The storms in Molvania caused problems with the block harvest last week. Some of the blocks were found to be infected with weevil bits. The resulting loss of confidence caused the short-term price drop.

That's not actually a long time for a design decision with long-term consequences. Because of not rushing into this in 2011, it has been possible to improve on some of the earlier designs.


As it happens, I do maintain a large body of PHP code that is not well covered by unit tests. As a result, I almost always make only the most conservative changes.

But when something (a) is important, (b) has long-term consequences, and (c) has the potential for a cleaner but less-conservative change, I do my best to find the time to make the change that is cleaner in the long-term. When I can't manage that, I always feel a little bit ashamed of my code.

Although I contribute to the Bitcoin community in many ways, I've never contributed a line of code, nor am I currently mining, so I haven't earned any right to have a say in this. All I'm hoping to do is to clarify some of the issues so that everyone can feel comfortable with the decisions made by those who are entitled to make the decision. No-one should be left with the impression that any issues were overlooked or misunderstood by anyone making the decision, so I appreciate the clarifications here and elsewhere.

Well, exactly. The design of BIP 16 is safe. A bug-free implementation of BIP 16 is also safe. But in the presence of a bug, an additional facet of the system is exposed to a possible exploit. So BIP 17 has an advantage here.


Thanks for this explanation. The limit of 1000 can, of course, be eased in the future. If BIP 17 puts fewer bytes into the block chain, the potential for easing any future limits (not just this one) is greater, so BIP 17 surely has a slight advantage here.


Trying to break things can help to make them more robust


OK thanks for that unambiguous statement, which neutralises the rumors and makes this a total non-issue. I've edited my earlier post to reflect this.

What are the substantive issues? Here are how I see them:

1. It's prudent to avoid executing data from the stack. Why? Because you have a scripts that manipulate data on the stack. Obviously the system is designed so that scripts can't manipulate the data that is going to be executed. But if there is a bug, you have all the pieces in place for an exploit. The script doesn't have opcodes to manipulate off-stack data, so Luke's implementation seems safer.

2. Supporters of BIP 16 claim that it allows 5-10 times more headroom before block size limits are reached. Supporters of BIP 17 claim that it puts fewer bytes into the block. [Edit: Gavin has explained the headroom issue, but BIP 17 still seems more scalable to me because it puts fewer bytes into the block chain.]

3. It's clear that both BIP 16 and BIP 17 transactions can be spent by others if those transactions are broadcast before 50% of the mining power (plus a safety margin) supports them. It's also clear that the BIP 17 transactions are easier to spend in this situation. However I think this is a non-issue because (a) mining power will quickly rise above 50% once consensus is reached, and (b) who is going to broadcast these newfangled transactions before the mining power is there to support them?

3. Gavin needs to say whether it's commercially relevant to his current work project. [Edit: Gavin has made it absolutely clear that BIP 16 is not driven by any commercial pressure, so as far as I'm concerned this is a non-issue and the rumors can be ignored.]

4. BIP 17 "feels" like a more general approach to the problem, and BIP 16 "feels" a bit more like a special-cased design change.

5. BIP 17 "feels" like a less-developed solution, and BIP 16 "feels" like one that has already had a little more contemplation.

Of these 5 issues, I think only (1) and (2) are of any real consequence.

There's no need for a rush decision. In time, and with further calm-headed discussion, support may gravitate towards BIP 16 or BIP 17, or perhaps a BIPxx will emerge that is superior to both.

It doesn't matter if this takes another six months to get this right.

That's certainly very interesting, but...


The security of the design is easy to prove, and the security of a naiive implementation will be fairly easy to prove, but exploits will target bugs within complex, performance-optimising implementations.

The intractible problem with Keynes is that you can never tell when the cycle begins and ends until after it has happened. At any instant, you don't know how much of the growth is the underlying steady growth, and how much is illusory cyclical growth.

Gordon Brown made a big noise about balancing the budget "over the economic cycle", but in the later years of the credit-induced boom he was already increasing the government deficit because he thought those were the leaner years of the cycle, when actually they turned out to be the fattest. Almost no-one (and certainly no Keynsians) challenged him at the time.

Max Keiser was encouraging people to crash JP Morgan by buying physical silver (so that JP Morgan couldn't meet its futures contracts). Max didn't have enough influence over his audience to actually achieve his goal.

Having said that, if Max Keiser only gets ten thousand new (and active) bitcoin users by the end of next year, it will still have a big effect.

No that's not true. Satoshi set the initial difficulty of "1" so that it would generate less than 6 blocks per hour. He didn't want to generate a lot of blocks until more people got involved.

I can't remember the starting rate, and I can't find a reference to it right now, but I'm pretty sure it was less than one block per hour.

After a while, there were enough people generating that "6 blocks per hour" was reached at the starting difficulty of one, and from that point onwards the difficulty "auto-adjusted" to try to maintain that target rate.

This stuff is taken seriously by academics.

The first Colloquium on the Law of Transhuman Persons was held in Florida in 2005. One of the pieces was about a computer that started moonlighting as a Google Answers Researcher (back in the days before Google cancelled that service) in order to earn enough money to pay its fees. Just as it was about to have its plug pulled, it found a host in a different legal jurisdiction...

More here, from a 2007 blog post:
The Transhuman Google Answers Researcher

Thank you for organizing, promoting, and managing this fundraising, molecular.

Bitcoin was mentioned briefly twice in the paper edition of The Times today (7 December). The mentions were on pages 14 and 15 of the Raconteur supplement on the future of mobile payments.

The Raconteur supplements lean towards advertorial, and are only included with English editions of The Times. The supplement will soon be archived online here:

Raconteur Archive
http://www.raconteurmedia.co.uk/ARCHIVE.htm

It's not much of a mention, and there is a typo (the highest Bitcoin exchange rate was given as $432 instead of $32), but it's the first time I've seen Bitcoin mentioned in the paper edition of a major daily newspaper.

What Rand says is valid enough, but it misses the point. What most people mean by humility is not self-abasement but rather an absence of pompous self-promotion.

When Winston Churchill (reportedly) said "We are all worms, but I do believe I am a glowworm" he was not benefiting from his lack of humility, he was just being a pompous wanker.

And when Oliver Herford (reportedly) wrote "Modesty is the gentle art of enhancing your charm by pretending not to be aware of it", well, he might have had a message there for you, Atlas.

Maybe sell the BTC when/if Max calls in the pledges.

Gubment taxes Amazon more in the future = people buy from Amazon China instead.

Smart gubments would cut some gravy trains and get rid of the state taxes instead. Ain't gonna happen though.

Dwolla doing their own block chain, with easy exchange to/from fiat? It would be entertaining to watch that unfold.

No, not that forum. Those in the know have the unlock code for the exclusive exclusive forum.

So how do you handle a compromise between food and poison?

In the long term, the price of a BTC is likely to have an overall upwards drift. Therefore, if the heatmap is in USD, data from the early years will probably become invisible.

On the other hand, there are already 7.6 million BTC, and the total quantity won't rise above 21 million BTC, so in the long run the BTC volumes will make for consistent charts. (I admit it's not quite so simple, because active traders are exchanging the same coins over and over again.)

Another reason to prefer BTC to USD is that the choice of USD is somewhat arbitrary. Over time, BTC exchange might shift towards other currencies such as sterling, the euro, or renminbi. But BTC will always be a useful and relevant figure, no matter what currency the BTC are being exchanged against, or by how much the fiat currency has inflated.

It makes sense to lose faith. Believing in something because of "faith" just means believing in it because you want it to be true.

If Bitcoin users were losing reason, that would be something to worry about.