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861  Bitcoin / Development & Technical Discussion / Re: cvTokens - Stable currency without trust on: May 25, 2013, 10:46:24 PM
I understand your position. However, I lost all enthusiasm for your proposal when I realized it was impossible to implement. In particular, it is not possible to sign transactions over to unknown specific parties ahead of time.

Given the vague details, I may try to figure out how it is possible to do what you are talking about with testnet3 scripts, but it is not currently a high priority for me. If the new scripts "do the impossible", they may actually be a security risk.

Quote from: Sir Arthur Stanley Eddington, The Nature of the Physical World (1927)
The law that entropy always increases, holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations — then so much the worse for Maxwell's equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.
862  Bitcoin / Bitcoin Discussion / Re: Primer for a P2P Distributed Exchange on: May 25, 2013, 09:55:12 PM
...
FIAT is toxic to an automated distributed P2P exchange.
...

I am not sure point 3 is possible without virtual tokens and the resulting central point of failure. If you want to wait for 1 confirmation while trading with bitcoin: the wait will be anything from seconds to over and hour; with the expected wait time being 10 minutes.

I have a 7th criterion to add:
7. It must not be assumed that the individual users have access to less information than the network as a whole.

As mentioned, the are numerous P2P exchange threads popping up. The ones that sound the most plausible on the surface are also the most flawed: That the network as a whole can somehow authorize things that individuals can't. This violates the laws of the universe, cause and effect, The second law of thermodynamics, if wishes were horseshoes, or whatever you want to call the DRM problem.

I am embarrassed to say I was convinced by the CV token thread for just over 24 hours.
863  Bitcoin / Development & Technical Discussion / Re: cvTokens - Stable currency without trust on: May 25, 2013, 04:30:30 PM
Having though about if for more than a day, I think there is a fundamental problem with the proposal: The 'network' appears to have more information than the participants. Namely: the Bitcoin private keys for "collapsing back into Bitcoin" if no backers are available.

Questions:
  • How are bitcoins signed over to the CV token network?
  • If no backers are available, how are all of the participants paid out?
  • If the network has the private signing keys for those bitcoins, what prevents a bad actor from simply spending them?
  • On the assumption you are using n-m type contracts, does that mean each time the rolling auction updates, a new massive transaction (with many inputs and outputs) has to hit the Bitcoin block-chain? What happens if not enough people sign the previous contract? What happens if there is a delay confirming the transaction on the Bitcoin network?
  • How much time do the backers have to back pay-outs? Do they risk loosing all of their Bitcoins backing the CV tokens if their Internet connection goes down for an hour?
  • You say that this can be implemented either with existing transaction types on the Bitcoin network, or new transaction types. What new transaction types would you like to see?
864  Bitcoin / Bitcoin Discussion / Re: Primer for a P2P Distributed Exchange on: May 24, 2013, 05:07:18 PM
minted bars like this one designed to break apart in small groups of 1g bars or as individual 1g bar are great for our future p2p bitcoin gold exchange. gold is the solution. i read people waiting more than 20 days for wire transfer from mt gox or accounts frozen for id problems etc. that is crazy! nobody has the right to interfere with your private transactions. with the gold exchange there will be no such delays or interference. you can do it over the net or by visiting your nearby bullion dealer. nobody will get in your way.

fiat --> gold --> bitcoins
bitcoins --> gold --> fiat

Gold dealers are required to report large suspicious transactions in Canada, and likely other countries as well. Gold is also much easier to counterfeit than Bitcoin.
865  Bitcoin / Bitcoin Discussion / Re: Why does there need to be a limit on amount of transactions? on: May 24, 2013, 03:40:57 PM
So there are a couple scenarios:
a) limit totally removed from code. unlimited block size. Tomorrow a miner could produce a 80GB block if they desired to
Really? If the 1 MB limit was lifted right now via a simultaneous upgrade of the entire network, what would actually happen if a miner tried to produce a 80 GB block 10 minutes from now?
Assuming the outputs can't be spent (remember, this was an evil miner doing this): 80GB must be stored forever. To put that in perspective, I was hopping to buy an 80GB SSD for my full node, and simply upgrade as the block-chain gets too large. I was hoping that would be on the order of a year or more, not 10 minutes Tongue

Edit: since 80GB would take a long time for most nodes to download, such a large block may actually get orphaned because it does not propagate fast enough.
866  Bitcoin / Bitcoin Discussion / Re: Who do you trust to create a wallet key for you? on: May 24, 2013, 03:20:19 PM
I have thought about producing Bitcoin checks; contracting out the printing. I think to provide a secure mechanism you need to prove two things:
  • That there is no way that you, your equipment, or contractors can know the private key.
  • That when examining a suspect document, you know whether or not you printed it (or if it is a fake).

Proving the first point involves generating the private key with a secure offline printer and computer. Documents should be kept under seal at all times. Cameras (including cell phones and video cameras) are not allowed in the printing room. Hopefully the private keys should be long enough that nobody can memorize them just by glancing at them. The printer memory should be wiped after every run. This involves knowing a lot about how the printer works.

Proving the second point involves applying some kind of mark to the document that uniquely identifies the printer. I was thinking silk-screen with the date placed over top of a seal that you scratch off. Used silk-screen would be damaged and kept under lock and key so that they can be retrieved in the case of a dispute.

867  Bitcoin / Development & Technical Discussion / Re: cvTokens - Stable currency without trust on: May 24, 2013, 05:49:12 AM
I bookmarked this thread.

Governments can use CVtokens to accept tax payments backed by bitcoin. I bring that example up because governments would have the capital to set such system up. (And I do not want to disclose exactly who I shared the link with at this time)


868  Bitcoin / Project Development / Re: Decentralized, Trust-less, Multi-Currency, Interest-bearing, Bank and Exchange on: May 24, 2013, 01:14:53 AM
One thing I found confusing is how a dscoin is supposed to represent crypto-USD. Your recent post helped explain it.

Your whitepaper never uses the term "mortgage". It is also not clear what happens if we try to simultaneously try to use DScoin to represent different currencies (even gold). Obviously, each currency would have its own dscoin exchange rate.

Let's assume that loans in DScoin represent value approximately 50:50 in USD and Euros.
If we assume 2 USD buys 1 Euro, that means 2/3 of the DS coins represent USD, while 1/3 represents Euros.

Bob wants to lend $100 crypto-USD to Alice.
Your white-paper  says that bob should issue a -$100 USD bond (-100 DScoins) to himself and credit Alice with $100USD (100 DScoins).
How are these represented in the block-chain? How does the interest calculation differ for negative amounts?
How is rounding handled? (simply a technical problem, I believe)

Let's now assume a week passes and the US government defaults on their debt. The value of the USD drops in half relative to other currencies. Suddenly it is possible to buy 4 USD with 1 Euro. Since 2/3 of the DS coins represent USD, that pulls the value of DScoins down as well. However, the other 1/3 represents Euros, which tends to pull the price back up.
1/2*2/3+2/1*1/3=1/3+2/3=1
Since the value represented by DScoins in my example was evenly split, the final value of DScoins does not actually change (it normally would). However, 1 USD now only buys 0.67 DS coins, while one Euro now buys 2.67 DS coins. Now it gets weird:
Assuming no actual reference to USD value is stored in the block-chain, Bob's loan to Alice now looks like this:
Bob: -$150 USD
Alice: $150 USD
If Alice and bob were using Euros, they would have lost money due to the crash of the US Dollar.
Same example in Euros:
Bob: -50 Euro -> -37.50 Euro
Alice: 50 Euro -> 37.50 Euro

I am not sure if that behavior is intended, but DScoin may be able to serve as a basket currency if it is actually routinely used as an intermediate crypto-currency.

869  Alternate cryptocurrencies / Altcoin Discussion / Re: [ANN] USSC Crypto-P2P-Server | Decentralized P2P Exchange & Application on: May 23, 2013, 04:11:44 PM
The wallet files are internally encrypted where? The use of the term "P2P" (Peer to peer) implies that all nodes (users) have access to the database.

If the users (who are also servers) do not have access to the wallet files, why are they stored at all?

870  Alternate cryptocurrencies / Altcoin Discussion / Re: [ANN] USSC Crypto-P2P-Server | Decentralized P2P Exchange & Application on: May 23, 2013, 08:06:05 AM
USSC Litecoin-P2P-Server - A Decentralized P2P Client-Server Application & Exchange For Fast Transactions That Utilize Any Cryptocurrency

Application Features:

...

7. Double spend attacks are mitigated by denying end-users access to wallet.dat files or banks. [Wallet.dat files are internally encrypted].
.....


DRM Does not, and can never work. Assume the distributed database is public.
871  Bitcoin / Bitcoin Discussion / Re: Primer for a P2P Distributed Exchange on: May 23, 2013, 07:42:45 AM
I read this thread, some related threads and though about it for a few hours (have not read newer posts).

FIAT is toxic to an automated distributed P2P exchange.

The traditional banking system relies heavily on trust. If something goes wrong, transfers can be reversed. Even Wire transfers can be reversed up until the time they clear; which is apparently not very instantaneous anyway.

The traditional banking system is also heavily regulated. You may need a Money Service Business license. You may need a license to act as an escrow. If a trade goes wrong, the disinterested third party may not have enough information to make a decision (has been mentioned in this thread).

In person meet-ups only solve some of those problems (by using cash).

A P2P Distributed Exchange MUST:

  • 1. Be without any central points of failure, since a government or two WILL be coming after it one day. I suggest a Bitorrent-like software schematic.
  • 2. Show everyone a very large number of possible trades to choose from, (thousands?) so assets can form a stable price. (e.g. a Bitcoin is going for $120)
  • 3. Transact trades pretty much INSTANTANEOUSLY, so when you're watching a graph and want to trade at a very specific time you can do so. (This is extremely important for arbitragers and other traders who help keep the price fluctuation down.)
  • 4. Offer Graphs and APIs for for graphing like MtGox does.
  • 5. Have three-user (trustless) trading, so a non-interested 3rd party always hosts the trade between the buyer and seller. (And should provide Escrow too!)
  • 6. Hold and transfer VALUE, not just IOUs. (With Cryptocurrency this is easy... With fiat? Not so much.)

Those are my must-haves. I will never spend a second helping out any software that doesn't meet all 6 of those criteria. You shouldn't either. Again, if you know something I've overlooked, feel free to add it below.

I am not sure point 3 is possible without virtual tokens and the resulting central point of failure. If you want to wait for 1 confirmation while trading with bitcoin: the wait will be anything from seconds to over and hour; with the expected wait time being 10 minutes.

As recently as March 2011. Microsoft was still recommending against setting your hardware clock to Universal Time (there is now a hotfix for Windows 7). This means that Windows machines can not guarantee that the clock is more accurate than within 2 hours (during a time-change). POSIX systems, such as GNU/Linux can not guarantee that the clock is more accurate than within 1 second (during leap seconds). As a result, choosing the arbitrator based on combined latency may be problematic. You would have to find a way to compute third-party latency without trusting all of the nodes.

872  Bitcoin / Mining / Re: Is my Kill a Watt wrong? says pulling almost 1300W from 1200 W PSU? on: May 21, 2013, 10:21:26 PM
TL;DR: I ran through the calculations to find out how much extra power would be drawn if the power supplies have mismatched voltages. The result was about 3 watts.

Whoa.  I don't understand any of that.


I do have the PSUs wired together correctly now. (I think)


I used this guide.

http://www.burningissues.net/how_to/power/adaptor.htm

That guide should be fine. The black wires (ground) are tied together. I prefer to use a pin/small screwdriver to remove pins I don't want, rather than cut them all (I used that technique to convert an old Dell PSU to ATX).

I took a second look at that guide. For some reason, the have the Power Good signal (pin 8 ) tied to ground (pin 7). Power good is 5V, ground is 0V. Assuming a source resistance of 0.1 Ohms, that may explain 50 Watts of power draw. I would cut that loop. If some power draw is required, I would use a 10kΩ resistor.

873  Bitcoin / Mining / Re: Is my Kill a Watt wrong? says pulling almost 1300W from 1200 W PSU? on: May 21, 2013, 05:37:26 PM
I don't think the Kill-a-watt is wrong. Something is probably wrong with your dual-PSU setup.

I suspect the grounds should be tied together (especially if you are drawing from two branch circuits), but that may cause ground loops. The power supply box may have a hole threaded for a ground screw. You should not be continuously drawing more than 12 Amps from a 15Amp 120Volt circuit anyway (load is supposed to be de-rated to 80%).

If there is a voltage difference between the two supplies, you may be getting enough current flow to explain the results described. V=IR -> R =V/I -> (12V)/(1200W) -- (P=IV -> I=P/V) -> (12V)(12V)/(1200W) = 0.12 Ohms
Power supply voltages are supposed to be within 5%: 12V x 5%= 0.6V
Current flow if power supplies mis-match: V=IR -> I=V/R -> (0.6V)/(0.12 Ohms)= 5 Amps
Power = IV -> (5A)(0.6V)= 3Watts.

Hmm, never mind. That does not appear to explain it.
 
874  Bitcoin / Mining / Re: I am thinking of mining, but wary of downloading so many programs. Need advice on: May 21, 2013, 04:34:10 PM
Buy a computer just for mining.

Very few viruses can withstand a proper disk wipe. I recommend Derik's Boot And Nuke (dban). Note: that program erases all of the data stored on the computer.

You can then install the Operating System of your choice. I recommend a GNU/Linux distribution. While not immune to viruses/malware, you will have a harder time accidentally running them.

Edit: buy a second computer (does not have to be an expensive one) just for your bitcoin wallet. Get one with 4GB of RAM so you can run Armory. That software relies on the reference client. I suggest this because it does not sound like you are able to secure the computer you use for day-to-day usage.
875  Bitcoin / Hardware / Re: List of Avalon ASIC Board assemblers in North America/US on: May 13, 2013, 07:38:59 PM
I sent an inquiry to a local assembler in Edmonton. Have not heard back yet (they had only a few hours to read it).
I don't have the $100K+ capital to order a complete run (625 klondike 16 boards) without a local group-buy. Before the boards are finalized, I think exact prices are probably a little premature.

(ninja'd)
876  Other / CPU/GPU Bitcoin mining hardware / Re: Project: Stealth Mining Rig on: May 12, 2013, 05:54:52 PM
I think I would have the side fans pull in fresh air (pressurizing the case, making the GPU fans do less work).

If you can wait, I would consider using ASIC for a stealth mining rig. A mini ITX board should leave lots of room for 4 of klondike 64 boards. I have not investigated how much case modificatuion would be required to mount them though.

https://bitcointalk.org/index.php?topic=190731.0

200W should be more stealthy than 800W Smiley
877  Other / CPU/GPU Bitcoin mining hardware / Re: PSA: Malta 7990s are NOT suitable for mining! on: May 03, 2013, 09:35:20 PM

Here we go again, you're forgetting TDP is not max capable power draw. The specified TDP is only what the stock heatsink is required to dissipate. What do you think happens when you overvolt and overclock? Same goes for cpus. An i5-3570k has a tdp of 77 watts but overclock it and power consumption can easily double that number.

Somebody is wrong on the Internet.

For electronics, TDP is the same as power draw, to the point that it is sometimes easier to measure the change in temperature than the actual power draw. When you overclock or over-volt a chip, you change the TDP (hopefully not in a way you can't compensate for: such as using a lower ambient temperature).

Molex connectors next to PCIe slots are not part of the slot. Those connectors are likely there becuase the slot connector can not supply more than 75W safely, as stated by the spec quoted by dogie. But what do I know? I wash dishes for a living.

PS: RE: your claim 375Watt TDP equals ~500Watts of power draw. I have 2 possible theories of where you got your information:
1. Online Power supply calculators grossly overestimate the required power. They either want to sell you a large PSU, or assume the PSU you purchase will be sub-standard.
2. Volt-Amps (at the wall) is NOT the same as Watts. For non Power-factor Corrected power supplies, you "waste" about 1/3 of the current (assuming power factor of .67, if my math is right). This wasted current causes resitive heating in the wiring, but otherwise does not draw any power. This happens when the current peaks do not line up with the voltage peaks in the power cycle. It means you get current flow at the zero voltage crossing. (Power=(current)(voltage), by example  (5A)(0V)=0W)

878  Bitcoin / Mining / Re: BFL is shipping on: May 03, 2013, 08:04:06 PM

Yeah, I check two days ago and didn't get any popups with status as processing.  So all is well right?  WRONG!  I logged on just now and got the popup to accept or refund options.  So keep checking back for that pop up screen.   Angry

Wonder how much bigger is the box now...  

<Image trimmed>

After accepting, status shows as "Pending acceptance".

tb

That form does not tell you how much power the shipping devices actually draw. Last I heard, they have up to 50% more power consumption than expected. However, in this thread people are saying the power consumption is 5x (400% higher) than expected. Without a link for more information, that pop-up does not apear to give enough information to make a decision.

Incidentally pop-ups probably wouldn't work for me since I don't use JavaScript. I just sent the an e-mail in the last few days asking if it was possible to order an actual shipping product. Everything on their product page appears to be available only for pre-ordering. I was hoping to order single once I get my bitcoin node up (securing Business-class Internet took 6 months).

I wonder how much the diffculty will jump >.>
879  Bitcoin / Bitcoin Discussion / Re: "Required" upgrade for Bitcoin-Qt/bitcoind versions 0.7.2 and older on: March 19, 2013, 06:24:05 PM
Sez who? Bitcoin central control?

Says the miners in control of the majority of hasing power, after consultation with developers. There used to be a link to a thread including Gavin's diplomatically worded e-mail at the top of the forum.

Was only able to find this earlier thread where they ask miner to revert to 0.7
https://bitcointalk.org/index.php?topic=152030.0
880  Bitcoin / Bitcoin Discussion / Re: "Required" upgrade for Bitcoin-Qt/bitcoind versions 0.7.2 and older on: March 19, 2013, 04:59:28 PM
I think required is the appropriate wording. only 0.7.2 is required (with work-around), 0.8.1 is recommended.
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