People have upload majority of the block chain. So download the file and stick it in. 2hrs becomes 20mins tops
However, the client doesn't verify the chain if it is on the hard drive. What they need is a -verify_chain command line option. This would automatically happen the first time you start the client or if the date on the block chain file is updated. That would still take a few hours. Yes, believe it or not, verifying the chain is the bottleneck. |
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Now we see, that even if you invest tremendous costs in getting a huge majority of computing power, you can't do a lot of harm.
You are thinking so small... An attacker with over 50% of the hashing power doesn't need to broadcast their blocks. They could very successfully eat a month's worth of transactions if they wanted to. Oh, and if any of those transactions used newly minted coins, they are now permanently reversed. |
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I don't think it's been done yet?
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If you have an immediate need to be allowed into the forum beyond, please post your request here. Reasons such as "I'm not a spammer" will be ignored. You must provide evidence that shows that you understand more about Bitcoin than the average newbie would or that what you want to post can only be done in another forum. Try to be as specific as possible.
Much obliged.
Edit: Many people posting here have already met the 5 posts and 4 hour requirements. If you see "Jr. Member" by your name, you don't need to post here.
I certainly don't know more than the average newbie, but I was hoping to sell a few things to earn some bitcoin. Edit by Maged:
What are you thinking of selling?Hi Maged, I think I sent you a PM last night. The more I read and learn, the more I like the idea of opening a Bitcoin Bookstore. My inventory is a bit small right now, but I'd like to open it up and see how much interest there is. I whitelisted you this morning... |
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MtGox got my money too.. Around $XXX worth.. horrible that they haven't communicated back with me yet either and I PM'd MagicalTux on this forum and yet no answer. Horrible that people like this can do something like that, however I'm contacting Dwolla and hopefully others who sent their money to them through Dwolla will contact too and cancel their accounts.
Don't contact Dwolla, they can't do anything. Also, PMing MagicalTux won't work, since he never really checks his PMs. Contact MagicalTux on IRC. |
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By the way, something else I've been wondering (and an excuse to get to 5 posts): what is the incentive for a node to include any transaction in their block for free? The only incentive is that it will help get more people to be willing to use Bitcoin. If you have a lot of transactions, isn't it going to take longer to hash? If I was selfish, why wouldn't I calculate a block and only include my own coinbase transaction and nothing else? It DOESN'T take longer to hash. There's no reason NOT to include transactions. Similarly, as the network picks up popularity aren't we running the risk that we'll have to start including millions of transactions in every block? Even if the difficulty adjusts to accommodate the slower hashing, won't the blockchain get untolerably large (in terms of storage space)?
I suggest reading this wiki page: https://en.bitcoin.it/wiki/ScalabilityEdit: to clarify, it's not the whole block that is hashed, just the headers, which includes the Merkle root. The amount of data hashed does not change - regardless of the number of transactions. |
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These guys are either *really* incompetent or crooks (or perhaps still overwhelmed by the number of claims--unlikely in my view after an entire week!).
Even a MtGox employee's claim got rejected. Just keep giving more information. |
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Go back to the claim page listed in the email you got after the first step where you entered your password. That should provide more information. If you never got to the page where you submit additional info, restart the claim process. What are the best alternatives?
Trade Hill is one (use the link in my sig for 10% discount on commission). Camp BX is also coming out soon. I don't trust the others. |
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So you are saying that the client will not recognize a transaction with a non-standard script, unless someone knows about that transaction and spends the coins in compliance with its script? Therefore, if a script were somehow included in a transaction, the new owner is still bound to the "terms and conditions" of the script, but if they're using the standard client, they won't see it to begin with. Therefore, a vendor would not see the transaction in their history, and they would claim that you never paid them...? That's exactly it. In fact, unless your client is aware of how the script can be solved (such as is the case for the current two scripts), it's (virtually) IMPOSSIBLE for the client to recognize that it can spend the transaction. By the way, who/what is Eligius? They are a major mining pool. There is really only one client right now, Bitcoin-0.3.23. Is there anything wrong/unethical/prohibitive to create a new client? Absolutely not! PLEASE do! We need more competing clients! Even if it is "okay", someone could eventually sneak malicious code into the client. What's stopping that from happening now? Is the official bitcoin client codebase protected against this? Could an attack of this sort cripple the network? Not much is stopping it right now, other than that we're open-source. This issue needs to be solved before we can offer automatic updates. |
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I have spent quite a bit of time studying how the Bitcoin network actually works, but I'm not sure I'm 100%, so these questions will hopefully clarify some of the gaps in my understanding. Given the decentralized nature of the network, there is no single authority that decides which is the "current" block. Nodes assume the longest chain is the "correct" one. So:
(1) If two blocks are computed simultaneously by nodes on opposite sides of the world, both nodes will broadcast valid blocks with the target hashes at the same time. Then the nodes closest to the "winners" will each start extending that chain. Even when they get word of the other chain, they will continue to work on the first one they received. But as soon as one of the chains gets extended, all nodes will switch to that chain, and the other chain will be orphaned.
-- Is this correct?
-- If Deepbit reports a block as "Invalid," is this why? Yes on both counts. (2) Let's assume that a government has a massive banks of FPGAs which are not on the network right now, but actually would be more than 50% of the network speed if they were (not really feasible, but governments have a lot of money...). Now, instead of joining the network, they start building an alternative blockchain branch, starting from some arbitrary block. Because they have more computing power than the rest of the network, they can start building the blockchain faster than the "current" blockchain everyone is working on. Could they build this alternate blockchain branch for 2 months, and then broadcast it to the network all at once? If all blocks in the new chain are valid, and it's longer than the current, then won't all nodes switch to it? Then all the transactions of the last two months will basically be reversed because they "never existed" in the new blockchain? This would seriously disrupt the Bitcoin network... Yes, that is what would happen. To prevent such a disaster, various ideas are being thrown around where, essentially, such a large reorganization would have to be resolved manually by all the other active nodes. However, if someone has a majority of the hashing power, we're still screwed. (3) Are transaction scripts currently disabled in the main Bitcoin client software? If not, then is anything stopping people for using scripts in their transactions? If so, then what is stopping someone from including a script in all their transactions that says no private key is required to transfer the coins onward? Once the main Bitcoin client software starts using the scripts, then that old transaction no longer requires a private key signature and the they can send the coins back to themself if they were never transfered out out of that account.
-Eto
The current client won't make, nor recognize, any transactions with a non-standard script. It CAN, however, verify scripts when they are spent. If you use a script that is spendable by anybody, someone would have to notice the transaction and then spend it. It wouldn't show up in everyone's client automatically. Non-standard script transactions can currently be submitted to Eligius and put in a block for a small fee. |
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Has anybody checked whether jed's password was one that's been publicly leaked yet? I'm interested in how strong it was...
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I need help from someone at MtGox asap. my account has had the password changed and my email address password was also changed. I managed to get back into my email through the question and answer but I cant gain access to my MtGox account.
I have been trying to contact MtGox to freeze my account but they do not respond to me. Its is coming up to 24 hours again and I know I will be loosing $1000. every 24 hours they don't have my account frozen.
is there another way to contact them or get my account frozen?
Contact them on IRC. See the post above yours. |
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I was sent Bitcoins on the 26th but my client doesn't show them in the balance or the transaction yet. I have the latest client. Why is this and how can I correct it?
Do you have all the blocks? We're at 133983 blocks right now. |
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Start your client with -rescan and see if that fixes it.
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Be sure to use the Python 2.x branch, not 3.x.
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OP - maybe you should edit the title of the thread to show the issue has been resolved.
Josh, I hope you don't mind, but I did this for you. |
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Thanks for the fast replay.
Is the block id not a problem when there are many transitions? So all users in the block will win the same amount. Unfortunately, this would be the case. You say, a transaction can be generated unlimited times. Am I right that one would have to manipulate the client for this? Yes, but when you're running a gambling site that has such an obvious vulnerability, it WILL be exploited. |
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