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8741  Bitcoin / Legal / Re: Loss of Profits, Libel, Team Ponzi and a Pirate on: August 17, 2012, 10:07:28 PM
Not even close.  First of all to prove liable/slander (at least in the US) the person making the statement has to KNOWINGLY make a false statement.  The mere fact that the statement is false is not sufficient.  So if someone posted some faked screenshots/records/scanned docs showing Pirate selling the deposited coins and transferring money to a bank account in the cayman islands AND it turned out to be false AND you could prove the person posting it knew it was false (faked it himself) AND that statement caused a loss AND you could prove the loss was directly related to the false statement (coincidence is not correlation under the law either) AND you suffered a loss you would have a case.

Even then it would be very hard to prove and win and the damages likely would be far beyond anything the defendant could be paid so almost certainly the judge would reduce them.

Another way to look at it is IF you run a business that is 100% legit but it utterly indistinguishable from a ponzi scheme then guess what .... the risk that it will be confused with a ponzi scheme and you may suffer a lack of liquidity as a result is a business risk.  A risk that both the operator of the business and the investors should have considered.   Lets assume Pirate operation was 100% legit.  Could he have done anything to mitigate that risk?  Transparency?  Delayed withdrawals?  Working with a smaller pool of high net worth investors?  Since he chose NOT to take steps to mitigate that risk factor and the "investors" decided to ignore that risk factor any losses are solely the fault of the operator and investors.
8742  Bitcoin / Bitcoin Discussion / Re: The reality of BTC that too many (and myself) dont want to believe. on: August 17, 2012, 09:00:21 PM
Those who don't want wallets, apps and so forth can just use bitcoin debit cards and such.

It's as complicated or as simple as people want to make it.

Exactly.  Bitcoin is a platform.  GernMiester obviously never played with creative toys as a kid.  It is like saying nobody will ever use the internet.  Do you know how hard it is to manually create TCP/IP packets. 
8743  Bitcoin / Pools / Re: Pay per share rate before fee or after?? on: August 17, 2012, 03:47:42 PM
I guess that makes it ppnos.  Pay per not orphaned shared.

8744  Bitcoin / Development & Technical Discussion / Re: Mining, a flawed concept coming home to roost? on: August 17, 2012, 03:43:51 PM
Sure but that substantially increases the cost.  True cost is much higher than $1M per TH/s when you consider infrastructure, labor, security, insurance, electricity, etc.  Lets say $2M per TH/s. A 90% attack today would cost ~$200M take almost 20 days to hash a re-org that deep (plus setup time) and the attacker risks ASIC being released skyrocketing the "good difficulty" in the meantime.  A massive amount of money to risk for the tiny economy that is Bitcoin.  

In the future when attacking Bitcoin may be worth $100M it couldn't be done with $100M it would require billions. It creates an interesting risk vs reward dynamic.   The cost rises as Bitcoin gets larger but it may not get larger so spending a huge sum now to avoid an even larger sum in the future may be a poor bet.  A bet that costs millions.  
8745  Bitcoin / Development & Technical Discussion / Re: Should bitcoin lower the transaction fee? on: August 17, 2012, 02:39:32 PM
Before I left for vacation, I submitted a pull request that makes the default policy for miners "more fees == more likely to get into a block."  That will be in the 0.7 release (the policy before was mostly "higher priority == more likely to get into a block"), and I've been encouraging the big mining pool operators to implement something similar if they have their own transaction-selection code.

When I get back from vacation I plan on writing code to watch the transactions that do or do not make it into blocks to derive an estimate of the average miners' fee policy, and use that to recommend a reasonable fee to the user.

Those changes will let fees float naturally-- users and miners will form a market and fees will rise or fall based on what users are willing to pay and what miners are willing to accept. I don't like the arbitrary, centralized setting of fees that we've had up until now.


Nice.  I am pretty sure at least some pools prioritize based on fee using custom code.  In analyzing DeepBit blocks I am fairly certain they are doing some prioritization other than pure priority.  It will be good to have it in the reference client though.  That gives all miners and pools the ability to do similar prioritization without a lot of reinventing the wheel.

However correct me if I am wrong even if when your pull is integrated in future versions the mandatory fee on low priority tx will remain.  Right?  It exist to prevent denial of service or spam attacks.  A fee market place won't negate that (at least not for a while). 
8746  Bitcoin / Development & Technical Discussion / Re: Should bitcoin lower the transaction fee? on: August 17, 2012, 02:35:40 PM
I use blockchain.info/MyWallet to send amounts down to just BTC1.00 that I have often only just received so have to pay the recommended "default" BTC0.0005 like satoshi dice.  So once btc/usd>$100 that's $0.05 on even a $1 transaction or 5% fee.  I understand the need to stop blockchain spam but wouldn't having the lowest fees possible help the adoption of bitcoin by people transacting sub $1.00 amounts often as btc value rises.  

Last time before I give up forever.  As I pointed out the mandatory fee (which isn't required on all tx just low priority ones) was lowered to the current 0.0005 when BTC was $20.  Considering lowering it to 0.0001 when BTC is sustainably >$100 probably makes sense.  That keeps the fee below 1 US cent.

However the point you seem to be missing (over and over and over across multiple threads) is that the mandatory fee doesn't determine the actual fee.  

1) Mandatory fee is only required on low priority transactions.  Simply wait long enough and you could pay 0 BTC on your $1USD equivelent tx.  Tada.  The mandatory fee being 0.0005 or 0.0001 doesn't really matter if you don't pay it.

2) Users are paying fees HIGHER than the mandatory fee.  Gavin change suggested above will only accelerate that.  Transaction volume increasing will only accelerate that.  There is finite space in a block and tx processing does require some amount of real cost.  It is entirely possible the mandatory fee could be cut to a single satoshi or removed completely and you STILL would have to pay a much larger fee simply due to competition (or wait days or weeks for your free tx to finally get processed).
8747  Bitcoin / Development & Technical Discussion / Re: Mining, a flawed concept coming home to roost? on: August 17, 2012, 02:14:51 PM
Well they certainly couldn't start today and cause a re-org that deep with only 51% control.  Sure they could have started 6 months ago but that means the 51% attack occurred 6 months ago not today.  Still that wasn't Blinken's understanding or post.  He seemed to indicate miners "vote" on tx and can choose to alter them.  Taking a tx from A->B and making it A->C where the attacker does not control the private key for A. 

TL/DR:
"If you can verify, you can do whatever you want. " is a 100% false statement.

Still if are really worried about a 25,000 block re-org then don't accept coins unless the unspent output is prior to the last checkpoint.  Speaking of that what is the last checkpoint. Smiley
8748  Bitcoin / Bitcoin Discussion / Re: Bitcoin vs Fiat - isn't this a bit of a double standard? on: August 17, 2012, 02:08:43 PM
What is gold backed by?

Backing is a simplistic concept.  The United States dollar is backed by the economic and military power of the United States.  How effective of a backing that is doesn't really matter is it backed by something.  Likewise Bitcoin is "backed" by something.  It gains value from the utility created by the network (secure, fast, decentralized transactions).  Is that "backing" worth $14? Well the market is saying right now it is.   Maybe you think it is worth more or less but it is backed by something.  If you think that isn't true I would gladly sell you 28 quadrillion D&T coins for a mere couple thousand of your Bitcoins.  Since they are both backed by nothing obviously that is an amazing deal.


The difference between fiat and bitcoin has absolutely nothing to do with a simplistic concept of "backing". Fiat means BY DECREE.  The government issues money BY DECREE.  Money you have absolutely no control over.  You may get a promotion and 20% pay raise this year only to have the government over issue currency such that your "higher" pay actually means you are poorer in real time (adjusted for inflation).  If the FED prints an extra $1 trillion what can you do about it?  Nothing.  The currency is issued by DECREE.  The govt mandates it existance and you suffer any ills from that centralized control. 

What makes Bitcoin different than fiat is ... it isn't fiat.  It isn't issued by decree.  You can't force anyone to accept Bitcoin.  If they do it is by choice.  Nobody control Bitcoin.  Nobody can choose to alter the rate of inflation (to their benefit and the detriment of others).

Note I sidestepped the entire argument of which is better, just pointing out bitcoin IS different than fiat currencies and the reason has nothing to do with "backing".
8749  Bitcoin / Development & Technical Discussion / Re: Should bitcoin lower the transaction fee? on: August 17, 2012, 04:04:20 AM
Transaction fees will be very important towards miners fee's in the future.

Once again.  The mandatory fee will likely be completely irrelevant in the future.  It isn't designed for revenue.  Never was, never will be.  Competition will cause users to pay a much much higher fee for fast processing than the mandatory fee (which is only designed to mark denial of service attacks prohibitively expensive).

Case in point even now satoshi dice pays a tx fee roughly 5x higher than the mandatory fee and they pay it on tx which don't even require the mandatory fee.  In the future it won't matter much if the mandatory fee is 0.0005 btc but your client advised you that to have a good chance of being include in the next 20 blocks will require a fee of 10x that. 
8750  Bitcoin / Development & Technical Discussion / Re: Password Hashing and Storage on: August 17, 2012, 03:52:51 AM
To anyone clinging to outdated ideas like using SHA-1 (or SHA-256/512, RIPEMD-160, etc) for storing passwords a simple question to ask yourself.  
Does your login server need to be able to process 4 billion logins per second?  No?  
Then why are you using a algorithm which allows the hacker to brute force at the rate of 4 billion attacks per second?  

Use an algorithm like bcrypt and pick a workload so that your login throughput is only say 20 logins per second (@ 10% cpu load).   That means the average CPU based attacker can attempt couple hundred attacks per second, and the average GPU a mere couple thousand attacker per second.  

Bcrypt is no better at "being slow" than SHA-based password hashing schemes. When you increase bcrypt's difficulty factor, you're just increasing the number of times a hash-like algorithm is applied to the data. It's exactly the same as increasing the number of rounds in SHA256-crypt. I prefer SHA2-based schemes because SHA-2 was specifically designed for things like password hashing, and its use is recommended by many standards.

There is nothing wrong with using PBKDF2 (a solid multi-round algorithm which can use SHA-256 among other hashes).  However most users attempting to roll their own multi-round SHA function will likely create vulnerabilities.  First they will under estimate how fast SHA-256 is.  100 rounds or even 1,000 rounds is worthless.  For brute force resistance one needs hundreds of thousands of rounds.  Second they likely will introduce vulnerabilities like creating intra-round collisions.    They may underestimate the need for salt or the size of the salt.  They may try to do things like derive the salt from low entropy sources, etc.  The advantages of PBKDF2, bcrypt, and scrypt is they are end to end solutions.   password in -> solid multi-round cryptography -> hash out.

PBKDF2 (using SHA-256) is well tested and a good alternative to bcrypt, but bcrypt has an advantage of limiting attacker's hardware advantage.   Even a single round of bcrypt (blowfish) is roughly 1,000x slower than a single SHA-256 hash and bcrypt doesn't optimize well on GPUs.  The average GPU is in the ballpark of ~100x as fast as the average CPU when it comes to SHA-256 hashing but only ~5x as fast with bcrypt.  Since most servers are using CPU picking an algorithm which is optimized for GPU doesn't aid the server any but it certainly does aid the attacker. bcrypt creates a more level playing field and that hurts the attacker.

That being said nothing wrong with PBKDF2 as an alternative to bcrypt. My post was more about single round SHA-256.
8751  Bitcoin / Development & Technical Discussion / Re: Password Hashing and Storage on: August 17, 2012, 03:26:31 AM
To anyone clinging to outdated ideas like using SHA-1 (or SHA-256/512, RIPEMD-160, etc) for storing passwords a simple question to ask yourself.  
Does your login server need to be able to process 4 billion logins per second?  No?  
Then why are you using a algorithm which allows the hacker to brute force at the rate of 4 billion attacks per second?  

Actually I don't think that the algorithm is so important as limiting the # of attempts to login to the same account (as is done by banks) - it would be a pretty stupid piece of software that actually allows even 100 attempts to login to the same account within minutes.


Brute force attacks are done against the db.  No server side code is going to stop that.  Honestly password878 is likely strong enough against an attacker trying to login as you.  Of course no attacker tries to login as you.


In my opinion password salts have limited usefulness if they are stored right next to the passwords. I say this because if you know the salt and how it's applied to the password then the work of the gpu finding the password is really just the work of scanning passwords. The salt is irrelevant since it takes so little time to calculate. I don't have a good solution off-hand for how to store salts separately or generate them as needed.

That isn't the purpose of salt.  Salt isn't a secret salt accomplishes two things.

1) Salt prevent precomputation attacks.  20,000 computer years is a long time right?  Well lets say your db is stolen today.  Well the strong passwords are safe for 20,000 years right?  What if attacker(s) started hashing passwords 20 years ago using 1,000 computers?  Without salt precomputation becomes a viable attacker.  Lookup tables for just about every algorithm would already exist and your password likely would be compromised before you even thought of it.   Even a password like "KJ#!Ks9d8k" would be instantly brute forced in "seconds" well technically not in seconds but the work can be done ahead of time so it would be compromised seconds after the db was compromised.

2) Salt prevents parallel attacks.  Say a password db has 10,000 records.  An attacker hashes password123.  Without salt they can compare it not against 1 record but against all 10,000.  1 hash = 10,000 attacks.  Ouch. With salt the hacker can hash password123 with the salt of record 1 but the resulting hash is only good for record 1.  To test "password123" against all 10,000 records requires 10,000 hashes.   Which is better security 1 hash = 10,000 attacks or 1 hash = 1 attack. 

Salt isn't a secret.  Salt is designed to limit the attacker to hash per attempted password per account in realtime.  Nothing more.
8752  Bitcoin / Development & Technical Discussion / Re: Should bitcoin lower the transaction fee? on: August 16, 2012, 11:43:40 PM
The wording of your question implies it hasn't already been done.  The fee was lowered to its current value when Bitcoin exceeded $20 USD per BTC.   At this point there is no reason to lower the fee further.  Maybe when 1 BTC = $100 then cutting the minimum fee by 80% would make it equivalent to the prior cut.

Still the min fee is likely going to be less and less important in the future.  I already pay about 5x the min fee (still a fraction of a cent).  The min fee doubling or being cut in half wouldn't change anything for me.
8753  Economy / Currency exchange / Re: ~500 bid for BTC at 13.50 on bitfloor on: August 16, 2012, 10:17:25 PM
get away you filthy sellers.  it is mine.  

[watches powerlessly as sellers eat away at the wall]

1 confirm .... 2 confirms .... 3 confirms ..... 4 confirms .... 5 confirms ....  (crickets)

ATTENTION ALL MINERS:  HASH FASTER DAMMIT!!!!
8754  Bitcoin / Bitcoin Technical Support / Re: Bitcoin client upload saturating my DSL connection. (No bandwidth throttling ?) on: August 16, 2012, 08:35:18 PM
It might be possible under CLI but there is no such feature in the QT Version. 

https://en.bitcoin.it/wiki/Running_Bitcoin#Bitcoin.conf_Configuration_File
8755  Bitcoin / Development & Technical Discussion / Re: Password Hashing and Storage on: August 16, 2012, 06:57:45 PM


Nice find.  The use of "fast hash" algorithms for password hashing has been a pet peeve of mine for some time.  GPUs simply make the problem a couple magnitudes faster.  As OpenCL capable hardware makes it way into lower end computers expect botnets to gain a magnitude more hashing power per node.

To anyone clinging to outdated ideas like using SHA-1 (or SHA-256/512, RIPEMD-160, etc) for storing passwords a simple question to ask yourself.  
Does your login server need to be able to process 4 billion logins per second?  No?  
Then why are you using a algorithm which allows the hacker to brute force at the rate of 4 billion attacks per second?  

Use an algorithm like bcrypt and pick a workload so that your login throughput is only say 20 logins per second (@ 10% cpu load).   That means the average CPU based attacker can attempt couple hundred attacks per second, and the average GPU a mere couple thousand attacker per second.  
8756  Economy / Economics / Re: Thorium power, how is it going in the US? on: August 16, 2012, 05:37:26 PM
Quote
My guess is he was part of US Navy nuclear propulsion program.  They do have some of the best practical application of nuclear theory textbooks and yes they all are classified.

And you believe this punk has access to them?

Still?  No if we was part of the nuke program any material is on a need to know basis and property of the US government.  You do realize that the US Navy accepts "punks" right out of highschool into the nuclear propulsion school right?  It isn't like you need to be a scientist with a PHD.  Was he part of the nuke program?  I don't know.  Just pointing out it wouldn't be impossible for someone remember something from a textbook they no longer have because it is classified.

Also BTW he is correct the fission rate of a material does depend on the temperature among other things.  If a reactor gets too hot it becomes fission hostile.  Not all neutron strikes will cause fission, very few actually do and sustaining a chain reaction requires certain temps and speeds (neutron velocity).
8757  Economy / Currency exchange / Re: FastCash4Bitcoins Support Thread on: August 16, 2012, 05:34:56 PM
Are you able to offer a payout option to my existing netspend reloadable prepaid visa

Does netspend allows you to load it from ACH (Direct Deposit)?  If you login to your prepaid card's online account you may see an option for funding by ACH (Direct Deposit).  If you do we just need the routing #, account #, and bank name (may not be NetSpend).
8758  Economy / Economics / Re: Thorium power, how is it going in the US? on: August 16, 2012, 05:29:29 PM
Classified

LOL

My guess is he was part of US Navy nuclear propulsion program.  They do have some of the best practical application of nuclear theory textbooks and yes they all are classified.
8759  Bitcoin / Project Development / Re: Bitcoin-Rates & Calculator *v0.1 Online* on: August 16, 2012, 03:59:34 PM
Yeah that is the concept but integrating it into a web front end makes it more user friendly.

Kinda like the image-host equivalent for BTC prices.  A simple web form and you get cut & paste code for putting on a webpage or forum.
8760  Bitcoin / Bitcoin Discussion / Re: CBC looks at the Silk Road on: August 16, 2012, 03:50:58 PM
I say 20 years tops.  The "legalization/decriminalization/regulation" vs "continued failed war on drugs" have a significant age bias.  As the boomers start to die and their influence wanes policies will change.  I am not just talking about 18 year old stoners.  Even in the 20-40 year old, non users demographic there is a lot more support for realistic drug policies.
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