Tagged Questions

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'.

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1answer
9 views

How does a blockchain store any data?

I read here that since Bitcoin is a networked ledger, it is a good way to back up data. I would like to know two things: How does a blockchain store 'any' data? I would like to know more about a ...
1
vote
1answer
15 views

How are transactions broadcast to the rest of the network?

If a person sends a transaction to another person, and Bitcoin is a peer-to-peer application, how will the transaction get to the rest of the Bitcoin community? How does everyone have the same ...
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0answers
12 views

How to store 30kb file using Decentralized Blockchain Data Storage on NXT (nxtcoin) by attach messages?

I'm curious to how would one store a 30kb file on the NXT blockchain since the NXT protocol can attach a 1000byte message. My test scenario is storing a 30kb midi file on the nxt blockchain and then ...
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2answers
18 views

Block Chain API for BTC transactions

I want to fetch transactions for an address from the following api: https://blockchain.info/address/$btc_address?format=json The thing is understanding the json returned from the api, I don't ...
4
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1answer
46 views

What are 'pegged' side chains are and how they will be useful for Bitcoin?

What seems to be a very important paper was released this past week (http://www.blockstream.com/sidechains.pdf). It centers around the idea of 'pegged' side chains, and being able to move coins from ...
2
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1answer
30 views

Can side chains or “pegged” chains negatively affect the security of Bitcoin?

Regarding the concept of side chains or "pegged" chains which has been discussed since as early as 2011 and explored in this white paper, how can these negatively affect the security of Bitcoin? ...
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0answers
24 views

Primary lesson about usage and working of bitcoins [on hold]

I was totally unaware about bitcoin.One month back I was surfing on internet and came through a bitcoin site.In that site there were instructions to create bitcoin address to earn bitcoins.I followed ...
2
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1answer
18 views

What does the main_chain value returned by blockchain.info mean?

What does it mean that for bitcoin block to be on the Main Chain? What other chains are there? Is this as opposed to testnet? This is regarding the main_chain value in the blockchain.info api here: ...
2
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1answer
26 views

How to exploit the possibilites of blockchain for proof of authorship?

I want to to create some kind of Proof-of-Authorship mechanism, that's something that many artists had asked before: How can I prove authorship of my work To accomplish my objective I need to deal ...
0
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0answers
18 views

If I want to run the Bitcoin client from another OS, can I direct Bitcoin to an already downloaded Blockchain on another OS' partition?

I have fast internet, and it wouldn't be too much of a struggle just torrenting the bootstrap.dat, but it would make sense to make use of an already existing blockchain and save space and time. I've ...
0
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1answer
31 views

Is it possible for corporate interests to incentivize securing alternate Blockchains instead of Bitcoin's Blockchain?

Is it possible for corporate interests to incentivize securing POW of alternate blockchains instead of Bitcoin's blockchain? Given the large amount of funding and/or "partnerships" announced the last ...
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0answers
10 views

How do I change the default blockchain Database download location for NXT?

I'm testing out the nxt client and was wondering how do i change the default database download location? Its currently downloading to the current folder (nxt_db).
0
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0answers
25 views

How fast is the NXT blockchain growing in 2014?

Is there a place that where I can find out how fast the NXT blockchian is growing? I'm curious because its this year (2014) where a bunch of nxt features came into the scene and was wondering how one ...
0
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0answers
32 views

Blockchain.info Wallet API: How can I send bitcoin without transaction fee

I am using Blockchain.info Wallet API for sending bitcoin. According to the API document, transaction fee must be greater than default fee. I tried to put the fee was 0 but the setting was ignored. ...
0
votes
1answer
22 views

Remove address from sequence in HD wallet

Is there a way to eject an address out of the sequence of an HD wallet? Lets say an address was used for a political donation to a regime in Namibia that may get international condemnation a few ...
3
votes
3answers
67 views

Random numbers using blockchain

How are the block hashes generated? Are they trully 100% random (generated by hardware) or is it pseudo-random (generated by software)? Can i rely on it or any other blockchain data to make a 100% ...
0
votes
1answer
58 views

If all block chain copies get deleted, what would happen?

What would happen if all block chain copies get deleted at one time? At first, all clients would try to get the block chain from other clients, right? But this would fail. Would the "network" then ...
0
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2answers
75 views

Difference between a bitcoin wallet and the blockchain

As the title said, what is the difference between the bitcoin wallet and the bitcoin core, do i have to install both of them to work? Can I just have a bitcoin wallet?
5
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1answer
135 views

What is a soft fork?

When people talk about possible changes to how Bitcoin works they sometimes say a particular change can be implemented as a soft fork. What does that mean? How does this compare to a hard fork?
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2answers
48 views

Can decentralized blockchain technology like bitcoin be used to store medical information? [closed]

For example patients get private key, providers get public key?
1
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1answer
31 views

Blockchain transaction message length limit

When I perform a transaction on the blockchain, I can add a message to the transaction, which will then exist forever in the blockchain. Say for example I wanted to use the blockchain to store ...
6
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4answers
342 views

How to find a specific bitcoin address from all the addresses?

Recently, I found a site that show all the addresses in a huge list, divided in 904625697166532776746648320380374280100293470930272690489102837043110636675 pages. The site's link is ...
0
votes
2answers
35 views

How much binary data (bytes) could I put in a transaction and how?

I know that some people had put text, pdf and images in the blockchain. I wonder which are the limits in order to have a minimum "bytes/btc" value in regarding the blockchain as a permanent database. ...
0
votes
1answer
40 views

Blockchain Parser not working on blockchain generated in regtest mode using bitcoind. Any help?

Has anyone used this blockchain parser for Bitcoin https://code.google.com/p/blockchain/ ? http://codesuppository.blogspot.in/2014/01/a-command-line-interface-for-blockchain.html I tried to parse ...
0
votes
1answer
29 views

Bitcoin-qt and lost local blockchain files

For some reason I've lost all data in my .bitcoin directory except the wallet.dat file. Now bitcoin-qt shows 0 balance, and it's 5 years behind sync. Is this possible to restore coins in this case?
0
votes
1answer
25 views

Local Testnet3, where do the new coins get sent to?

I'm trying to setup a local testnet with multiple nodes. Currently I have three nodes, and their mining powers are almost the same. When I use listaccounts RPC call, all the wallets have 0 coins. ...
0
votes
1answer
23 views

Why do Bitcoin API services offer Block details?

I understand having APIs around addresses and transactions, but I'm less clear why I need to know what's happening with a Block(s). This is to confirm one's transactions? Might someone provide some ...
1
vote
1answer
35 views

Bitcoin testnet: “Bitcoin is downloading blocks…” and other problem

I'm trying to setup a local testnet with multiple nodes. Currently I have three nodes, and their mining powers are almost the same. Things have been quite ok so far, except some problems that I need ...
1
vote
2answers
64 views

Where can I find a chart of the daily supply?

there is the blockchain.info one for total supply but that very low resolution. I really was a graph of the actual new bitcoin mined on the market on a daily basis because it seems like a strangely ...
1
vote
1answer
92 views

Can you switch the method of blockchain download?

I torrented bootstrap.dat and used am using it to populate the blockchain. It is close to being complete, but my server has ran out of room. There is room for one copy but not enough for two. Is it ...
0
votes
1answer
150 views

Best way to anonymize bitcoin transactions?

https://en.bitcoin.it/wiki/Mixing_service How do sites like this work? "Mixing services". I know it can be broken and traced back with coinsuduko but how exactly does it wash your coins. I doubt they ...
2
votes
2answers
67 views

How to get correct block details url with block height on blockchain.info

I need to generate urls to block details page of blockchain.info when I have block height as input but cant find the relationship between block height and the number they are using in the url. Eg: ...
4
votes
1answer
45 views

Can I use Blockchain API to get number of transactions at BTC address?

When I go to blockchain to look at a BTC address I can see a count of the number of transactions that have been sent to that address. So can I use the blockchain API to get this information? I have ...
1
vote
1answer
68 views

What are the equations to convert between bits and difficulty?

If we take transaction hash 0000000000000006770c3806960539ca83a24facbd99ea212f37f2a0e6a5629a for example. The difficulty as a 32 bit float is 50810339.04827648. The difficulty in bits as an unsigned ...
0
votes
0answers
23 views

json RPC Blockchain not Working

I am unable to connect to the Blockchain API, here is the code: $rpc_host = 'rpc.blockchain.info';$rpc_port = '80'; $rpc_user = 'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX'; $rpc_pass = 'PASSWORD'; ...
0
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0answers
25 views

Bitcoind randomly stops downloading the blockchain

I have bitcoind running from a 2 GB CentOS 6 box in order to check balances of addresses. The problem is that it just randomly stops downloading the blockchain sometimes, and I have to use ./bitcoind ...
4
votes
2answers
64 views

Accelerated block generation

According to http://btc.blockr.io/ : Height Block created Transactions Block fee Size (kb) Days destroyed 318525 2 minutes ago 28 0.00370000 8.36 kB 2.00 318524 3 ...
0
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2answers
63 views

How many OP_RETURN transactions in the Blockchain would be too many?

I realize this question may not have an answer and therefore might not be suitable for SE, but I'm very curious about OP_RETURN transactions. OP_RETURN transactions appear to be the accepted ...
4
votes
4answers
195 views

How can I search for transaction text on the blockchain?

Is there a google like search engine which can search for any text that is included with a bitcoin transaction? As I understand it each transaction includes 80 characters of text as well. Update It ...
0
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0answers
59 views

Overview of Blockchain 2.0 smart contracts for the layman?

I have a pretty good understanding of how the Blockchain secures data using hashed inputs of the previous block and being secured by the P2P distributed network. What I'm interested in is a layman ...
0
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0answers
7 views

Can I force the Bitcoin core client to keep the blockchain on another drive instead of AppData/Roaming? [duplicate]

I have been profiling my disk space and found that the blockchain has become pretty big 25GB or so. I would like to force the core client to save the chain on another drive that is much larger. Is ...
0
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1answer
78 views

Lost private keys. Help to recover

I have blockchain wallet but have lost the private keys of it, is tr any way to restore my private keys. Plz help
0
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1answer
62 views

Blockchain command line tools

I was under the assumption that the bitcoind server allowed you to query the blockchain and run commands like bitcoind getbalance on any address. I'm finding out that you may query addresses in your ...
1
vote
1answer
65 views

Unconfirmed Transaction >22 hrs [duplicate]

I realise that this might be a duplicate however I have not actually seen a sufficient answer to the question aside from 'wait'. I submitted a transaction yesterday from a blockchain wallet to a ...
1
vote
1answer
62 views

Tie Breaking in bitcoin transaction

If two nodes broadcast different versions of the next block simultaneously , some nodes may receive one or the other first. In that case, they work on the first one they received but save the other ...
0
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0answers
44 views

Have betsofbitco.in deposits been spent?

I recently noticed http://betsofbitco.in/ went dark. Is there a straight-forward way to guess if any of the outstanding deposits have been spent in the mean time? I guess the coin could get rotated ...
1
vote
2answers
356 views

Where to place Bitcoin bootstrap.dat

I'm sure this has been asked many times before, but I've recently gotten into the whole cryptocurrency thing starting with Dogecoin, and I now want to use Bitcoin as well. I am on Windows 7. I found ...
7
votes
2answers
102 views

How do you create a planet-specific cryptocurrency that will ignore longer block chains from other planets?

I'm sure that cryptocurrencies will play a huge part of the economy across the solar system, when we have colonized many different planets, moons, and asteroids. But there are problems with using a ...
0
votes
1answer
31 views

multiple parties to sign a transaction before being broadcast (or after, but either way be associated with)

Lets say someone was writing a transaction solely to denote the existence of something, or a timestamp, or writing something in OP_RETURN Could that transaction be signed by other addresses, kind of ...
2
votes
1answer
38 views

How frequent are side-chain reorganizations of various lengths?

I'm wondering if anyone has collected statistics on how often reorganizations of side-chains with length 1 happen in comparison with lengths of 2, 3, or more. Related: What is the longest chain ...