There are still plenty of COBOL programs in vital use out there. 

A bit more seriously, from all saw over the last 15 months, the only prediction that seems to work is based on the log-brownian model, and it says that the expected price at any time in the future is today's price.

The most likely future price in the may be somewhat lower than todays price in linear scale; but, in log scale (which will perhaps be used next year to pick the winner), today''s price is also the most likely future price.

So that was my first choice.  Unfortunately, someone else beat me to it, so I went for a second choice: extrapolating the trend of the last 15 months to April 1st 2016.

And, if bitcoin actually dies before that date, this forum will probably be closed; so it would be pointless to enter "$0" 

Or perhaps to make sure he did not have a chance to move any bitcoins, or give someone the keys to do so.

EDIT: I see that it was the reasons indeed, according to his wife.

Oops, thanks!

Predict the price of Bitcoin on 1 April 2016 - win CBX (Crypto Bullion)
https://bitcointalk.org/index.php?topic=1012254.msg10982182#msg10982182

Rats, there goes my idea.  Well then:

$81.01

Oops sorry, stupid of me...

Great! But you may want to edit the thread title (or start a new thread), to attract more prophets...

insured, in what sense? BTC deposits too, or just the dollars?  Do they say so in their site?  (The ETF will not be insured, they say so in the SEC filing.)

Sorry for the off-topic, but I though that some of you may know one of these guys personally, or both, or him, and might be kind enough to shed light on the issue:
https://bitcointalk.org/index.php?topic=178336.msg10979611#msg10979611
Thanks...

Popcorn excuse from a newly elected board member of the Bitcoin Foundation:
http://www.reddit.com/r/Bitcoin/comments/31e6jh/the_truth_about_the_bitcoin_foundation/

It seems you too jumped into the middle of the discussion?  I am not proposing anything, or trying to convince any miners or users about anything,  I am just pointing out that the common claim "a mining cartel with 51% power cannot change the protocol"  is based on simplistic and optimistic assumptions about what the cartel may want to achieve, how that "attack" would be carried out, and how the community would react to it. 

Claim:
  Even though the front door does not lock, burglars will not enter the store at night through it.

Proof:
  The door opens out, not in.  if a burglar tried to walk through the door, the door would stay shut and he would crash into it.  Since the door is harder than his bones, he would hurt himself badly.  His friends do not want him to get hurt, so they would call the cops to come and arrest him before he gets to the door. QED.

To me, the standard argument used to dismiss the "51% takeover risk" sounds about as logical and convincing as the above, sorry.

Whether big armies are good or bad is not the point.  The point is that, no matter how big or small is the network (or the army), the risk of one part of it taking power and defeating the rest is about the same.  In other words, a bigger network (or army) may offer more protection against attacks from outside, but not against attacks from inside.  There have been military coups in countries of all sizes, from tiny Pacific(!) islands to large countries like Brazil, Pakistan, Indonesia, ...

You jumped in midway through the discussion... More like, "after 2016-03-01 we will freeze the coins of anyone who has not upgraded to our version of the software.  That may cost us a few BTC per day in lost fees, but we will continue making the same revenue from block rewards that we are making now, even if we ultimately fail to impose the switch; all this so that we don't lose 300 million dollars per year because of the halving".

Sigh. Yes:

A man with a gun can poke holes in other people.

He cannot print dollar bills with it.  

However, ...

Oh, I already did, here in bitcointalk and on reddit.  The replies were the same: "the majority miners will not do that because it would render the coin valueless" and "if they do that, the faithful would move to an ASIC-incompatible clone".

Sorry, but the first claim is terribly naive wishful thinking (just look at how cartels act in other markets, e.g. international banks), and the second "defense" would be just a ridiculous form of economic suicide by a small set of irreducible ideologues.

Overstock's 2014 financial report filed with the SEC



(They also had 180 million dollars in cash at year end.)

Overstock's CEO Patrick Byrne on Q4 2014 Results - Transcript

Sorry, I believe that you failed to understand.  All the ASIC and mining installations will remain perfectly usable with the 25 M chain, and would mine it because there would be no other chain that they can mine.

Ater the "Red Button" solution there will be two fully functional versions of bitcoin, but one will have a 300 PH/s network, the other will have a puny CPU network.  Even "hero miners" with older ASIC miners in the attic will be unable to come to the help of the second one.


Whether the attack succeeds or not, the concentration of hashing power in the "Big Bitcoin" network will be the same as it was before the fork point.  The change to the halving schedule will not affect the possibility of double-spend.  In fact, that possibility already is not negligible now. (Imagine that some hacker steals 500 kBTC from the US or Chinese government, who is determined to get them back.)

The risk of double-spend will be much higher in the "Small Bitcoin" CPU-only network, since an external agent could gain majority mining power with a relatively small investment.

You mean, the CEO of Bitcoin will step in, turn the network off, and decide which minority of the miners is the good one? 

Seriously, the defense against a 51% attack cannot depend on a trusted group of core developers, or a "good" minority of miners prevailing over the majority.

Besides, the core developers with the "raid siren button" work for the Bitcoin Foundation, and some of the largest miners like KnC and BTC-China are among its directors and largest financial supporters.  Which side will those devs take?

I don't understand the first paragraph.  Yes, the rebels will control 100% of their puny all-CPU network (which the cartel could probably squash by renting some could computing for a couple million dollars, if it cared to).  But 100% of the old hashpower will be mining the cartel's 25 M chain, just as before the fork; and the rebels cannot do anything against them.  Each client would have to either upgrade to the cartel's software, or upgrade to the rebel's software (or to both, after cloning the wallet); clients who keep the original software will be unable to use their coins.

Yes, this is called "Red Button plan" or something like that.  It is not a defense, or even a deterrent like the nuclear mutually assured destruction; it is just a ridiculous form of suicide.


The problem is that power is asymmetric: a small group of miners can block the network and hold all users' coins hostage, whereas no group of users can stop the miners from doing it without hurting themselves a lot more.

According to the attack plan outlined (which is just one possibility), the 21 M chain would become defunct immediately after the fork, while the 25 M chain would continue working without a glitch. 


There would be no confusion, because any exchange that fails to switch will have its wallets frozen and all BTC deposits and withdrawals blocked.  The coins that are inside the exchanges can be traded normally, because the trades do not involve the blockchain.  When the exchange switches to the 25 M chain, it will find its hot and cold wallets waiting there, and it will be able to execute withdrawals in that chain.  Clients then will have to upgrade in order to use the coins withdrawn.

If the attack succeeds, life will continue in the 25 M chain almost as if there had been no fork.  If the attack fails, and all miners go back to the 21 M chain, people will be able to use that chain again, but their accounts will be reset to the pre-fork state.  Thus, any payments made using the 25 M chain will be cancelled, and there will be real losses (like the double spend against OKPay in the 2013 fork).  This will be another reason why most everybody will want the attack to succeed, once it has been sustained for a day or so and enough people have used the 25 M chain.

There is a third possible outcome: the cartel stops jamming the 21 M chain (e..g because of defections, or "hero miners" coming to the rescue), but only part of the miners go back to it.  In that case the two versions of bitcoin will remain viable; each copy of one's coins can be spent or moved independently of the other copy.  The original price should also split between the two, and the miners will migrate between the chains until either alternative is just as lucrative to mine as the other.  (I wonder if they can be merge-mined?)

This seems to be a common folklore, but is it true?  

I recall an interview with a Chinese miner, made many months ago, where he said how much he kept of what he mined.  Unfortunately I don't recall whether it was 50% or 10%.  Are there other data points?

Assuming that it was 50%, and the guy was telling the truth, and he has been able to keep that fraction in spite of the falling price, and he is representative of all miners, even so the miners must be taking ~450'000 $ out of the system, every day.


Well, I believe that bitcoin is broken in that respect: mining will inevitably become centralized, ane eventually it will be controlled by a cartel of miners.  And the cartel can  do arbitrarily nasty things: not just dictate the minimum fee, or starve competing miners (which everybody knows that they can do, right?), but even force all users and services to accept changes in the protocol -- such as postponing the next halving.  That is one reason why I am skeptical about its longterm success.

(By the way, they could postpone the next halving but speed up all the subsequent ones, so as to preserve the 21 M limit that people seem to be so attached to.)

Discussions of the 51% attack usually start with the tacit assumption that the attacker wants to destroy bitcoin, or do some petty crime like double-spending, that would immediately destroy it.  However, cartels and monopolies do not get created to destroy their business, but to maximize their revenue -- usually by charging far more than they could charge in a free market.