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1821  Economy / Speculation / Re: ****$10**** on: August 11, 2012, 08:04:24 PM
Okay, here's the daily plot with error bars. They represent ±1 STDDEV.
1822  Economy / Speculation / Re: The Weekend Dip Myth on: August 11, 2012, 07:50:58 PM
So many people are waiting for the weekend, that it is now the mid-week dip. It goes great with potato chips.
I just debunked this myth... I'm sure it's because so many people believe in the "mid-week dip" that the weekend dip has been delayed. The price now goes down on Monday and Tuesday, and shoots up Wednesday to Friday.
1823  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 11, 2012, 07:47:12 PM
1824  Bitcoin / Development & Technical Discussion / [BIP] Full Autoupdating Node (FAN) for merchants on: August 11, 2012, 07:46:13 PM
Disclosure: this proposal likely has many flaws. Please point them out, but read the full thing first. Thank you.

In Satoshi's original whitepaper, he detailed a type of node that verifies only block headers. This type of node is useful for merchants who cannot afford to run a node that requires updating, as it can accept hard-forked blocks that don't match its rules. However, such a node has several disadvantages:

  • The quarantine attack is lethal against SPV nodes, while only double-spending is possible against full nodes.
  • If enough of the network switches to SPV nodes, miners could theoretically form a cabal to generate extra profits as fees.

These disadvantages are problems for merchants, who cannot afford to be the target of an attack. As a result, many merchants stick to full nodes. These, however, have their own share of problems:

  • Blocks larger than 1 MB will be rejected if the merchant cannot update the node.
  • Blocks with new transaction styles that utilize newly reenabled or added script codes will be rejected.

As a result, most merchants are left with no option but to run a full node that must be periodically updated. This is a problem for many; as it implies necessary downtime or extremely complex shenanigans.

However, it is possible to design a node that is neither victim to the attacks that an SPV node is vulnerable to, nor is hindered by the static nature of full nodes. Such a node is identical to a full node, but with some differences:

  • The node will accept any valid block, but if a short block is available, prefer it to the long one.
  • The node will not process scripts. Inputs and outputs are processed as normal for all transactions, but scripts are left alone.
  • The node will keep a log of all authorized transactions leaving its wallet.
  • The node will reject any blocks with unauthorized transactions leaving its wallet.
  • (Hashrate Slow) If (valid) block timestamps indicate that 2 of 4 consecutive blocks have been much slower than usual, the node tells the processor to wait for 12 confirmations instead of 6 confirmations. If more than 70% of the past 6n−2 blocks have been much slower than usual, the node extends the wait time to 6n+6 confirmations.
  • (Hashrate Freeze) If the node senses that more than 70% of the past 22 blocks have been much slower than usual, it issues warnings and tries to verify everything as a full node. The wait time is capped at 30 confirmations (5 hours), but because of extensive verification, the node will likely reject all the blocks anyways.

Notice that this node does not save any space for the merchant; the blockchain still needs to be downloaded in full. Transaction verification is done as normal, except that the scripts (including the signatures) are not verified.

Each problem and why FAN nodes are a solution is outlined below.

The quarantine attack is lethal against SPV nodes, while only double-spending is possible against full nodes.
Assume the node is quarantined. The attacker must issue a block containing theft transactions from random addresses to the merchant to exploit the merchant in any more lethality than a double-spending attack (which full nodes are also vulnerable to in a quarantine situation). The attacker has a lot of time to exploit the merchant, but no attack is likely unless the attacker controls a large portion of the network.

If the "much slower" curfew is taken at 40 minutes difference between blocks, the attacker is not likely to be able to actually mine a block that is faster than 40 minutes from the last. However, the attacker could fake the timestamps. Because the median of the past 11 blocks is valid (as the attacker would simply be wasting time if they did not initiate the quarantine directly), and the merchant's time should be accurate, the attacker's only optimal strategy is to timestamp the first block they mine as distant as possible (2 hours ahead of the actual time). As this block is "much slower", the attacker only has 160 minutes to mine the next block (otherwise, they would activate the alarm), 200 minutes to mine the next 2 blocks, and 240 minutes to mine the next three blocks. The chance of this happening is extremely small even at 5% of the network: the success rate is 1/5. As these blocks are simply getting wasted, and whether the node is actually quarantined is hard to determine, the random spending attack is not feasible.

Therefore, only a double-spend attack is feasible on a FAN node that is quarantined, giving it identical security to a full node.

If enough of the network switches to SPV nodes, miners could theoretically form a cabal to generate extra profits as fees.
This requires a more distributed approach. Assume that all BTC are in the hands of people who run either i) a full node or ii) a FAN node. The only way for miners to trick nodes into thinking that the fees for transactions are very high would be to "sign" the transactions from random addresses, sum the outputs to very little, and hope that FAN nodes believe the block as legitimate. However, when the FAN node that owns the outputs that are being stolen from receives the block in question, it will reject all blocks that build on that blockchain. Additionally, all full nodes will reject all blocks on that blockchain by default. Because so many nodes have rejected that blockchain, the relaying of rogue blocks will grind to a halt, splitting the rogue miner cabal's organization and restoring the original Bitcoin blockchain as the FAN node-accepted one.

Because such an attack will almost inevitably fail, no 51% of the network's miners will form the cabal in the first place. The maximum extent of damage is simply temporary isolation from the main blockchain before other FAN nodes relaying the blocks stop doing so. The cost of such an attack is too high to be feasible.

Blocks larger than 1 MB will be rejected if the merchant cannot update the node.
A miner cabal forming to create a chain of short blocks is the only issue here. Such a miner cabal cannot earn any money, and in fact is likely losing money due to fees. The damage of such an attack is isolation from the main network, and can lead to another attack, but at no further advantage than beginning the other attack immediately is present. Such a preemptive attack is possible against full nodes too, as it requires 51% of the hash power anyways.

Blocks with new transaction styles that utilize newly reenabled or added script codes will be rejected.
Scripts are not checked by FAN nodes, so this problem is resolved completely.
1825  Alternate cryptocurrencies / Altcoin Discussion / Re: Alt Chains are the future on: August 11, 2012, 06:21:03 PM
Quote
Alt Chains are not the future
FTFY.

"It is difficult to make predictions, especially about the future"  Wink

FTFY.

Alt Chains refers to a group of cryptocurrencies excluding Bitcoin, while the future refers to a timeframe. Therefore, Alt Chains are distinct from the future.
1826  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 11, 2012, 06:18:30 PM
2240: 1/9375 done (0.01067%)


Counted so far:
2240

Not yet counted:
4480
6720
8960
11200
13440
15680
17920
20160
22400
24640
26880
29120
31360
33600
35840
...many more...
20993280
20995520
20997760
21000000
1827  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 11, 2012, 05:02:24 PM
1828  Other / Off-topic / Re: BIBINKA WORD GAME! on: August 11, 2012, 05:00:17 PM
Fat Tay Choon went to the Mining Academy in Brazil, east of Satoshi's yurt, where Gavin was kidnapped by the CIA's goons and forced to pretend faking an anonymous decentralized biscuit—better than all the fish in the Pacific Ocean—but also to defray leeches intelligently with ECDSA fighting qubits for 16.8 dree12, or Phinnaeus must fling toilets towards psy‐ops, without potato smoothies mixed with fried chicken wings from BitMunchies.com, urbanchickennj.com, and Popeye's Bitcoin wallet which deleted Satoshi's premine
1829  Other / Politics & Society / Re: My suggestion to environmentalists. on: August 11, 2012, 04:59:02 PM
My goal is eventually start Marscoin since the network lag would make BTC mining on Mars impossible.

Idea: Locate Bitcoin miners in space (iiiiin spaaaaaace!), at some relatively central Lagrange point, and use it for interplanetary settlements or transfers of wealth. Each planet, then would have its own coin, which you would then convert into when you land. Perpetual travelers could just keep their funds in Bitcoin, or convert small amounts as needed.
Just like how currency works now. It hasn't changed for millennia, and aside from a 10-20 year range where Bitcoin will dominate, eventually different planets will have different currencies again.

Don't get used to Bitcoin being the universal currency, because that's about to change.
1830  Economy / Speculation / Re: The Weekend Dip Myth on: August 11, 2012, 04:55:11 PM
So when does the weekend dip happen sat? sun?

lately it's been friday, thursday, wednesday, and sometimes even as early as tuesday.

It's been theorized that at one point the weekend dip will be up to 1 week earlier than expected and therefore there will be twice as hard a dip.
No, Wed-Fri are all strongly up. Mon-Tue are down. This is because people fail to anticipate the weekend dip, possibly the most reliable indicator of price-time correlation. In fact, the weekend dip has been delayed because so many people believe that it is a myth.



1831  Other / Meta / Re: On "NEW articles in Press Forum" on: August 11, 2012, 01:01:25 AM
This remains unresolved, and the thread in question remains active today. The OP of a stickied thread should not be misleading. I request that at least the OP be edited to remove all falsehoods. If no action is taken in the next few days, I will report the post to a moderator for appropriate intervention.
1832  Other / Off-topic / Re: Walking from England to Frankfurt in Germany on: August 10, 2012, 11:32:16 PM
I was thinking I walk like 3mph, 10 hours a day, so 30 miles a day and it's like ~450 miles, so 15 days?

I was thinking it might not be possible, if, roads are joined by motorways and stuff that you cant kinda walk on?

Many of the main roads won't have a footpath at the side, so you will generally use the more minor older roads which have less traffic and are also more interesting to walk on.
Don't worry, there's always this.


Just hold it behind you, and then enjoy freedom to walk anywhere.

On the way, also buy some of these as stickers:


1833  Other / Politics & Society / Re: Max Keiser - "Libertarians are Intellectually Lazy & Idiots" on: August 10, 2012, 11:14:11 PM
Quote
To answer your scholastic question about the needs of human nature I'll refer to Maslow since he is the simplest to argue. As long as physiological, safety, interpersonal, and esteem needs are met, people will thrive. It should be our goal to create a community that fosters these to the best of our ability. The rewards for doing so will be ever improving technology.

It takes more than this. Without the right attitude most people will just party or do what everyone else does to get by rather than work towards improving themselves and their environment . Do the methods used to provide for peoples basic needs encourage them to be curious and productive? If not, then it may not be worth it.
Scientifically disproven argument. Besides, I didn't posit a method. Read a few books about experimental psychology.

Well then the science disagrees with what I observe in my every day life. Also, I didn't say you did posit a method, I was just putting the issue forth as something to be considered. Dismissing what I said because it has been "scientifically disproven" would be unwise.

"Science" is wrong more than right. I have a degree in psych, I think it is mostly people arguing about various opinions (slightly better than "philosophy"). The field is valuable in that it provides phenomena to be explained by the more "bottom-up" approaches, but I wouldn't take the aspects of it that make it into pop culture that seriously. Using the psych literature as the basis for public policy is foolish. Sure, use the information, but don't treat it as some kind of infallible truth.
OK then real life examples. Most great inventors, artists, authors, etc. in history lived on a pension of some sort. They were supported by family wealth or at the amusement of an aristocrat. People struggling to survive don't think grand thoughts. Speaking of which, I must now bow to my master for a few hours.
I would agree. I would just change the original wording from "[if needs are met] people will thrive" to "the ability of people to thrive is facilitated by having their basic needs met". In other words, having basic needs met is necessary but not sufficient for thriving.


The entire right column of that is not "needs". Those are Internet resources that do nothing more than waste time that could go to proper socialization.
1834  Other / Politics & Society / Re: The purpose of life and the goal of a perfect society on: August 10, 2012, 09:03:39 PM
Here's an interesting thought experiment.

What if we farm the isolationists? Sentience has a fuzzy definition, and by time we meet alien life they may be more similar to animals than humans. Maybe they use some tools from time to time, communicate with each other, have families, or some other things, but otherwise resembles animals. Would it be "right" to, because they are clearly incapable of resisting, put some in a zoo and farm the others for a valuable resource (say, their bodies produce diamond from carbon)?

Crimes of ignorance can be forgiven, I think. But to avoid this, we should find a solid definition of sentience. (note, this may mean we're not the only sentient species on the planet)
Uh-oh. That's opening up many cans of worms.

On the topic of sentience, I'd put forth Theory of mind as the key qualification of sentience. It can be tested for, and most animals do not have it, only some great apes (including homo sapiens of course) and interestingly, dolphins exhibit it.
(emphasis mine)
How?

Well, obviously, the methods are going to change for each species, but here's the way they do it with chimps (and human kids):

Give the subject two pairs of sunglasses, of differing colors, say, one blue, one yellow. Key is that they are easily distinguishable. One of these pairs of sunglasses is totally blacked out. You cannot see out. Demonstrate this to the subject. Then, give the sunglasses to two people, each of whom has treats for the subject. Observe which treat-giver the subject approaches.  Subjects with a theory of mind will always approach the treat-giver with the sunglasses that allow them to see, and subjects without a theory of mind will approach treat-givers at random.
It's trivial to make a robot that can do that. Sentient robots is a problem.
1835  Other / Politics & Society / Re: The purpose of life and the goal of a perfect society on: August 10, 2012, 08:48:04 PM
Here's an interesting thought experiment.

What if we farm the isolationists? Sentience has a fuzzy definition, and by time we meet alien life they may be more similar to animals than humans. Maybe they use some tools from time to time, communicate with each other, have families, or some other things, but otherwise resembles animals. Would it be "right" to, because they are clearly incapable of resisting, put some in a zoo and farm the others for a valuable resource (say, their bodies produce diamond from carbon)?

Crimes of ignorance can be forgiven, I think. But to avoid this, we should find a solid definition of sentience. (note, this may mean we're not the only sentient species on the planet)
Uh-oh. That's opening up many cans of worms.

On the topic of sentience, I'd put forth Theory of mind as the key qualification of sentience. It can be tested for, and most animals do not have it, only some great apes (including homo sapiens of course) and interestingly, dolphins exhibit it.
(emphasis mine)
How?
1836  Other / Politics & Society / Re: My suggestion to environmentalists. on: August 10, 2012, 08:14:05 PM
My suggestion:
It's going to get hot and dry, then we are all going to starve. Enjoy the last days of humanity.  Cheesy
The odds of turning things around must be less than 1 in 10,000? There is not even a theoretical way to address our problems, let alone a solution.



Leave the damn thing be for a few hundred years, it'll find equilibrium again. Next time try not to fuck with it so much.
Ah, Mars. A even more delicate planet for us to mess up. Honestly, better to go somewhere we probably can't mess up if we tried. Coincidently, there's a nice place to live that's also probably the third-easiest heavenly body to get to. We probably couldn't mess that up for a while. Maybe too easy to get to...

Something like this.
1837  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 10, 2012, 08:06:25 PM
1838  Other / Off-topic / Re: BIBINKA WORD GAME! on: August 10, 2012, 07:49:25 PM
Fat Tay Choon went to the Mining Academy in Brazil, east of Satoshi's yurt, where Gavin was kidnapped by the CIA's goons and forced to pretend faking an anonymous decentralized biscuit—better than all the fish in the Pacific Ocean—but also to defray leeches intelligently with ECDSA fighting qubits for 16.8 dree12, or Phinnaeus must fling toilets towards psy‐ops, without potato smoothies...
1839  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 10, 2012, 07:38:46 PM
1840  Other / Off-topic / Re: Let's Count to 21 Million with Images on: August 10, 2012, 05:55:45 PM
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