese pools....

Well, the discussion goes to SPV Mining.
F2Pool is improving, as I can see it, so it is fair to say the message come through and they try their best.
AntPool still produce 0 Blocks. They do nothing, just counting their income.

Well F2Pool block changes have sped up again since the v4 change completed ...

Sure and the discussion goes how to slow it down remember?

At the end Chinese brothers will do whatever they want and how they want it. It is their style of doing business in general. That is a statment  from my expirience with them in all fields unrelated to BTC.
1. Stop to mine there immediately!!!
2. Stop to mine there immediately!!!
3. For fighters who want to stop them even loosing some money.
 a:) Rent and point Petahashes to their PPS pools(via patched proxy ;)) and do block withold. Be constant and they will feel the pain ;D ;D ;D ;D

>Sure and the discussion goes how to slow it down remember?

Yes, so far so good

>At the end Chinese brothers will do whatever they want and how they want it. It is their style of doing
>business in general. That is a statment  from my expirience with them in all fields unrelated to BTC.

Well, that is a more off topic thing (even if i agree with it)
But is it their fault when people want everything cheaper and cheaper and buy chinese product only because
of price? Go in your home and shout: Out with everything from china, i guess your home is nearly empty and
in some cases even the house will collaps!
This is a discussion with only one conclusion: If you want to change something, you have to start first at your own!

End of ot



 

I have started long time ago on my own if it matters. The point is that to change something as a whole in btc all of us shall act as ONE and SPV is no exception.

Peace...
And because I know MacBook Air greatest fear is block withold once again block withold attack against any ppps pool in our case CHINESE will kill it for sure ;D

 ;) I don't mine there as well.

Maybe your speed ups could go into the official client?

ty Kano.

one day this will all be sorted out.  the good news is you've put in the hard effort to make it so.  which will give you an advantage when the dependence on fees escalates.  like maybe around July.

Let's not confuse empty blocks with SPV mining.  F2Pool has definitely taken steps to reduce the number of empty blocks they produce.  Since macbook-air made his post:

KnC - 2 of 35 are empty
bw.com - 2 of 34 empty
AntPool - 13 of 81 empty
Eligius - 1 of 10
f2pool - 2 of 110

That's a far lower percentage than is typical for them, so whatever changes they made have produced noticeable results.

Having written this, the fact remains that f2pool, AntPool, etc continue to SPV mine.

Yes they all do and the forking issue remains with f2pool.

But all the others have both the forking issue and the empty block issue.

If we could get all spv miners to do what f2pool did about empty blocks. The forking issue would remain
But maybe they can figure a way to stop the forking issue. Which could be far greater problem then the empty block issue.
Is there another problem besides forks and empty blocks?

if you read my post above about what appears to be the granularity of how the bip66 fork actually happened, if Lightsword is correct, then upgrading that one Antpool node from v2 to v3 should've solved the forking problem:

https://bitcointalk.org/index.php?topic=1274066.msg13205888#msg13205888

And that is precisely why SPV mining is bad.  One bad actor - in this case a single node - relayed a block that never should have been included in the first place, and wouldn't have been if it was properly validated.  Then it got compounded because the other pool saw the block, also didn't bother validating it, then built a block on top of it.

precisely.

i wasn't condoning it.  i am just trying to explain it.  which is why delving into the technicals is so important so that hopefully we can understand how to counteract these subversive activities.

fantastic. just out of curiosity did you submit your bitcoind changes upstream? I would be interested in knowing which kind of changes you applied so I wonder if there's a PR somewhere on Bitcoin core github repo.

in any case keep up the good work!

This "problem" was definitely a problem for some miners who lost block rewards.  How much of a problem was it for users of bitcoin?   If it was a large problem for a few miners and a tiny problem for the rest of bitcoin, could this perhaps been a demonstration of the Bitcoin incentive structure working?

If someone believes this analysis is incorrect, I'd like to see a cogent explanation of who was hurt and/or how people could have been hurt.

Payment systems that rely on transaction confirmation suddenly are in a position where they no longer know if their confirmed transactions are confirmed at all.

Transaction confirmation tends to be rather important ...

If >50% of the network is mining on an "invalid fork" then is that fork "invalid"?

we need bigger blocks to clear out those mempools

It is up to each user what is invalid and what is valid. That is distributed consensus.

If a BIP101 chain is the longest, Maxwell is free to consider it invalid and continue working on the 1MB chain (as he as said he would). To Maxwell a 1MB chain used by 10 people would be the valid chain. To many others the longer chain used by many would be the valid chain.

Eventually the two sides would not be able to transact with each other, this is fine.

We are all free to choose which chains we consider valid or not valid.

I think the chain that follows Satoshi's vision and white paper as a global payment system everyone can interact with directly is the valid chain, and will follow that even if it is shorter and used by fewer people for a time. That is my choice and option, no 3 core devs can tell me otherwise or force me to accept chains that are a fork from Satoshi's clearly stated vision.

Correct, but the issue is that people who make decisions based on confirmations can no longer be 100% sure if the confirmations are valid.

If bitcoin has no stability of confirmation of transactions it's value is greatly in question.

An earlier big fork a few years back, some bitcoin dev had the not so bright idea that going against the 'valid' fork was the solution.
The biggest pools agreed and thus any transactions that were in the valid fork were no longer guaranteed to have been confirmed.
Yeah that's directly against what you've said.

You can look at Bitcoin as an altcoin where they are all scams and who knows what altcoin is going to appear tomorrow and which one will no longer exist or have any exchange value the next day.
However, Bitcoin is no longer is in that arena and hasn't been for many years.
So simply saying that "yeah it's whoever feels like doing whatever they want" wont work any more.

A $4billion currency requires consensus among those who control more than 50% of it ... ... ...
The actual problem of course is that more than 50% control exists already and that continuing will indeed be the downfall of bitcoin.
I'm sure someone could go make a news breaking article about this current problem in Bitcoin and make the news headlines and we'd see the price of bitcoin fall drastically ...

P.S. A BIP101 chain will never be longest. It rarely ever even gets a block attributed to it.

why are you saying this?

They just think that they'll be able to get more profit at that pools (especially using PPS reward scheme) than at other pools.

Maybe some of these people are mounting a deliberate block witholding attack on these large PPS pools.

Well Prop by design is flawed - so people don't use it any more.
PPS by design is flawed - but pools still use it ... ... ...

It is never certain whether a bitcoin transaction is confirmed or not.  There is always a risk that a transaction can become unconfirmed in a reorganization.  It is up to payment systems to deal with this intrinsic behavior of bitcoin.  The presence of occasional SPV mining might increase the number of blockchain reorganizations, making it desirable to use a more conservative number of confirmations before releasing goods.  But SPV mining also reduces the orphan rate, so the reduced orphan rate lowers the risks associated with small numbers of confirmations.  Note that payment processors can always run a full node and make sure that any blocks in the chain up to their payouts are valid.  If they don't run a full node, then they have to trust any full nodes that their client uses.

If there is a significant risk, IMO it comes where a payment system uses an SPV client to access a "full" node that isn't validating the entire chain.  I'm not sure this extra risk is particularly bad, because it increases the incentives for people to run a full node.

Another way to look at this is that the miners are primarily performing an ordering and publishing process.  Miner validation doesn't really provide that much security when there are hundreds of times more full nodes that validate blocks for their users than nodes that mine a majority of the hash power.  (However, mining validation does serve a spam prevention purpose, otherwise double spends would pollute the block chain with useless data for transactions that will be rejected by every honest full node.)

The case of differences of opinion as to block validity is a separate issue from SPV mining.  It ultimately comes down to what is, or is not, "bitcoin" and how disputes between Alice and Bob get settled when Alice she claims she paid Bob and Bob rejected the payment because their definitions for "bitcoin" differed.

I wonder what people think about block withholding attacks,  particularly the advisability, morality and/or legality thereof.

The actual issue is the rules of Bitcoin.
The basic issue is that not everyone everywhere follows the rules that define Bitcoin.

It doesn't really matter what opinions exist about what is and isn't Bitcoin, the issue is simply the rules that define Bitcoin.

I can go make some altcoin scam and have rules that allow double spends and let people steal coins etc ... but that, of course, isn't Bitcoin.

The Bitcoin rules are defined as to what the block header looks like BUT also includes the rules that define the validity of transactions that the block can confirm.
It isn't just the first, it is BOTH

So when a pool is ignoring the second set of rules, by building on block headers that aren't guaranteed to be valid Bitcoin block headers, they are not Bitcoin.
Yes they may produce valid Bitcoin blocks most of the time, but no they are not guaranteed to produce valid Bitcoin blocks all the time, because they are ignoring some of the rules that define what Bitcoin is.

I guess one solution to this would be to fork off the SPV miners into some SPVCoin altcoin and be done with them.

However this is also problematic in adding NEW rules to Bitcoin to ignore data from those who are breaking the Bitcoin rules.

Basically, they need to own up to the fact that they are NOT following the Bitcoin rules and either piss off and make their own SPVScamCoin or fix their mining and ensure it follows the Bitcoin rules.

They seem to want the value of Bitcoin rules applied to their non-Bitcoin rule mining.

In my opinion that's a scam and no one who wants to be a part of Bitcoin should be instead supporting altcoin pools that pretend to be a part of it.

hey, you guys should take down your BIP100 block flag support that you're broadcasting on the blockexplorers. @jgarzik has scrapped it: https://twitter.com/cypherdoc2/status/677184373699969024

Probably the best solution I've heard so far. See how quick they change their ways once they realize they will be kicked of the main chain..... :)

Though I have no idea what BIP100 has to do with SPV mining ...

Weird I though it was called Bitcoin, not GarzikCoin ................

Kano, that was a great way way to put it. They are not following the rules of bitcoin when they do not properly validate.

I agree with everyone who commented about people mining at any pool which uses SPV mining, but I also see the Bitcoin publicity crew kissing their ass, like the bitcoin meetup in HK. It sets a very bad example for miners, especially new ones. I wonder how many miners even think of another pool when they receive their miner and set it for antpool. They see another large pool and try f2pool. It takes a while for many new people who would care about SPV, zero transactions, etc to find a pool they agree with.

It goes to show how bad choices for the entire arena are made in plain sight and most do not care, but some do, and many others are beginning to pay attention.

I hear the people mentioning the block withholding attacks, but I feel like that would put me on the F2pool and antpool level and I am not a scummy POS no matter what one particular forum member who is involved with macbook-air tells people I am, heh.

I am also not saying someone else is a "bad" person for performing a block withholding attack. Everyone must decide what their actions are going to be.

To me, it is extremely unique we need to have a conversation regarding the technical specifics of why they choose to continue ignoring the proper way to validate. I understand they want to gain an advantage, but when they are already doing scummy things like dead-pool mining without permission, SPV, zero transaction, doesn't that pretty much size it up for anyone with common sense?
Maybe it is the pure enjoyment of discussing technical aspects. Or, an attempt to define a combative method.

If things were handled correctly the core devs would realize it is important and have already put something in code.
They don't care, they are too busy with their block size debate and I haven't heard any progress on that front, at all. I know there were several proposals, and a whole bunch of talk with XT, BIP 10x, etc but what about a vocalized decision? "Hey, we aren't doing jack about blocksize because we are working on this right now." Grow a set and step up. I became bored reading the mailing list.
As Gavin loves to mention, it is indeed a bunch of "bike-shedding". Don't get me wrong, I am not saying Gavin and Hearn had it right either. At least they made a valid attempt.
Why aren't CK and Kano core Devs? It isn't like there aren't a couple of real losers in that stack who should be replaced. Starting with Luke-JR.
By the way cypherdoc thanks for pointing that irc convo with him out, it is usually the biggest preachers who are also the biggest hypocrites. The whole "Preacher's Daughter is a wild woman" thing is not a stereotype because it isn't true. Personal experience stands strong on that point. Good or bad I loved going to church as a teenager for that reason more than faith.

I have been sending some messages with few responses to people who I think can have the most impact on the problem, without involving the real media. Sometimes it can take a while for people to respond, it has happened before and worked out well. We do not need the bad press which would surely come from involving big media. The story is too big. The media will love writing about the potential Bitcoin Blowup of China versus the rest of the world, and that hurts everyone. I think a big help can be the equivalent of writing or calling your senator here in the US. It takes a mountain of people doing it, or someone with dirt on the right person, but it can help a situation. I've seen it with Veteran Affairs and my father, but it only helped for about a year and the problems came back.

I hate the idea of giving up liberty for protection, and I feel the same way about Bitcoin. I don't want a "big brother" governing every aspect just to make sure a dozen people stop being so freakin greedy they ruin everything for everyone.
At some point though something has to give. The rate of growth of just Antpool and F2pool is monstrous compared to every other pool because of the momentum. Unless someone does some heavy advertising about it, the concept simply does not reach enough people who care in our "little" bitcoin world. Even the youtube videos of bitcoin meetups never mention any names, it is just the facts mam, even if you get to hear those. Most average miners do not understand it. Which is why I push for simple talk but enjoy the technical.

What is enough for the "big" individual miners?
When they see it impact their pocket.

Maybe one of the spreadsheet math geniuses here could put some numbers together showing what happens when 95% of the network is  SPV mining and a fork happens which isn't caught for 24 hours, or what if that fork happened and they decided to stay on that fork?
Bitcoin would drop like a rock.
Or something showing projections on the growth over the next two years if nothing changed in the core code and growth continues at the current trends. Even factor in a media frenzy about the issues we are discussing.
Surely people who recently invested 100k in S7s would want to do something to have an impact if it was presented by someone viewed as more neutral, maybe a non-miner, non pool operator, just someone holding coin since 2011 who doesn't want to see their investment end up in shambles.

Of course, I mentioned this before. I believe the people holding hundreds of thousands of dollars worth of bitcoin or more have already setup escape plans. Besides the fact that even if they lost it all today they still are far from ever being negative. They are already sitting pretty well.
However we do have some people and companies with recent incursions, investments and shareholders who would want answers, ala overstock, the twins, but that is too close to mainstream media, which invites oversight. Governments could even collude to control bitcoin to "help" the system, and that is something we do not need regardless of it being possible. The effort alone is bad publicity.

No, I think we need to start with the people who represent bitcoin at the meetups, the conferences, and especially the ones in Asia.
It is so odd that they openly debate the impact of the great firewall and the people behind it talk about what a disadvantage it causes yet they own the network. To me, again, common sense, and the statement is laughable. There are so many ways they are currently getting around the GFW without including SPV and ZERO Transaction blocks. Maybe this is an area I do not understand but the numbers speak loudly to me.

My main reason for this post is too encourage others to use the brilliant minds I have been witness too so many times here on this forum. I've seen so many creative people here, and I know the common sense, ability to create unbelievable software, the creativity which goes in miner modifications, and simply the thoughts of so many people about any random topic far outweigh those same things I see from people on a daily basis. IT isn't that I am not around some brilliant people, but they do not have the same intellectual need for an outlet of those attributes. Not to mention this is bitcoin, and we love it for it, and what it has already shown is possible. The number of doors one can enter are endless.

I told someone the other day in a PM that they are wasting their abilities. Oh, he has his hands full. He is a fairly large miner, he writes his own custom software, he works a day job, and sleeps a few hours like me. He also does charity work, has a wife and kids, builds other projects all the time, and on, and on, but his skills are so varied he could be doing so much more to actually help Bitcoin take a next step and it be profitable for him. I have no reason to think there is much he couldn't do, but he is not interested in other projects outside of his safe bubble.

I understand that. I spent about twenty years living where I am still spending 10, 12 - 18 or more hours a day, but I did start going outside that environment through my work and doing other things in the community which made some friends and some enemies. I enjoy knowing a small group of people can have a huge positive impact on many without spending a dime.

One last thing I will touch on is people should support the people doing good things whenever possible and you do not have to do it openly you can be covert. If you aren't well off and you are struggling just to make ends meet use that creative genius to do something different. Put a project on hold and make something. You don't have to spend a thousand or even a hundred bucks to show appreciation.  Make something with a soldering iron out of scrap wire and wood. Design a circuit which does something interesting even if it is a play on something else. Research someone and code something you can use to pay someone a compliment.
I have a very small group of guys who have been through some crazy things together where we send each other something out of the blue we know that person would appreciate. Be it a local item they cannot get where they are, a pocketknife, a sign, a pin up picture, Venison, or something they have never tried before, etc. It not only encourages that person more, it damn sure is one hell of a thank you and unbelievably motivating. I am not saying to expect anything, simply to give something. Don't buy someone a gift card for Christmas unless you know that will thrill them, or get the gift card and a little something you had creative input with. That whole pay it forward thing is an amazing concept and has sure made some days that were going very bad given the perspective that those bad things didn't even matter. Yes I practice what I preach, and I am going to keep doing what I can to change SPV mining and mining zero transactions with the strengths I have while honing my weaknesses until they are strengths.

You don't have to spend a bunch of money, but you do have to spend some time.
That goes for selectively paying it forward, and changing the Bitcoin issues we face.

I am very interested in being part of a group of people who are serious about causing a change in bitcoin. No judgement, No Dictator, a common goal of causing a change to SPV mining and zero transactions, using creativity and other means as necessary. I am very open-minded to other goals as well, but I feel these are two extremely high priorities.

Have a great day, evening, morning, or wherever you are, I hope it goes well.  

thought you might be flagging 100 support in your blocks.  i know ck is.  that won't be necessary now.

I want BIP100 - I'll be leaving it there.

why?  when one pool of 20% or more, like f2pool, can veto any block size consensus?

The important issues are:  What are the rules of bitcoin?  How are they defined?  How can they change?  Who can change them? How can the relative merits and demerits be weighed when different stake holders have different interests?   How can nodes breaking these rule be caught, coaxed, or coerced into changing their behavior?  These issues are much more important than any particular technical discussions, because without context all of the technical debates have no context and little value.  Defining the problem is much more important than defining the solution.

NEW rules would be problematic.

The current rules are clear.
Bitcoin's value is in those rules.
Someone breaking those rules is not mining bitcoin.

We know they are breaking the rules, but it's rare that they are punished for doing that.
It only happens when their 'rule breaking' results in an invalid block.

What I am already suggesting people do is 'coax' them into not breaking the rules.

Who are the pools who keep doing this and empty blocking?

If a pool mines empty block it does not mean that pool is SPV mining for sure ;)
But some pool ops have clearly stated something like: yes we are innovative and because of that we are and will continue with SPV minig. Which probably means something like we are big you are small so go and fuck yourselves
And all those pools have tx and non emty blocks also + support from the community. how pathetic...it is about time all of you who mine there for whatever reason to stop doing so if you truly understand and believe that SPV is bad
No ifs and no excuses just fuckem

http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-December/012103.html

Just another name for what they need for side chains.
Sneaky aren't they :P

Now Tx fees are about 1% of total block reward (25Btc+Tx fees). When block halving occurs, they will be about 2%. Doesn't this discourage mining empty B(N+1) and switch to full B(N) immediately when it is available.

Hm, I just came back to this old thread to find that some people still don't get it.  (And some of them resort to insults, on top of that.)


Sorry, that is exactly what I can't agree with.  It seems that miners have come to constitute a connected social group, much as ranchers in a county or plumbers in a city, and believe that they must have a code of ethics and have common policies and decision --- such as ostracizing peers that don't follow those rules.

But that is bad, terribly bad.  Bitcoin's "Fundamental Assumption" is that mining is distributed among thousands of independent miners that act individually, motivated by their individual gain.  That is, selfish and greedy, not "good" or "honest" in any sense.  If miners start acting as a group, sacrificing some selfish gain in pursuit of group profits (or other goals), then it is impossible to give any guarantees at all, not even probabilistic ones.

Today the "good miners guild" may decide that its members should not do hash-stealing and should not mine empty blocks while waiting for the parent to download -- because they decided that such things are bad for bitcoin. (I don't think so, but let's skip that issue for now.)  

But tomorrow they may decide that the minimum fee should be raised to well above the cost, because of suitable excuses --- and all guild members agree to orphan any blocks that contain low-paying transactions.  Or the guild may decide that transactions from or to a certain wallet should not be processed, because that wallet belongs to the "wrong" side in some war, and the guild does not want trouble with the government that is backing the "right" side. Or the guild may decide to increase the block reward via a soft  fork (https://www.reddit.com/r/btc/comments/43w4rx/how_core_can_increase_the_21_million_btc_issuance/czlsk2q).  Or...

These last things are typical of what the "bankers guilds" -- formal or informal, national and international -- do all the time; and are percisely the sort of thing that the bitcoin protocol was hoped to avoid: miners colluding to act so as to achieve a commong goal, rather than their individual selfish interests.

That is the the only original feature of bitcoin, that justifies its existence: it is a system of incentives that is supposed to achieve the desired group behavior out of the selfish choices of anonymous, uncoordinated, unregulated and unscrupulous miners.  

And it almost worked!  It fialed, not because of trifles like hash-stealing, but because mining, quite unexpectedly, became concentrated in a handful of big pools and a few dozen big farms.  (In a rarely-quoted post, Satoshi estimated that the number of independent miners would grow to "100'000, maybe less", serving "millions" of clients.) Not only the big miners, but even miners in the 5% range, like Slush and KnC, are already too big to make the Fundamental Assumption believable.

Indeed, objectively, the present concentration of mining means that bitcoin is already dead.  It still works as a payment system, but it requires trusting some third parties -- the 5 big miners.  Than, what is the point?  

(What is worse, the concentration happened because of many unavoidable social and economic factors; the advantage of short propagation delay is only one of the weakest.  I see no hope of this problem being fixed -- unless the price crashes to pennies ber BTC, n which case industrial mining woudl not be worthwhile, whatever the difficulty.)  


Big pools and miners identify themselves for marketing reasons, but they don't have to.  In the original design, in fact, it was sort of assumed that  miners would be anonymous, coming and going at random times with no control or coordination.  A miner with 75% of the hashpower, who did not care fro marketing, could easily disguise himself as hundreds of anonymous miners with less than 1% each, with unknown geographic location.

Thus, boycotts and public campaign against transgressors of the "guild ethics", besides wrong in principle, are ineffective.  The attacked company can split and mutate into other pools, and no one will know whether they are independent or owned by the same persons (and maybe located under the same roof).

My advice is that miners forget about "the good of bitcoin", as doing so will only bring them frustration and stress; and just behave as Satoshi expected them to behave.

Oh you just woke up after falling asleep in your chair for a few weeks and decided to post some random tripe?

Firstly, hmm I wonder why F2Pool has way fewer empty blocks lately?

Secondly, yeah I know time moves on and you forget what was posted before ...
I'll repeat the comment: Read the topic title!
Most of your post clearly missed what the topic title says.

... and lastly something that happened in the meantime ...

Antpool's empty block count capacity was in the order of the size of the mempool build up recently that was delaying transactions.
So, if you ever have a complaint about slow transactions, I can tell you where to go :) ... talk to Bitmain :)
Block capacity is still big enough to cover transactions, except that certain pools are still sending out lots of empty blocks that ignore the transactions that are waiting to be confirmed.
My pool's average txn fees gained over the last 11 weeks, 250 blocks, is 101.2% i.e. 1.2% extra due to transactions.
After the halving that would be 2.4% ... yeah takes a little primary grade maths to work out what that means ... though that's probably above the level of an arm chair economist with a point and click web degree :P

Meanwhile, Bitcoin is continuing on as usual. It's still working.
Yes I know you want Bitcoin to fail, but no it wont.

I don't think you understand how mining works. The blocks that are empty because the pools are still processing which transactions were included in the previous block would not have been found period if the pools had waited to validate which transactions were included in the previous block and to change which transactions were to be included in their next block....

I see it staying alive at least as long as 2021 more likely 2028.

that would mean 3.0625 coin sized blocks in 2021  and 0.3828125 sized blocks in 2028

I don't think you understand that I run what is provably one of the best pools on the bitcoin network (along with -ck's solo pool) and I'm the 2nd most prolific developer of cgminer code.
I think I DO understand how mining works :D

Those pools with empty blocks are using the excuse that their pool code and bitcoin code is too slow to wait for validation.
Yet our pool code doesn't do that and indeed does faster block changes than all non-SPV pools.
That would also directly imply that waiting for that validation would mean more orphans.
Yet our pools have less orphans than any of the EMPTY block and SPV mining pools.
Go figure :)