The blockchain is a list of all transactions that have occurred using the Bitcoin currency. Please don't use this tag for the service named 'blockchain.info'.

learn more… | top users | synonyms (1)

1
vote
1answer
76 views

multibit balances wrong, not correct for any individual address

In my multibit wallet, it reports X bitcoins. But no address in that wallet contains exactly X bitcoin, and the total reported amount should be greater than X. The reason this is stranger than ...
3
votes
2answers
159 views

How to create a SPV client?

What are the steps a SPV client takes in order to sync? Connect to a peer Set bloom filter for wallet addresses Download all block-headers since latest checkpoint Request every block again with ...
0
votes
2answers
90 views

Bitcoin URGENTLY Need Blocks Files - Download them from some Website [duplicate]

I have been doing this synchronization procedure (first time) in bitcoin-qt for over 85 hours and it only came to 31 Weeks Behind. Withdrawed from localbitcoins like 95 hours ago and obviously this ...
1
vote
1answer
112 views

Why there are blocks with single transaction in blockchain?

Just opened blockchain.info and found two blocks with single transaction on the main page: 292942 292947 Isn't it strange? More than this, block 292941 was issued just minute before 292942 and has ...
1
vote
1answer
75 views

If more than one coin did the “mini-blockchain” proposal, would that make the weaker coin vulnerable?

So, I was reading this paper as a proposal to the ever growing blockchain problem. In summary, it's security is provided without a full blockchain by having a proof chain with these fields: Previous ...
0
votes
1answer
151 views

get public key from wallet.dat

Is there a way to get the public key of a given wallet.dat to check the balance in the blockchain to avoid having to install the wallet and read all blocks?
0
votes
2answers
190 views

Is there any altcoin with improvements in blockchain download time?

Let me introduce my idea. Given: sizeof( Blockchain ) = 16Gb Downloading of one avi film 16GB from the pirate bay ( 5mb/s ) = 2-3 hours Downloading of bitcoin's blockchain ( 5mb/s ) = 2-3 days One ...
3
votes
3answers
142 views

How is over-spending one block apart prevented?

So, let's say you have a wallet with 20BTC, and you have a flow like so: You send 15BTC to A in block 1 You send 15BTC to B in block 2 What happens if at block 1 there are two chains across ...
5
votes
1answer
76 views

Where is the code that sends generated Bitcoins from mining to the wallet?

I was just looking through the Bitcoin code but since I am relatively new to C++ I was wondering, if anybody could tell me where the code responsible for sending coins generated through mining to the ...
1
vote
1answer
54 views

Bitcoind need blockchain to sign transaction

I'm trying to sign a transaction using bitcoind via rpc. Here is the request I send. signrawtransaction ...
0
votes
1answer
60 views

Cannot allocate memory

EXCEPTION: 11DbException Db::get: Cannot allocate memory bitcoin in ProcessMessage() Downloaded 250k blocks, now it won't run anymore i'm running ubuntu 12.04, I have 20GB HD and 1gb ram. any way to ...
3
votes
1answer
66 views

How is the reward that you got after calculating the right hash added in the blockchain?

I have a question. If for each transaction, the hash is calculated and so the pool who calculates it gets the bitcoins as reward, now getting reward means bitcoins gets added to your wallet, but this ...
0
votes
0answers
20 views

Is there any relation between the block version field and the one of the transaction?

I am struggling to validate my custom miner against the testnet network and I can't seem to add a block of mine to the chain. I've noticed that all the other miners are appending version 2 blocks, so ...
2
votes
2answers
189 views

First block of blk00000.dat from bootstrap.dat doesn't contain genesis block

I downloaded the bootstrap.dat file from the torrent at http://sourceforge.net/projects/bitcoin/files/Bitcoin/blockchain/ and placed it in the .bitcoin directory of a new Ubuntu installation of ...
1
vote
1answer
77 views

Possible to use BlockChain.info and Bitcoin-QT synced?

I've used both BlockChain.info and Bitcoin-QT. Is it possible to use the same addresses on both? I don't have a incredibly large amount of bitcoins, so I'm not worried about it getting hacked into, ...
0
votes
1answer
101 views

How do I iterate through the entire Blockchain using RPC?

I'd like to iterate through the entire block chain using RPC. The process I intend to do is: getblockhash 1 getblock (input of #1 here) iterate through each transaction with GetRawtransaction ...
1
vote
1answer
77 views

What is the fastest way to determine whether an address exists on the blockchain?

All I want is to determine whether a given address has ANY activity on the blockchain. I've seen projects like bitcoin-abe, which might work, but I wondered if there were a simpler way than using ...
0
votes
2answers
353 views

Sending bitcoins from wallet without downloading the blockchain or giving up control

I can generate a bitcoin wallet at bitaddress.org, and I can verify that I have received payments at blockchain.info. But if I want to send bitcoins from my wallet, I know only of 2 ways: Use ...
2
votes
1answer
69 views

Verification of transaction once trasaction is broadcasted

I have few doubts regarding verification of transaction and am trying to find answers from last few days. I agree similar post exist in this portal but I am not getting satisfactory answer for my ...
0
votes
1answer
37 views

Restore New Funds after Blockchain Backup

If I transfer money into my Blockchain account after receiving my Json wallet backup by email, would it restore recently added funds?
0
votes
0answers
36 views

Using a blockchain type system for different purposes [duplicate]

I was wondering, not that I really took the time to investigate much yet but.... Wouldn't it be possible, to do many different things, with the blockchain concept? Maybe i could build a "browser" ...
1
vote
1answer
118 views

Bitcoin blockchain search algorithm and consistency policy

The blockchain looks like a double linked list, and all the transactions are stored into each block. What kind of algorithm does bitcoin use to find a specific transaction efficiently, since the ...
2
votes
2answers
168 views

mtgox failure… any implications for bitcoin/ecurrency protocol design?

last heard, estimates are Mtgox lost about ~$½B ... apparently the current bitcoin market cap is around ~$8B ie Mtgox failure roughly somewhere around 1/16th the entire market cap of bitcoin, a ...
-1
votes
2answers
142 views

pending payment

Three days ago I sent a payment via my MultiBit wallet but it is still marked as unconfirmed, only 4 confirmations. How long it will take this transaction to become fully confirmed? Thanks.
2
votes
2answers
161 views

What happens if I fork an older block chain and rejoin the network later?

Let's call it a "time machine attack". Suppose I have an isolated network of n clients with a significant hash rate, install my client software on that and start mining on an older blockchain. Since ...
1
vote
1answer
110 views

Given that contracts can be formed in the blockchain using scripts, couldn't a contract include a mechanism for facilitating chargebacks? [duplicate]

While I understand that chargebacks, or the lack thereof are an important feature for encouraging merchants to adopt bitcoin, the reverse may be true for consumers. There is probably a balance to be ...
1
vote
1answer
674 views

How to create a bootstrap.dat file?

I want to create a new bootstrap.dat file for a Dogecoin. How do this kind of files are created and how can I create one? What tools should I use? any answers/links/references are appreciated. I have ...
2
votes
0answers
212 views

digitalcoin wallet won't sync

I've had my digitalcoin wallet open for a few days now, hoping it would eventually sync back up but it's seemingly stuck, not necessarily at a specific block, but around 3 days back, whichever block ...
1
vote
4answers
140 views

How much money is a double spend worth?

I keep hearing people say that 0 confirmations are safe at small dollar amounts because it would take more money to do a double spend hack. At what value does it start to become unsafe to trust a 0 ...
2
votes
1answer
49 views

Order of transactions within a block

Does the Bitcoin protocol guarantee that within a valid block, if transaction B spends the outputs of transaction A, A will always precede B? Or is it possible to have B before A?
2
votes
1answer
127 views

Hypothetical situation: the Internet gets split in two, what happens with Bitcoin?

Let's suppose, that at some time the Internet gets split in two, possibly because of wartime, or another possibilities (there was once a situation, when Egypt managed to split the internet in their ...
5
votes
2answers
126 views

How did transaction malleability/DDOS attacks allow an exchange's internal accounting system to get “out of sync”?

This Coindesk article says that: “So as transactions are being created, malformed/parallel transactions are also being created so as to create a fog of confusion over the entire network, which ...
0
votes
2answers
266 views

Is it possible to run bitcoind without downloading the blockchain?

I'm using bitcoind on a project, and I only need to send bitcoins to myself (from one wallet to another), so trust is not a factor. That being said, is there a way to run bitcoind without needing to ...
1
vote
1answer
534 views

Security and recover issues in blockchain.info wallet

I have a wallet in blockchain.info. I'm quite new to bitcoin and would be happy if someone would explain me : (1) what should I do in order to save my bitcoins if something happens to ...
2
votes
2answers
164 views

Is there a database of all transactions?

The blockchain is a database of all valid transactions, but is there a company/project that also logs all transactions which were broadcasted, but didn't made it to the chain? Blockchain.info for ...
5
votes
3answers
307 views

Is it possible to add a miners fee after you send your bitcoins?

I accidently sent btc without a miners fee and i need it to clear asap. But as far as I can tell it's going to take days if it goes at all. Is there anyway I can pay a fee on top of what I've already ...
3
votes
4answers
110 views

Are there any works of science fiction out there that relate to blockchain technology?

It feels like science fiction is lagging behind Bitcoin and the blockchain technology that is powering it. Are there any writers who have discussed similar technology in their stories? Even in the ...
1
vote
0answers
13 views

How to check on speed of the syncronizing progress? [duplicate]

I've got the feeling my network syncronization sometimes stops. I'd like to keep an eye on incoming information. Preferably something that shows XXX Kb/s or that simply shows me the data that is ...
5
votes
2answers
251 views

Does a new block necessarily include all transactions that occurred before its generation? What about network latency?

I read What exactly is Mining? and What are bitcoin miners really solving?, but was left wondering: What happens if a new transaction comes in, whilst mining? To answer that, I found Do transactions ...
2
votes
2answers
144 views

Why aren't bitcoin transactions processed and verified by normal bitcoin clients?

My understanding is that the blockchain is exclusively built by miners. My question is, why isn't that verification done by every bitcoin client - kinda like p2p file sharing programs allowed people ...
0
votes
1answer
83 views

How does one programmatically “walk-back” on the block chain?

I'm thinking (probably erroneously) along the lines of a linked list and C pointers, but how would one follow the block chain from some block all the way back to the genesis block? The previous ...
0
votes
1answer
131 views

Help understanding the blockchain [duplicate]

I am trying to better understand the fundamentals of the BLOCKCHAIN. I am not technical and am hoping someone can offer up an explanation in LAY TERMS. Thanks in advance.
0
votes
0answers
93 views

Transactions show up on blockchain but not in multibit? [duplicate]

1JPEobzLgKo5EKEfDVN8aJ61Pdryse6ccf This address shows transactions I was not aware of for unknown reasons, and does not show up in multibit(version 0.5.16). Which one is accurate, and how can I sync ...
1
vote
1answer
149 views

Running two bitcoin instances on a linux server, can't get peers on second instance

I am running two bitcoin instances using the method described in this previous thread: http://bitcoin.stackexchange.com/a/13584/6024 I have set the new datadir and each instance has a different ...
0
votes
1answer
330 views

LiteCoin Wallet balance does not match block-explorer.com

My Litecoin wallet version v0.8.6.2-beta is showing a balance of 26.579 ltc When I query http://block-explorer.com/address/LejrG23b2HcjqPRbZU8UWFxZhdJTUc75pS it is showing 0 balance. I just sent 2 ...
0
votes
1answer
929 views

How do I find the transaction ID of what I just transacted?

If I send or receive something (with Bitcoin-QT), how can I get the transaction ID of that transaction? context: I'm playing satoshi bones and they have verification code I can run to make sure ...
0
votes
1answer
73 views

Checks to Verify money sent to any address in a transaction

I'm using wallet-less bitcoin daemon (it just syncs blockchain) – the purpose is to read blocks and transactions in them, and do some useful things. This particular question is focused on determining ...
1
vote
1answer
118 views

Bitcoind doesn't find transactions / synchronize / update until last block from Testnet

I set up bitcoind as server. It downloads the testnet blockchain but it is inconsistent with public data: http://blockexplorer.com/testnet/q/getblockcount 182951 (As of 18/02/14) And bitcoind ...
1
vote
2answers
139 views

Do I need to wait for blockchain to complete to use private key elsewhere?

As the title says: My blockchain sync still needs to sync 56 weeks, but I want to export my private keys from the bitcoin qt wallet to blockchain.info. Is it possible to do that without waiting for ...
2
votes
2answers
264 views

What is the NTX ID that Mt. Gox refer to in their Feb 17th Statement?

Mt. Gox have released a statement concerning their recent withdrawal problems. In order to launch the new system, we are going through the following steps: Re-indexing the entire ...