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 1 Bitcoin / Development & Technical Discussion / Re: NSA and ECC on: October 02, 2013, 07:09:20 PM Quote from: BurtW on September 30, 2013, 04:19:11 PMOur group is prime and has no sub groups so any point should work as G.This brings up something that I have been wondering about:If any point will work equally well for G why not use an "easy" point or an "obvious" point?x = 0 or x = 1 or x = 2n all come to mind.Anyone have any idea why G is not a more "obvious" starting point?Well, the point must lie on the curve, so it must satisfy   y2 = x3 + 7 (mod p).So x=0, means y2=7, which has no solution for an integer y, so there is no point on the curve with x coordinate 0.Same for x=1,2,3,4,... I think you can go on for a while before finding a solution that way.I think there is no "obvious" solution, so one starts with a "random" value for x and incrementing this until x3+7 has an integer square root.I saw some posts of people generating their own curves incorporating hex-art and/or hashes of "copyright notes" into the value + a counter.It really should not be different, the only thing is everybody needs to use the same G otherwise the key pairs (public/private key) don't match.
 5 Bitcoin / Development & Technical Discussion / Re: Exact binary map of database blockchain?! on: May 12, 2013, 09:28:33 PM @LvM: Like others have said before in this thread, you fail to see what Bitcoin really is, because you keep thinking in your own environment of bank accounts.What Bitcoin tries to resolve is something completely different !Let me try to explain the basics:Centralized versus decentralized:If a person A has a bank account with bank B and wants to send some money to person C that has a account at bank D, then this is what happens in your world LvM:person A gives bank B (and only bank B) the authority to "send" the money to bank D. This involves central authorities (bank B and D) that have to be trusted: bank D trusts bank B (that the transaction is legit, that they are not double spending money or creating money out of thin air), and person C trusts bank D that he can get cash from his account that was credited.I suppose you can understand the above (and probably better then I do).Now LvM, ask you the following question: what happens if there are in the above scenario NO BANKS involved AND A and C don't trust each other (as they are strangers) ?To put it in other words: person A wants to send some money to person C. (And afterwards, person C should be able to spend this money to another person E)This is exactly the problem that bitcoin solves !We have two problems: 1. C will only accept the money if A can prove he "owns" the coins: that is why the transaction is signed cryptographically by A to prove he owned the coins. And with the transaction, all coins are transferred to an address "owned" by C (that is, only C can sign the spending, as he is the only one that knows how to), and "the change" to another (or the same) address "owned" by A.Due to the crypto-magic, C does not have to trust A: he can easily verify (and everyone else looking at the transaction) that the signature is correct, and the signature is nearly impossible to compute by anyone else then A. 2. A malicious user A could try to send his coins not only to person C, but at the same time send them to X (here is your impossible double-spending). Both C and X can verify the signature, which will be correct. But which of those transactions is the right one ? The solution that bitcoin offers here is the "proof-of-work" blockchain: the transaction that is recorded in the "best" blockchain will be recognized by everyone as the correct one. Nobody needs to trust anyone, no bank needs to authorize something. NICE, ISN'T IT ! The company you work for is not necessary anymore So here you have it:I want to spend Y coins I received (from mining or from others) to person Z: I make a transaction and send it to the network. After a while, it will be included in a block, and after some more time, it will be "buried" deep enough in a chain of blocks so that it becomes nearly impossible to change it: now everyone in the network will happily accept that person Z owns Y coins.
 6 Bitcoin / Hardware wallets / Re: [BOUNTY] 1BTC for hardware wallet name on: November 13, 2012, 10:30:25 PM bStick    (b from bitcoin, Stick from USB stick; could also be Bitcoin Secure Transaction Initiator and Coin Keeper, or something similar)UBiStick  (both .com and .org available)
 8 Bitcoin / Development & Technical Discussion / Re: Refreshed the scalability wiki page on: October 17, 2012, 08:37:37 PM Quote from: Etlase2 on October 16, 2012, 06:47:11 AM"As of October 2012 (block 203258) there have been 7,979,231 transactions, however the size of the unspent output set is less than 100MiB"You need to back this up, because from what I recall estimates were between 70-80% of the current block chain's size, which, even today, is definitely not 100MB.You probably recall the correct percentages (70-80%) but that's the percentage of spent outputs, which could be forgotten.I can confirm the following around block 202287 (using my BiRD client which only keeps track of unspent transactions):2443854 unspent transaction outputs, which is about 30% of all transactions (see 7.9M txs at block 203258)the MySQL database containing all the necessary data to be able to spent those outputs, i.e. creating a valid (unsigned) tx, is about 316Mb in size when converted to an uncompressed CSV dump (simple text file)compressing this CSV file yields only 110Mb of data.You can download the client and some CSV's here.