No each worker gets a unique blockheader.  If they had the same blockheader they would be duplicating work.  This is important other than preventing cheating.  You want to ensure each worker is working on unique work, any duplicated work is going to result in less than expected returns.  If worker1 attempts all nonces for a specific blockheader we will call "x" and finds no block solution, then having worker2 attempt to do the same thing will always result in no block solution = 100% wasted work.  You could have an infinite number of workers attempt to find a solution for a specific blockheader and they will always fail.  You want each attempted hash to be on a unique blockheader.

https://fastcash4bitcoins.com

Over 290,000 BTC bought and nobody scammed yet.

We currently have a small amount of PayPal funds available but if (when) they run out there will be more funds available tomorrow.   Link to support thread in my signature.

Fixed that for the author.  Markets are just as likely to break out negatively after low volatility and consolidation as they are to break out higher.  I am bullish on Bitcoin long term but these kind of claims are just garbage. 

It is an automatic job in the background.  You should be upgrade to "Jr Member" within 15-20 minutes.

A nonce which produces a hash below the required target only does so for a specific and unique block header.

The pool sends partial blockheader to a miner.  Miner attemps hashes until it finds a nonce such that when combined with the partial blockheader (work) it is below the required difficulty.  That is all you are doing in mining is finding the "magic nonce" but that nonce combined with any other blockheader just produces a random hash.

So pool sends blockheader X to worker 1 (set for 64 difficulty).  
Worker 1 finds a nonce such that the hash of that is H(x+n) meets target for >32 difficulty (but not 64+).
The pool sent blockheader Y to worker 2.  
If worker 2 returns H(x+n) which is the found nonce & hash that worker 1 found it is nonsense/garbage because the pool will take the found nonce n and combine it not with blockheader X but blockheader Y i.e. H(y+n) which just produces a random worthless hash.  The pool simply rejects it.

The same logic that applies to solving a block applies to "solving" a share.  When mining you are looking for a nonce such that the H(rest of blockheader + nonce) < target.  A share is simply a hash which meets a lower difficulty than what is required to solve a block (i.e. difficult 1, 32, or 64 vs 11 million).

A nonce only solves a unique and specific block header.  Change anything in the blockheader and the found nonce produced a totally different hash which isn't going to meet difficulty target.

Using 2FA?

The most complex password (say a 256 bit random key generated using a qRNG) provides no more protection then "password123" against keyloggers, other malware, Man In the Middle attacks and phishing attempts.

PSA to anyone else.  If you don't use 2FA you are just one exploit away from losing all your funds.

Nothing wrong with doing both.  Linux wouldn't have the market penetration that it has without the work of the foundation.  Keeping a massive opensource project on track is kinda like herding cats.  Solid distros are important but what has made Linux an economic force is the fact that it is everywhere (android, routers, set top boxes, media players, etc). 

To the OP I am already a member but if they allow paying membership dues in BTC I will renew mine in BTC.  

From their website

One thing to find out is if there are any ubercart integration solutions for Bitcoin.  If they can drop in integration through bitpay or coinbase and be up and running quickly that may influence their decision.

You must be online for 4 hours (and have 5 posts).  Shortly after those requirements are met (job runs on a schedule in background) your status will be updated to "Jr Member".  When you see "Jr Member" under you name you can post in other forums.

Note the site time will pause if you are not active on the site.  So no you can't login, walk away and come back 4 hours later.  You can see your total logged in time in the upper left under your username.

I doubt 1000 is realistic or useful.  Can you check on the trust worthiness of 1000 or entities?  Unlikely and it is unlikely anyone else could either.  Still I agree we do need more exchanges and that is why the "potential" reduction in MtGox share is important.  When Mtgox holds a 85%+ marketshare it becomes a very difficult barrier to entry.  Exchanges with low liquidity are unattractive and thus they have low liquidity and remain unattractive.  More decentralization lowers the barrier to entry for other competitors.

Orderbook sharing is possible but exchanges would need implicit trust with on another.  That is unlikely to happen with 1,000+ tiny exchanges run by who knows who.  Lets take a simple example lets say just Bitstamp and BTC-E wanted to share order books.  What would happen is when a stamp customer sells say 100 BTC against a BTC-E order there would be an imbalance between both companies.  Bitstamp would be long 100 BTC and short $x USD and BTC-E would be short 100 BTC and long $x USD.  To settle this the exchanges could either establish lines of credit and clear them daily (transfer the net BTC change by BTC network and transfer the net USD by Bank Wire) or they could each deposit funds (both BTC & USD) on each other's exchanges.  Essentially a prepaid model.

Either way both exchanges need to trust that the other one will honor the trades and won't disappear with the other exchanges funds.  The exchanges should also be large enough to handle the loss of the other exchange without affecting customer balances.  Just as an example if BTC-E disappeared and Bitstamp had $10,000 on that exchange they should be able to cover that without reporting a loss to customers balances.  With enough capital and trust I could see a half dozen or so exchanges enter into limited book sharing agreements.

Agreed. As we are seeing various localities have differing requirements on registration, licensing, and business procedures.  It probably makes more sense for a Canadian company to become the best Canadian exchange possible then a mediocre one servicing clients around the world.  Until recently there wasn't enough global volume to justify that but that may be changing.  When you have well run local exchanges with easy deposit and withdraw the entire network becomes more powerful.  A user in Canada makes an easy local funding buys BTC, transfers them to someone in say Hong Kong who uses a local exchange to easily convert back to local currency.

Well saying "cherry picking" isn't accurate.  It is the most recent 24 hours.  Now if I picked a 24 hour period between 03/18/2013 14:32 EST and 03/19/2013 14:31 EST you might have a point.  The fact is the changes at MtGox occured recently.  They didn't occur 30 days ago hence they wouldn't yet be reflected fully in the 30 days figure.    Obviously more time will either confirm this reduction or invalidate it but given how fast things move in Bticoin world waiting until the 30 day state reflected it fully would make if very old news.

Simple ... they didn't.

As pointed out above there are only 10 companies in the entire WORLD that are registered as Money Transmitters in all 50 states*.  This isn't 10 Bitcoin related companies, this is 10 companies period.

* Well 47ish states (excluding states which don't have an applicable license).

Due to various securities laws restricting "general advertisement" we can't publicly discuss this information.  Please send an email to info@tangiblecryptography.com and I will be sure to notify you of any potential future offering.  

THE INFORMATION PRESENTED IS NOT A SOLICITATION FOR INVESTMENT. SUCH INVESTMENT IS ONLY OFFERED ON THE BASIS OF INFORMATION AND REPRESENTATIONS MADE IN THE APPROPRIATE OFFERING DOCUMENTATION.

Um you do you know you can just pay with BTC now right?  Notice lower right hand corner ... "Pay with Bitcoin".  The sale amount is in USD but it will compute the BTC to transfer based on current exchange rate.

You can raise the limit to $10K per day ($50K per month) by upgrading the account to "verified" status.
You can further raise the limit to $100K per day ($500K per month) but upgrading to "trusted" status.
https://support.mtgox.com/entries/20919111-AML-Account-Statuses

Verified isn't to tough but it does involve sending KYC/AML related information and my understanding is Mtgox has a backlog right now.  Trusted is a total pain in the ass in the US as you need not only a notarized document but also to have the notary validated by getting an apostle seal.  This involves a three step process: 1) get documents notarized, 2) send notarized docs to state to be apostled, 3) receive apostled documents back and send to Mtgox.  It took me about 2 weeks (and that was without a backlog) from start to finish.

Bitstamp had no upper limit that I am aware of but you must be verified to withdraw or deposit more than $10,000 USD (or equivalent).  

I would offer the services of my company but we do not have wire capability at this time and keeping funds in stock has been a challenge.  Just curious, have you considered bullion?  Depending on your needs we may be able to work out a custom sale of bullion. 

The OP was 24 hours.  Sorry it wasn't clear.  I just copied the data from bitcointy.  Also yes bitocinty feed isn't complete there are always some exchanges not included.

You can see the reduction over time.


While volume is down across most exchanges, the reduction to MtGox has been outsized.  A comparison of Bitstamp to MtGox.

Bitstamp
318,010 BTC in prior 30 days = 10,600 BTC average per day
6,718 BTC in prior 24 hrs
37% reduction in volume over prior 24 hrs compared to 30 day average

MtGox
3,140,537 BTC in prior 30 days = 104,684 BTC average per day
21,120 BTC in prior 24 hrs
80% reduction in volume over prior 24 hrs compared to 30 day average

MtGox share is under 60%.  I have no ill feelings towards MtGox and don't want to see them "go away" (as others do).  However having exchange volume more decentralized is a good thing for everyone (except maybe Mtgox).  I don't believe decentralized exchanges are viable (at least nothing proposed yet).  For those who want to operate outside the exchange space, OTC is a great concept but major companies aren't going to use OTC.  Imagine tomorrow Newegg accepted BTC and needed to convert tens of thousands of BTC a day to pay bills, suppliers, etc.  They are going to use an exchange and if exchanges can't handle that volume they simply won't accept BTC. MtGox at one point topped 85%+ of total exchange volume and now is below 60%.  Hopefully that will fall even further to say 30% to 40%, MtGox would still be majorly important but they wouldn't be "the" exchange.

http://www.bitcoinity.org/markets/list


We are going to start combining quote feeds from all exchanges and using the "gobal exchange rate" in our pricing models.  

In their guidance letter (and in the exemption sections of the definitions of MSB & MT) FinCEN clearly indicates that an entity buying goods or services* for Bitcoins is not a MSB and that if money transmission occurs as a result of the sales of goods & services one is not a MT.


* Don't try to be foolish and pretend you are selling the "goods" of a $100 bill for BTC and thus not a money service business.

Protest self delete.  Noticed author is engaging in pointless censorship of other posts.  I won't add legitimacy to a non-discussion.

The dust threshold is a variable, there is no minimum (or maximum) just a default.  The default value in v0.8.2 is 5430 satoshis, that default will likely be changed in future versions.  The min mandatory fee (on low priority txs) for example has been changed 4 times in the history of Bitcoin to accomodate increasing value.  

Also (even in the absence of future version) any miner can change the dust threshold by changing a single line in the config file. Right now this very second a miner could (if they chose) run 0.8.2 with a dust threshold of 1 satoshi if they felt the default of 5430s was too high.  They could also run with a dust threshold of 8196s (~$0.01 at current exchange rate) if they felt the default was too low.

Once again the choice of 2^32 was arbitrary.  The block header has a 32 bit nonce and given computing power available at the time (unoptimized CPU mining) difficulty 1 was acheiveable by roughly a dozen or so nodes so it seems that likely factored into the starting difficulty.  Bitcoin could work just as well if the difficulty was 48 quadrillion, initial difficulty was 4 billion and difficulty directly represented the number of hashes required.   It is a completely arbitrary number really only useful in comparing changes in difficulty.  If I can mine ~1 BTC per day on existing hardware and difficulty doubles I can expect to only mine ~0.5 BTC per day.  If difficulty fell 90% I would be able to mine 10 BTC on the same hardware.

BTW:  I really wish that regardless of how difficulty was computed, that Satoshi had used a 64 bit nonce value in the block header.  It would have greatly simplified the mining protocol.  Maybe simplified isn't the right would but it would have been more elegant than the nonce + extranonce (in coinbase) "hack".