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141  Other / Beginners & Help / Re: Do you think another 51% attack will happen? on: January 26, 2014, 01:43:08 PM
I worry that a 51% attack on Bitcoin is inevitable. It is frightening to think that an organization could buy up enough mining equipment to fork the blockchain.

Right now let's say that KNCMiner had ample supply of their KNC Neptunes -- one of the best rigs as far as cost/hash.  This is a hypothetical because KNC has sold out on what they accepted so far for pre-orders for future shipments.  But let's say you could place a large order and get it shipped overnight (or at least, before difficulty jumps again where you need to order more).

Total network capacity (currently, using 16,116 Th/s (SHA-256).
KNC Neptune performance: 3 Th/s.
KNC Neptune cost; $10K

So you would need 5,372 of those bad boys to get 51%.  That's a $54 million investment in hardware.

Now let's say you had that capacity online today -- mining secretly on your private fork of the blockchain.

What capabilities do you have?

You can send bitcoins to an exchange(s), and then on your private fork of the blockchain you can spend those same bitcoins elsewhere (to another address you control, for instance).   But to gain any value you need to take delivery of something of value in a non-reversible manner so that after you broadcast blocks from your private fork the exchange(s) you cheated have no recourse.

How are you going to get $54 million worth of value from an exchange(s)?   Withdraw Bitcoins?  Most exchanges emply hot wallets with a limited balance (with the remaining coins held in cold storage) -- there's no way tens of millions of dollars worth of non-reversible funds will be available for withdrawal immediately.  Even if there was, they wouldn't be available for withdrawal anonymously.

So there's really no economic incentive for performing a 51% attack for the purpose of double-spending against Bitcoin.

That doesn't mean it won't or can't happen, it just means the likelihood of it occurring is pretty small.

Now take a Dogecoin.  
Total network capacity (currently, using BitInfoCharts ): 84 Mh/s (Scrypt).
"beefy" GPU performance: 0.75 Kh/s.
"beefy" GPU cost: $450 + $75 (1/3rd of a rig, assuming 3 GPUs per mobo+power/supply rig)

So you would need 112,000 of those bad boys to get 51%.  That's a $59 million investment in hardware.    

But ..., here we have some very immature pools (in terms of infrastructure spending and experience) with a good chunk of the hashing capacity (scroll to bottom to see pie chart):

So you DDoS DogeHouse, Multipool and Fast-Pool, and now you only need maybe 40 Mh/s to be able to make your private Dogecoin blockchain fork to be the longest.  I don't know if there still are many cheap GPUs available yet but at one time you could have bought or leased a ton of GPUs -- meaning acquiring 50,000 of them was possible.

But even this approach, with a $20M investment in hardware is not going to be a profitable attack, as you aren't going to extract $20M of value from Dogecoin through exchanges.  

So today, Dogecoin (and Litecoin) appear to have a sufficient level of mining capacity as long as no attacker has invented and produced a Scrypt-based ASIC miner.

But let's say someone put in $4M of capital and has today 40 Mh/s of hashing capacity from the first week or two of production of the scrypt-based ASIC that party has produced.   Can that party extract $4M of value from alt exchanges that support Dogecoin?  Are there enough of these exchanges allowing anonymous accounts (or did poor enough KYC where a number of fake accounts exist?).   If so, then it is entirely plausible that a 51% attack against Dogecoin (or Litecoin even) could be performed successfully, and done so at a profit.

Worse, depending on the jurisdiction that those exchanges operate, the pain could be felt even by those who didn't touch a Doegecoin or Litecoin even.  

This is because in many jurisdictions, funds sent for deposit at a crypto-currency exchange are treated as liabilities owed by the exchange.   It doesn't matter if the attack was against Dogecoin, if the exchange goes bankrupt (unable to honor all withdrawal requests) all accountholders are in the same boat.   Your bitcoins at a Cryptsy are no safer than your Litecoins ... if Litecoin is successfully attacked.

So Bitcoiners who use alt-coin exchanges should be cautious with their funds left there.     Kraken is the only exchange that has published their policy plans on what would happen should an altcoin be attacked successfully with a 51% attack (or other failure that results in losses of customer's funds):
142  Alternate cryptocurrencies / Altcoin Discussion / Re: Exchange with USD to 7 Alt Coins on: January 26, 2014, 09:34:06 AM

What is the reason behind the 30 days waiting period before I can withdraw my bitcoin?  That is a long time to wait.  I might as well sell it and withdraw the cash.  


Edit:  How come I didn't have to wait for LTC withdrawal?

Is this restriction still in place?   If so, that would make me more comfortable using CoinMkt for my trading.

I have a concern about having my bitcoins sit at an exchange (while waiting for an opportunity to sell, such as a potential to profit from arbitrage) but am afraid that with an exchange that also deals with alt-coins that I am at risk should the exchange suffer losses due to a successful 51% attack against an alt-coin.  This concern exists even if I don't touch any alt-coins because in most jurisdictions, once I deposit my bitcoins with the exchange, I have a liability from the exchange that is no different from anyone else's liability.   Specifically, if the exchange suffers losses from a hack attack, 51% attack or any other reason, I would not be guaranteed I could get my bitcoins back.  I shared this concern in a blog post:

When Mt. Gox announced that they were coming out with Litecoin trading, I asked some questions:

But never got an answer other than a response that my "concerns will be considered".

When Kraken announced tat they were supporting alt-currencies, I asked a similar set of questions and got straight answers:

So I would like to describe four specific scenarios that I would like to know what CoinMkt's policy is should they occur:

A.) My CoinMkt exchange account holds only fiat and bitcoins, and I've never traded for altcoins.  Would I be exposed to any risk of loss to those funds should there be a successful 51% attack against an altcoin that CoinMkt supports?

B.) I have a balance of an altcoin and fiat, but had none of those altcoins deposited to CoinMkt in any block that was ultimately orphaned as the result of the 51% attack.  Would I be exposed to any risk of loss to those funds should there be a successful 51% attack against that altcoin?

C.) I had bitcoins at CoinMkt and I traded them for an altcoin.  Following this trade the attacker released blocks that resulted in a double spend such that the that altcoins I received were from the attacker's account (i.e., an altcoin deposited with a transaction that no longer confirms or was double spent).  Following the successful 51% attack against the altcoin, do I still have my altcoins that I purchased that I can withdraw (or trade back into Bitcoins)?

D.) In my CoinMkt account I had deposited an altcoin from a block that utimately was orphaned as the result of a successful 51% attack against the altcoin.   Before the attack I was able to trade those altcoins for bitcoins which remain in my account.    After the successful 51% attack against the altcoin, do I still have the ability to withdraw those bitcoins?

143  Bitcoin / Bitcoin Discussion / Re: Bitcoin-themed banner to be waved during Super Bowl XLVIII in MetLife Stadium. on: January 23, 2014, 11:39:01 PM
  • Watch and record the Super Bowl to see the banner in motion.

Would have changed the odds on this:

Bet: Bitcoin will be mentioned or pictured during the 2014 SuperBowl

144  Economy / Services / Re: Looking for inexpensive colocation in Los Angeles on: January 22, 2014, 12:20:34 PM
Looking forward to serving you.

And the big remaining question is ...     Bitcoin accepted?
145  Bitcoin / Project Development / Re: ICBIT Derivatives Market (USD/BTC futures trading) - LIVE on: January 09, 2014, 07:11:32 AM
There was a problem with DNS information, so that API server was resolving to wrong IP address in some cases. This was fixed shortly, sorry for inconvenience.

Some issue is occurring again.  If there is a maintenance outage, there should be some message displayed on the site.  And there should be some communication of status out-of-band, ... perhaps here on this thread, or/and on the @ICBIT_se Twitter account maybe?
146  Economy / Marketplace / Re: NEFT Vodka and Bitcoin on: January 06, 2014, 05:49:45 AM
Any online distributors in the US yet? I want a barrel!

Since it is now sold within the U.S., it should be easy to find someone from L.A. or Vegas who would be able to buy one and ship it f to you.  You could probably even post the gig on or TaskRabbit or something like that.    Maybe even on
147  Bitcoin / Bitcoin Discussion / Re: Reggie Middleton builds Zero Trust Digital Currency Contracts on Blockchain on: January 06, 2014, 05:43:20 AM
given his track record of publishing financial info early and sometimes against the crowd (FB, Ireland, Apple, Google etc) this deserves a chance.

Yes -- Reggie does his homework.  I'm thrilled to see him see Bitcoin's potential, and possibly take Bitcoin further in ways other's haven't yet done.
148  Bitcoin / Meetups / Re: Los Angeles (SoCal) Bitcoiners Meetup? on: January 05, 2014, 10:11:08 AM
While this entry here is unrelated to any meetup, it is related to Bitcoiners in Los Angeles / SoCal:

NEFT Vodka (the brand with the Bitcoin logo on the "bottle") is now available in the U.S. -- but only in Los Angeles (for now, ... later available in Las Vegas as well):

Here's a post describing locations in L.A. where it is available for sale:
149  Local / Marketplace (India) / Re: WTB: gift certificate (INR) on: January 05, 2014, 09:42:53 AM
I'm looking to add 3,000 Rs again.  

I forgot to update this earlier -- I have completed this transaction successfully.

Will probably be looking to do this about once a month so will update here the next time I'm looking for more rupees.
150  Bitcoin / Meetups / Re: CES 2014 - Consumer Electronics Show - January 7-11 - Las Vegas on: January 05, 2014, 09:26:56 AM
Can't see their being many bitcoin-related booths there ....

What they lack in quantity they'll have in quality.

Sunday evening (Jan 5th) is @StartupDebut at Bali Hai:

There will be a Bitcoin Pavilion there.

@LamassuBTC will have an ATM there and it will be operational (for the Startup Debut event)
@KryptoKit which was featured with the Zynga tokens story will be features
Members of @BitAngelsdotCo will be present
I believe there will be others attending as well.
151  Bitcoin / Meetups / Re: CES 2014 - Consumer Electronics Show - January 7-11 - Las Vegas on: January 05, 2014, 09:14:37 AM
If anyone is attending CES from out-of-state, they might be interested in this:

NEFT Vodka (the brand that has a Bitcoin logo on the "bottle") is available in the U.S. exclusively in just two places, Las Vegas and Los Angeles.

From another thread:
And this guy sells everywhere in LV - You can contact  him directly. When buying in Bitcoin you get 10% discount!

Stefan Manchev
VP International Affairs
Rebel Wine & Spirits
4132 S. Rainbow BLVD. #150
Las Vegas, NV 89103
Direct: 702.420.0284
152  Economy / Marketplace / Re: NEFT Vodka and Bitcoin on: January 05, 2014, 09:08:46 AM
In LA, Jons Market  - 6 Locations:

If that was to say at all Jons International Market locations, there are many Jons International Market locations in L.A.:

  • House of Liquor
  • Anush Bakery
  • Remedy Liquor
  • Joe’s Liquor
  • Eden Wine & Spirits
  • Super Meat & Liquor

House of Liquor - Glendale
1008 E Colorado St
Glendale, CA 91205
(818) 242-3054

Anush Bakery - North Hollywood
6770 Coldwater Canyon Avenue
North Hollywood, CA 91606
(818) 759-4747

Remedy Liquor - Glendale
1700 W Glenoaks Blvd.,
Glendale, CA 91201
(818) 549-1055

Remedy Liquor - La Cañada Flintridge
823 Foothill Blvd.
La Cañada Flintridge, CA 91011
(818) 790-007

Joe's Liquor
[There is more than one listing for a "Joe's Liquor" in L.A., so I'm not sure if they all carry NEFT.  I'll list multiple addresses here:

Joe's Liquor (1 of 2)
12521 Victory Blvd
North Hollywood, CA 91606
(818) 762-5757

Joe's Liquor (2 of 2)
16151 Nordhoff St
Los Angeles, CA 91343
(818) 894-2001

Eden Wine & Spirits - Glendale
333 N Verdugo Rd
Glendale, CA 91206
(818) 502-5020

Kozanyan Meat & Liquor - Glendale
(Jan's list showed "Super Meat & Liquor", but that listing appears to be under a new name now)
1244 S Glendale Ave
Glendale, CA 91205
(818) 242-6474

And here is the bomb:
In one month I will stop selling Neft for fiat to anyone - only for BTC.

Ha!  Bitcoin exclusivity!  That's one way of helping Bitcoin to gain traction!
153  Bitcoin / Meetups / Re: Los Angeles (SoCal) Bitcoiners Meetup? on: January 02, 2014, 06:27:11 PM
The next LA Bitcoin meetup:

Bitcoin Discussion and Q&A with Andreas M. Antonopoulos
Thursday, January 9, 2014, 7:00 pm
Amplify - 1600 Main St., Venice, CA

154  Economy / Marketplace / Re: NEFT Vodka and Bitcoin on: January 02, 2014, 03:42:42 PM
Anyone know, is it possible to get this in the USA?

Good news!  

I've been informed that NEFT is now "available in California" and that they are "looking to begin in Las Vegas" this month.

These do have the Bitcoin logo on the barrel (as they were on the ones at the Bitcoin Conference in San Jose).

I didn't get the name(s) of merchants selling NEFT, ... but I believe BevMo was supposed to be one.

I'll solicit help from some SoCal Bitconers to learn where NEFT can be purchased, but if anyone following this thread already knows, please share!

155  Bitcoin / Bitcoin Discussion / Re: NSA can rob peoples BTC wallet in new devices such as the iphone on: December 31, 2013, 11:56:00 AM
While I don't spend my time sweating the NSA,

Yes, I'm comfortable with the opinion that the NSA isn't trying to steal people's bitcoins.

I'm more worried about the rogue sysadmin at a mobile carrier that has access to sneak in a few lines of code into an official update, unbeknownst to all until the bitcoins are swiped.  Discussed here:

Can a mobile be protected against the “Linode problem”?

156  Economy / Service Discussion / Re: Whatever happened with Bitcoin Wireless? on: December 30, 2013, 12:11:54 PM seems frozen in time.

Worse, ... looks aborted as it now has that backpack girl.

I remember hearing from Charlie Shrem at the Atlanta bitcoin conference in October that they were moving forward with that.

Maybe plans changed.  Or maybe it will be a different brand?
157  Local / Marketplace (India) / Re: WTB: gift certificate (INR) on: December 30, 2013, 11:23:56 AM
I would like to add funds (rupees / INR) to my account at Milaap, which is like a Kiva in India (though these are all no-interest loans).

I'm looking to add 3,000 Rs again.  

How this works is,
1.) You and I agree on the rate (in BTC) for your 3,000 Rs.  [e.g., ~0.067 BTC if using today's BTC/USD of $730 on BitStamp]
2.) I provide to you my e-mail address.
3.) You buy a 3,000 Rs gift e-card from Milaap, paying with your Netbanking or with an Indian credit card.  Entering my e-mail as the gift recipient.

 -  <-- PM me for my Milaap "lender name and e-mail".

4.) You send to me your Bitcoin address for my payment
5.) I receive the e-mail, redeem the gift e-card, and send to you the bitcoins.

PM me if interested
158  Bitcoin / Bitcoin Discussion / Re: Getting around a government ban on BTC on: December 19, 2013, 09:58:38 AM
That's what '' does.

I'm guessing that the fun will come to an end if/when it becomes unlawful to deposit cash into a random person's account without some modicum of 'know-your-whatever-ness'.  I'm surprised it's even allowed now to be honest.  Probably it would be implemented by some combination of claw-backs and/or banks just shutting out customers who do this.  My guess.

I forgot about that ... sure, if cash deposit in China works, then or similar service there would work pretty well.    That is .., until they start confiscating funds of people caught selling coins that way.

I wonder if cash deposit (by a third party, without providing identity) is an accepted method in China.
159  Bitcoin / Bitcoin Discussion / Re: Getting around a government ban on BTC on: December 18, 2013, 07:49:33 PM
What would an exchange look like that is able to get around this?

Any decentralized approach taking advantage of a payment network with A2A (Account-To-Account) transfers will work.  


It's easy for China to crack down on one or two large exchanges which integrate with the banking system.

It's a lot harder for them to crack down on individuals using Alipay or similar.  

That's why many, many individuals today still trade bitcoins for Dwolla -- even with Dwolla saying they don't allow any Bitcoin trading.  You won't find the advertisements from those who do it, but the trades happen.  Daily.   Same for PayPal, etc.

160  Bitcoin / Legal / Re: List of court cases, complaints, regulatory actions, etc. on: November 20, 2013, 07:41:54 AM
Location: Newark, New Jersey
November 19, 2013

Abstract: The Attorney General for the state of New Jersey sued E-Sports Entertainment whose software was updated mine bitcoins on its customers computers.

 - (Judgement viewed in browser-friendly PDF viewer)

The AG’s office says that company co-founder Eric Thunberg and software engineer Sean Hunczak were both involved in the scam. In a statement posted to its website, ESEA said the software was the work of a single engineer, presumably Hunczak


Previously a class action suit had been filed:
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