Bitcoin Forum
April 27, 2024, 09:59:42 PM *
News: Latest Bitcoin Core release: 27.0 [Torrent]
 
  Home Help Search Login Register More  
  Show Posts
Pages: « 1 ... 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 [76] 77 78 79 »
1501  Alternate cryptocurrencies / Announcements (Altcoins) / Re: [ANN] Freicoin: demurrage crypto-currency from the Occupy movement (crowdfund) on: June 30, 2012, 02:43:13 PM
You trade your mined freicoins for BTC, but the counter-party to that transaction doesn't want to hold on to freicoins any more than you do.

Do you really think that people will spend bitcoins to buy freicoins THAT THEY DO NOT WANT? Really?

Of course they will. The question, as always, is at what price.
1502  Alternate cryptocurrencies / Announcements (Altcoins) / Re: [ANN] Freicoin: demurrage crypto-currency from the Occupy movement (crowdfund) on: June 29, 2012, 10:52:35 PM
Actually that really is a coincidence (besides, Frei/“free, unencumbered, liberal” and Fried/“peace” are related lexicographically more by chance than by etymology).

“Freicoin” was the name given to a hypothetical bitcoin-based demurrage currency promoted by @jtimon on this forum about a year ago. It was through conversations with jtimon that parameters of this proposed alt chain were set. “Freicoin” itself is an nod to “Freigeld”, the hypothetical state-backed demurrage currency used by Gesell in his economic theories. In this context, “Frei” means free, no-cost, or unencumbered, and is a reference to the approx. 0% interest and easy access to credit it would provide.

Sorry, it's a bad idea to make this joke before you explained the origin of the name.
1503  Alternate cryptocurrencies / Announcements (Altcoins) / Re: [ANN] Freicoin: demurrage crypto-currency from the Occupy movement (crowdfund) on: June 29, 2012, 04:11:25 PM
Second, choose a new name. Forget about coin being in it and think of the name as your key sales tool. Freicoin is too German-sounding for US users.


What would you propose this coin be called?

I think the name is selected partially out of the vanity of its creator.  Wink For example, the Google "Page"rank did not refer to "webpage."

The first US coin to have a metal value less than its indicated value carried the name "Trime" which seems to me to be a pun. Perhaps this coin could be called the "Trius."
1504  Bitcoin / Bitcoin Discussion / Re: Bitcoin Pesudocode Client on: June 28, 2012, 02:01:50 AM
http://bitcointools.googlecode.com/svn-history/r2/trunk/NOTES.txt

http://james.lab6.com/2012/01/12/bitcoin-285-bytes-that-changed-the-world/
1505  Bitcoin / Bitcoin Discussion / Re: Bitcoin Pesudocode Client on: June 28, 2012, 01:22:20 AM
https://en.bitcoin.it/wiki/Original_Bitcoin_client
1506  Alternate cryptocurrencies / Altcoin Discussion / Re: Nurturing AlternaCoins on: June 26, 2012, 12:44:32 AM
Gavin, perhaps you should consider the good things about alternative chains--

1) Keeping other block chains in mind promotes writing "good", bottom-up code where everything is properly encapsulated, and easily extendable by the alternate chain authors. Obsession with "good" code can be taken too far, but programming with alternative chains in mind would actually help you improve the official client.

2) Additionally, the kinds of changes many have suggested to improve the official client's alternative currency support would improve Bitcoin itself. For instance, etothejpi's tree of unspent outputs is a type of alternative chain. Additionally, namecoin is another alternative chain that has some practical value to Bitcoin users.

3) As others have pointed out in this thread -- Alternative currencies help to highlight bad design decisions and why Bitcoin, at the moment, is superior. You can learn from others mistakes.

4) Alternative chains are absolutely necessary for the long term success of Bitcoin. Remember what proof of work was before Bitcoin? It was used as a type of digital notary stamp to prevent spam e-mails.  Proof of work is a digital token that says "I invested some amount of time and computational effort in solving this problem." The primary future use of Bitcoin will likely be supplemental to the actual crypto-currencies most people use. Bitcoin's role in a future economy will be much like the role of the Bureau of Engraving and Printing in the early history of the U.S. Dollar when employees of the U.S. Treasury would sign the individual bills produced by private companies for the Treasury. The role of the signature was to "monetize" the paper, much like the role of the Bitcoin will be to "monetize" alternative currencies.
1507  Alternate cryptocurrencies / Altcoin Discussion / Re: Nurturing AlternaCoins on: June 25, 2012, 12:01:40 PM
Gavin--

What is this post about?

Did somebody say something stupid to you?

We appreciate all the work that you do on Bitcoin.

What is version .0.6.3? The latest version available to the public is .0.6.2.

Thanks.
1508  Alternate cryptocurrencies / Altcoin Discussion / Re: Nurturing AlternaCoins on: June 25, 2012, 11:58:46 AM
How's the fix for the 'time travel exploit' in bitcoin going? That was found and fixed in alt chains a while back.
I don't think Bitcoin requires that fix. The feedback system in Bitcoin is either asymptotically stable in the Lyapunov sense or extremely close to being asymptotically stable. By extrememly close I mean that the maximum amplitude of oscillations that could be introduced in it is on the order of LSB in the very narrow floating-point format that is used to represent the difficulty.

On the other hand the designers of alt-coins cranked up the gain in the feedback loop and applied asymmetric clipping in the feedback signal. The resultant system is probably still stable in the Lyapunov sense but no longer asymptotically stable.

Satoshi either understood the stability problem in the theory of closed-loop control systems or at least consulted somebody who understood the problems.

On the other hand the designers of alt-coins are like kids who stood up with microphone in front of the speakers and cranked up the gain on the amplifier.

http://en.wikipedia.org/wiki/Lyapunov_stability

2112, I'm not entirely sure if you've looked at the code for GetNextWorkRequired. You keep describing it as doing integration when from what I can tell its entirely proportional. Are you making assumptions looking at the graphs on this website? http://bitcoin.sipa.be/

Here is a condensed version of the code with my comments:

//pindexLast points to the last block generated. pindexFirst points the block generated 2015 blocks ago.

if ((pindexLast->nHeight+1) % nInterval != 0)  //nInterval is 2016
return pindexLast->nBits;

//some code to get pindexFirst and limit the gain of the proportional controller to a threshold.

int64 nActualTimespan = pindexLast->GetBlockTime() - pindexFirst->GetBlockTime();

bnNew.SetCompact(pindexLast->nBits);
bnNew *= nActualTimespan;
bnNew /= nTargetTimespan;  // target is 1209600 (two weeks)

The reason this is safe is that the Bitcoin protocol enforces a rough causality for every block accepted onto the network.

My reason for posting this is I'd like to get your opinion on how safe the implementation is.

As far as the graphs on sipa's website, only the difficulty actually exists. The estimates are calculated in this way.

Quote
<sipa> galambo: i use an exponentially decaying average over time (which can be considered an IIR) to calculate averages of block-finding-speed (weighted by difficulty) and average age of recent blocks, and feed those to a maximum likelyhood estimator that estimates average and growth rate for an assumed poisson-like process with exponentially changing rate
<sipa> assuming the actual hash rate is a function of the form A*exp(B*t), it will give a very accurate estimation of A and B
<sipa> but the hashrate that results from this calculation is effectively an extrapolation (it uses data from the past to guess the current speed)
<sipa> which makes it inappriopriate as a difficulty function
1509  Bitcoin / Development & Technical Discussion / Re: Ultimate blockchain compression w/ trust-free lite nodes on: June 24, 2012, 10:46:45 PM

This is a subtle but important point.  A while back I wrote a section about it on the bitcoin wiki.  The Satoshi client never uses "number of blocks deep" as a measure of confidence that a transaction is valid.

A truly trustless thin client needs to be able to be able to verify a recent block's height (that there really are 180,000 blocks before this one and they obey the max-difficulty adjustment rules) rather than its depth (that there really were 6 blocks built on top of it -- also known as confirmations).

It's possible to do height verification probabilistically without 2GB of disk+download, but you need more than a tree-of-unspent-transactions to do it -- the block chain has to look more like a tree giving you multiple hash-secured O(log n)-long paths from any block to the genesis block).  These "shortcut ancestor links" can be added without 51% agreement.

How will the lightweight node know the path hashes are incorrect and to reject that part of a block?

I can see how the thick clients can verify this, but an incorrect path would require all of the thick clients to reject the block if it contained a false path. I think this means another protocol decision point like P2SH.  Otherwise, we'd have ignorant thick clients forwarding malicously crafted "tree transactions" to the light clients.

This isn't meant to be a gotcha. I like your idea (a lot), but I'd like some clarification. I've only started looking into this part of Bitcoin and I'm not a very big data structures guy.

I also don't understand why you think these could be added without the "51%."
1510  Bitcoin / Development & Technical Discussion / Re: Ultimate blockchain compression w/ trust-free lite nodes on: June 19, 2012, 10:02:10 PM

(2)  As echoed by others, I believe that a hard-forking blockchain change is going to only happen in the event of a crisis.  To do so requires more than democracy -- it will seriously impact the entire network in a detrimental way.  There are users who are still using version 0.3.X bitcoin clients not because they want to, but because it works, and they don't follow the forums or Bitcoin news or anything of the sort.  And the hard fork exposes them to all sorts of malicious behavior by others who would exploit their ignorance of current events and manipulate the abandoned chain that they are stuck on.

To maintain confidence in the system, a hard fork is going to need more than democracy -- it's going to need super-majority, probably 80-90% ... and gaining that level of consensus is pretty much impossible for new ideas that are not well-understood -- unless the idea has been in the wild, and in use for many months/years and is already used by 80%+ people.

The idea of using a second blockchain is actually a way of creating a "staging area" for such ideas on the main network (like galambo said) without actually risking exposing that network to any of the unforeseen issues that could arise.  It can be used to add such functionality to the network without actually changing the network.

In this way, the meta-chain can grow and develop as people start using it and understanding it.  People start building infrastructure on the availability of the information in that chain.  Once it has become ubiquitous enough and time-tested as a pillar of a part of the network, then you have 80%+ agreement amongst users without even having to ask for it.  At this point, a hard-fork is entirely feasible -- or at least orders of magnitude less disruptive.

You're right, it's not the only way, but I think it's about as good as it's going to get.

Thank you for your feedback. I wasn't quite sure if people would agree that this could help automate the BIP process.


Maybe I'm misunderstanding the change your talking about. But I think this is dangerous.I use bitcoin because i trust the protocol behind to never change. If the majority or the devs can push a change in protocol, then I'm out. A way to compress the blockchain fine. A fork, hard or soft... mmmmm seems dangerous to me.

The only way you would notice this kind of fork is if you applied the experimental patch to your Bitcoin client. Think about it like another "test net."
1511  Bitcoin / Development & Technical Discussion / Re: Ultimate blockchain compression w/ trust-free lite nodes on: June 19, 2012, 03:44:42 PM
This idea could end up having more uses than enabling lightweight clients.

For instance, forking the main blockchain is practically impossible today. Even if someone came around with worthwhile changes to the storage subsystem or the scripting subsystem we could never implement it. The moment the two chains got out of sync you need two copies of the block chain .dat that are mostly identical.

With this proposal a certain "snapshot" in the metachain could be specified as the branch point for the blockchain. This snapshot could be used to refer back to the legacy system.

The proposal would allow experiments and tests using the real chain. The developers have been sort of paralyzed because they cannot change many things in the implementation because there's not really any way to change it.

If one of these experimental branches became popular enough, a new branch could be created on the official branch with ample notice to all users.

Also, having a chain of snapshots would allow the network to avoid new and unforeseen attacks. If one user managed to do something detrimental in the block chain to his advantage and every other user's disadvantage (like a sustained 51% attack, or an exploit), the community could achieve a consensus to "go back in time" to a previous snapshot with a patched client.
1512  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 19, 2012, 03:13:47 AM
That's not the first picture. And that is the second redesign. You weren't here that long ago, otherwise you would have seen other things. This for instance: http://butterflylabs.com/wp-content/uploads/2011/11/IMG_1817.jpg

And maybe this: https://eclipsemc.com/bfl/bfl-8.jpg <-- 25 Nov 2011, and it hashes! More here: http://eclipsemc.com/bfl/

It was at the point that they discovered that the power subsystem was insufficient, requiring a redesign.

I apologize. To be honest, I hadn't realized how many people had now received their BFL single. However, the circumstances around this company still warrants a high degree of skepticism.
1513  Bitcoin / Development & Technical Discussion / Re: Transaction confirmation data on: June 19, 2012, 01:56:46 AM
On that list, I calculated that there were 4302 TXs that paid an insufficient fee for their priority which was 3.7% of the total. If someone double checks that I would appreciate it.

If I look at all transactions on the list:
Fee-paying transaction average confirmation time: 30.3 minutes
Fee-less transaction average confirmation time: 30.73 minutes

If I exclude the transactions that didn't pay a sufficient fee:
Fee-paying transaction average confirmation time: 30.27 minutes
Fee-less transaction average confirmation time: 29.07 minutes

It wasn't this bad before the transaction volume rose. Back then, there was an advantage to paying the fee. But now the fee-payers have to wait just as long.


Can we be sure about this unless we exclude 1dice from the experiment? Many of the mining pools are now ignoring them and I think this could distort the statistic.
1514  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 19, 2012, 12:42:59 AM
By "finished design" I meant "a design that the forum has had no input into" but I didn't expect you to catch that. They also had a design that never shipped, but that was mining at reduced speed due to poor design choices.

Again, you have no idea what design they had at any particular point in time. This is your personal assumption.
Yeah, just because photos of a finished PCB don't constitute a design. Right. Uh huh.

First reference to EP3SL150 (by ngzhang) 12-1-2011
https://bitcointalk.org/index.php?topic=48863.msg637417#msg637417

First picture of PCB 1-20-2012
https://bitcointalk.org/index.php?topic=53530.msg705354#msg705354

That's a 2 months difference.

And no, photos of a finished PCB do not constitute a design, either. We have no way to tell if the PCB has errors simply by looking at it. These things do not always come back correctly the first time, especially if the designer is inexperienced.
1515  Other / Off-topic / Re: BFL ASIC Announcement - Truth or Troll ? - The LONG CON just got longer on: June 19, 2012, 12:19:09 AM

Nice distortion of the facts. BFL takes payment upfront, then delivers months later. Enterpoint takes payment and then ships immediately.


BFL delivered? What? When? Where? How? To who?
1516  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 19, 2012, 12:14:18 AM
By "finished design" I meant "a design that the forum has had no input into" but I didn't expect you to catch that. They also had a design that never shipped, but that was mining at reduced speed due to poor design choices.

Again, you have no idea what design they had at any particular point in time. This is your personal assumption.
1517  Bitcoin / Development & Technical Discussion / Re: Ultimate blockchain compression w/ trust-free lite nodes on: June 18, 2012, 11:17:08 PM
No clue about any of this stuff, but thank you guys for working on this.  I think it's important to have this sorted out before adoption and use gets really heavy.

I think its important that everybody understand this and I didn't see anyone explaining it in general terms.

The Blockchain is a distributed computer file system containing a double entry accounting ledger. Each transaction has two sides which you may be familiar with from accounting: input and output OR debits and credits. However, a major difference is that bitcoin forces a debit(input) to exist for every credit(output).  Storing all of this takes a lot of space. extra explaination

This proposal will continously "balance the books." In accounting, when you close out the books for the quarter all of the debits and credits are summed, and the difference between the two is entered as a "balance" transaction. Because we know that bitcoin forces every credit(output) to have a debit(input), we only have to keep track of all credits(outputs) that are not claimed by a debit(input) to obtain the balance of each address.

The proposal is for a system to store the references to these unspent outputs in a data structure for quick downloading. It doesn't suggest how this tree would be updated efficiently, or how you would quickly grab all of the unspent outputs belonging to one address. This is under discussion.
1518  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 18, 2012, 03:54:10 PM

They (BFL) suddenly appeared with a website and a promise of extraordinary performance, including a finished design.
You don't know that they had a finished design. This is an assumption on your part.

It's entirely possible that a student could approach the R&D engineers at a local university's EE department for help in laying out the PCB after he knows what plausible components to specify. He would only have to tell them it was for a school project. If I were investigating this I would begin by calling all the universities in the KC, MO area. I would ask them to look at the picture of "ninja lady" and if she was on their payroll.

This same student could not however approach the department and ask them to design a board and specify components that would achieve a certain number of SHA-256 hashes per second.

Additionally, this student wouldn't have the experience necessary to implement the SHA-256 algorithm and spend the months necessary to unroll and route and debug the implementation.

Every manufacturer of FPGA devices, except BFL, followed the same formula: They announce exact specifications with pricing. And then they deliver in a reasonable timeframe.

BFL is not following this formula. Use your imagination as to why. (PRE-)BUYER BEWARE.

1519  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 18, 2012, 11:43:59 AM

You're mem, aren't you?  +1 for the ignore list just in case.  Furthermore, these guys aren't geeks;  they're educated individuals.  You've obviously got nothing to add, it'd be my suggestion to shut-up and maybe you'll learn something.

The forum basically designed the single for BFL.

And, after the forum did all the extensive research, a pcb carrying the EP3SL150F780 chip ended up getting shipped to ngzhang.

It was claimed to be "broken." From the sound of it ngzhang had to hack the shit out of the board to probe the chip.

We'll never be sure if this was simply an altera chip on a pcb or an actual functioning product.

About the only thing I'd believe at this point, with the situation being so strange, is if someone like eldentyrell or ngzhang got their hands on a functioning BFL single.

Don't do these people's research for them. Don't post plausible designs the the forum. You're only making it more difficult to find out if this is a legitimate company by discussing their "products" in such depth.
1520  Other / Off-topic / Re: Leading SHA256 Solution Provider Acquires Venture Capital Funding on: June 18, 2012, 01:17:00 AM
See this is the stage where all the geeks on the forum argue until they basically come up with a plausible design for BFL's products given their vaguely specified performance claims.

And, if BFL is a dishonest actor, they could use this information to continue being dishonest.
Pages: « 1 ... 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 [76] 77 78 79 »
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!