texts: What exactly does the "For each input, if the referenced output exists in any other tx in the pool, reject this transaction." tx validation rule mean?

texts:
I am currently following the "tx" messages section of en.bitcoin.it/wiki website, and I need some clarity about the following rule regarding the validity of a transaction:

For each input, if the referenced output exists in any other tx in the pool, reject this transaction.

I don't really understand which of these two interpretations is meant here:

The output referenced by the input must not be referenced by another input of a transaction already in the pool.
The output referenced by the input must not be present in a transaction already in the pool.

Or perhaps it means something else entirely?


texts: My bitcoins are stuck I need help please

texts: Ok so I was transfering bitcoins from my wallet on my phone to a friend's computer wallet and I'm pretty sure his address changed halfway through because his address is no longer the same and the bitcoins are lost now and I'm so confused, the transactions are still unconfirmed but I don't know how to get them back or get them to the right address it's using blockexplorer here's the link to the transactions anyway https://blockexplorer.com/tx/eafacd02739a473a454c73502400eed4d77b0fc6ae0a96752cd2503274f87309


texts: What is the best Lightning implementation to obtain the network graph?

texts:
I want to obtain a fresh snapshot of the Lightning network from my own node. So far I've experimented with Eclair, its API calls allnodes, allchannels, and allupdates give me the information in the following format (examples from testnet).

A node:

{
    "signature": "304502210091f498ae307be653c3dc54954e4e20fcf1a42ff6f0ff7cfe9f1b4367f64349f2022069931b88e1a05cf16ebd08a7272f2249ec47816c9bda51d7b1b4c70b35ed580001",
    "features": "",
    "timestamp": 1543424260,
    "nodeId": "03be1602dd945198ad92b96ed6de85ba41d6c69cc5e81826d5d05a176bf9a38fcd",
    "rgbColor": "#e20f00",
    "alias": "shangod1933e2a-3f17-4",
    "addresses": [
      "54.242.15.59:9735"
    ]
  },

A channel:

{
    "shortChannelId": "1288195x260x0",
    "a": "02ece82b43452154392772d63c0a244f1592f0d29037c88020118889b76851173f",
    "b": "03933884aaf1d6b108397e5efe5c86bcf2d8ca8d2f700eda99db9214fc2712b134"
  },

An update:

{
    "signature": "3045022100fb115950efdeb745d16e79b13be18d01a02c66f2bad0a2050ac157f70e51fe9502201694b2ff817bd5a1bc44488e9732e233f2ca93528df5cbe134ecc2555e7b2a5601",
    "chainHash": "43497fd7f826957108f4a30fd9cec3aeba79972084e90ead01ea330900000000",
    "shortChannelId": "1448407x42x1",
    "timestamp": 1560197957,
    "messageFlags": 1,
    "channelFlags": 0,
    "cltvExpiryDelta": 144,
    "htlcMinimumMsat": 1000,
    "feeBaseMsat": 1000,
    "feeProportionalMillionths": 1,
    "htlcMaximumMsat": 16777215000
  },

Do other implementations (LND, c-lightning) provide the same information (maybe in a different format)? If I want to get the most available information about nodes and channels, should I stick with Eclair or switch to another implementation?


texts:
A rather dumb title, however I have question that I cant get a grip on related to bitcoin:

If the amount of bitcoin is supposed to have an upper limit, what is the incentive to mine in the future if that limit is reached?
If one entity controls more than 50% of the network then the protocol will break down, doesn't the continuous rise in difficulty destine that only one ASIC miner will be left?
Who is it that sets that difficulty level and why then is it  called decentral?
To participate you need the complete blockchain stored locally. How is this supposed to scale when data to store is growing exponentially?

I seems that the system is built to only day just vanish.


texts:
the name miner might come from the fact that it earns profits from block rewards; but a miner also earns profits from transaction fees, and it can choose which transactions to include into a block or not; usually, a miner also offers wallets as an integrated customer service; all of these remind me of a typical stock broker rather than someone working in a mining field;

i am wondering, which types of revenues, block rewards, tx fees or other paid services, provide the most income for a miner during these days;


texts:
I sent $50 worth of bitcoins from coinbase wallet to bittrex wallet but received only a third of it in the bittrex. Could someone please explain if the i will get more bitcoins later or did i just lose it?
This has never happened before as i have done this transfer previously as well.
It shows confirmed on coinbase but it still doesn't show all my bitcoins on bittrex wallet.

EDIT - i just found out that 66% was the fee they charged me. Why is that? They generally charge 0.25% but this is ridiculously high.


texts: Creating a "listunspent" API call using MongoDB

texts:
I used a tutorial online to create my own block explorer (https://www.youtube.com/watch?v=laeV2slJgc8).

In this tutorial, I used "Iquidus" to create the block explorer, which uses MongoDB and Node.js. Now I want to make my own API call that will list all UTXOs for a given address.

Is there a MongoDB query I can just run to get the UTXOs or What would the code even look like to do something like that?

The call I am talking about is the same they have on "https://chainz.cryptoid.info/api.dws":

"unspent becomes available, this API is similar to blockchain.info's, it has a single active parameter in which you can pass multiple addresses separated by '|'. It returns information about unspent outputs of those addresses."

MongoDB is a schema-less database but I managed to get this:

> show collections
addresses
coinstats
markets
peers
richlists
txes
> var col_list = db.addresses.findOne(); for (var col in col_list) { print (col) ; }
_id
a_id
balance
sent
received
txs
__v
> var col_list = db.coinstats.findOne(); for (var col in col_list) {print (col) ; }
_id
coin
last_price
connections
supply
last
count
__v
> var col_list = db.markets.findOne(); for (var col in col_list) {print (col) ; }
_id
market
history
sells
buys
chartdata
__v
> var col_list = db.peers.findOne(); for (var col in col_list) {print (col) ; }
> var col_list = db.richlists.findOne(); for (var col in col_list) {print (col) ; }
_id
coin
balance
received
__v
> var col_list = db.txes.findOne(); for (var col in col_list) {print (col) ; }
_id
txid
blockhash
blockindex
timestamp
total
vout
vin
__v
>

Desired output

{"unspent_outputs":[{"tx_hash":"819d2c6331fecf0bcda79962ed7b66c71b508a4698680b84310f4d2f67203e87","tx_ouput_n":0,"value":100000,"confirmations":63499,"script":"76a9142beec605c9a6512f55fe93ad76753e24fc8579b088ac","addr":"MBuTKxJaHMN3UsRxQqpGRPdA7sCfE1UF7n"},{"tx_hash":"819d2c6331fecf0bcda79962ed7b66c71b508a4698680b84310f4d2f67203e87","tx_ouput_n":1,"value":767048,"confirmations":63499,"script":"76a9142beec605c9a6512f55fe93ad76753e24fc8579b088ac","addr":"MBuTKxJaHMN3UsRxQqpGRPdA7sCfE1UF7n"},{"tx_hash":"7d76cc54c510f1e8f4dd4dbf4d215713245cb3fd7ec1417f852b7d34deee116f","tx_ouput_n":0,"value":1000000000,"confirmations":63439,"script":"76a9142beec605c9a6512f55fe93ad76753e24fc8579b088ac","addr":"MBuTKxJaHMN3UsRxQqpGRPdA7sCfE1UF7n"},{"tx_hash":"03033110cbe81f34c3eede0affd626a135ccea67e783f2beaf02c98ba2e721f3","tx_ouput_n":0,"value":314419,"confirmations":10977,"script":"76a9142beec605c9a6512f55fe93ad76753e24fc8579b088ac","addr":"MBuTKxJaHMN3UsRxQqpGRPdA7sCfE1UF7n"}]}


texts:
I am trying to run a private Bitcoin network for testing.
I tried to run a RegTest network, but I need the addresses to be in the format of the ainnet.
Can I configure the RegTest to run with Mainnet addresses?

Thanks!


texts: Why haven't a large number of cryptocurrencies copied Primecoin's mining algorithm?

texts: According to my understanding, generating an ever-growing list of prime numbers benefits mathematics and society in some mysterious way.  Given this, why have more recently created proof-of-work focused coins largely ignored Primecoin's mining algorithm in favor of Bitcoin's, which yields no epiphenomenal benefits?


texts: get Armory to use an existing blockchain?

texts: I'm trying to set up Armory but it wants to download the whole blockchain.  The thing is I already have the blockchain downloaded on the same machine for bitcoin-qt.  Is there any way to get Armory to use the blockchain I already have, both to save space and avoid waiting for hours?


texts: Can a cold storage bitcoin wallet become obsolete?

texts: Will a cold storage wallet always work?  What happens if the bitcoin protocol is updated? Is there a vulnerability in the protocol that could be changed to create this situation? Where is this formally documented?


texts:
since some answers seem to be outdated, I ask now explicit for version 0.8.5 of the official BitcoinQT-client.

I want to save my wallet to paper and hide them in a safe - could you tell me if following points look valid?

This topic seems really complex, I dont know why there is not an easy option like "Export wallet to pdf"...

Ok so here we go:

1) I would like to export my private keys to textfile?
(How does it work?) I only see how it works for one single private/public key-pair?

2) Print it out and hide it in safe

3) When I do a transaction or receive something, i should print out again all private keys, because otherwise something can be lost?

Thanks!


texts: How many shares need to be mined before a block is released?

texts:
How many shares need to be processed on average before a block is found?

I know that "luck" can be a huge factor which is why it's not quite as simple as that.

I ask because I'm starting my own pool (www.btcpoolman.com). I only have three people on it at the moment, but we've mined about 100K shares in the past week or so. Assuming I sustain this, how long will it be before I will get a block?

I found http://www.bitcoinx.com/profit/ yesterday, which says that it'll take one year and 138 days to find a block based on 1.2 GHash/s (which is roughly what I do when soloing).

Failing that, what should I do if I'm currently mining at the above rate?


texts: Can a single wallet generate (and use) both SegWit and non-SegWit addresses?

texts:
Is a Segwit wallet able to generate and use non-Segwit addresses?
I'm using Bitpay's Bitcore to create wallets and generate new addresses for the users of my platform. I'm also using Bitcore-wallet-client to sign transactions.
My users have legacy wallets right now. I intend to migrate their wallets to native Segwit, but they will also need legacy addresses so that they can receive coins from anywhere. (right?)
Is it possible to have only one wallet per user, generating both types of addresses, or will I have to manage two wallets per user?
And if I have to manage two wallets per user, utxos from one wallet won't be available to the other, obviously. What's the best way to deal with their 'split balance'? Should I orient users to send all their coins to the bc1 address of the new Segwit wallet? But then, whenever they receive funds in their legacy addresses, they'd have to transfer again to the bc1 address in order to make Segwit transactions. It makes no sense - or does it? What am I missing?


texts:
Just read this: https://bitcoin.stackexchange.com/a/1715/

What is the process to generate compressed pub keys via ECDSA?


texts:
The block header contains a number of things, among them the Merkle root hash. Wouldn't this mean that every time a new transaction is added to the block (before its mined), that all nonces previously attempted need to be tried yet again?

Wouldn't this discourage miners from adding transactions to the block if they have to hash everything with nonces again?

Also, is it possible that no nonces could produce a valid successful/winning hash?


texts: How do I start mining for bitcoin and what is the best bitcoin miner to get me started?

texts: So I am new and I was wondering about mining. So it is not as simple as buying a bitcoin miner on eBay for 400$ and then setting up so then I can jus mine a bitcoin worth 30,000$? And then how does it work.


texts: How to Use TransactionBuilder in NBitcoin

texts:
I have used this code. It returns a success, but does not send bitcoin.

    var txRepo = new NoSqlTransactionRepository();

    // Let’s me introduce you, Alice, Bob, Satoshi, and Nico with their private keys.
    BitcoinSecret alice = new BitcoinSecret("");
    BitcoinSecret satoshi = new BitcoinSecret("");

    var network = alice.Network;

    Transaction aliceFunding = new Transaction()
    {
        Outputs =
            {
                new TxOut("0.0009", alice.PrivateKey.PubKey)
            }
    };
    Coin[] aliceCoins = aliceFunding
                            .Outputs
                            .Select((o, i) => new Coin(new OutPoint(aliceFunding.GetHash(), i), o))
                            .ToArray();

    //Now Alice wants to send 1.00 BTC to Satoshi, with 0.001 BTC fees for miners.
    var txBuilder = new TransactionBuilder();
    var tx = txBuilder
        .AddCoins(aliceCoins)
        .AddKeys(alice.PrivateKey)
        .Send(satoshi.GetAddress(), "0.0002")
        .SendFees("0.0001")
        .SetChange(alice.GetAddress())
        .BuildTransaction(true);

    txRepo.Put(tx.GetHash(), tx);
    //Assert(txBuilder.Verify(tx)); //check fully signed
    Literal1.Text = tx.GetHash().ToString();

    var client = new QBitNinjaClient(network);
    BroadcastResponse broadcastResponse = client.Broadcast(tx).Result;

    if (!broadcastResponse.Success)
    {
        Literal1.Text = (string.Format("ErrorCode: {0}", broadcastResponse.Error.ErrorCode)).ToString();
        //Literal2.Text = ("Error message: " + broadcastResponse.Error.Reason).ToString();
    }
    else
    {
        Literal1.Text = ("Success! You can check out the hash of the transaction in any block explorer:").ToString();
        //Literal2.Text = (transaction.GetHash()).ToString();
    }


texts: Are there any studies into the size of the blockchain scaling over time?

texts:
After watching some of one of the 28c3 talks, It got me thinking about just how scalable Bitcoin really is.

With the size of the blockchain currently, given the number of transactions/users, will the size of the blockchain be manageable as Bitcoin adoption increases?

As an example (no answers about "this will never happen" please), if Bitcoin was as large as a company like VISA, hundreds/thousands of megabytes would have to be transmitted over the network daily and stored in the blockchain. This is not including other things being stored in the blockchain that essentially shouldn't be (Eligius putting prayers in the blockchain for example).

This would mean that most casual users would need to use a thin client as storing the blockchain and keeping it up to date would require super fast internet and masses of hard drive space. (imagine Visa's 92 billion transactions per year)

Are there any studies into the scalability of the blockchain? Or is the assumption that technology will be so advanced by the time of this ever occurring that it will not be an issue? (which doesn't sound like the greatest conclusion in my opinion)

Also, quoting the wiki:

  At very high transaction rates each block can be over a gigabyte in size. These blocks must be stored somewhere. Whilst for speed it'd be ideal to store the block chain entirely in RAM, for cheapness storing only the hot parts in RAM and the rest on disk is the way to go. A 3 terabyte hard disk costs less than $200 today and will be cheaper still in future, so you'd need one such disk for every 21 days of operation (at 1gb per block).

3 TB every 21 days? 52 TB a year for the blockchain alone? Is that REALLY scalable?


texts: Why does some transactions have an excessive number of receiving addresses?

texts:
Such as this transaction: 92088fe6b9d9c9db84d26481b80104f8ca566649a656b7aa3e67432b346cbf1c, which has over 5000 receiving addresses.

It is unlikely that someone would send money to that many business partners at once, let along each individual output is quite small. If that is done for privacy protection purpose, over 5000 receiving addresses is too excessive.


texts: Signature on transactions with multiple inputs

texts:
My question is that, suppose there is a txn tx(k) paid from user u to v, that refers two txns tx(i) and tx(j) as it's inputs. Also, both these inputs are meant for different public keys of u, say, Pk1(u) and Pk2(u).

How does u sign tx(k) for v, i.e. how does she convince v that she owns both of those public keys? Does she sign tx(k) with both Sk1(u) and Sk2(u)?
Thank you.


texts:
The Ven FAQ states that Ven is a basket of currencies, but how is it determined? Is it done privately or in the style of a committee? What trade offs are there in relation to Bitcoin?

Links: official site, wikipedia entry


texts: How to find the shortest unused FirstBits?

texts: I am interested in generating a bitcoin address with the shortest possible FirstBits. By random trial and error I found that 1ijj1 is untaken. Is there a way to find the shortest possible untaken FirstBits? (So I can generate it using vanitygen)


texts: How do mining pools fetch and retrieve blockchain data? How could one start their own?

texts:
I was just wondering how the various cryptocurrency mining pools are fetching the live transaction data, such as merkle trees, block hashes, etc. I am new to mining, but a great programmer, so I had implemented about as fast of a bitcoin miner I could get on my old 2012 iMac, which can run at almost 2MH/s (faster one newer processors, but it's still a CPU, so, now much better I can get). However, I'd like to know how the hosts of these large pools are actually submitting and retrieving the data to/from the connected miners. This is because my hardware is so old and slow that most pools don't even recognize my worker due to the great discrepancy between my hardware and that of others. I'm not looking to make some great amount of money, but just a way to have fun mining without being rejected due to considerably low hash rate.
Thanks.


texts: Is it safe/wise to buy bitcoins with a credit card?

texts: I'd like to buy bitcoins with a credit card or should I use my debit card?


texts: BTC sent to multisig address, but no info about this in bitcoin core (listsinceblock, getwalletinfo, listunspent)

texts:
I sent BTCs (testnet) to multisig address:

address:     2N8yzozJh1DFgrnND7TbSbuSQ1NPA8byQDu
transaction: 2453fe904b74acbbf541f98d2d5a1d7a509457a3df10bf38d0c3cb9326734dcd

But my bitcoin core does not return any info about this:

listsinceblock does not print this transaction
getwalletinfo returns balance 0.00000000
listunspent prints nothing

Why is that? Why is this different from regular addresses? How to know that I received BTC on my multisig address?
Here are my test wallet addresses:
./bitcoin-cli -conf=/home/bitcoin/conf/bitcoin.conf getaddressesbylabel ""
{
  "mmqFbnqtWdXU17SkSfTWAyXMLbPRzxZRrV": {
    "purpose": "receive"
  },
  "2N8yzozJh1DFgrnND7TbSbuSQ1NPA8byQDu": {
    "purpose": "send"
  }
}

Is this because of the purpose of the multisig address?

Edit 1
I created this multisig address using createmultisig as I saw this in multiple tutorials. Then I realized, that my wallet does not know anything about this address, so I called addmultisigaddress with the same parameters. Here is the command:
./bitcoin-cli addmultisigaddress 2 '''
      [
        "'027f27ef1c543fdcbf4804dd79a21fe61e9d6d367cd7e13dffc58bffbd11c62732'",
        "'0362a556ffd4f6592604961d909b913a15872b605956fafb8de00e7aeb9b6ae0db'",
        "'028568c9ffc5f6e975104aa520c167bbeff80dd8a8f29905b052230fc8e15ba19d'"
      ]''' "" legacy

These public keys are from three separate test wallets.


texts:
I'm running bitcoind on a remote server (so I can only use the "headless" version). However, the client is not connecting to the bitcoin network. The "getinfo" command shows "connections: 0". I have also been keeping an eye on the blocks folder and there is no change there (when running bitcoin on the local machine, I can see files being created and updated there).

Here's what my bitcoin.conf looks like:

daemon=1
server=1
rpcuser=<redacted>
rpcpassword=<redacted>
rpcport=<redacted>
rpctimeout=60

Port 8333 is open for UDP traffic in my firewall and I have used an external port scanner to verify that it is open. However, I understand that that's not actually necessary for outgoing connections. I've also checked that my date / time is synchronized (this was suggested in some of the threads that I found on this topic).

What are other possibilities?


texts: What's to stop someone from making a ton of mining nodes as an attack method?

texts:
My understanding is that if two miners make a block by completing a hash at the same time, it is then up to the miners to decide which is going to be 'accepted' by vote of which block reaches 51% of the votes first.

What's to stop someone from making a ton of nodes just so that they can get an advantage if this situation arises for himself? (Another node finished a block at about the same time as me, so I unleash my army of nodes to all vote for the block that I made)


texts: Public Key + Private Key enough to backup?

texts:
I invested in bitcoins and unfortunately I have problems to understand the system. Perhaps you can answer me the following questions?

1.a) I know my public and my private key. Do I still have to backup my wallet.dat?

1b) If I need the wallet.dat: There is no point in saving my public and private key, if I need the wallet.dat anyways, right?

If I secure my wallet.dat with a strong password, can I put the wallet.dat just on dropbox and send it to a few friends or do I have to keep the file more private?
Is the decripting function of Bitcoin-QT enough?
Am I okay with these actionsteps:
Encrypting my wallet with Bitcoin-QT and writing my password on paper
Writing my public key and private key on paper
Sending the bitcoins from mtgox to my public address
Using the backup option of Bitcoin-QT and send the backup to dropbox + a friend I trust

Please let me know if I need more steps or I can take a step out.

Thanks!


texts: Mining Hardware lifespan is less than a year?

texts:
I have been exploring mining hardware at http://mining.thegenesisblock.com today.  No matter what hardware I look at, all of them are making no profit by Oct 2014.

How is this a good purchase?  I assume the answer is that if you spend 5K on hardware and electricity and make 60K back in bitcoin in a years time, then you can consider it a good purchase (even though the hardware is now losing money).

Also, how is this model sustainable?  Will new hardware be developed fast enough to continue mining past the middle of 2014?  Am I reading too much into that prediction tool?


texts: One of my colleagues is trying to use bitcoinjs with TestNet, but apparently it doesn't like TestNet headers, so it doesn't work. Is there any way to make to use bitcoinjs with TestNet? Is there some specific configuration needed?


texts: In which circumstances is the identity of a miner known?

texts:
I started playing with the Blockchain real-time API and noticed that when new blocks were created, they often (systematically?) included a foundBy field. For instance, block with height 446731 (index 1442483) has the following foundBy information:

{
    "ip": "0.0.0.0",
    "link": "http://bitfury.com/",
    "description": "BitFury",
    "time": 1483612060
}

I have never mined bitcoins; do all miners have to disclose their identity? Obviously, the identity of the miner of block with height 0 is unknown. Is the foundBy field a new feature of recently-mined blocks?


texts: Blockchain Receive API - custom Parameters

texts:
I am trying to get variables back from the callback URL, but I can't figure out how to add custom parameters correctly. This is how I have them written right now:

$newAddy = json_decode(file_get_contents("https://blockchain.info/merchant/$ID/new_address?password=$PW&funding_id=$funding_id"),true);
$parseAddy = $newAddy[address];

$funding_id is the extra one that I want to add. Any suggestions?


texts:
How does "Sign Message" option in the Bitcoin QT client work? I can't find any description or documentation of it.

Do I have to use this option to sign some message when I receive bitcoins? If so, how do I do that and what should I write?

This is how it looks (Sorry for danish client language):


texts: Confusion over BTC value - MtGox vs CoinDesk

texts:
I'm trying to find the current value of BTC.

If I go to MtGox the ticker at the top says the average price is about $950 but at CoinDesk.com the daily high, low etc are all $100 cheaper...

Both are in USD.

The CoinDesk seems to be the accurate one but why are the MtGox values so much higher?


texts: Can miners choose which transactions to mine?

texts: I'm curious if miners can choose which transactions to mine?  I know that there are limits to the minimum size of a transaction fee (around 5400 satoshis) but I'm wondering if miners can ignore those limits for certain transactions.  For example, if I gave a mining pool a list of addresses and offered an incentive to them to mine them even though the transaction was non-standard, could they do it?


texts: Is there any way I can find out how many Bitcoins existed at a certain point in time?  Are there charts where I could, for example, see how many Bitcoins were in existence in 2011, so I could compare to the quantity existing today or something as such?


texts: How to cash out E*Trade stocks (transfer funds from US to the EU) with Bitcoins?

texts:
My company has an employee stock purchase plan with etrade.com, but as I'm in Europe, I thought I could sell the stocks and save the bank transfer fees by using bitcoins.

You can sell the stocks online on NASDAQ though, but even to just place the order they ask for an bank account. So I either have to transfer to EU, paying the fee, or to an US account. As I don't have one, could I simply transfer directly to an Bitcoin exchange?


texts: Why is my phone app wallet showing true balance and my web wallet showing 0 balance

texts: I downloaded my wallet app to my phone my online wallet shows 0 balance my phone app shows true balance why isnt my online wallet showing same balance as phone


texts: If I make a lot of little transactions, sending and receiving various odd small amounts (like 0.00201, 0.00319), does this make lots of little dust bits in my wallet?


texts: Do i have to delete/clear anything in Firefox after creating offline keys using Bitaddress?

texts: If i use Bitaddress in Firefox offline to create key pairs, will any info remain in Firefox/anywhere else that i will have to delete  - i mean, if i then use that Firefox to connect to the internet after making the keypairs, could somebody potentially obtain any of the keypair info?


texts:
I made transfer by accident from my bitcash to my bitcoin address instead of bitcash to bitcash, and it's up in the cloud but I cannot claim it. I sent bitcash coins from CEX.IO wallet to my bitcoin account in Trezor.

The transaction went thru and now it's in a cloud on my account but because my account is bitcoin its not possible to get bitcash.

Does anyone know how I can release the money?


texts: Can I recover a 12 word passphrase if I only have 11 words

texts: I have crypto wallet with a 12 word passphrase. I have written down the words incorrectly and omitted a word. Are there methods of recovering the 12th word. I have access to the wallet account but cannot carry out transactions without the passphrase. Any advice would be appreciated


texts: Adroid Blockchain wallet ver 4.0.12 recovery

texts:
Just repaired my old Android phone, with Blockchain wallet version 4.0.12. It is asking for either the four digit PIN or the password, which I have both forgotten.
Is there any way to recover this now seven years old wallet?


texts: Python library for Multisignature HD wallets

texts: Is there is any python library is available that allow creation of Multisignature HD wallets ?


texts: If SHA256 and/or RIPEMD-160 were broken, would all bitcoin addresses be compromised?

texts:
If not, what else would be needed to steal all funds from all people and completely break bitcoin?

I bet some will say ECSDA gives bitcoin an additional layer of protection. I counter this by saying ECSDA is dependent on a hash function such as SHA256. So I will ask this as well: What kind of ECSDA does bitcoin use and would it still be protected if SHA256 were broken?

Yes, I know I am illustrating an unlikely scenario but I still believe we should know what will happen.

If you want to mention other hash functions in relation to SHA256, you can. Feel free to explain how RIPEMD-160 would keep bitcoin safe in case of a SHA256 exploit.


texts: Does using Ripple to accept Bitcoin reduce risk of Bitcoin fraud?

texts: Does Ripple reduce the risk of double-spending, or other types of issues that may crop up when using Bitcoin natively?


texts: Why does Bitcoin send the "change" to a different address?

texts:
For example I have an address (A) with 20 BTC and send 9 BTC to address (B).  Bitcoin will create a "change" portion of the transaction where the remaining 11 BTC goes to address (C).

Why not send the change back to A?

Instead of:

Initial balance:
A: 20 BTC
B: 0 BTC
C: 0 BTC

Transaction Pair:
A -> B 9 BTC
A -> C 11 BTC

End result
A: 0 BTC
B: 9 BTC
C: 11 BTC

Why not?

Initial balance:
A: 20 BTC
B: 0 BTC

Transaction Pair:
A -> B 9 BTC
A -> A 11 BTC

End result
A: 11 BTC
B: 9 BTC


texts: How to withdraw or transfer to bank account

texts: I have bitcoin and i want to sell or withdraw to get the amount to Indian bank or Paypal. Is there any way to get the equal amount for bitcoin. If yes and how?


texts: Webistes like https://miningpoolstats.stream/ must communicate with the pools somehow. What protocol do they use to retrieve information such as the pool's hashrate and what blocks have been mined by that pool? If I make my own pool what is the necessary API to expose this information?


texts: Bitcoin transaction has been unconfirmed for over 24 hours... What should I do?

texts:
I'm pretty new to Bitcoin and although the technology is pretty exciting, I feel as though the sluggish confirmation times are letting it down...

On 18th December I instructed a Bitcoin transaction (5314fb75a5d08caf563cd6f6aaf40f448e9a9c6e0ba6affa499accd3534b97f6), admittedly with a pretty low fee, but I still wasn't expecting it to take days to get confirmed... Will this soon be dropped from the mempool or is there a way I can accelerate the transaction confirmation process?

Yours,
citygent


texts: How can I get my node listed on Blockchain.info's connected nodes list?

texts: We are running bitcoind on our server and its blockchain is synchronized with the network. Do we automatically become a node and get listed on http://blockchain.info/connected-nodes, or is there something we have to do to be seen by the network?


texts: How to check if raw transaction is signed?


texts: ripemd160(sha256(publickey)) - Where am I going wrong?

texts:
(Note: I'm using http://www.royalforkblog.com/2014/08/11/graphical-address-generator/ (use "bitcoin" as the phrase for generating the private key)

I'm trying to take the first step in going from a publickey to an address.

For example, if this is my public key:

publickey = 02218AD6CDC632E7AE7D04472374311CEBBBBF0AB540D2D08C3400BB844C654231

This should be the result of the next step:

ripemd160(sha256(publickey)) = 5238C71458E464D9FF90299ABCA4A1D7B9CB76AB

However, when I try to do this in python, I fail to get the same result:

>>> hashlib.new('sha256', '02218AD6CDC632E7AE7D04472374311CEBBBBF0AB540D2D08C3400BB844C654231').hexdigest()
'6e28eefe40e5855ed8cdf0599ec12e52f73a5b222c84ba957b4dcdd2d8a9cf2a'

>>> hashlib.new('ripemd160', '6e28eefe40e5855ed8cdf0599ec12e52f73a5b222c84ba957b4dcdd2d8a9cf2a').hexdigest()
'e607ff4fa71ef33ca357415e3d2f781c4cedacc3'

Where am I going wrong when using sha256 and ripemd160 in my python code?


texts:
I am trying to understand what values I am being asked for in the settings.json to install the block explorer for Iquidus. I know how to get the genesis block as I have hard coded it when I did a fork to create a new altcoin, however, I am unsure how to get the genesis_tx. I know you can convert it from the genesis block but I am unsure how?

"genesis": {
"genesis_tx": " ",
"genesis_block": " "}

In terms of the API settings, they are asking for an address, blockindex, blockhash, and txhash. The blockindex can be any value within your block height... so do I pick just any one value for the index with the corresponding address in the transaction list? Also, how do I get the txhash and the blockhash? These values to my understanding are subject to change and I know they are stored in the blockchain... does anyone know how I can retrieve this information?

"api": {
"blockindex": " ",
"blockhash": " ",
"txhash": " ",
"address": " "
},

I appreciate your time and consideration.


texts: Is it possible to get the public key from a transaction input that is a 'pay to public key' output?

texts:
I am looking to be able to calculate the public key from the transaction input.  The input is from a 'pay to public key' output.
Can the public key of the input be generated from just the signature and the transaction that the input is in?


texts: I had someone offer to mine bitcoin for me, I am a beginner

texts: I had someone offer to mine bitcoin for me. I pay for the bitcoin on cash app and he mines it for me. With messaging him I started to feel like he didn't really know what he was talking about when telling me to sign up for cash app and coinbase. I followed what he said but during signing up on the 2 sites but it was like he didn't know what he was talking about during the time I had to wait for both account to be verified with 2 small cents deposits into my bank account. But he was telling me miss information on what to do an it didn't make any sense. Cause the sites were basically saying I can't move forward until i enter in the 2 amounts. But had to screenshot the pages to show what they said and had to write it all out for him exactly how it showed on the sight. and after a few minutes he finally understood me. But it feel like he didn't even know how to sign up process went which is suspicious to me an I don't want to get caught in a scam


texts: What are the script size limitations according to consensus rules and are they enforced on TestNet?

texts:
I'm trying to figure out the limitations that scripts have regarding their size, limits that would make a script invalid (ignoring standardness). According to this question and also these lines of code in bitcoin core's source code 1 2 3 it appears that the following rules are in place:

Maximum script size = 10,000
Maximum data size to be pushed to the stack = 520

To test these rules I made a bunch of transactions on TestNet, all of which breaking some rule and were included in blocks (all sent from n3eynMTEiGgPTuoKPApnRjE9pAuaAk3gkB)? Example:
Tx ID: 88bac1e84c235aa0418345bf430fb43b336875974b6e87dc958de196f9222c35
PubkeyScript length=0xfd1527=10,005 script=4d11275b2c...394e75orPush_10001_byte<5b2c...394e> OP_DROP
As you can see the length of the script is already 10,005 > 10,000 and the first data push is 10,001 > 520. In other words I broke both rules.
Also as far as I know the "consensus" rules are exactly the same on TestNet (with one exception: difficulty adjustment), is that correct? So how is this transactions valid?


texts: Monitor a bunch of addresses for deposits

texts:
I have a situation where I create one address per user through GetNewAddress(User.Id)

So, in the end, I have a lot of addresses to monitor, to see if any user has deposited money.

I can do something like this:

foreach (var User in Users)
{
  var T = GetReceivedByAccount(User.Id);
  .. do something if money arrived
}

Wait 30 seconds and repeat...

But I'm guessing it's not the most efficient.

Is there a better way to do this?

Or can I get all transactions within a specific range in the wallet and then parse them by account?

Sorry if the question seems basic, I'm extremely new to this.. got some code running for the first time something like 16 hours ago :)


texts:
I keep seeing this everywhere, but it seems impossible to search. What does Th stand for? What does it mean? How do you calculate the Th?

For example, "The 13.5 TH/s is $2773.28 US". What does that even mean?


texts: Has the BitForce Bitcoin Miner be connected to a PC all the time?

texts: When the BitForce Bitcoin Miner is mining, does it have to be connected to a PC all the time?


texts: A Simple Question: Which blockchain (or ledger) do we query as a client?

texts:
As far as I know, every full node has a copy of the ledger (or its view) stored locally.

A Generic Question: Which blockchain (ledger) do we query as a client?

In my question query is a generic term, it can be to look up, check a transaction etc.

Do we need to query multiple full nodes to get a common view of the nodes?

The following questions are also related to the above question.

Question: Is there one (public) ledger built from the common view of the full nodes?

If the answer to the 2nd question is: no, then why don't we build one unique ledger which is the common view of the majority of the full nodes in the network?

A More Specific Question: If we don't have one ledger, then how do we (as a client) realize that our transaction has got enough confirmation? Do we need to ask many full nodes to realize that?


texts:
When I try to start bitcoind on Centos 5.8 I immediately receive the following error:

bitcoind: /usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.11' not found (required by bitcoind)
bitcoind: /usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by bitcoind)
bitcoind: /lib/libc.so.6: version `GLIBC_2.7' not found (required by bitcoind)

This is the version of glibc I have:

$ strings /usr/lib/libstdc++.so.6|grep GLIBCXX
GLIBCXX_3.4
GLIBCXX_3.4.1
GLIBCXX_3.4.2
GLIBCXX_3.4.3
GLIBCXX_3.4.4
GLIBCXX_3.4.5
GLIBCXX_3.4.6
GLIBCXX_3.4.7
GLIBCXX_3.4.8
GLIBCXX_FORCE_NEW

About my operating system:

OS: CentOS release 5.8 (Final) i686
Glibc version: glibc-2.5-123
libstdc++ version: libstdc++-4.1.2-55.el5


texts:
Let's say, that 20 years ahead, Bitcoins crypto is not considered secure anymore. More precisely the key length is to short for it to be safe. Be it the HASH or private/public key. What would our options be?
Could we simply increase the keylength for the wallets and make it mandatory? Would that be a hard fork?
Or could we just use a soft fork and advise users to switch to a new more secure wallet?


texts: How to allocate hash power to an instance of bitcoind?

texts:
I'm not sure if those questions were asked this way before but ...:

Is it possible to allocate CPU resources/hash power to an instance of bitcoind run on regtest?If yes, how?
Assuming I'm going to run 100 nodes on regtest, how can I run one node with 20% of total hashing power?

Is CPU allocation hardcoded? If yes, where in the code?

If not possible by Bitcoin source code, is there a way to allocate CPU to a daemon, in general?

By the way: I'm using Bitcoin Core 0.10.0.


texts: Separating user accounts in a wallet for a large scale web app

texts:
I'm planning to implement a web platform that maintains user wallet accounts and generally acts as a web wallet. They can deposit, withdraw and transfer coins.The number of accounts should be in magnitude of thousands. I'm considering the implementation options for simulating many different web wallets inside several factual wallets. I wonder how existing services do it?

I'm aware of the following options for the implementaiton:

Using accounts inside wallet. Pros: wallet supports commands for checking ballance, sending from account etc. Cons:  still spends coins from general wallet, so hard to keep track of; Is deprecated; Complicated to do backups
Using separate private keys for each user. Not sure how to do it.
Keeping track of ballances and transactions inside proprietary system. Pros: no problems related to option nr. 1; Cons: Probably a hell to maintain, not even sure how to implement it;

Id love if someone could give me some advice and or share experience. What is the best option? Is there anything else I'm not considering?


texts: P2WSH, witness_v0_scripthash: how to derive an address

texts:
Is there an address associated with P2WSH scripts?
for testnet txid =6717c8971dccbf826790efc16fb357f1e225fed3448247b8556c9f13a6c0ce42, i get:

"vout": [
    {
      "value": 0.05994165,
      "n": 0,
      "scriptPubKey": {
        "asm": "0 43aac20a116e09ea4f7914be1c55e4c17aa600b7",
        "hex": "001443aac20a116e09ea4f7914be1c55e4c17aa600b7",
        "type": "witness_v0_keyhash"
      }
    }
  ]

Is there no address associated with this?


texts:
I am new to block chain technology. I am struggling to understand below concepts:

What if my transaction is not picked by the miners and what is the criteria for miners to pick? How can I rely on blockchain to settle/do fund transfer if it is not getting picked?
Are block chains closed distributed networks? I mean, does each company runs its own blockchain. Do I need to register multiple blockchains and pay fees.
To do fund transfer via blockchain,do I need to publish my account balance in public ledger?If yes then where is confidentiality...


texts: How can I generate a private key to spend the bitcoin of a watch only addresses that is in the imported addresses of blockchain.info?


texts: GHOST can provide higher transaction throughput by minimized block interval, but community people seldom mention it. What's wrong with GHOST?


texts: Does mining without a realistic chance of solving a block provide any benefit to the network?

texts:
Okay, before anyone votes to close this as a duplicate, I would like you to hear me out.

Since I began using Bitcoin, I always thought about miners as the people that effectively "host" the bitcoin network as if it were a website. I know this isn't entirely true, but its the analogy i've been using for a while.

What I want to know is if I mine Bitcoins on my mid 2011 iMac with the sole intention of helping the bitcoin network, will I be providing any real benefit to the network or will I just be fruitlessly trying to solve problems when the bigger, faster, mining-dedicated computers will ultimately beat me to it?

EDIT: Also, as an extension of my question above, could I be one of those miners that tweaks he software and only processes transactions with no fees to provide a greater benefit or would this approach still cause me to get out-hashed by bigger, better computers?


texts: lncli pendingchannels output: difference between `pending_closing_channels` and `waiting_close_channels`

texts:
When plotting lncli pendingchannels, two of the outputs are oddly similar:

pending_closing_channels and waiting_close_channels. I have only seen my closed channels either as the output closedchannels or as waiting_close_channels. I suppose pending_closing_channels refer to the step previous of negotiation for cooperative close? or is it after, during the amount of confirmations needed to wait?


texts: Get uncompressed public key from compressed form

texts:
A similar question has an answer in Python which links to the bitcointalk forum:

How can I get the uncompressed public key from the compressed public key in openssl?
https://bitcointalk.org/index.php?topic=644919.msg7205689#msg7205689

But I'd like to know how a Java program can be written for the same conversion? I noticed that Java uses the byte data type and I'm unable to understand how to operate on values.


texts: does 24-word recovery seed recover just bitcoins or all coins?

texts:
I keep Bitcoins, Bitcoin Cash, Bitcoin Gold, Ethereum (via My Ethereum Wallet) and Litecoins on a Trezor.

Question 1:  In the event that my Trezor is lost or destroyed, will my 24 word recovery seed restore my access to just the Bitcoins, or will it recover the other coins as well?

Question 2: If the answer to Question 1 is "just the Bitcoins", then what should I be doing to preserve my access to the other coins in the event of a lost Trezor?   Is there some way to  display my private keys and copy them down on paper? Or something else I should do?


texts: Generating differnet addresses from same public key?

texts:
There's a gap in my understanding regarding the generation, via hashing, of bitcoin addresses. (I'm quoting from Antonoplous  below for convenience, but I have consulted multiple other sources.)

According to Antonpolous:

  "The bitcoin address is derived from the public key through the use of
  one-way cryptographic hashing. (Antonpolous, 2014:71)"

My understanding of public keys is that they do not change once generated from a private key (via ECDSA multiplication):

  "Because the generator point is always the same for all bitcoin users,
  a private key k multiplied with G will always result in the same
  public key K.(Antonpolous, 2014:68)"

Best practice regarding bitcoin addresses recommends that:

  "a unique address should be used for each transaction. Most Bitcoin
  software and websites will help with this by generating a brand new
  address each time you create an invoice or payment request.
  (Antonpolous, 2014:188)"

I understand that performing a hash function on the same data will always produce the same result (digest):

  "For any specific input, the resulting hash will always be the same
  and can be easily calculated and verified by anyone implementing the
  same hash algorithm." (Antonpolous, 2014:188).

Given all of the above, my question is, how can different addresses be generated from the same, unchanging input, namely the public key?

Is it the double-hashing (SHA256 + RIPEMD160)? Is it the address pool? Is it due to deterministic wallets? The answer is probably simple and staring me in the face, but I can't see it. Thanks for any clarification.


texts: How to reduce disk-space requirements of Bitcoin Core wallet?

texts:
I want to install Bitcoin Core wallet on my computer, but his blockchain is too big (more 230 Gb).

How to reduce Bitcoin Core wallet?


texts: Transaction and Node Proximity Questions

texts:
Say I am a node (M1) in the bitcoin network who wishes to spend some set of bitcoins (T). M1 selects address (A1) with an associated node (M2) that he wishes to transact with and uses some process (F) involving T's private key to sign over T to A1 to be controlled by M2.

My question is how does T get broadcast to the bitcoin network? What model does the software enforce to announce a transaction has occurred? How is this message relayed and what kind of bandwidth does the relay require? Do all nodes reach participate in the transaction relay or just some? How does a miner decide to verify transaction T during his block solution hunt? How many transactions are considered to be a minimum for a block and how many are considered to be a maximum? And finally how long does a miner wait to fill his transaction queue for a given block solution hunt?


texts: Exchanges whose websites use EV SSL certs?

texts:
What are all the Bitcoin exchanges whose websites have an Extended Validation (EV) SSL cert?

EV certs appear green in Firefox. This is what Circle's looks like:

The only exchanges that have EV certs that I know of are:

Coinbase
Circle

BlockChain.info also has one.

Are there others?


texts:
I find on Internet interested article.
How I understand the raw transaction can be created simpler without fundrawtransaction.

bitcoin-cli listunspent [misconf=1] [max_number_confirmation=99999999] '''["<wallet_address>"]'''
bitcoin-cli createrawtransaction
'[{
"txid" : "<txid_of_selected_block>",
"vout" :
}]'
'{"<recipient_address>": <amount_to_send>, "<sender_address>": <amount_change>}'
bitcoin-cli signrawtransaction <hex_createrawtransaction>
bitcoin-cli sendrawtransaction <hex_signrawtransaction>

That's all and without fundrawtransaction.
And I don't understand why fundrawtransaction do need? And what is the difference between "with" and "without"?
I'm a newbie and I not sure I right understand what do mean inputs and outputs and possibly so I can't understand what mean fundrawtransaction?
Please, more examples and more simple speech. Thanks.


texts: MMCFE Not Reporting Stats from pushpool/wallet

texts:
I spent the last two days setting up a Litecoin Mining Pool and from what I can tell, absolutely everything is setup and working correctly. However, after creating a new worker and connecting to it, I have noticed that the stats on the website never update.

I have included my pushpool configuration below, but I am at a loss as to where the issue might be?

[root@test sbin]# vi server.json
{
        # network ports
        "listen" : [
                # binary protocol (default), port 8336
                { "port" : 8336 },

                # HTTP JSON-RPC protocol, port 8337
                { "port" : 8337, "protocol" : "http-json" },

                # HTTP JSON-RPC protocol, port 8339,
                # with trusted proxy appserver.example.com forwarding
                # requests to us
                #{ "port" : 8339, "protocol" : "http-json",
                #  "proxy" : "appserver.example.com" },

                # binary protocol, localhost-only port 8338
                { "host" : "127.0.0.1", "port" : 8338, "protocol" : "binary" }
        ],

        # database settings
        "database" : {
                "engine" : "mysql",

                # 'host' defaults to localhost, if not specified
                "host" : "localhost",

                # 'port' uses proper default port for the DB engine,
                # if not specified
                "port" : 3306,

                "name" : "mmcfe",
                "username" : "user",
                "password" : "pass",

                "stmt.pwdb" :
                  "SELECT password FROM pool_worker WHERE username = ?"
        },

        # cache settings
        #"memcached" : {
        #       "servers" : [
        #               { "host" : "127.0.0.1", "port" : 11211 }
        #       ]
        #},

        "pid" : "/tmp/pushpoold.pid",

        # overrides local hostname detection
        #"forcehost" : "localhost.localdomain",

        "log.requests" : "/tmp/request.log",
        "log.shares" : "/tmp/shares.log",

        # the server assumes longpolling (w/ SIGUSR1 called for each blk)
        "longpoll.disable" : false,

        # length of time to cache username/password credentials, in seconds
        "auth.cred_cache.expire" : 75,

        # RPC settings
        "rpc.url" : "http://127.0.0.1:9332/",
        "rpc.user" : "user",
        "rpc.pass" : "pass",

        # rewrite returned 'target' to difficulty-1?
        "rpc.target.rewrite" : true,

        # allow clients to update the ntime field of their work
        "roll.ntime.disable" : false
}


texts: How to use two-factor authentication at btc-e?

texts:
btc-e has a very confusing process of enabling 2-factor.
How should I use it?

Should I generate a one time password with a Yubikey?
Should I backup the private key / base32 ?

What does this auth process do?

(P.S. btc-e - you need to hire some better UX people)


texts: Do Coinbase, Coinbase Pro, Robinhood, Gemini, GBTC count as Web Wallet?

texts:
According to a 99Bitcoins video and some writing, Web Wallets are to be avoided because they are not secure.
Does that mean when you buy bitcoins on Robinhood, Coinbase, Coinbase Pro, Gemini, or even the trust GBTC, they are all Web Wallets?
I think Robinhood doesn't even allow us to move the private keys to our wallet, while Coinbase, Coinbase Pro, and Gemini do.
GBTC, I am not sure: if they store the bitcoins "cold" in their trust, then maybe it is not as insecure? Robinhood also said they store a good portion of their bitcoins "cold", and I suppose they only move a small portion to their platform to satisfy the trading or the exchange-for-cash?
So should we consider Robinhood, Coinbase, Coinbase Pro, Gemini, or GBTC Web Wallets and avoid using them for too long but should transfer the private keys into our own wallets?


texts:
Consider the following scenario:

create an entire bitcoin raw transaction while offline (no access to the blockchain)
only when you decided to broadcast it that you would need to get online

Is it possible to do such offline transaction? Exactly what fields you need from the blockchain in order to build such raw transaction?


texts: address that has never been online, will transactions in blockchain still balance?

texts:
I understand that addresses do not have to connect to the bitcoin network/blockchain in order to be valid addresses, but I am mainly wondering about what can be seen in the blockchain if that address has never connected to the network.

So given this scenario

AddressA sends 1 bitcoin to cold AddressB.  AddressB has never been online.

There will be a transaction id for this. But what would a site like blockchain.info show for the balance of AddressB?

Would it still be able to aggregate all of the transaction that go to AddressB to show a balance for AddressB?


texts:
I'd like to better understand how a light client works. As far as I know, a light client stores locally only the block headers (80 bytes each) and it receives a new block header on average each 10 minutes.

I've essentially two questions:

1) How can a light client retrieve a transaction given its hash? I'd like to get back the complete transaction so to read out the data after the OP_RETURN code.

2) How can the light client be sure that the retrieved transaction is really the one in the longest blockchain? Does it simply check if there are 5 blocks already confirmed after the transaction's block?

Thank you very much


texts: Why Satoshi Nakamoto does not want to show up?

texts: The Bitcoin was originally created by Satoshi Nakamoto, and is now becoming a very popular thing. However, I am wondering why the creator of the Bitcoin chose to use a pseudo name as Satoshi Nakamoto, instead of using the real name to make himself or herself famous?


texts: How do you export or save your wallet information for litecoin-qt on ubuntu linux?

texts: I just installed and finally synced up litecoin-qt on ubuntu linux. But how do i backup this wallet and password protect it?


texts: Does the public key associated with an address become part of the public record after it has been used to spend?

texts:
Since bitcoin addresses are hashes of public keys and not public keys as such, if one wanted to craft a message that could be decrypted by the generator of an address, that can't be done just with an address. But after the generator of an address has spent something that was received there, which requires presenting the public key (or does it?) publicly, is that public key part of the public record so it can be used for direct message encryption?

And is there a standard way to perform such message encryption, analogous to opaque PGP blocks, and supported by UI panels in bitcoin-qt where one can paste blocks of plain (with intended recipient) or ciphertext (directed to one of one's own addresses) and see plaintext or a copyable opaque block?


texts: Is there a way to specify an invoice ID in Ripple URI?

texts: In Ripple payment transactions we can specify an invoice ID that is used to make payments for a particular invoice. Is there a way to specify such an invoice ID in Ripple's URI scheme?


texts: Why is a short blocktime considered to be unsafe?

texts: I've heard a couple of times "a shorter blocktime is unsafe," (first about Litecoin and now Ethereum) but never understood why. Is it the higher probability of a fork? Why do some people consider a shorter blocktime less safe?


texts:
Can one, theoretically, write a program that is similar to a solo miner but instead it just logs IPs of other computers on the bitcoin net to trace IPs that might have bitcoin wallets on them and then to use that list as a preferable hacking list ?

I think we can differ between 3 types nodes:
1. people running just the bitcoin client as a wallet
2. people solo mining
3. people pool mining

I am almost sure that the 3rd option is not traceable (assuming the pool servers are secure).
What about the detectability of the first 2 (especially the solo mining).


texts: I was getting 7 mhash/s on GUIminer.. but only 0.3 on bit minter?

texts:
I'm really new to bitcoins. I have a good computer, cpu based at least. 8 core AMD processor with 4 ghz a core with decent amount of cache. I wanted to make some extra money and use my computer to get some bitcoins. Knowing nothing about the industry first thing I did was download wallet and GUIminer. Guiminer keeps taking all the cpu and generates up to 7 Mhash/s However it proves really ineffective, taking all that cpu and showing absolutely no progress on the BTC guild website. So I looked for an alternative method of bitcoin minig that will result in higher reward. I came to bitminter, downloaded their client. When I ran their client, it generated a 0.3 Mhps. This was really disappointing and I don't know why.
Well why is my mhps so low on bitminter, and where should I mine bitcoins?

Also it says "warning: electricity-wasting slow cpu" but I have a beast CPU


texts:
How do Bitcoin vanity generator work and why is there a limit to nine "specific" chars?
I tried looking up the usage, but couldn't find good articles explaining the methodology behind it.


texts: c-lightning channel announcement/establishment issue

texts:
I've been running a c-lightning node over Tor with 2 open channel for a few months and it still hasn't forwarded any payment. Maybe it's normal due to the low amount of liquidity provided by my node, but I noticed my channels status shows this log:

CHANNELD_NORMAL:Funding transaction locked. They need our announcement signatures.

To me it appears like my channels haven't been publicly announced yet.
This is my config file:

network=bitcoin
alias=******
rgb=******
bitcoin-rpcuser=bitcoin
bitcoin-rpcpassword=******
bitcoin-rpcconnect=127.0.0.1
bitcoin-rpcport=8332
announce-addr=******.onion
bind-addr=127.0.0.1:9735
proxy=127.0.0.1:9050
daemon
log-level=debug
log-file=/home/bitcoin/.lightning/debug.log

Am I missing anything?


texts:
I have been holding a small amount of bitcoins on Coinbase and am deciding to move it to wallet.

I wanted to be prepared for the Bitcoin Gold fork coming up in October and was curious about the best approach to go about this so I can eventually get my equivalent Bitcoin Gold (instead of donating it to the exchange)!

If I move my BTC off the exchange/Coinbase and into a wallet, I now officially own it since I have the private key.

If I wanted to take advantage of receiving Bitcoin Gold, I would want to make this move before Oct 25 (obviously smart to move it to a wallet anyway, but I digress..)

After that, I'm a little confused what to do to actually get BTG. I understand someone needs to support it, but what is everyone else doing?

Thanks, hope someone can clarify how to proceed!


texts: Is there any software available for testing of Bitcoin security?

texts: I'm currently in the process of working on my thesis about Bitcoin security and I'm wondering if there's any software available for testing of Bitcoin security? For example, are there any programs that will try launching double-spend attacks, simulate a 51% attack, or the like?


texts: How much Bitcoin was lost in the Jul. 2011 MyBitcoin site shutdown incident?

texts:
https://en.bitcoin.it/wiki/MyBitcoin

How much money was lost when it shut down? (You can also edit the wiki page and add this info). Best estimates of course.


texts: Does Multi_Signature transactions enable trust-less payments? (Edited)

texts:
This paper: (Link to paper) introduces a blockchain based platform entitled PriWatt claiming (in Section 2.5 MultiSignatures, page 3):

  "PriWatt provides the means to form agreements or contracts without
  trusting other party via blockchain."

It continues:

  "This is achieved through multi-signature transaction where minimum m
  of n keys must sign a transaction before tokens can be spend."

(Similar to what we have in Bitcoin n-of-m transactions.)

However, my question is how to remove totally the trust when one party is payer and another party is payee?

I mean multi-signature transactions can be helpful when all of parties are payer. Assume for example a wallet in which a pay out transaction needs minimum m of n signatures. In this case that works.

But, if we consider the example of the paper (same section 2.5) as follows:

  "For example, assume that a customer Alice wants to buy a product
  from a merchant Bob. They make a contract where Bob will not get paid
  until Alice gets a product. Similarly, Alice cannot get a product and
  keep her payment."

However, in this scenario, merchant (Bob) signs 2-of-2 transaction, where it has not been signed yet by customer (Alice). At this point:

(1): If customer (Alice) before receiving the product, signs 2-of-2 transaction, then transaction is payable for merchant (Bob), but what happens if merchant (Bob) does not send the product to customer (Alice)?

Or

(2): What happens if customer (Alice) denies to sign 2-of-2 transaction before receiving the product, and after receiving the product also does not sign the transaction?

Does Multi_Signature transactions can fix this problem? Or merchant and customer need to trust each other?

Edit: In my opinion, a Multi_Signature transaction can remove the trust, IF AND ONLY IF : all exchanged values between parties are internal (for example coin or any other parameter or token etc defined in the code as a variable.) Otherwise if one of values that is exchanged between parties would be an external asset (for example: a product or service like energy in the paper) then parties need to either trust each other or use a trusted arbitrator (trusted Chuck).


texts: How do bitcoin adresses get into the Bitcoin system when they're created offline?

texts:
I am new to Bitcoin, and I am still trying to understand the working of bitaddress.org but get stuck a long the way.

On bitadress.org I can take the site offline and create a public and private key by moving my mouse.

Once my keys are generated I can send bitcoins to the public key.
But as the site is offline how do my keys get into the bitcoin system?


texts: I somehow sent a transaction to my own wallet address

texts:
I wanted to make a transaction to a vendor but somehow I made it to my own address?
It is yellow color and I put very very low fee.
It is unconfirmed yet because of the fees.
Should I just increase the fee by a lot to get my coins back, worth 60£?
And will the coins add automatically in my wallet if both are on the same address?
I only need that ''Yes'' because I'm a rookie and dunno how this will happen.
Thank you.


texts: What is block weight and how is it different from block size?

texts:
While reading about BIP141, I have encountered the following options:

Block creation options:
-blockmaxweight=<n> Set maximum BIP141 block weight (default: 3000000)
-blockmaxsize=<n>   Set maximum block size in bytes (default: 750000)

What is a block weight? Is it a integer representation of the size?


texts: What will happen to my bitcoin if my Ledger or any bitcoin hardware wallet will damaged?

texts: I want to buy a hardware wallet for storing bitcoin because it is safe than an online wallet but at the same time, I am thinking that what will happen to my stored bitcoin if my hardware wallet damaged. Can I recover my bitcoin?


texts:
Given a raw, standard Tx (wiki):

01000000

01
26c07ece0bce7cda0ccd14d99e205f118cde27e83dd75da7b141fe487b5528fb
00000000
8b
48304502202b7e37831273d74c8b5b1956c23e79acd660635a8d1063d413c50b218eb6bc8a022100a10a3a7b5aaa0f07827207daf81f718f51eeac96695cf1ef9f2020f21a0de02f01410452684bce6797a0a50d028e9632be0c2a7e5031b710972c2a3285520fb29fcd4ecfb5fc2bf86a1e7578e4f8a305eeb341d1c6fc0173e5837e2d3c7b178aade078
ffffffff

02

b06c191e01000000
19
76a9143564a74f9ddb4372301c49154605573d7d1a88fe88ac

00e1f50500000000
19
76a914010966776006953d5567439e5e39f86a0d273bee88ac
00000000

and a private key:

18E14A7B6A307F426A94F8114701E7C8E774E7F9A47E2C2035DB29A206321725

How does one construct a new transaction to redeem the coin from the second output? I've been trying to figure this out for a long while using etotheipi's diagram, but can't seem to grasp how a proper transaction is to be created. A step-by-step guide would be welcome.


texts:
In the Schnorr identity protocol, we can transform the interactive ZKP into a non-interactive one by replacing the role of the verifier (i.e. providing a random challenge value) with a hash function that uses the prover's encrypted nonce as input.

s = r + e*x

where:
e = H(r*G)

Validation works by ensuring:

sG== R + e*P

where:
R = r*G

Assume that in this non-interactive model, the prover picks an r value in advance, and runs R through the hash function to determine its  corresponding e digest. Assume the prover is malicious, and is looking to trick a verifier into accepting a Schnorr signature without knowing the private key x. If the prover resuses this e value when constructing the signature, while also selecting an arbitrary s value,they could back out sG = rG-eP. Since the prover knows R, e and P, it seems as if they could convince a verifier that the signature is valid, without needing knowledge of the private key. What prevents this from happening?


texts: Is it possible to have a failed Bitcoin transaction on the block chain?

texts: In Ethereum, a transaction may get out of gas but still being included in a block with a receipt status of failed. In Bitcion, will similar things happen?


texts: Where can I sell domain names and earn in bitcoins?

texts: I want to sell my domain names and receive payments in bitcoins. Some platforms that I know of allow to buy domain names with bitcoins but won't let you sell and earn in BTC. Any platform that allows the same?If that's not possible, any reputed bitcoin-domain escrow that may be of help?Thanks.


texts:
How can i create a wallet for web based application for bitcoin i.e., unique address for each user along with the private key?

Does using bitcoind help me with this and how can i do this ?

I want to create wallet for each user who access a site. How can i do this?

Bitcoind getnewaddress '' command works and produces a new address but where is the private key for this address.


texts: What data is available to Ethereum smart contracts?

texts: I'm wondering - what data is available to the Ethereum smart contracts? I stumbled upon some tutorials on how to write the contracts that give some indication as to a few examples of the data is available, but a more comprehensive list / wiki page would be useful to have for reference.


texts: What sort of service is Bitcoinica (or was before it was closed)?


texts: After sending/flooding transactions, how do we know that a specific transaction is on all nodes?

texts:
In the book "Mastering the Blockchain" by Imran Bashir, it says that a transaction's life cycle is the following:

  A user/sender sends a transaction using wallet software or some other interface.
  The wallet software signs the transaction using the sender's private key.
  The transaction is broadcasted to the Bitcoin network using a flooding algorithm.
  Mining nodes include this transaction in the next block to be mined.
  Mining starts once a miner who solves the Proof of Work problem broadcasts the newly mined
  block to the network. Proof of Work is explained in detail later in this chapter.
  The nodes verify the block and propagate the block further, and confirmation starts to generate.
  Finally, the confirmations start to appear in the receiver's wallet and after approximately six
  confirmations, the transaction is considered finalized and confirmed. However, six is just a
  recommended number; the transaction can be considered final even after the first confirmation.
  The key idea behind waiting for six confirmations is that the probability of double spending is
  virtually eliminated after six confirmations.

My question:

Now all nodes have competing miners to create a block by receiving all transactions by all nodes/users that submit transactions and packing it, which is not coming from one place. If we call the winner, the miner that solves the PoW problem first, then how do we know that he received all the transactions he's supposed to receive before announcing that he created a valid block? My miner software could ignore a few transactions and get to mining earlier than others, and hence beat everyone else (assuming we all have the same computational power).

My question also can be read in a different way: How do ensure that all miners are solving the same PoW problem, while big latency times can be involved in the Bitcoin network (because we're mining from around the world)?


texts: How to know a given file is a valid bitcoin wallet?

texts:
If I have many files on my hard drive (possibly with different names/extension), how can I test which file is a valid bitcoin wallet.dat ?

Maybe there is some string that exists in every bitcoin wallet ?

I guess I am asking about the format of the data inside the wallet.
If wallets are different depending on the bitcoin client, then I want to know about bitcoin core.

Edit: I forgot to mention but these files WERE on a Linux OS. So there should be some solutions.


texts: What properties does the DNSSeed list at bitseed.xf2.org attempt to have?

texts:
According to bitcoinstats.com:

  Except for bitseed.xf2.org the seeds aim to return nodes that are currently online and reachable.

If the nodes are not aimed to be currently online and reachable, what qualities (if any) are they aimed to have?


texts: What's "asm" in transaction input's ScriptSig


texts: Is there a wallet for different cryptocurrencies

texts:
For a person who has different amount of different cryptocurrencies it is actually annoying to use many clients. Right now just Bitcoin data is more than 15 GB, litecoin 1.5 GB and so on.

Is there any wallet which incorporates many wallets? Is it possible?


texts: Bitcoin mining specification to write own mining application

texts:
Where can I find the design specifications to write my own mining application for mining bitcoin.
More I read I find there are number of implementations and some pools only work with specific mining software and there is no way to find single (kind of) wiki that explains the development design specifications.

Till now I find 2 protocols GetWork (which is obsolete now) and Stratum. But within stratum I find input and output implementation varies with different mining applications.


texts: Bitcoin's disappeared from unused wallet

texts:
wondering if I could get some help from you experts on something that has been bugging me for a bit.

I found an old bitcoin wallet I had forgotten about. You can see its information here. I was excited as it seemed to have about $100 in it, so "free money" from the times when I used to mine.

If you look at all the transaction on said wallet, you'll see that they go from 2013-04-14 to 2013-05-08. That's the time when I realised mining bitcoins was slightly fruitless and if I wanted to make some money with it I should probably do something else.

But then you will see there's a transaction on 2014-03-24, which is almost a year later which I don't remember of. That transaction is also transferring out the money from my wallet to another wallet which I don't recollect owning. Seems like my little coins were stolen at this point, and I don't really know how, since they've always been on a local wallet.

Now, I know there's ways people can steal things from local wallets etc, but I was wondering if there's anyway I can try to trace how the coins were stolen. And why is it that the whole amount in said wallet weren't stolen (there's still 0.00038478 BTC in it)

Any light here would be mostly appreciated.


texts: I moved money from my wallet to someone elses wallet over a year ago and they said they never recieved it. Im now desperate to track the money down. Ive found it. But its sitting in a wallet and I dont know how to access the wallet. Please help!!!


texts: NXT - What is the difference between an Asset and a Currency?

texts: Reading the NXT website, it talks about an Asset Exchange and a Monetary System. First seems to be regarding assets, while the second article one is talking about currencies. Is there any difference between those two, is one a subset of the other, or are they all the same?


texts:
On Thursday, August 1st, I withdrew (or so I was given to understand) some dollars from my MtGox account.  They were to be wire-transferred to a checking account in the USA.  When the money hadn't shown up after two weeks, I sent an email to MtGox asking how I could tell where the transaction is in the queue.  I got a reply that didn't answer that question, but said that transactions are taking longer than they would like.  The money still hasn't been transferred.

Is this amount of time typical, or did this somehow get lost?  Is there some way to tell where in the queue I am?


texts: Can't understand arbitrage profit calculation

texts:
Found the formula in the following link. I can't understand with my knowledge. Can anybody explain me with an example?

profit = ExchangeA_sell * (1 - ExchangeA_fee) - ExchangeB_buy * (1 + ExchangeB_fee).

One more thing, Is this formula good for all exchanges? Cryptsy and Bter have calculated differently their net total. Bter sell offer is different from cryptsy sell offer. In Bter the trade fee is deducted just opposite to cryptsy in terms of buy and sell currency?


texts: What exactly are the rev00000.dat files?

texts:
I've been looking at the on disk structured generated by the standard bitcoin-qt client. It looks to me that the rev?????.dat files are reverse application for blocks? So I imagine every single spent output is added to the reverse dat, so that they can be applied directly to the unspent pool during a rewind?

What exactly is stored, and what is the format?


texts: Bitcoin.conf doesn't exist in my Windows 10

texts: I am in dire need to prune the blockchain because of the storage space on my computer being completely clogged up now. But I cannot locate the files. I have found the directory, but the bitcoin.conf file simply doesn't exist. Please help me!


texts: Block Validation Process, in Terms of adding Block to the Chain

texts:
quick question - How does a Node react to a new block propagated to the network?
In Terms to  does a Miner stop mining when "he" gets information of a new block to validate it? or does it not stop and validate it in another Thread?
If the Question is unclear - let me know I just began my deep dive into the technical side of Crypto and Blockchain :)
best regards :)


texts: Can Bitcoin(PoW) work under partial synchrony?

texts:
This paper rigorously proves that Bitcoin can achieve consensus under the assumption of bounded message delivery time:

  Messages  in  a  mailbox may  be  delivered  in  any  order,  and  at
  any  time,  except there is a maximum delay of ∆

If I understand it correctly, this only proves it works in synchronous network. If so, this assumption seems relaxed to me.

Tendermint paper claims it can work under the partial synchronous assumption (from DLS paper):

  There is assumed to be some unknown upper bound ∆ on the time of
  messages to be delivered.

The setup is more general in that the upper bound ∆ here is unknown.

Can Bitcoin protocol achieve consensus in partial synchronous network as well? Is there any theory work dedicated to proving that?


texts: Blockchain.info http://blockchain.info/connected-nodes shows a list of nodes it is connected to. Is it possible for me to add them as a node for connection?


texts: Bitcoin full node installation on Raspberry Pi3 not working

texts:
I'm trying to setup a Bitcoin full node including GUI & wallet based on guide on raspnode.com but I got stuck at the this point:

'i@raspnode~/bin/bitcoin$ make -j2'

having this error:

Making all in src
make[1]: Entering directory '/home/pi/bin/bitcoin/src'
make[2]: Entering directory '/home/pi/bin/bitcoin/src'
  CXX      bitcoind-bitcoind.o
make[3]: Entering directory '/home/pi/bin/bitcoin/src/secp256k1'
make[3]: Leaving directory '/home/pi/bin/bitcoin/src/secp256k1'
  CXX      libbitcoin_server_a-chain.o
  CXX      libbitcoin_server_a-checkpoints.o
In file included from /usr/include/boost/thread.hpp:24:0,
             from scheduler.h:15,
             from bitcoind.cpp:15:
/usr/include/boost/thread/future.hpp:3188:0: error: unterminated #if
 #if ! defined BOOST_NO_CXX11_RVALUE_REFERENCES
 ^
/usr/include/boost/thread/future.hpp:3164:0: error: unterminated #if
 #if defined BOOST_THREAD_PROVIDES_FUTURE_CTOR_ALLOCATORS
 ^
In file included from /usr/include/boost/thread.hpp:24:0,
             from scheduler.h:15,
             from bitcoind.cpp:15:
/usr/include/boost/thread/future.hpp:16:0: error: unterminated #ifndef
 #ifndef BOOST_NO_EXCEPTIONS
 ^
/usr/include/boost/thread/future.hpp:8:0: error: unterminated #ifndef
 #ifndef BOOST_THREAD_FUTURE_HPP
 ^
In file included from util.h:18:0,
             from bitcoind.cpp:16:
tinyformat.h:104:1: error: expected unqualified-id before ‘namespace’
 namespace tinyformat {}
 ^
tinyformat.h:109:1: error: expected unqualified-id before ‘namespace’
 namespace tfm = tinyformat;
 ^
In file included from util.h:18:0,
             from bitcoind.cpp:16:
tinyformat.h:150:1: error: expected unqualified-id before ‘namespace’
 namespace tinyformat {
 ^
bitcoind.cpp:191:1: error: expected ‘}’ at end of input
 }
 ^
In file included from bitcoind.cpp:15:0:
scheduler.h:80:87: error: expected unqualified-id at end of input
     bool shouldStop() { return stopRequested || (stopWhenEmpty && taskQueue.empty()); }
                                                                                ^
scheduler.h:80:87: error: expected ‘}’ at end of input
Makefile:7351: recipe for target 'bitcoind-bitcoind.o' failed
make[2]: *** [bitcoind-bitcoind.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: Leaving directory '/home/pi/bin/bitcoin/src'
Makefile:8357: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/home/pi/bin/bitcoin/src'
Makefile:668: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1

PLEASE HELP!


texts:
I am manipulating (with pybitcointools) some regular addresses as well as some P2SH and stumbled upon the following:

Case 1:

>>> b58check_to_hex('17rq8m5SW8XoZ9dHEkQyBfc5w2XQnQvznz')
'4b3d51202139ff109f6d10b637081f2de48d4b35'
>>> hex_to_b58check('4b3d51202139ff109f6d10b637081f2de48d4b35')
'17rq8m5SW8XoZ9dHEkQyBfc5w2XQnQvznz'

second command is the inverse mapping of the first one

Case 2:

>>> b58check_to_hex('3BRu7EhouApLkW1EZ64T9o9yMuX5Rexz6f')
'6ad55439d8faab476bbc0f89183ce689f8f6985b'
>>> hex_to_b58check('6ad55439d8faab476bbc0f89183ce689f8f6985b')
'1AjtBhDNMGVxfLJoRzPrjAo3DPEMps6xEd'

second command is NOT the inverse mapping of the first one

This surprises me a lot. Can someone give me some hints as to why this is the case please?

Thank you


texts: Single API to Get Fee Estimates for All Major Cryptocurrencies?

texts:
Many sites provide estimates of miner/gas fees for individual cryptocurrencies. For example, EtherScan provides gas estimates for ETH. BTC Network provides fee estimates for Bitcoin.
Both of these sites provide API functionality, but they are limited to a single cryptocurrency. If I wanted to integrate many cryptocurrencies into my site I would need to integrate a different API for each of the cryptocurrencies I support.
I'm looking for a site/solution that offers a single interface to obtain gas/transaction/miner fees for all major coins such as BTC, ETH, LTC, BCH, USDT, USDC, XRP etc. The API must also provide estimates based on the desired transaction confirmation times. In other words, I should be able to request estimated fee if I want 90% likelihood of confirmation within the next 30 min, 60 min, 600 min and so on.
Update: Can someone please explain in the comments why this is off topic? 1) this question IS applicable to Bitcoin (questions in which the answer is the same for Bitcoin are on topic) 2) I am not seeking a product or service review I am asking if such a service exists (it's a factual question) How does this question differ from:
Historical BTC data in JSON
API for automatical buying and selling coins in Java
Which asks for a specific service/API..


texts: Why do mining pools refuse "spammy" transactions when there are transaction fees already?

texts:
So I stumbled over a problem with some non relayed transactions. A helpful user was finally able to point out that some services (Satoshi Dice) that accept BTCs are regarded as a nuisance by mining pools, so they flat out reject to relay their transactions.

I can understand the rationale that there is scarcity in resources and all. Surely it takes a toll on the network if lots of small transactions clog up what limited processing power there is - but isn't this exactly why there is such a thing as a transaction fee? Isn't the whole point of such a fee to prevent people spamming the network?

Did I misunderstand how this works or is it really okay in the Bitcoin network to refuse transactions based on personal preference of the operators (aka Miners), in kind of like the censorship style that many proponents of BTC aim to avoid?


texts:
One of my kids while learning more about bitcoin started bitcoind on my mac. Now I am unable to stop it. In my activity monitor, it shows a process named "bitcoind". I have stopped that process from the activity monitor various times but that doesn't help. It starts again after some time or in the next boot session. It has been taking a lot of my laptop space (>100gb). I am running low on space and I need to stop it now. This has been happening regularly. As a temporary solution, I used to go to /Users/[name]/Library/Application Support/ and delete the "Bitcoin" folder from there. But that's no proper solution to end it completely. I have tried a bunch of stuff using bitcoin-cli in the terminal. However, I am unable to stop it.
Running
bitcoin-cli stop returns error: couldn't connect to server: unknown (code -1) (make sure server is running and you are connecting to the correct RPC port).
Can someone please tell me what should I do to stop the bitcoind?


texts:
Firstly, let me show my version:

[frank@localhost bin]$ ./bitcoin-cli -version
Bitcoin Core RPC client version v0.16.1

After sendrawtransaction and I got:

  error code: -26 error message: 64: non-mandatory-script-verify-flag
  (Signature must be zero for failed CHECK(MULTI)SIG operation)

And then, I try to decoderawtrsanaction the hex, and then I got the following output:

[frank@localhost bin]$ ./bitcoin-cli -regtest decoderawtransaction 020000000001018cc2f3c4f1af3ad60f3f3dcf5e3c3bfadb824e22aadec877f5a2bc4f99029dab0100000017160014c21bbdc4a642e391a6401bf30ac3e4e8e9669ea2ffffffff01605af4050000000017a914317fec65edbff6e4350fbe668cfedaf54ea9061587024730440220288b7912b6f6c0734ee34cada2c20fc81e8a7e11b4ccc9285b204eb25da953fa02205040878b44db8b17c8d62822c9124a4b154b46ccbd321fddfd52b9acd6742e1f032102efff391c5baf1433e2c488271ceebaa6eb2a203000ff62320de13d07b1ec4f4c00000000
{
  "txid": "42f6612dedacb4b5a24ffb75c07ae61eb939bb40c039fb165284bbac516b1e78",
  "hash": "6db7c04b006407655f55f2e64057d6ced61d34ee9b96ae9bcf5ead6dc311ecaf",
  "version": 2,
  "size": 215,
  "vsize": 134,
  "locktime": 0,
  "vin": [
    {
      "txid": "ab9d02994fbca2f577c8deaa224e82dbfa3b3c5ecf3d3f0fd63aaff1c4f3c28c",
      "vout": 1,
      "scriptSig": {
        "asm": "0014c21bbdc4a642e391a6401bf30ac3e4e8e9669ea2",
        "hex": "160014c21bbdc4a642e391a6401bf30ac3e4e8e9669ea2"
      },
      "txinwitness": [
        "30440220288b7912b6f6c0734ee34cada2c20fc81e8a7e11b4ccc9285b204eb25da953fa02205040878b44db8b17c8d62822c9124a4b154b46ccbd321fddfd52b9acd6742e1f03",
        "02efff391c5baf1433e2c488271ceebaa6eb2a203000ff62320de13d07b1ec4f4c"
      ],
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 0.99900000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_HASH160 317fec65edbff6e4350fbe668cfedaf54ea90615 OP_EQUAL",
        "hex": "a914317fec65edbff6e4350fbe668cfedaf54ea9061587",
        "reqSigs": 1,
        "type": "scripthash",
        "addresses": [
          "2MwkxLxbgdZKGEN4fS8GQATqQGXyRpFbkuf"
        ]
      }
    }
  ]
}

I don't know what I missed? Any one know?


texts: A block is generated every ten minutes. The reward changes periodically, and will halve 32 more times. What is the approximately daily reward across the entire network?


texts: While reading NXT's API wiki page I came across something called a "lessor", but I can't find its definition anywhere. What is a lessor?


texts: Question regarding stale blocks and the heaviest chain

texts:
According to this website: https://forkmonitor.info/stale/btc/644543, at the block heigh 644543 multiple blocks were produced. If I understand correctly, in Bitcoin, the heaviest chain survives, while the other block(s) become stale.
So, in this case, the "empty" block containing one COINBASE transaction 644543 survived, while the block: https://www.blockchain.com/btc/block/0000000000000000000ac8d61492ab76dab7451373c6eaa6803ec0244f623395 (containing 2,426 transactions) became a stale! Moreover, the stale block was mined 3 seconds earlier.
Questions:

how the chain containing the "empty" block was heavier than the chain containing the stale block?
Is the mined block time important in resolving such situations?


texts: How to pass password with special characters to RPC API via curl?

texts:
When I set a simple password in my .conf file

rpcuser=user
rpcpassword=password

I can contact my wallet using curl from the command line like so:

$ curl --verbose --user 'user:password' --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "getbalance", "params": [] }' -H 'content-type: text/plain;' http://127.0.0.1:18332/
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 18332 (#0)
* Server auth using Basic with user 'user'
> POST / HTTP/1.1
> Host: 127.0.0.1:18332
> Authorization: Basic dXNlcjpwYXNzd29yZA==
> User-Agent: curl/7.50.1
> Accept: */*
> content-type: text/plain;
> Content-Length: 74
>
* upload completely sent off: 74 out of 74 bytes
< HTTP/1.1 200 OK
< Content-Type: application/json
< Date: Τετ, 21 Ιούν 2017 08:59:30 GMT
< Content-Length: 52
<
{"result":14.13139559,"error":null,"id":"curltest"}
* Connection #0 to host 127.0.0.1 left intact

But if I set a more complex password with special characters, such as

rpcuser=user
rpcpassword=!@#$%^&*()

then the call fails with 401 - Unauthorized

$ curl --verbose --user 'user:!@#$%^&*()' --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "getbalance", "params": [] }' -H 'content-type: text/plain;' http://127.0.0.1:18332/
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 18332 (#0)
* Server auth using Basic with user 'user'
> POST / HTTP/1.1
> Host: 127.0.0.1:18332
> Authorization: Basic dXNlcjohQCMkJV4mKigp
> User-Agent: curl/7.50.1
> Accept: */*
> content-type: text/plain;
> Content-Length: 74
>
* upload completely sent off: 74 out of 74 bytes
< HTTP/1.1 401 Unauthorized
* Authentication problem. Ignoring this.
< WWW-Authenticate: Basic realm="jsonrpc"
< Date: Τετ, 21 Ιούν 2017 09:03:05 GMT
< Content-Length: 0
< Content-Type: text/html; charset=ISO-8859-1
<
* Connection #0 to host 127.0.0.1 left intact

It doesn't seem like the password was mangled at the shell level. It was passed verbatim.

$ echo dXNlcjohQCMkJV4mKigp | base64 -d
user:!@#$%^&*()

There must be a way to do this, because bitcoin-cli works with the complex password just fine.

$ bitcoin-cli getbalance
14.13139559

Looking into bitcoin-cli.cpp it seems the client is using basic HTTP auth, which is consistent with what the wiki says.

strRPCUserColonPass = GetArg("-rpcuser", "") + ":" + GetArg("-rpcpassword", "");

...and later on...

evhttp_add_header(output_headers, "Authorization", (std::string("Basic ") + EncodeBase64(strRPCUserColonPass)).c_str());

Can someone please figure this out for me?

I want to know because I'm trying to pass complex passwords into EasyBitcoin-PHP and failing.

Thanks.


texts: Open source, how can I view "Transaction Create a new transaction" and "Sign Transaction"?

texts:
Not long ago I saw on the site github.com the very first Nakamoto code:

https://github.com/livegnik/BitCoin-v0.01-ALPHA

Running bitcoin.exe, I did not find the console. If the program is open source, how can I view "Transaction Create a new transaction" and "Sign Transaction"?

I know that the program is written in C++
I would love to see the "Transaction" processes as on https://coinb.in
Coinbin source code is written in javascript. Can I view in C++?


texts: How to accept Bitcoin payments using Bitpay and Electrum for a business

texts:
Our company uses a standard invoicing model where we bill our clients the service charge and require payment within X days. We'd like to be able to add a "Pay with Bitcoin" option on the invoices. We are thinking we'd use a service like Bitpay to facilitate the payment and then have Bitpay send the BTC to our business wallet which uses Electrum.
What are some important considerations? Although Electrum generates several wallet addresses, Bitpay only allows entering a single address. Is this okay? I've seen recommendations to always use different addresses, but I can't figure out how to do this with Bitpay.
Perhaps another service instead of Bitpay would be a better option...


texts: How can one find everyone holding IOUs from a given issuer in Ripple?

texts: In Ripple, anyone can issue IOUs, which later can be passed on to other parties in the network through a web of trust. How can one find every account holding IOUs from a given issuer? Would it need to be done through crawling the trust network, or is there an easier way?


texts: Can you send partial amounts of zcash to a zaddress or do you have to send all of it to a zaddress?

texts: Reading the tutorial online, they say to use: z_sendmany to send to a z address. But can one send partial amounts to a zaddress from a taddress? Also what if one wanted to send partial amounts from a zaddress to a taddress/zaddress? Is this doable without using z_sendmany option?


texts: Attack the network by temporarily adding hash power?

texts:
Could a malicious actor (e.g. government) attack the network by introducing significant compute power into the network, and once the difficulty grows very high, withdraw all resources from the network.

This could dramatically increase the time it takes for transactions to be confirmed, as well as makes it not profitable for other miners. Granted this would only last until the difficulty is readjusted, but perhaps it could be enough to shake public confidence in the network.


texts: Why are Virtual Machines used in Ethereum?

texts:
I'm wondering why the Ethereum Virtual Machine (EVM) is used?

What if they didn't use it?

Why don't we have them in Bitcoin?


texts: Calculating P2WKH nested in P2SH addr/redeem script hash from pubkey

texts:
My calculation of the hash160 doesn't seem to be correct - what are my sins?

Tx spending the input: https://www.blockchain.com/btc/tx/d490cc0a5b9799e09b02dd4b20a6d7ca297c09c425983efc13b382f6023d0376

Spent output's scriptPubKey: OP_HASH160 032d2c15611c7b4b6941e62011e58cb5e204baa5 OP_EQUAL

Spending signature:

'txinwitness': ['3045022100b36d2efceb87bd89466d10ee31e5c76c775d9df71095a39c38bd8c5d64fc78d202201dddf5579d993d013eb73b58110e3d280364ec47b1d7617c2f6d842e7d243d6f01',
'02d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422']

So the pubkey is '02d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422'

My understanding is that the redeem script should be:

2102d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422ac (classic P2SH with OP_CHECKSIG)
or

0002d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422 for P2WPKH-nested-in-P2SH.  [this is wrong, see below]

The expected hash output of the redeem script is:
032d2c15611c7b4b6941e62011e58cb5e204baa5 (see scriptPubKey above)
My hash outputs:

ripe160(sha256('2102d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422ac')) = 9e75bbd28314946ea5bcea5e217982fce698b041

ripe160('0002d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422') = 1c868bec66729c87e4cb60ec6d1c8846ad86d0ee

Saw this answer (P2sh redeem script hash), my calculations work fine with those inputs, but not with the above.
Related question: what is the role of the sigScript
0014cc38458a6e5c8c09e1d8fac905fb1024c8678d88 in the input if we have the txinwitness?
EDIT: mystery solved
Since scriptSig was not empty, it means that the transaction was a nested P2SH transaction. In this case it is a P2WPKH nested in BIP16 P2SH.
So in order to get the expected redeem script hash 032d2c15611c7b4b6941e62011e58cb5e204baa5 (which is base58 transformed, with a 0x05 byte appended at the beginning, to obtain the bitcoin address 31yp4jocJSRG4Wa8aV7ocKSXKcdWzkHy61):
using the scriptSig asm = 0014cc38458a6e5c8c09e1d8fac905fb1024c8678d88
so
ripe160(sha256('0014cc38458a6e5c8c09e1d8fac905fb1024c8678d88')) = 032d2c15611c7b4b6941e62011e58cb5e204baa5 = desired result (which can be base58 transformed into the bitcoin address).
The scriptSig asm is in this case a P2WKH redeem script, which is obtained as from the pubkey:
0x00 + ripe160(sha256('02d0a9b9f420d22e3c1de27e87c6ff2ec33da21302cf07688b53d72c07e88d0422')) = 00 cc38458a6e5c8c09e1d8fac905fb1024c8678d88


texts:
has electron cache 2 history pages: bitcoins and bcc?
in a youtube video I see only one history page with a sending and receiving tab: what is this:bitcoins or bcc?
I want to start a wallet with 0 bitcoins and 1 bcc via a seed of an old blockchain.info wallet.


texts:
I'm running out of ideas and I'm hoping to get some help.
My computer crashed but I have the wallet.dat file on a thumb drive. I've downloaded and synced v0.18.1 on a new computer but don't see any way to add the .dat file using the GUI. Do I have to use the command line prompts? If so, the proper procedure would be very helpful.
I did see a similar situation on this forum but the advice given was over my head.
Thanks to anyone who can help.


texts:
I just started mining today at Dogechain pool. I wanted to see what mining was like, so I'm only using minerd with my CPU. I don't expect a lot until I get a GPU rig going, but something doesn't seem right.

For instance, I'm averaging 8-10 kH/s hashing rate (sometimes as high as 15, sometimes as low as 5). On minerd, after about 6 hours I'm over 200/200 accepted, but on Dogechain pool, I've only earned 21 Dogecoin. During the last block round, my shares went over a 100, and in the pool stats, it shows my hashrate as averaging between 225 and 250 doge/day. At this rate, I'll only be earning about 80 a day. According to coinwarz at 8 kH/s, I should at least be earning 108 a day.

It seems like the rate of reward is really low, even for CPU mining. Can anyone give me an idea why?


texts: How is block-solution-withholding a threat to mining pools?

texts:
If I understand the technical process (for most mining pools) correctly, a participant in a mining pool is given block data to combine with a nonce to try to solve the block. If they get close (but not close enough to give the actual solution) to solving a block, they have solved a "share", and at that point return proof-of-work to the mining pool to receive a share of the final payout when the block is solved.

However, the participant performing the mining DOES know if they actually solve the block. At this point, a malicious miner running custom mining software could potentially choose to not send the solution to the pool. I think I have seen this referred to as a "solution withholding attack".

How vulnerable are pools and pool-miners to this threat?

[Edit]: Also, what can pools do to detect or deter this threat?


texts: Low hashrate with cgminer 3.7.2 kalroth edition @ ubuntu 13.10 x64 @ R9 290 MSI GAMING EDITION @ 16 gb ram @ core i7 860

texts:
I'm trying with (below my sh file):

export DISPLAY=:0
export GPU_MAX_ALLOC_PERCENT=100
export GPU_USE_SYNC_OBJECTS=1
cd /home/x/cgminer-3.7.2-kalroth/
find *.bin -delete
sleep 3

cgminer --scrypt -o stratum+tcp://stratum.fast-pool.com:3333 -u user.x -p pass --thread-concurrency 24550 --lookup-gap 2 --auto-gpu --gpu-engine 950 --gpu-memclock 1250 -w 512 -I 20 --gpu-powertune 20 --auto-fan --gpu-fan 40-100 --temp-overheat 90 --temp-target 85 --temp-cutoff 95 -g 1

This gives me average ~660 kh :(

I was trying also with config from GUI miner for windows called "R9 290 high":

cgminer --scrypt -o stratum+tcp://stratum.fast-pool.com:3333 -u user.x -p pass --thread-concurrency 32765 --lookup-gap 2 --auto-gpu --gpu-engine 950 --gpu-memclock 1250 -w 256 -I 20 --gpu-powertune 20 --auto-fan --gpu-fan 40-100 --temp-overheat 80 --temp-target 75 --temp-cutoff 85 -g 1

but it gives e something like this:

 [2014-02-13 11:00:29] Started cgminer 3.7.2
 [2014-02-13 11:00:29] Started cgminer 3.7.2
 [2014-02-13 11:00:29] Probing for an alive pool
 [2014-02-13 11:00:29] Pool 0 difficulty changed to 128
 [2014-02-13 11:00:34] Maximum buffer memory device 0 supports says 774897664
 [2014-02-13 11:00:34] Your scrypt settings come to 2147287040
 [2014-02-13 11:00:34] Error -61: clCreateBuffer (padbuffer8), decrease TC or increase LG
 [2014-02-13 11:00:34] Failed to init GPU thread 0, disabling device 0
 [2014-02-13 11:00:34] Restarting the GPU from the menu will not fix this.
 [2014-02-13 11:00:34] Try restarting cgminer.

Above configs works fine (better hashrate) on windows 7 64, but i prefer to use ubuntu beacause windows is unstable.

Anyone can help me?

I have installed latest catalyst, sdk ofcourse.


texts: I purchased one in 2009 or 2010 . I want to know how I would recover it. I was sent to prison I would like to know asap please and thank you .


texts: Configuring Windows Bitcoin Core Wallet for use on Tor

texts:
I use Bitcoin Core v0.12.1 (64bit) for Windows as my desktop wallet for transactions on the regular web. I am just getting set up to use Tor. I would like to configure Bitcoin Core for use on Tor as well. When I opened Settings|Options|Network tabs I found a pre-checked marked box labeled "Allow incoming Connections" In addition to that I have checked marked the box labeled "Use Separate SOCKS5 proxy to reach peers via Tor hidden services" ProxyIP: 127.0.0.1  Port:9050.

Is this all that I really need to do? I've been reading up on bitcoin.conf and the command line options. It all seems horribly complex. I'm just an average schmo not some power user. I wouldn't know which options to pick or what values to assign. I would appreciate any thoughts and suggestions on the subject.