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21  Bitcoin / Development & Technical Discussion / superblock checkpoint architecture on: April 25, 2014, 02:47:21 PM
I've been thinking about ways to make a decentralized checkpoint of sorts.

My purpose here is more to find if anybody has built anything like or this or considered it rather than to suggest it be a practical suggestion for the main chain.

A superblock checkpoint is mined in the usual way, but the rate can be chosen such that the difficulty is some factor 10000 or more times the usual block difficulty.  When a miner gets lucky enough to find a superblock, it creates a normal block but also includes a checkpoint structure of some kind, for example a list of all unspent outputs, or a digest of that list.  The superblock could even behave as a genesis block of sorts in that full clientś and miners might not be required to download previous blocks.  A superblock author could be incentivized by an increased coinbase reward, but the additional proof of work added to the chain from a superblock would not be greater (i.e. superblocks could be orphaned).     

     


 
22  Alternate cryptocurrencies / Altcoin Discussion / LTC / RMB exchange?? on: October 22, 2013, 09:19:02 AM
Can somebody point me to one please?? 

莱特币 / 人民币
23  Economy / Trading Discussion / [Proposal] Pricecoin on: October 17, 2013, 11:30:44 AM
Pricecoin

Abstract


A system for predicting and controlling price for trading on an open market between two assets is outlined.  The system enables a group to act together as a traditional market maker and will enable decentralized exchanges.  

Market Making

Typically, a trade in a marketplace does not significantly move the market price.  However if a market player controls a significant portion of the traded assets, they can move the market.  Market makers move the price with certain cyclical strategies to exploit this effect.  Such moves are not without risk as other large actors or external effects can also move the price.  In the system we outline less risk is present to the market makers, as the ability to participate in market maker strategies is extended to multiple parties.

Overview

To enable multiple parties to collude and agree on price and market strategies requires solution of the distributed consensus problem.  The solution presented is a linked pair of block chains.  

Rather than reward a miner on a chain with units of currency as quantified on a public ledger, we reward the miner with the ability to make a shift in the predicted price of an asset at a given time.  The mining is at essence proof of work hashing, but the result of the hashing is heavily weighted (>1000-fold)  with a proof of ownership of the asset which is under consideration.  A miner (market maker) can direct his hash rate (made available by his proof of ownership) toward one chain or use the other asset similarly to mine on the companion chain.  This is a proof of stake mining system of sorts.  The market pair of assets which we direct our attention must therefore be assets for which cryptographic proof of ownership (digital signature) is possible.

Because block size is smaller we can have much faster blocks.  The difficulty adjustments will similarly be more frequent.  The basic idea is that a rise in difficulty on one chain will linearly mark an increase in sell pressure of that asset at some agreed upon delay.  Ideally the block rate will be fast enough that solo mining remains practical under nominal use characteristics.              

Examples  

For an example, consider a market of bitcoin traded for litecoin.   A simple scenario for pricecoin is when only the communication and prediction aspect is used, leaving it up to the users (nodes) to actually implement the trades.  Client software will simply allow a miner to throw his cash-weighted hashes one direction or the other on the chain pair as the miner wishes to.  The resulting price as listed in the blockchain could represent a futures price of some duration, which all participants will trade on markets accordingly.      

Another way a pricecoin system could be built is as an exchange.  The clients will again need access to both coin blockchains to verify miners claims of ownership and proposed blocks, and the motivation for miners to participate will be also to submit trades, to move the price in a direction they prefer, to accept fees valued in underlying assets, and to keep the integrity of the system.    

An escrow system would need to be carefully chosen at the heart of the protocol.  The block itself created by a miner could include signed transactions to an escrow-ready multisignature address, which the transaction participants can use to add their final signature after checking the transaction and submit to the appropriate network should the transaction be included in a block.  Thus a block will contain multiple transactions at a given price as determined by the block miner (and the limits of the traders offers/bids).  The further submission of the final trade by individuals using the system is likely to be carried out automatically by client software, so that the system is transparent.  This means that as a user, your bid or offer will remain visible in the software, and announced on the network, until a miner agreeing to your trade chooses a price that matches and selects the trade recipient(s) at which point your bid or offer will be matched to another node's bid or offer and the appropriate transaction(s) finalized.  Unfortunately we cannot require proof an exchange on underlying asset chains when we build a block.. after all, we are trying to determine the price at which the exchange occurs.  A pricecoin exchange miner could also act as an escrow for the traders, holdheing funds until TXs on both underlying networks are verified to the proper level, and then creating further TXs to release the funds.  In one flavor of pricecoin exchange, large miners can basically act as bucket shops and so fee incentivization may not be necessary.          


Discussion


Pricecoin networks won't work very well until they reach a critical mass and will need some fiddling or training from time to time.  Incentivising through the use of coinbase minting (new "pricecoins") is not recommended as it will skew the predictive motivations.  The data on the block chains are only useful for maintaining consistency of the network, other than that they do not hold valuable information.  For this reason many public ledger security concerns are no longer so important.  At some point old blocks could be pruned entirely.    

Yes, keyed mining and private pricecoin overlay networks are entirely possible, as are coloured coin trading systems.  Each implementation has its own unique security considerations and peculiarities we won't get into here.   No, this isn't going to help us with gold or fiat.  Yes, I'd be happy to help you build one, send me a message.   Yes there are a lot of details left out here, feel free to fill them in and build your own.  
24  Other / Off-topic / Another way to solve the distrubted consensus problem on: September 16, 2013, 03:47:09 PM

OK, so this might be a little tough to scale into a payment network..  thankfully we have proof of work,
but it's nice to see other solutions waiting out there Smiley 

http://io9.com/5947112/watch-32-discordant-metronomes-achieve-synchrony-in-a-matter-of-minutes

 
25  Bitcoin / Bitcoin Discussion / Schneier in the Guardian: all your coinz is belong to them? on: September 06, 2013, 01:43:07 PM
Here's the relevant quote: 

"Prefer symmetric cryptography over public-key cryptography. Prefer conventional discrete-log-based systems over elliptic-curve systems; the latter have constants that the NSA influences when they can."

That seems like a pretty serious allegation to me..  anything to it folks? 

source:

http://www.theguardian.com/world/2013/sep/05/nsa-how-to-remain-secure-surveillance


26  Other / Politics & Society / Garry Davis, Man of No Nation Who Saw One World of No War, Dies at 91 on: August 14, 2013, 12:50:23 PM
http://www.nytimes.com/2013/07/29/us/garry-davis-man-of-no-nation-dies-at-91.html?pagewanted=all&_r=0


 On May 25, 1948, a former United States Army flier entered the American Embassy in Paris, renounced his American citizenship and, as astonished officials looked on, declared himself a citizen of the world.

Garry Davis, dean of the One World movement, in 1956. He had his own flag and passport, and often his own jail cell.

In 1948, five years before starting an agency to issue passports, Garry Davis distributed handbills in Paris. A stateless man, he was a relentless force behind a movement to erase national borders.

Mr. Davis ran for the United States presidency in 1988.

In the decades that followed, until the end of his long life last week, he remained by choice a stateless man — entering, leaving, being regularly expelled from and frequently arrested in a spate of countries, carrying a passport of his own devising, as the international news media chronicled his every move.

His rationale was simple, his aim immense: if there were no nation-states, he believed, there would be no wars.

Garry Davis, a longtime peace advocate, former Broadway song-and-dance man and self-declared World Citizen No. 1, who is widely regarded as the dean of the One World movement, a quest to erase national boundaries that today has nearly a million adherents worldwide, died on Wednesday in Williston, Vt. He was 91, and though in recent years he had largely ceased his wanderings and settled in South Burlington, Vt., he continued to occupy the singular limbo between citizen and alien that he had cheerfully inhabited for 65 years.

“I am not a man without a country,” Mr. Davis told Newsweek in 1978, “merely a man without nationality.”

Mr. Davis was not the first person to declare himself a world citizen, but he was inarguably the most visible, most vocal and most indefatigable.

The One World model has had its share of prominent adherents, among them Albert Schweitzer, Jean-Paul Sartre, Albert Einstein and E. B. White.

But where most advocates have been content to write and lecture, Mr. Davis was no armchair theorist: 60 years ago, he established the World Government of World Citizens, a self-proclaimed international governmental body that has issued documents — passports, identity cards, birth and marriage certificates — and occasional postage stamps and currency.

He periodically ran for president of the world, always unopposed.

To date, more than 2.5 million World Government documents have been issued, according to the World Service Authority, the group’s administrative arm.

Whether Mr. Davis was a visionary utopian or a quixotic naïf was long debated by press and public. His supporters argued that the documents he issued had genuine value for refugees and other stateless people.

His detractors countered that by issuing them — and charging a fee — Mr. Davis was selling false hope to people who spent what little they had on papers that are legally recognized almost nowhere in the world.

What is beyond dispute is that Mr. Davis’s long insistence on the inalienable right of anyone to travel anywhere prefigures the present-day immigration debate by decades. It likewise anticipates the current stateless conditions of Julian Assange and Edward J. Snowden.

Mr. Davis, who spoke about the One World movement on college campuses and wrote books on the subject, seemed impervious to his critics. In a voice trained to be heard in the last balcony (he was once a Broadway understudy to Danny Kaye), he would segue with obvious relish into a series of minutely reasoned arguments concerning the need for a world without nationalism.

“The nation-state is a political fiction which perpetuates anarchy and is the breeding ground of war,” he told The Daily Yomiuri, an English-language newspaper in Japan, in 1990. “Allegiance to a nation is a collective suicide pact.”

The quest for a unified earth was an objective on which Mr. Davis had trained his sights very early. It was born of his discomfort with a childhood of great privilege, his grief at the loss of a brother in World War II and his horror at his own wartime experience as a bomber pilot.

Sol Gareth Davis was born in Bar Harbor, Me., on July 27, 1921, a son of Meyer Davis and the former Hilda Emery.

Meyer Davis was a renowned society orchestra leader known as the “millionaire maestro”: at his height, he presided over an empire of 80 ensembles — employing more than a thousand musicians — which played at debutante balls, national political conventions and White House inaugurations.

Garry was reared in Philadelphia in a glittering milieu in which the family car was a chauffeured Rolls-Royce and family friends included Bob Hope and Ethel Merman. As a young man he was considered unserious, he later said, known for roguish wit but lacking direction.

After studying theater at the Carnegie Institute of Technology in Pittsburgh, Mr. Davis made his Broadway debut in October 1941 in a small role in “Let’s Face It!,” the musical comedy. He was also the understudy for its star, Mr. Kaye.

Then the United States entered the war. Mr. Davis and his older brother, Meyer Jr., known as Bud, went overseas — Bud with the Navy and Garry with the Army Air Forces, flying B-17 bombers. Bud Davis did not return: he was killed in 1943, when his ship, the destroyer Buck, was sunk off the coast of Italy by a German submarine.

That, and a dark epiphany during a bombing run over Brandenburg, Germany, Garry Davis later wrote, would alter his life’s course.

“Ever since my first mission over Brandenburg, I had felt pangs of conscience,” Mr. Davis wrote in a 1961 memoir, “The World Is My Country.” (The volume was later reissued as “My Country Is the World.”) “How many bombs had I dropped? How many men, women and children had I murdered? Wasn’t there another way, I kept asking myself.”

The other way, he came to believe, was to eradicate conflict by eradicating borders.

In November 1948, six months after renouncing his citizenship in Paris, Mr. Davis stormed a session of the United Nations General Assembly there.

“We, the people, want the peace which only a world government can give,” he proclaimed. “The sovereign states you represent divide us and lead us to the abyss of total war.”

His act, reported worldwide, earned the support of the intelligentsia, including Albert Camus, and of the French public, so recently racked by war. Less than two weeks later, speaking at a Paris auditorium, Mr. Davis drew a crowd of 20,000.

In 1949, Mr. Davis founded the International Registry of World Citizens and was soon inundated with requests to join from around the globe. “We’re bigger than Andorra,” he told The Boston Globe in 1981, when the registry was a quarter-million strong.

Today, more than 950,000 people are registered world citizens, according to the World Service Authority, based in Washington.

Mr. Davis, who lived for long periods in France, appeared on Broadway a few more times in the early 1950s, including in a revue called “Bless You All” and “Stalag 17,” the prisoner-of-war drama. But the One World imperative occupied him increasingly.

In 1953, he founded the World Government of World Citizens. The demand for its documents proved so brisk that he established the service authority the next year.

More than half a million world passports have been issued, though there are no statistics on the number of people who have successfully crossed borders with them. A half-dozen countries — Burkina Faso, Ecuador, Mauritania, Tanzania, Togo, Zambia — have formally recognized the passport. More than 150 others have honored it on occasion, according to the service authority.

Fees for the passport range from $45 (valid for three years) to $400 (for 15 years). The passport has text in seven languages, including Esperanto, the artificial international language.

Carrying world passport No. 1, Mr. Davis spent decades spreading his message, slipping across borders, stowing away on ships, sweet-talking officials, or wearing them down, until they let him in. The newspapers charted his comings and goings:

1949: “Garry Davis Arrested in Paris”; 1953: “Garry Davis Held Again: Arrested When He Camps Out Near Buckingham Palace”; 1957: “France Expels Garry Davis”; 1979: U.S. Court Rules ‘World Citizen’ Davis Is an Alien and Rejects His Passport; 1984: “Japan Expels American ‘World Citizen’ ”; 1987: “ ‘World Citizen’ Announces Presidential Bid.” (It was the United States presidency this time.)

In 1986, Mr. Davis ran for mayor of Washington, receiving 585 votes.

Mr. Davis was arrested dozens of times, usually for attempting to enter a country without official papers. He had canny ways of circumventing authority.

In the 1950s, when France was trying to deport him, he conspicuously shoplifted items from a Paris department store. (His haul, United Press reported, was “$47 worth of peach-colored lace panties, black-silk brassieres, black garter belts, lace petticoats and pink slips.”) He made certain he was arrested.

As a result of his arrest, Mr. Davis was legally enjoined from leaving the country.

Mr. Davis was married two or three times, depending on how one counts. His first marriage, to Audrey Peters, an American whom he courted by mail while detained in France and whom he met for the first time two weeks before their wedding in 1950, ended in divorce. In 1954, the newspapers reported his “marriage” at sea to Gloria Sandler in a ceremony he performed himself; that union, too, was dissolved. His marriage to Esther Peter in 1963 also ended in divorce.

Survivors include a daughter, Kristina Starr Davis, from his marriage to Ms. Peters; two sons, Troy and Kim, and a daughter, Athena Davis, who confirmed her father’s death, from his marriage to Ms. Peter; a sister, Ginia Davis Wexler; a brother, Emery; and a granddaughter.

His other books include “World Government, Ready or Not!” (1984) and “Dear World: A Global Odyssey” (2000). He was the subject of a short documentary, “One! The Garry Davis Story,” released in 2007.

In old age, Mr. Davis was far from idle. Last year, he had a world passport delivered to Mr. Assange, the founder of WikiLeaks, who has been holed up in the Ecuadorean embassy in London.

Just weeks before he died, Mr. Davis had a world passport sent, via Russian authorities, to Mr. Snowden, the fugitive former national security contractor accused of violating espionage laws, whose United States passport was revoked in June.

Mr. Snowden could not be reached for comment.
27  Bitcoin / Legal / MAX KEISER please please please CORRECT your mistake re: confiscation on: April 17, 2013, 04:31:15 PM

Is anybody else really disturbed by these recent quotes from our favorite mad economics reporter? 

He says bitcoins "can't be confiscated".  WTF?? 

e.g.:
http://www.youtube.com/watch?feature=player_detailpage&v=_t39jCXXIrY#t=312s

As it stands this is a large hanging bad omen on the community and seemingly an open invitation to rob Max for everything he's got.  I sure hope that doesn't happen, so please Max --  give the public some clarification on this issue?  Perhaps you mean to say it is more difficult to confiscate bitcoins than some other assets if the holder of the bitcoins has made certain precautions?   





28  Bitcoin / Development & Technical Discussion / Multisig implementation / proof of private key ownership question on: November 08, 2012, 11:12:39 PM

Suppose you create an 8 of 10 multisig address and send a coin to it.

Can you now:

With any 8 of the 10 private keys digitally sign some text as proof of ownership?
What public key(s) need to be made public to do so?

Can you prove you have just one of these 10 keys? 

OK leaving the current BIP as I understand it for now, is there some way a number of keys (say 20) could go into a signature in such a way that the 20 key holders do not know if theirs was one of the 8 ones which make the signature valid for the ownership of the coin? 

29  Alternate cryptocurrencies / Altcoin Discussion / Quantum Money from Hidden Subspaces on: November 08, 2012, 12:21:04 AM
I'm not sure where to put this but I'd like to hear what people think of some of the claims in this paper:

http://arxiv.org/abs/1203.4740


    Forty years ago, Wiesner pointed out that quantum mechanics raises the striking possibility of money that cannot be counterfeited according to the laws of physics. We propose the first quantum money scheme that is (1) public-key, meaning that anyone can verify a banknote as genuine, not only the bank that printed it, and (2) cryptographically secure, under a "classical" hardness assumption that has nothing to do with quantum money. Our scheme is based on hidden subspaces, encoded as the zero-sets of random multivariate polynomials. A main technical advance is to show that the "black-box" version of our scheme, where the polynomials are replaced by classical oracles, is unconditionally secure. Previously, such a result had only been known relative to a quantum oracle (and even there, the proof was never published). Even in Wiesner's original setting -- quantum money that can only be verified by the bank -- we are able to use our techniques to patch a major security hole in Wiesner's scheme. We give the first private-key quantum money scheme that allows unlimited verifications and that remains unconditionally secure, even if the counterfeiter can interact adaptively with the bank. Our money scheme is simpler than previous public-key quantum money schemes, including a knot-based scheme of Farhi et al. The verifier needs to perform only two tests, one in the standard basis and one in the Hadamard basis -- matching the original intuition for quantum money, based on the existence of complementary observables. Our security proofs use a new variant of Ambainis's quantum adversary method, and several other tools that might be of independent interest.


  Authors seem to be unaware of block chain money or think it is irrelevant? 




30  Economy / Economics / Fwd: Infographic: Federal Reserve Notes on: October 10, 2012, 11:46:39 AM
 
Very quick, take a look.

Notice the mining operation being carried out by a red crane Smiley 

http://demonocracy.info/infographics/usa/federal_reserve-qe3/money_printing-2012-2013.html
31  Bitcoin / Bitcoin Discussion / Why bitcoin is doomed: I can't couterfeit them on: September 14, 2012, 05:49:13 PM
https://quantiger.wordpress.com/2012/06/29/why-bitcoin-is-doomed/

tl;dr :
Suppose I have 10 bitcoins.  If I want to loan you money, I have to actually give these coins to you! 
Where's the profit in that?  Ridiculous.   

Note to quantiger:  you can still defraud investors.  Happy now?     

haha! [/captain haddock]
reposted here for the lulz
32  Economy / Services / [Reward] Service Request: Block Chain Voting Site on: August 29, 2012, 10:35:48 PM

I offer a token reward coin to anybody who can set up a verifialble block chain voting site along these lines:

1)    1 coin = 1 vote (or 10^8 votes if you prefer)

2)    votes are submitted as signed text (proving coin ownership) with message including candidate name (or voting subject response) in agreed format

3)     votes publicly verifiable (visible on a website from a text database of all votes)

One somewhat tricky part is making sure there is no double voting which will require some basic taint analysis to make sure new votes arriving  do not represent outputs of previously voted coins.  Other than that, I would imagine this to be a week long project for someone who has set up online wallets or block chain explorers.   

Such a site could be advert supported, or could charge fees; coin based micro-fees could be used to prove the website operators are not throwing out certain votes and to timestamp votes. 

Thanks!  I'll also send you the reward coin if you can find the hole in my logic, thinking this is a good idea.
33  Economy / Economics / "The Federal Reserve System: Mend It or End It?" on: June 15, 2012, 08:51:21 PM

Subcommittee Hearing "The Federal Reserve System: Mend It or End It?"
http://www.youtube.com/watch?v=eU3ygeQUv_4
34  Bitcoin / Bitcoin Discussion / Show me the money on: June 08, 2012, 03:04:25 PM
One of the many awesome features of the public nature of bitcoin is the ability to "show me the money".

In perhaps the most famous incident of this kind when people thought MtGox had lost control of their coins a representative moved a certain amount of money, in effect proving that they still "had the money". 

However this is inelegant and not so secure, and many have done better. 

This post is about asking what you think is the best way to "show me the money". 

I'm looking for a tool that lets me take my private key or wallet.dat, and sign a message saying "Yes I have the money"  in such a way that anybody can verify that I do in fact have the money. 

I'm guessing this functionality is already in Armory or in one of the python or perl tookits out there? 

Whats the best way to do it?  yes, I realize that after the signing of the message the key could become compromised but I think this kind of functionality is still useful. 


Thanks.  1BTC reward for the first post that proves they control some BTC. 
35  Bitcoin / Bitcoin Discussion / The other bitcoin mining on: April 03, 2012, 04:14:31 PM

I'm referring to data mining of the block chain.

There's a wealth of information here that is interesting and valuable for various reasons.  For monitoring the health of the network, testing economic theory, tracking controlling parties, doing psychological studies, optimizing trading strategies, etc.  There are other threads that ask this but I'm going to ask again if people can recommend some good open source tools for getting into this field of research.  I am considering starting with the ABE codebase, are there any other good places to look?  Thanks - -



36  Bitcoin / Bitcoin Discussion / Problems With Bitcoin Part 1: Won't scale for Class 2 civilizations on: March 12, 2012, 07:35:56 AM

The network implementation as is, in particular the delay between blocks, means that the network cannot work on a large scale system.  The network will lose coherency and forks will develop as nodes become separated by distances approaching 10 light minutes.  For reference, sometimes Mars is further away from the Earth than that.  A series of nested chains with increasing delta T targets and difficulties will be required to have a coherent network for interplanetary or interstellar communities.  Lets think ahead folks Wink       

37  Economy / Economics / Ben Fulford seems to endorse bitcoin? Skip to 2:35 on: February 15, 2012, 03:14:57 PM

http://www.youtube.com/watch?v=9I7UT_ILizk

No matter what you think of this guy on other topics you'll probably like the end of this speech Smiley 

Note: 1 year old

 
38  Bitcoin / Bitcoin Discussion / Big coin deal with Jack and Alice: how does it go down? on: October 19, 2011, 08:29:17 PM

Jack Buyer and Alice Seller agreed to use bitcoin on their large deal.  It was rumored to be in the 10-100 kBTC range.  This was well more than an average years salary range in the tropical location they now resided.   

Alice wasn't going make Jack pay upfront before seeing the goods, but to keep things simple they agreed on the price beforehand. 

When Jack arrived Alice had the wares out and safely displayed in a requested location, a location with litttle to no external communications available.   

Jack took a look at the goods, raised his eyebrows, and agreed to pay the price. 

How did the deal go down?
Is there anything Jack and Alice could do to make their deal go down smoothly and with minimal button-pressing or waiting?     


 


Here is one scenario:

Before the deal Jack moves some funds around publicly between wallets to prove he has the cash handy and so she knows the public address of the coins in question.

At the location, Jack hands over the private key to those coins, a QR code he has kept in his wallet or perhaps a base 56 string from memory. 

Alice verifies on the spot that Jack's key matches the public address they agreed to, using an ECDSA sig checker widget on her phone, after cursing at her OCR/VR software a bit.   

At this point Alice trusts Jack, and offers the goods and tells him he is free to go..  however Jack is more suspicious.  He fears Alice's organization and doesn't want to leave them with room to accuse him of anything should the funds move before Alice expects them to. 

So he waits while Alice phones an accomplice, and uploads to her the key.  The accomplice moves the coins to a new address and they wait six blocks while drinking six beers.   








 

39  Other / Politics & Society / OTRA ECONOMÍA YA EXISTE on: October 02, 2011, 06:33:25 PM
from the front lines of the alternative currency movement in Venezuela.

Nothing about bitcoin however... 


Oct 4:  Dia del Trueke

http://rednacionaldetrueke.blogspot.com/
40  Bitcoin / Bitcoin Discussion / Happy free money day! on: September 15, 2011, 06:16:53 PM

freemoneyday.org

You'll have to give it somebody else sorry, I'm not putting my BTC addy here Cheesy
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