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Incident Raises Concerns About a More Formal Spec For Bitcoin

Posted by timothy on from the emergent-systems dept.

An anonymous reader writes: Aberrant treatment of transactions by Bitcoin miners has renewed concerns that Bitcoin as a protocol may need a stronger specification. OpenBSD savior and Bitcoin entrepreneur Mircea Popescu raised this issue back in 2013 that the current attitude of "the code is the spec" was introducing fragility and harming Bitcoin's vital decentralization. While a lot of fuss has been made about the maximum blocksize, perhaps formalizing the protocol and breaking the current mining cartel is a more urgent and serious problem. The debate going on resurrects many of Datskovskiy's early concerns about Bitcoin's fragility including mining as a necessary bug, but a bug nonetheless.

80 comments

  1. decred by Anonymous Coward · · Score: 0

    check out decred instead

    1. Re:decred by U2xhc2hkb3QgU3Vja3M · · Score: 2

      What does Decred have that Bitcoin doesn't? Your lack of arguments for Decred and against Bitcoin doesn't tell us much.

    2. Re:decred by Anonymous Coward · · Score: 1

      Decred has Proof of Work (coin mining, PoW) and Proof of Stake (voting on block validity, PoS). Using PoS majority coin holders could invalidate the errant miners by saying no(voting) to their blocks thus denying them monetary value for work done that does not meet the consensus of the actual coin holders. We have yet to see if this will keep mining cartels from being dicks but it is a step in the right direction.

    3. Re:decred by U2xhc2hkb3QgU3Vja3M · · Score: 1

      So instead of having mining dicks, we would have coin holding cartels dicks.

      Such improvement! Many coins! Much cartels!

    4. Re:decred by Anonymous Coward · · Score: 0

      That is possible I guess. PoS voting in decred requires you to lock your coin. It is unusable for a variable period typically 28 days on average. I would think it possible for an evil cartel to form but it would be much harder as you would have to have majority for the mining hashrate AND the total coin amount. I am not sure the evil cartel could accomplish both.

    5. Re: decred by bistromath007 · · Score: 1

      Yeah, Dogecoin is obviously the best.

  2. How is Bitcoin doing? by samuel.progin · · Score: 2

    Besides this issue, I recently read that the block size debate between 1 or 2 MB is heated. Is it just a small hiccup the the sign the Bitcoin is reaching it limits?

    1. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 0

      Currently Bitcoin is mostly a toy of the Chinese coin-mining cartel.

      Whatever touched by the Chinese, withers. It's in their nature.

    2. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 1

      Serving its purpose: facilitating illegal commerce.

    3. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 4, Insightful

      As opposed to every other currency in the world, ever.

    4. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 1, Funny

      Serving its purpose: facilitating illegal commerce.

      And terrorism.
      And financial instability.
      And slowing economic growth.
      Probably pedophilia too.
      And racism.
      And Trump.
      Did I leave anything out?

    5. Re:How is Bitcoin doing? by Richard_at_work · · Score: 4, Insightful

      It already has reached its (current) limits - you can currently wait up to an hour to have your transaction written into the block chain, which means that at any time during that period the buyer can withdraw the transfer, so you have to delay handing over products until the transaction has actually been written into the block chain.

      Can you imagine having to wait an hour before you can leave the supermarket if Visa didn't authorise a transaction right away?

    6. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 2, Informative

      Perfectly traceable.

    7. Re:How is Bitcoin doing? by GLMDesigns · · Score: 3, Interesting

      As does cash.

      However, unlike cash, bitcoin is traceable.

      --
      If you're scared of your govt then you need to further restrict its powers
      Vote 3rd Party in 2016 and beyond
    8. Re:How is Bitcoin doing? by GLMDesigns · · Score: 3, Funny

      yes. Dice buying slashdot.

      --
      If you're scared of your govt then you need to further restrict its powers
      Vote 3rd Party in 2016 and beyond
    9. Re:How is Bitcoin doing? by mysidia · · Score: 1

      Besides this issue, I recently read that the block size debate between 1 or 2 MB is heated. Is it just a small hiccup the the sign the Bitcoin is reaching it limits?

      I think they want a bigger block, so placement within a block is less scarce, And the network as a whole can do more transactions per second.

      Why not reduce the target from 10 minutes per block to 5 minutes per block, instead, however?

    10. Re:How is Bitcoin doing? by goombah99 · · Score: 1

      Almost like a Check.

      --
      Some drink at the fountain of knowledge. Others just gargle.
    11. Re:How is Bitcoin doing? by vtcodger · · Score: 2

      But how do you use bitcoin to blow cocaine?

      --
      You can't see ANYTHING from a car, You've got to get out of the goddamned contraption and walk...Edward Abbey
    12. Re:How is Bitcoin doing? by Richard_at_work · · Score: 2

      Even before they started to be completely refused as a payment mechanism at UK shops in recent years, cheques were almost always refused at shops if they were not accompanied by a cheque guarantee card which covered amounts greater than the face value of the cheque.

    13. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 2, Interesting

      Interestingly while VISA does typically authorize the transaction right away (although Supermarkets may choose to operate without online auth, for example if they have a telecoms outage)... ... authorization and settlement are separate.

      Authorizations on their own do nothing. No money changes hands, nothing.

      Settlement moves the money but doesn't require authorization. The supermarket can issue a settlement saying "send me $800 of Richard_at_work's money" without any authorization showing you asked to pay them that money. They normally do provide the authorization, but if they don't VISA can (and for a big customer like a supermarket usually will) complete the settlement anyway.

      That's right, the only thing keeping a Walmart from taking every penny out of your credit card is good will. No technical measures are in place to ensure it doesn't happen. If they do it "by accident" and get caught, maybe VISA will slap them and tell them not to do it again. And in theory if they did it a few times, or if it caused a big public outrage, VISA could kick Walmart out and refuse to do any settlements for them. But most likely PR people would come in and smooth things over and assure everyone it will never ever happen again, even though in fact it might.

    14. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 0

      Don't forget having to have 66+ gigs of disk to go through the blockchain which is constantly growing. Skip out on this, and there is a good chance you might find that your precious BTC doesn't exist, as it belongs to someone else who did validate everything, thanks to double-spending.

    15. Re:How is Bitcoin doing? by Anonymous Coward · · Score: 0

      But how do you use bitcoin to blow cocaine?

      Dude, you're doing it wrong.

    16. Re: How is Bitcoin doing? by Anonymous Coward · · Score: 0

      Coz America's interventions around the world have resulted in the spread of prosperity and happiness.

    17. Re:How is Bitcoin doing? by DanielRavenNest · · Score: 1

      With modern currency scanners, you can read the serial numbers off each paper bill. The bank then knows who it hands cash to, and later who it comes back from. That's not full traceability, but it sure narrows down the search problem if you know the endpoints.

    18. Re:How is Bitcoin doing? by DanielRavenNest · · Score: 1

      The 1 MB limit was originally a temporary measure to prevent spam transactions, in the days when actual volume was 10 KB/block or less, and people mined on their home computers. Today we have 1 MB/block of real transactions, and most mining happens on custom chips designed for it. Unfortunately, the people handling the original code implementation have stubbornly delayed any increase.

      Blocks are solved on average every 10 minutes, so at most 1 MB generates 13,333 bps of incoming data, less than a 24 year old 14.4K phone modem could handle. Bandwidth is not the limiting factor, disk space and processing speed to verify a block are. If Bitcoin got much more popular, you would need servers in data centers with big Xeon CPUs, hard drive arrays, and some custom mining chips to verify the transaction stream. Since that's more than home hardware, people could subscribe to a Bitcoin network node on a shared basis to split the cost. As long as there were many such server nodes, with different owners, it would still be decentralized and not subject to central control or attack.

      Beyond beefier network nodes, there are a number of approaches to offloading transactions off the main Bitcoin blockchain. Most of these are not ready for use yet, but people are working on it. The one that is ready is companies like Coinbase, who supports customer wallets and currency exchanging. Any transactions between customers don't have to go on the Bitcoin chain, it's just internal to Coinbase. What you lose then is decentralization. Coinbase can refuse you service or otherwise mess with your transaction, and they have, if they suspect your Bitcoins are from a shady source.

      > Why not reduce the target from 10 minutes per block to 5 minutes per block, instead, however?

      Because each block generates new bitcoins as an incentive to miners to mine. If you shorten the interval, you either have to halve the generation amount, or change the total number of coins which will be generated. This is a big enough change to the "planned money supply" that many people would object. Making blocks bigger was the original plan. The 1 MB limit was only supposed to be temporary.

    19. Re:How is Bitcoin doing? by GLMDesigns · · Score: 1

      Yes it does. As as stores begin to scan bills (checking for counterfeits) then there is the potential to know some mid-points as well.

      --
      If you're scared of your govt then you need to further restrict its powers
      Vote 3rd Party in 2016 and beyond
    20. Re:How is Bitcoin doing? by mysidia · · Score: 2

      Beyond beefier network nodes, there are a number of approaches to offloading transactions off the main Bitcoin blockchain. Most of these are not ready for use yet

      A good reason to not change block sizes, at least not yet.

      If you shorten the interval, you either have to halve the generation amount, or change the total number of coins which will be generated.

      Obviously: adjust the generation amount to correct the discrepancy. This also helps with the problem that Confirmations take too long.

      The 1 MB limit was only supposed to be temporary.

      The protocol has this arbitrary limit. Who is to say that this is only going to be a temporary limit? Consider that changing the size of a block may not be the best way of ultimately achieving the desired objectives, even if someone had suggested it before.

  3. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    It's ironic that you're so butthurt about other people enjoying more sex than you.

  4. Let's call the CEO of Bitcoin! by TheNarrator · · Score: 1, Funny

    We should ask him to get the CTO of Bitcoin to implement the spec and to break his contract with the mining cartel. That will fix everything. /s

    1. Re:Let's call the CEO of Bitcoin! by michelcolman · · Score: 2

      Or just create a new protocol that fixes Bitcoin's flaws. I wonder why nobody has thought of that yet.

  5. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    *then you.

  6. Always fun. by fuzzyfuzzyfungus · · Score: 2, Insightful

    It's always entertaining to see the latest episode of 'Bitcoin: rediscovering the reasons behind the various messy hacks that we dislike about more typical currencies...'

    1. Re:Always fun. by Anonymous Coward · · Score: 1

      The problem, and fix, have no intersection whatsoever with "typical" currencies. It's also entertaining to see the latest episode of "brainless criticism of Bitcoin by people who know nothing."

  7. An important maxim about life. by Anonymous Coward · · Score: 0

    It took me 40 years to learn this.

    Anytime someone proposes a system which ultimately benefits them more than the average person, any claims they make that it will benefit the average person are sophistry designed to get useful idiots to play by their rules, while they do everything they can to get ahead.

    This applies to the most statist Stalinist or the most capitalist Libertarian - indeed, they're both doing the same thing.

    It also applies to the designers and controllers of bitcoin.

    1. Re:An important maxim about life. by Anonymous Coward · · Score: 0

      Getting off your lawn now...

  8. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    "than" was correct

  9. Stop talking about this idiot by Anonymous Coward · · Score: 0

    Stop talking about this idiot Mircea Popescu.

    1. Re:Stop talking about this idiot by Anonymous Coward · · Score: 1

      As much as I dislike the slant typically coming from that bunch (it's not just one guy), their writing is actually more thoughtful than the "this here thing got haxx0red by dem haxxin' haxx0rz, errybody hide!!1!" flood from a collection of vapid "industry" websites that now gets posted here too. At least often enough to keep more of an eye on them than on slashdot.

  10. BEWARE Greek Bearing BitCoin by Anonymous Coward · · Score: 0

    You been warned.

  11. The underlying problem appears grave by goombah99 · · Score: 4, Interesting

    So the underlying problem is there is phenomenological evidence that indicates that for long stretches of time, some cartel can controls 51% of the block chain compute and is withholding submits so it can privately mine them before distributing them.

    If I understand bitcoin correctly, both of those are its fundamental achilles heel, assumed never to happen, and therefore the currency is now subject to manipulation, and thus eventually worthless.

    Or am I wrong?

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:The underlying problem appears grave by Anonymous Coward · · Score: 1

      You're not wrong. "Eventually worthless" depends on the future actions of the various parties though. Another cartel could wrest majority control away from the problematic cartel, which could save it. Also, it's not in the interests of the majority cartel to destroy the currency - you don't get to have 51% of the BTC network without spending a lot of money on hardware. That's an investment requiring a return, which won't happen if the currency folds.

    2. Re:The underlying problem appears grave by MrKaos · · Score: 1

      So the underlying problem is there is phenomenological evidence that indicates that for long stretches of time, some cartel can controls 51% of the block chain compute and is withholding submits so it can privately mine them before distributing them.

      You have to have the most up to date ASIC all of the time or you are at a disadvantage. And electricity. It's a logical conclusion that if someone can control the volume of hardware and electricity thrown at it then they can dominate.

      Maybe the first flaw to be overcome with digital currency is for it to cope with it's own implementation issues.

      If I understand bitcoin correctly, both of those are its fundamental achilles heel, assumed never to happen, and therefore the currency is now subject to manipulation, and thus eventually worthless.

      Wasn't it widley publicized *how* you could manipulate it?

      Perhaps if it can always be manipulated, it is worthless. If you a bitcoin that is worthless you still have a bitcoin. It doesn't have a *value* less than zero, like some other investments might have, so rather than being "worthless" it's "worth nothing" for some period of time until someone says it is "worth something".

      Currency was spent to provide that electricity to create (mine) a bitcoin, which also had value assigned to it.

      Or am I wrong?

      It could be a matter of timing.

      --
      My ism, it's full of beliefs.
    3. Re:The underlying problem appears grave by goombah99 · · Score: 4, Insightful

      Yes one could accept that competing mafia's might be benevolent. But why should they? someone with 51% of the compute can dictate if you can trade bitcoin. That is, if you were to transact something with your keycode, they could prevent it from entering the block chain, thus nullifying your transaction. They can hold the entire system hostage or blackmail individuals.

      --
      Some drink at the fountain of knowledge. Others just gargle.
    4. Re:The underlying problem appears grave by Anonymous Coward · · Score: 0

      Someone with that leverage can prevent you from spending your bitcoin if they choose to. They just extend the block chain omitting your transactions. Even if someone does validate a block chain with your transaction, they can publish a longer one without it. So your wallet has no value unless you pay their monopoly set toll. It's not an open market.

    5. Re: The underlying problem appears grave by Anonymous Coward · · Score: 2, Insightful

      There are many ways to profit from tanking a currency.

    6. Re:The underlying problem appears grave by N1AK · · Score: 1

      Perhaps if it can always be manipulated, it is worthless. If you a bitcoin that is worthless you still have a bitcoin. It doesn't have a *value* less than zero, like some other investments might have, so rather than being "worthless" it's "worth nothing" for some period of time until someone says it is "worth something". Currency was spent to provide that electricity to create (mine) a bitcoin, which also had value assigned to it.

      There's a couple of big issues with this post. Firstly there isn't an investment I am aware of that can have a negative value (shorting stocks, borrowing to buy assets etc are equivalent to betting on bitcoin performance not bitcoin itself). Secondly, the expenditure of effort or value on something doesn't mean the thing has value. I could work to earn some money, spend some more money buying gasoline, and then burn the money and the ashes would not inherit the value of either the components or my effort. Bitcoin doesn't have a value due to the effort expended mining it, it has value largely because of speculation and facilitation of dubious transactions; obviously the ability to spend it on legit things is a part of the value but I'm very dubious that is a a major influence on its value.

    7. Re:The underlying problem appears grave by AdamHaun · · Score: 0

      It almost sounds like Bitcoin would benefit from having some kind of organization to produce and manage the currency. Something like a bank, only more centralized. Perhaps we could call it a... central bank?

      --
      Visit the
    8. Re:The underlying problem appears grave by mysidia · · Score: 1

      and is withholding submits so it can privately mine them before distributing them.

      Methinks the Bitcoin network should add a secondary Blockchain to get rid of this "witholding" nonsense...

      After someone mines a block on the primary chain, they have to submit it to other miners who will immediately start working on mining a block on the secondary chain. If someone else gets their mined block included on the secondary chain first, then all the first miner's with-held submissions are essentially invalidated.

      If there are conflicting versions of the primary blockchain, then only versions consistent with the secondary chain can be accepted.

      If there are conflicting versions of the secondary blockchain, then only versions consistent with the primary chain can be accepted.

      Also, the next block on the primary chain has to include a unique hash from the secondary chain and vice versa, and the next block on the primary chain includes a fixed 5 BTC award for whichever address mined the previous block on the secondary chain.

      Finally, the secondary chain should use a fundamentally different hashing algorithm from the primary chain, AND thus the Primary chain is doubly secured using two different hashes.

      I would suggest the secondary chain use a combination of Block Cipher and Hash algorithms that is very strong, requires a ton of space (e.g. 4 Gigabytes of memory per Hash computation), and cannot be parallelized, and of course, the difficulty should adjust mining the secondary just as with the primary blockchain.

      For example, something such as some hash suite combination;
      INPUT = Data being hashed
      INSALT = Input Salt Hash of the previous block
      a = AES256Encrypt on key=SHA256 of INPUT,iv=SHA256 of INPUT)[0..n], text=INPUT
      b = randomsalt miner's choice
      c = randomkey miner's choice
      d = randomstring miner's choice, Padded with NULs to N Gigabytes
      d1 = SHA256(INSALT+INPUT) + SHA256(INSALT+SHA256(INPUT)) + SHA256(INSALT+SHA256(SHA256(INPUT))) + .... +
      continue to concatenate until length reaches N Gigabytes
      d2 = MD5(INSALT+INPUT) + MD5(INSALT+SHA256(INPUT)) + MD5(INSALT+SHA256(SHA256(INPUT))) + .... +
      continue to concatenate until length reaches N Gigabytes
      d3 = Keccac(b+INSALT+INPUT) + Keccak(INSALT+b+SHA256(INPUT)) + Keccakc(INSALT+b+Keccac(b+Keccac(b+SHA512(INPUT)))) + .... +
      e = (d + d2) XOR REVERSE(d1 + d3) XOR REVERSE(d2 + d) XOR AES256Encrypt(b XOR d3,d+d2) XOR AES256Encrypt(b XOR d2,d2+d3)
      f = BCRYPT(workfactor=20, salt=b, text= a + e )
      g = Keccak512(b, f + e + WPA2Hash(d XOR d2 XOR d3) + MD5(d1 XOR d2) + SHA256(d2 XOR d3) + SHA-3(d1 XOR d3) )
      h = MD5(g)
      i = AES256Encrypt(key=SHA256(randomkey), iv=[0...2], INPUT + randomstring + h + g + f) j = AES256Encrypt( key = SHA256(i), iv = SHA256(i)[0...n], i + e + d + c )
      k = AES256Encrypt( key = SHA256(k), iv = SHA256(k)[0...n], b + a + c )
      OUTPUT = SHAKE256(i + j + MD5(j) + k +j)

    9. Re:The underlying problem appears grave by Anonymous Coward · · Score: 0

      How do we know the primary and secodary solvers are not colluding (or perhaps the same cartel under two different names)

    10. Re: The underlying problem appears grave by Anonymous Coward · · Score: 1

      People with lots of money invest in collectibles because they're pompous twats.

    11. Re:The underlying problem appears grave by Anonymous Coward · · Score: 0

      Yes, and then watch their entire investment become worthless overnight. Greed would likely keep them from harming the perceived value of bitcoins.

    12. Re:The underlying problem appears grave by Anonymous Coward · · Score: 0

      cough... short selling... cough

    13. Re:The underlying problem appears grave by complete+loony · · Score: 1

      The main "problem" in this case; Once you create and publish the details of a transaction, there is no way to invalidate it. Even if it hasn't appeared in the block chain for 2 weeks, you cannot assume it will never happen.

      The rest of TFA is speculation about the how this transaction *might* have been ignored by the mining cartels in order to defraud someone. By hoping that an attempt would be made to create a second transaction, with different inputs, to make a payment to the same people.

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
    14. Re:The underlying problem appears grave by Anonymous Coward · · Score: 0

      What does it mean to have cash?

      Those bits of paper are only representations of faith in the central bank.

  12. Conflicts of Interest by bill_mcgonigle · · Score: 2

    There are competing implementations of full nodes in progress, some more useful than bitcoin-core. Some, like classic allow for bigger blocks, some others are more focused on having a full spec and compatibility.

    There are some who claim that only the core c code binaries can be allowed to run. They DDOS competing nodes and talk trash about every competing codebase, trying to keep Bitcoin out of distros, off devices, etc. They claim that it's because Bitcoin is so fragile that only one codebase may be allowed to touch the Blockchain. Yet other codebases already are and it appears to be working.

    I was interested to read the other day that a couple of the core developers are now funded by very old-world banking interests. It seems so odd to me to see self-proclaimed Bitcoin evangelists fighting against efforts to spread its adoption.

    Meanwhile I saw a bitcoin vending machine in the vestibule of a restaurant the other day, next to the other candy machines, and was happy to be able to seamlessly exchange currencies in a few seconds. The arbitrage between that machine and Amazon makes purse.io a huge boon for local residents.

    --
    My God, it's Full of Source!
    OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    1. Re:Conflicts of Interest by Applehu+Akbar · · Score: 2

      "Meanwhile I saw a bitcoin vending machine in the vestibule of a restaurant the other day, next to the other candy machines, and was happy to be able to seamlessly exchange currencies in a few seconds. The arbitrage between that machine and Amazon makes purse.io a huge boon for local residents."

      How are customers adjusting to the idea of swiping in a Bitcoin purchase, and then waiting an hour for the blockchain to update before their soda drops? How large a crowd accumulates around the machine on hot days?

    2. Re:Conflicts of Interest by Anonymous Coward · · Score: 0

      Lol. This.

      I've never personally stood in front of a vending machine, sighing and thinking "Oh damn, if only this thing took some sort of virtual currency that no one cares about, like Google Wallet or Bitcoin... I guess I won't buy that Snickers bar. That'll show those vending people"

    3. Re:Conflicts of Interest by N1AK · · Score: 2

      I'm pretty sure this may be like the machines you get at Airports where you put in real money and it eventually credits your bitcoin account. Given the delay on locking in a bitcoin transaction no one is going to provide something for bitcoin by vending machine because it would be too easy to take the item and rescind the payment.

    4. Re:Conflicts of Interest by Anonymous Coward · · Score: 0

      How would you rescind the payment?

    5. Re:Conflicts of Interest by tlhIngan · · Score: 1

      I was interested to read the other day that a couple of the core developers are now funded by very old-world banking interests. It seems so odd to me to see self-proclaimed Bitcoin evangelists fighting against efforts to spread its adoption.

      I think it's more of the "coolness" thing - Bitcoin represents everything traditional fiat money isn't. It's independent! It's cool! It's digital! It's not money! No government!

      Now that it's matured though, that counter-culture feel has gone away as it becomes more mainstream. And being mainstream means having to deal with all sorts of issues that you didn't have to worry about. Government interest, regulatory interest, big banks wanting in, etc.,

      All of a sudden, that cool counter-culture it's-not-money thing becomes a mainstream item that starts getting a lot of old-world money interest.

    6. Re:Conflicts of Interest by DanielRavenNest · · Score: 1

      You misunderstand how the Bitcoin Network works. New transactions are *relayed* across the network in seconds. Each network node validates the transaction before passing it on, especially comparing the transaction inputs against the existing blockchain, to make sure the sender had funds to send. If another transaction arrives later, attempting to spend the same funds a second time, it gets rejected. As long as your soda machine is well-connected to the network (talks to a well-connected node), there is a very low chance (about one in ten thousand) the transaction will turn out to be invalid. That's comparable to the rate of fake coins going into the slot, and quite acceptable for a soda machine.

      Bitcoin miners gather up a bunch of transactions, and try to find a hash value that meets a difficult test, based on the contents. That's what a "block" is. Blocks also include the hash from the *previous* block as data. If anyone tries to change the contents of a block (add or change a transaction), it no longer will match the published hash value, so you know it is wrong. If it's an older block, the hash stored in the next block won't match any more. This prevents tampering with past transaction data. Since finding hashes takes significant computational work, the older the block is, the more work would be required to find a new valid hash for a changed block *and every one after it*. Otherwise at some point the contents and hash would disagree, and you would know something is wrong.

      So if you are selling a house for bitcoin, then wait an hour or two for 6-12 blocks piled on top of your transaction. That way you can be sure to a really high probability the payment is final. And closing a house sale takes that long anyway for the rest of the paperwork. But for a soda, meh, 99.99% is good enough.

  13. Misleading link (mining not stated t be a bug) by rocqua · · Score: 2

    No where within site linked to with the text "mining as a necessary bug, but a bug nonetheless" is it stated that mining is a bug. In fact, the word mining is only used twice. It is mentioned only to explain what mining is in the most hand-wavy way possible. Very misleading

    1. Re:Misleading link (mining not stated t be a bug) by Anonymous Coward · · Score: 1

      Except for the part where it's not his article.

  14. Why group mining? by Anonymous Coward · · Score: 2, Insightful

    Why is group mining even a thing?
    It seems to be the source of most buttcoin problems.

    Why not rip it out entirely and change the spec around to balance singular nodes?
    Or put a max nodes per group in effect.

    1. Re:Why group mining? by Anonymous Coward · · Score: 0

      I wish we had an opposite meme for the "get off my lawn" meme.

      "Get off my lawn" is a cliche applied by the young, about the old, to make fun of their futile ways.

      But as you get older, you read statements like the post above, which you know are written by the script kiddies and anonymous teens on the web who pretend to be adults (but their true age comes across in their attitudes and use of language). And you wish you had a way to make fun of them, for their naive and self-embarrassing comments. But there is no good meme for this feeling!

      Grey hairs, I'm asking you...suggestions? :)

    2. Re:Why group mining? by Anonymous Coward · · Score: 0

      A few years ago you could mine with your laptop computer. As bitcoin became more well known, people started to optimize the hardware and created their own clusters for mining, increasing the difficulty for everyone and pushing the smallest miners out, so people with low power systems started to form groups and agreed to share any coins they mined as a way to remain competitive. There is not much that a specification could do to prevent this, it is a natural consequence of competition.

    3. Re:Why group mining? by DanielRavenNest · · Score: 1

      Because the mining reward is only given out once per 10 minutes. If your hardware is an insignificant fraction of the network computation power, you will not win a block in a reasonable time. For example, my graphics card, which I stopped mining with in mid-2013, is 42 MHash/s. The network as a whole is 1.1 million TeraHash/s today. So my expected time to win a block is 500,000 years. I could mine faster if I bought custom mining chips, but it would still be ~500 years per block. By joining a pool, you get a fractional share of each block. Smaller rewards, but more steady.

      "Mining farms" just take this to an extreme. They fill a server room full of mining chips, and win blocks often enough to make a business out of it. Each block reward these days is ~$10,000, and there's 144 blocks per day, so mining as a whole is about $500 million/year.

  15. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0
    • G spot orgasms
    • The Haiku Lover begs
    • More anal sex
  16. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    No, it's "then". Now excuse me while I go vote for Trump. Hoap an Chenge!

  17. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    Eagerly The Haiku Lover Chokes on a large cock

  18. Exactly how bad is the vulnerability? by VikingNation · · Score: 0

    It sounds like the miners in a cartel are gaining unfair advantage to receive reward for mining blocks. Can this be used to reverse transactions or double spent bitcoins?

  19. No by OverlordQ · · Score: 0

    Mircea Popescu is on the same level as Bennett. Not going to read anything by him.

    --
    Your hair look like poop, Bob! - Wanker.
  20. A better idea by Anonymous Coward · · Score: 0

    Just stop using shitcoin and things like it. Inevitably it will just lead you to getting scammed if you stay in the game too long.

  21. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    Faggotry is not sex.

  22. More Formal Specifications Please! by Anonymous Coward · · Score: 2, Insightful

    Yes please a formal specification! I tried implementing Bitcoin but quickly realized the documentation is incomplete and sometimes even incorrect. People keep saying how the protocol is beautiful but honestly these people don't know what they are talking about. It's a big mess to look at that codebase.

    Why do we have specification you might ask? Specifications are a type of contract and as a type of contract they are there to assign blame. It answers the question "Who is violating the specification" when something doesn't go as planned. Which leads me to my next point. It isn't fair to other implementations if the specification is the original Bitcoin client.

  23. Re:This haiku raises a concern about deviant behav by Anonymous Coward · · Score: 0

    "then" you are a moron.