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1441  Local / India / Re: How Do We Serve India, 1/5th of the Global Population, with Bitcoin? on: March 25, 2013, 06:42:35 AM
Did you get any takers yet? If not I'll do it.

Someone has responded and is filling this transaction.  The payment (of 1,500Rs) was made and the next step is for Milaap to send the gift card via e-mail, so that's where this transaction is at for the moment.
1442  Bitcoin / Bitcoin Discussion / Re: Instant confirmation using only the blockchain. on: March 25, 2013, 04:48:42 AM
To be clear, I'm not trying to get around the small fees, only envisioning the speeding up of the process for the vendor and patron on a single transaction from a single wallet.

A credit card authorization ensures that the customer's credit account is open, is in good standing, and has sufficient funds to complete the submitted transaction.  If the card passes these checks, the issuing bank will place a hold on the funds for the amount of the authorization.

When looking at your credit card statement online you might see these transactions as being marked "pending" or "authorization hold".

Unless the transaction was "authorization only" (e.g., in the rental car scenario) the "pending" transaction is at some part of the several-day process for transferring funds from the customer's charge account to the merchant's bank account.  This is known as settlement.

Bitcoin doesn't have this same process flow however.  You could approximate the 0/unconfirmed being the "authorization" request and a transaction reaching six confirmations as being similar to "settlement", but these cannot be used interchangeably.

When the credit card authorization is made, the card issuer has the "master node" which is the authority as far as the customer's balance goes.

With Bitcoin there is no master node.  There is no single authority.  

So the double spending risk with Bitcoin has to do with the chance of getting a false positive when accepting a payment transaction that has no confirmations.  With no "master node" available, a merchant checks against the most recent copy of the blockchain to determine that the coins used to spend haven't already been spent.  

That would work, except that a dishonest person can cause the merchant to believe the transaction is valid while at the same time (or later time even) that dishonest party can then broadcast a different transaction that ends up spending the same funds a second time.

The use of 0/unconfirmed allows false positives (i.e., a Bitcoin client might show that funds were received when at a later time a block may arrive with conflicting information) and the initial 0/unconfirmed transaction will disappear as if it had never been made.

Because there's no way to see what is in future blocks then until those future blocks are mined a merchant is exposed to risk of a double spend.

There are various double spend attacks, but to a retail merchant the race attack is the primary one to be concerned with.  A merchant may use a payment processor (such as BitPay) or may go the do-it-yourself (DIY) route.  The client can be configured to protect against being super-vulnerable to the race-attack by not enabling incoming connections and to have outgoing connections be made to well-connected nodes.   There are additional protections that could possibly be built to assist merchants however so few merchants accept on 0/unconfirmed today there hasn't been strong calls for these protections.

For instance, a 0/unconfirmed from someone paying with recently received coins that too haven't yet confirmed is more risky than is a 0/unconfirmed payment from someone who paid using coins that already have had more than six confirmations.  Or another example is a payment made that ends up being low priority due to its size or having no fee paid, etc.   The merchant can tell right away that the transaction will not confirm quickly and might want to delay crediting the payment as the longer the transaction stays unconfirmed the less cost there is to an attacker using rogue mining nodes who will process double spend transactions for a fee.

A bricks and mortar merchant like Cups and Cakes in San Francisco doesn't have much exposure to a double spend attack because it is economically unprofitable.  Let's say a race attack against them succeeds one out of twenty times (probably even a conservative estimate, the more likely rate could be one out of fifty or worse even).  So that means the dishonest customer is visiting 19 times in order to get the 20th cupcake order for "free".  Cups and Cakes probably earns more than 5% profit on each sale, so even with this double-spend exposure they are not losing money due to an occasional double spend.
1443  Economy / Gambling / Re: bitZino - Bitcoin Casino - Blackjack, Roulette, Slots, Craps, Video Poker on: March 24, 2013, 09:03:12 AM
Using a tablet (or worse, mobile) the touch is sensitive -- and oftentimes instead of registering as a click [Edit: I think "touch" is the Andrid equivalent for click] the Android event is interpreted as a scoll operation [Edit: or a drag operation maybe?].

If there were some extenal device which has a single button, "click" for spinning the slots, that would be a useful device.

Does connecting up a gamepad to a tablet (e.g., Nexus 7) enable the ability for someone to bypass the touch and instead treat the button presses as keystroke entries (specifically, whatever is needed for the Spin operation?)

1444  Other / Beginners & Help / Re: MtGox CAD to "Real CAD" on: March 23, 2013, 08:17:15 PM
I've been looking around for a while on the internet, and I couldn't find a place to exchange my MtGox CAD redeem code for "real CAD". The recommended exchange, Aurumxchange, didn't have CAD. Has anybody had similar problems/solutions?

I can't remember if MTG CAD goes away when Coinlab takes over for U.S. and Canadian users of Mt. Gox (or April 10th, technically).  I know issuance of MTG USD is being ended.

Maybe you can find someone to trade them with on #bitcoin-cad IRC.
1445  Economy / Service Announcements / Re: Purchase Gift Cards for Merchants in USA BTC+Dwolla+Lyoness=Gift CARDS on: March 23, 2013, 08:00:22 PM
Comments please good or bad idea?

I've done this transaction (sold bitcoins, withdrew Dwolla and used the funds to buy a gift card through, and it worked fantastically.

The shipping and handling (S&H) for the card(s) is a $5 per order unless purchasing $300 or more of gift cards in which case the S&H is waived.

The order is sent FedEx.

So this is a 1:1 cash-out method.  You send $300 Dwolla USD you get $300 worth of gift cards in the mail.  The only cost in that instance is the $0.25 Dwolla per-transaction fee*.

In the U.S., the Gift Cards (physical cards mailed to you) available are:

 - Chevron
 - Exxon
 - BP (British Petroleum)
 - CVS Pharmacy
 - WalMart
 - Home Depot
 - Lowes
 - Sears
 - Footlocker
 - American Airlines
 - Outback Steakhouse
 - Rotelli Pizza and Pasta

[Edit: New brands include:
 - California Pizza Kitchen
 - Peet's Coffee & Tea
 - Priceline
 - Southwest Airlines Vacations
 - Sears
 - KMart
 - Dollar General
 - Linen's N Things
 - Guitar Center
 - New Balance
 - Golfsmith
 - Zumba fitness
 - Best Buy
 - Straight Talk Wireless (11%!!) ]

Additionally, with Dwolla funds sent to your account you can purchase "mobile gift cards" to certain local merchants.      So even if the merchant has no idea what Bitcoin is, there is a path from Bitcoin to these local merchants.

The reason Lyoness offers this is that it is part of its merchant loyalty program which offers cash-back credited to its members.   So this can actually provide a better than 1:1 cash-out method for Bitcoin since with the "cash back reward" you get more than $1 purchase power when including the cash-back reward received for purchases.

But remember, because this is using Dwolla to fund you can cash out at an exchange that uses Dwolla and this method does not require any withdrawal to a bank account.

Anyone in the U.S. can sign up for Dwolla.  You do not need to link a bank account to Dwolla to use this.

In addition to this being a method to use Dwolla funds to buy gift cards to national brands or to fund mobile gift cards to other merchants, there are cash-back benefits available at other merchants as well if you happen to be interested as well.  

Full disclosure, forum user EndTheFed321 gets a residual commission for all subsequent purchases made through by any members who are signed up by him.   That same ability to earn residuals is available to anyone else as well.

* If you don't already have a Dwolla account, you can sign up (referral link) and get a credit towards $10 of your Dwolla fees.
1446  Bitcoin / Meetups / Re: SoCAL BITCOINERS Poll: Where to meet??? on: March 23, 2013, 07:36:12 PM
Josephine's is now offering free wireless internet access to its patrons

I'm bringing a Wi-Fi enabled tablet too.  Then bitZino slots or something to let the server try to juice up the tip a little.

Looks like there will be a few attending:

5  [so far]

I have reserved a table under Jose
1447  Bitcoin / Meetups / Re: SoCAL BITCOINERS Poll: Where to meet??? on: March 23, 2013, 10:23:39 AM
There will be at least two Bitcoiners meeting (myself being one of them) in Cerritos this afternoon (Saturday March 23, 2013).

Details for the afternoon event:

a meetup for Saturday March 23

place 11305 183 Street
90703 Cerritos

time 3:00 pm

[Update: There had been the desire expressed for an evening event as well. Notice was too short to try to plan one for today (Saturday March 23) but suggestions for an April date and location might help cause that to happen.  A location with Wi-Fi would be preferred.
1448  Economy / Currency exchange / Re: Selling 1. Bitcoin for Dwolla on: March 23, 2013, 03:31:18 AM
At Mt.Gox latest price you send first. to My Dwolla and I will send

I'm out of Dwolla at the moment or I'ld offer to help.  Don't forget Camp BX is a good BTC -> Dwolla method, if you can wait the X number of hours for them to process withdrawals.
1449  Economy / Service Announcements / Re: Hotel in Belize Accepting Bitcoin on: March 23, 2013, 02:26:41 AM
The owner of Pedro's Peter Lawrence saw the potential benefits that Bitcoin could bring to his business. Lawrence said, "With Bitcoin we will be able to lower our transaction costs. It's perfectly suited to our type of business where nearly all of our reservations are taken online or over the phone."

Yes, travel is one of the "high risk" merchant account categories in which they aren't paying 3% rates, but instead much higher .. 6% and up even.  So this makes perfect sense!  Additionally, now Pedro's is one of the first to offer it so they'll get additional publicity (and likely revenues) just for being a bricks & mortar merchant that accepts bitcoins.
High Risk Merchant Accounts
1450  Economy / Gambling / Re: [BITLOTTO] Mar 1 draw over $2000 or 50BTC! Tickets now 0.1 BTC for Apr 5 on: March 22, 2013, 07:57:39 PM
I expect this is all fake (it would be if I owned the site)

Ya, operating a direct competitor to a State-run lottery would be something you would pretty much need to do anonymously.

There were concerns right off the bat, of course:

Or running away with.  Cool Wink

Ok. I admit that made me laugh. Seriously though, I'd be nuts to run with the money, I'd be better off making a small share honestly over a long period. Sure 246 BTC would be nice but I'd rather run a successful lottery in the future. I intend on running this for a very long time and with time people will see I'm doing exactly as I said.

And the use of an escrow was discussed here:

Lottery guy bets entire BTC fortune and ... loses? Smiley

And there was the claim of having a partner, to keep the bus factor at two (i.e., if bitlotto operator gets hit by a bus someone else has the keys.)  Of course, there is no confirmation this exists, but if this delay is due to challenging circumstances there was supposed to be a backup to deliver the winnings. Being March 22nd and neither the normal payout nor the backup alternate having occurred has things looking worse though.
1451  Bitcoin / Bitcoin Discussion / Re: FinCEN addresses Bitcoin on: March 22, 2013, 06:30:04 PM
Excerpt from prepared remarks of

Jennifer Shasky Calvery,
Those who are intermediaries in the transfer of virtual currencies from one person to another person, or to another location, are money transmitters that must register with FinCEN as MSBs unless an exception applies.

It sounds like they're interested specifically in exchanges.

I just re-read that and am now seeing that part being missed in the various initial interpretations of FinCEN's guidance.   FinCEN's guidance only addressed transfer of virtual currency when "as part of the acceptance and transfer of currency, funds, or other value that substitutes for currency".  

But how would an EWallet provider know if I was sending from my EWallet to someone as part of a transfer of currency or if it was a gift, or perhaps I bought something and was paying with bitcoins.

From the director's remarks, it sounds like an EWallet would be an MSB (and thus need to obtain identity of the users then).   But almost no EWallets require that.     And I don't need an intermediary to transfer bitcoins anyway -- I can send right from my own client, without using an EWallet.

Or, are all peer nodes now considered "money transmitters" that must register with FinCEN as MSBs.

This isn't guidance from FinCEN, this is mis-guidance from the highest level.
1452  Economy / Gambling / Re: [BITLOTTO] Mar 1 draw over $2000 or 50BTC! Tickets now 0.1 BTC for Apr 5 on: March 22, 2013, 10:03:15 AM
Does anyone know him in real life?

There is an address and phone number in the whois for the domain.  I've not called it or texted to it, but that is an option.

Incidentally the domain is set to expire in a couple weeks.  It is hosted with Kalyhost, which means to probably get started on renewing that ASAP so that it has renewed before expiry.
1453  Local / India / Re: How Do We Serve India, 1/5th of the Global Population, with Bitcoin? on: March 22, 2013, 08:57:35 AM
I would like to add funds to my account at Milap.

I can add funds by redeeming a gift certificate.  

The gift certificate can be purchased by anybody, using INR either through Indian credit card or through Netbanking:
 -  <-- Click Contribute, then enter your name, e-mail, city and country.  
Then choose Currency INR and enter N,NNNN Rs. enter "Water" for Cause.

I'm looking for a 1,500rs gift certificate. 

Is anyone looking to convert their debit card (INR), credit card (INR) or NetTransfer (INR) for Bitcoins?   If so, PM me please.
1454  Bitcoin / Press / Re: 2013-03-21 'Segment 4 -- Cloudy Cash' on: March 22, 2013, 06:45:51 AM
Host Brian Lehrer and guests Erik Voorhees (@ErikFoorhees) and Marc Hochstein (@MarchHochstein)  

(The video shows a typo on Erik's name and Twitter handle.)

Taped: 3-18-13

Segment 4 -- Cloudy Cash

Finally, Bitcoin, and what the rise of the controversial cyber currency means for banks, government and the economy with guests, Marc Hochstein and Erik Voorhees. Hochstein is executive editor of American Banker magazine and Voorhees directs marketing and communications at, a New York-based Bitcoin payment processor.

I liked the question about how Bitcoin will be used 10 years out if it succeeds.  Erik responded that those financial intermediaries who profit from "moving" bits will be displaced.
1455  Economy / Economics / Re: Bitcoin Economy Value --> $519,555,304.09 on: March 21, 2013, 10:47:41 PM
"Total" implies adding all the values which is clearly not what's being done.

That is exactly what is being done.   If a bitcoin trades at $65 then the total dollar valuation (TDV) is the sum total of each bitcoin that exists at the trade value of $65.

Or am I misinterpreting your comment?
1456  Other / Beginners & Help / Re: Shorting Bitcoins? on: March 21, 2013, 10:40:30 PM
Also, CampBX can execute advanced trades and margin.

Not today.  Their site has had that teaser since it launched more than a year and a half ago, but they currently do not have the margin trading, stop loss feature, etc.  Because they do accept deposits of USD funds through Dwolla there is one technique that some use to gain leverage for trading bitcoins.  Dwolla Instant is a method in which Dwolla provides a loan of up to $500:

While hopefully this access to credit isn't being used to speculate by those who would not be able to afford the losses should the exchange rate move unfavorably for that speculator, it does become a tool allowing a trader to short in an alternate way. 

There is demand for "dollar loans" in which bitcoins are the transactional currency but the loan agreement specifies payment of interest and the return of principal to be calculated in terms of dollars.  So by taking a USD loan through Dwolla Instant, buying bitcoins with those borrowed funds and then lending them out to a borrower at a higher interest rate then that person is in effect shorting bitcoins using leverage.  If the speculator is correct and the exchange rate drops by the time repayment of the loan occurs, there will be a net positive balance of bitcoins after settling (repayment) of the Dwolla USD loan.    Of course, there is risk of default by the borrower so this method of shorting should only be considered by those with experience in lending.

1457  Economy / Speculation / Re: The Weekend Dip Myth on: March 21, 2013, 09:54:23 PM
Time cycles come and go, and if they are correct too often, this is typically the time when it does not work any more.

I still believe that in a downtrend the weekend dip strategy can still be profitable, but we haven't seen any decent downtrends in many months.  This last one resulted essentially in a wash unless perfect timing allowed a tiny profit.

Needless to say, this weekend we are not in a downtrend (specifically we are up more than 40% week-to-week), so there's no green light.
1458  Economy / Trading Discussion / Re: Current Leveraged Bitcoin Trading Options on: March 21, 2013, 12:56:48 PM
Anything else?

CALL and PUT options on MPEX.

Kraken is supposedly nearing as well.

1459  Bitcoin / Bitcoin Discussion / Re: March 2013 Chain Fork Post-Mortem [Draft] on: March 21, 2013, 12:47:54 PM
For resolving the double spending, I wonder if there's another approach for recovering after an accidental hard fork.

I could see providing at startup a block hash which is the block at the end of the forked chain.  Transactions from all those blocks (down to where the fork started) get added to the mem pool and nothing else until those transactions are either invalid or included in blocks. Additionally, the node broadcasts the transactions as well to peers. 

Other blocks would still be accepted like normal, so there is still a risk of a double spend from a successful race attack, but since any transactions in the fork would be re-broadcast as well as be given priority for inclusion the chances of success by the person trying to get away with a race attack double spend decrease significantly.
1460  Bitcoin / Bitcoin Discussion / March 2013 Chain Fork Post-Mortem [Draft] on: March 21, 2013, 12:34:10 PM
I see on the wiki is BIP 0050.

March 2013 Chain Fork Post-Mortem [Draft]
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