The current scheme for avoiding wiki spam and supporting the wiki is documented at https://en.bitcoin.it/wiki/CryptoPayment

At the per-user page, https://en.bitcoin.it/wiki/Special:CryptoPayment

I see two different payment amounts.  At the top it says:

In order to be able to edit pages on this wiki, you will need to send a payment of at least 0.001 BTC to 1xxxxx


At the bottom it says

Status

To move forward, you will need to send 0.003 BTC to 1xxxxx

So which is it?  Or is "moving forward" different than "editing pages", e.g. a premium payment to move hosting and development forward?

If I send the requested amount in two payments, will that work?

I also suggest that you add some text to alert people to the risk of having their bitcoin addresses linked to their wiki identity e.g. by folks looking for transactions of the right amount just before the initial wiki edit of a newly-trusted user.

(for future reference, 0.003 BTC is about $1.69 at current exchange rates.)

During the upgrade if we want to pause it (e.g. to get some work done), what is the best way to do that?  I'm running on Ubuntu 12.04.

E.g. I ran "bitcoind -daemon"  (I wish I could leave that daemon running and have bitcoin-qt reference it....)

Is it safe to do a "bitcoind stop" in the middle of the upgrade?  Will I lose any work already done?

Or should I stop the process in mid-stride (kill -stop ) and kill -cont it later?

I think most of you are missing the point of Ripple and XRPs.

While currently opencoin has a bunch of XRPs to hand out, note that in the future a "consensus" process can issue more of them.  The goal is for them to NOT be scarce, though they are currently scarce since the distribution has just started and not too many people have gotten their 40000 of them yet.

Why would folks give XRPs away to keep them scarce?  The ripple community's goal (as envisioned by the creators) is not for XRP to be a scarce commodity, but merely for them to be valuable enough that it isn't easy to spam the whole network with new transactions or new accounts.

So don't expect XRP to skyrocket in value.  That's not what they are for.

What are they for?  Like the founders keep saying - they're like stamps to let you exchange other currencies.....

Ripple is about the exchange of other currencies, and ripples/XRP are about facilitating that, not about currency speculation in XRP itself.  As bitcoin itself has taught lots of people, and as Adam Smith said a long time ago, currency is about two things: “value in use” and “value in exchange”.  Folks are viewing bitcoin as valuable for both.  XRPs are designed for just "value in use".

Or at least that is the intent, as I read it.  Ultimately the consensus process (i.e. the community of users) will decide.

Interesting.  Easy to believe, sad to see, but no big surprise.
Of course the OpenCoin folks could just be smart and look for this sort of pattern before giving XRP away.  Hopefully, my pattern doesn't look suspicious

But we also really can't expect the world to be a very fair place.  Note that 40,000 XRP is just 1/250,000 of the overall 100 B XRP that exist, so unless there are a whole lot of very successful scammers out there, this would not be a big effect.

r3NQyByq6KfvnD1PXu3jwGzdsVGn1HEJNq

Thanks - nice site!  Ben Reeves recently noted that it answered my '“Market capitalization” over time'  question at stackexchange: http://bitcoin.stackexchange.com/q/2047/99

But as I noted there I'm puzzled as to why the "unix time" timestamps for the daily data points in the json output aren't for midnight UTC.  Why always 14:55:45 UTC for the market cap page, and 18:15:05 for transaction-fees, etc?

Also, for http://blockchain.info/charts/transaction-fees can you stop rounding off the fees to the nearest BTC?  It's just bouncing around near zero now.

And do you know why there is a huge increase in estimated transaction volume since Nov 16th, to all-time highs?
  http://blockchain.info/charts/estimated-transaction-volume

Finally, can you put in a redirect from the original URL for the site (http://pi.uk.com/bitcoin/...), so old examples posted here work?

I just ran across a formal paper expanding on this idea, complete with a salt, a threat model etc.  See their demo and abstract submitted to
 FC'12 : Financial Cryptography 2012
 http://fc12.ifca.ai/:

Jeremy Clark & Aleks Essex -a demonstration of a simplified version of CommitCoin
 http://people.scs.carleton.ca/~clark/commitcoin/

CommitCoin: Commitments with Temporal Dispute Resolution using Bitcoin
 http://people.scs.carleton.ca/~clark/commitcoin/abstract.pdf

and the commitment itself:

 http://blockexplorer.com/tx/2993c284f0b6838386ddd286af415384560d93cc4e27d25087fd6534f8e0d276

I agree that it is probably better to mix various uses in one block chain which can then be optimized, rather than trying to establish and defend multiple block chains for different purposes.

There is a question about BTCDD aka CoinDD at the Bitcoin StackExchange site:
 http://bitcoin.stackexchange.com/q/845/99

I note that there seems to be a discrepancy in the percentage calculations between the chart shown in the wiki and the value calculated by ABE.  E.g. the ABE result for block 131400, which was also around June 17 2011, was "Cumulative Coin-days Destroyed: 35.1672%", but the value from the wiki graph is about 28% on June 17. The corresponding value on the banana.mine.nu graph is about 900,000,000 bitcoin days.  More info and links to the details are on the StackExchange site.

Does anyone know exactly how the values are calculated by any of these three sites?

I note also that the percentage value seems relatively flat over the last quarter, at least according to ABE.  They
 report it as 36.1245% as of block 145677 at 2011-09-17, vs 35.1627% on June 17.

Does anyone know of a regularly updated graph by percent, rather than the graph of the raw numbers at http://banana.mine.nu/daysdest.html

I figured it would make sense to update the bitcoin wiki with the news that chargebacks could happen.  So I went to

 Dwolla - Bitcoin

and was surprised to see this text.  It was added back on 2011-01-08 in this edit:

 
I wonder what the source for this claim was.

Here is a link about ACH chargebacks

This is actually quite a different thing - it is finding a password which would hash to the same value, if the output of the hash was only 64 bits (really 67, FWIW).

If the password hashing algorithm was really awful, without salt or iterations (i.e. worse than what we had in 1978), these might require similar amounts of effort.  But a modern hashing algorithm like PBKDF2 or bcrypt or scrypt would make things much much harder.

See more on how password hashing should really be done at How to securely hash passwords? - IT Security - Stack Exchange

So far it sounds like a bug in the Android client's handling of very small ("spammy") transactions, which do require a fee to be safe.  Note that the rules are complex, and include not just how many bitcoins were transferred, but how old those bitcoins are, since spammers will presumably find it easier to spam with new coins.


Some detail is given in the wiki:
Transaction fees - Bitcoin

I'm not sure if it is all on the right track, and it is clearly a bit out-of-date.

I wrestled through the non-standard use of little-endian hashes and input values in bitcoin, and dug out the block input which results in this tiny tiny hash output.  I documented it all as an example in the wiki:

  https://en.bitcoin.it/wiki/Block_hashing_algorithm

Here it is in hex:


Note that you have to convert it to binary, hash it with SHA-256 twice, then reverse the bytes to get the value you compare with the target.  Then convert back to hex to match the blockexplorer representation of the hash:

 00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d

I think it was a good show, as is usually the case with the Planet Money team.

At 16:40 into the podcast they talked to Professor Ronald Mann of Columbia Law School who said that it is legal... for now, but also said:

He also doesn't think it will take off, and will die within a few years.

I suggest making comments on that podcast entry about the many other attractions of bitcoin, or at least voting up ones you agree with.
  http://www.npr.org/blogs/money/2011/07/12/137795648/the-tuesday-podcast-bitcoin

I think vanity addresses are cool, e.g. for nonprofits that accept bitcoin donations, among a variety of similar scenarios.

So ByteCoin, I'd encourage you to go ahead with your service, if you really can convince folks that you wouldn't find out their private address.

Well, 67 bits.  I'd say that if a password hash algorithm produced exactly 67 bits (i.e. sha256(sha256(input)), truncated after the 67th bit), we have to date demonstrated a crack of a particular value (all zeros).

Or, we've done something that requires 2^68 work (2^67 * 2 hashes per attempt).

I'd also like to know the cumulative number of sha256 hashes done to date by bitcoin miners, which should be on the same order of magnitude.

One more tidbit: here are the winners over time, with their block height.


000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f 0
000000000009606d829b157912edb060c406b519fb2bfcc1078c196b69c67e49 1430
00000000000243ab3dd422f82638c9651cfc401ac763b2228f00f6abae334f48 11686
000000000000c09b5844620bdec4d533107844efea128a6ec6326dd92f6dc7e6 43011
000000000000b545d467b95ad844b8c718f9b76e9426e4efab7e097ca09a83da 55593
0000000000009f9f9991befc49dc787a190206d1dd32467b687e32157d48c651 60040
000000000000177131355902f9a7a9d94d1f57aba9ef4430bb01123190325977 61068
000000000000013af45c4ac4814ab12a69a6e65a40db0e1e3844fcb2ecaddb24 73373
0000000000000062864d8512b92b2f6a0c2a9edcda82aae03063879b3869d507 89665
000000000000004fa1186f88c245f89757b74b7ef1fa87302ab340b635686c1c 91940
000000000000000834e72c05564b54cc21ac27fb0cbe4ec686bfe607273ad611 101777
0000000000000006acb7899a26faa6290030e25ae41c8b3f62d69809994b89d8 114335
00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d 125552

Ding ding ding - you are a winner!

Though I also speculate that it is the largest number of leading zeros for the hash of any known input.

Here is a list of the top 10 hashes to date, followed by the block number in which they appear.  It is based on the "hashPrev" values of a recent blockchain.  And of course, the first is the made-up value from the genesis block.

[('0000000000000000000000000000000000000000000000000000000000000000', -1),
 ('00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d', 125552),
 ('0000000000000000629981ebad88aafb5856e6663998d1083d74008be66a384a', 133316),
 ('00000000000000011ac23090a91a9297e8cb27c6d81cea9fc429fd37468d509e', 128456),
 ('000000000000000166b3b12f3e8928897fa5241985e75a9d31945dc2d22a39c8', 130557),
 ('0000000000000001e4646f3b4841707b62ecf7412ebc0bdbd2538e745d474a79', 133047),
 ('0000000000000001f2542ad9420bb538ffebd2e872d1dcbed233d07dc5eb0e01', 132103),
 ('00000000000000022d118b8a6b54cf261f3fb854b32f57d70545ad566e4adc7f', 132750),
 ('0000000000000002739d5a374b95e8bd7f5b7c810d07407924385b2181586dc6', 131384),
 ('0000000000000002ed549896e4571ab6ec7d805741038cb8dac97d4c2917c729', 128687)]

Followup question: what is the exact input for this hash?  I guess it would be best to provide it as an easy-to-copy-paste value, i.e. in some standard encoding like base64, so it is easy for folks outside of the bitcoin community to validate it.

You'll have to find a much more distinguishing characteristic than what a simple google will tell you.

I did some digging and came up with this distinguished number:
 00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d

That's the Jeopardy answer.  Just for fun, I'll let you figure out the question.

The periodic postings here and at http://blog.bitcoinwatch.com/ are interesting - thanks!  But I'd like to understand the theory behind them and the choice of technical indicators.  I have found the StackExchange-based Q&A sites to be a lot of fun to use and very good at helping an expert community achieve and share consensus on interesting questions, so I asked this question:

What technical indicators might be appropriate for analyzing Bitcoin currency trading? - Personal Finance and Money - Stack Exchange

Please share your insights - thanks!