texts: Does the pool miners in mining pool receive the same block in case of a fork?

texts:
For example there are 2 mining pools A and B and they mined a block in same time.

Then, A mining pool got a block that A mining pool mined?

Or nodes in mining pool receive independently so they select block regardless of mining pool?

I have known nodes choose a block which are propagated early to them and block is propagated not geographically close node but randomly (I mean block is propagated close nodes but this ‘close’ do not mean geographically close but close in network).

When miner is mining or propagating, miner can recognize which node is mining in same mining pool?


texts: Buying Bitcoins without verification and documents

texts: I need to buy Bitcoins with Visa or MasterCard, but without verification and documents. The amount of purchase is large. Can you suggest such online services?


texts: Doesn't creating a masterkey password on Kraken void the protection of 2FA?

texts: Kraken allows users to create a masterkey that is just a password. Wouldn't creating a password to bypass 2FA completely negate 2FA?


texts: Hardware Bitcoins (Smartcards, RFID etc.)

texts: is it possible to create a real hardware Bitcoin, e.g. a specified (and verifiable) value which is stored on a smart card or RFID which can be given directly to other people?


texts: Classifying Miners based on their Location

texts:
Is there any way to classify the bitcoin miners based on their geographical locations?
Is there any possibility of doing so for the participants in cooperative mining as well?
Thank you


texts: Can we think of an address a mini-account, and is re-useable and disposable?

texts: Can we think of an address as a mini-account, and we can keep on using one, or we can use many to add privacy to our activities, and we can transfer or sell the bitcoins in it and make them empty and dispose of them any time?


texts: I have not received my bitcoin after 2 days and 115 confirmations

texts:
I have sent my first Transaction and waiting for it to arrive at another address but when i click on the Transaction ID 1 of the addresses is Spent and the other is Unspent? It only required 3 Confirmations but is now 115? Where is my bitcoin and how do i receive it?

Thanks in Advance


texts: How can you create an off chain transaction and broadcast it?  Is it the same as creating a non standard transaction or different?


texts: What are the downsides of integrating accumulators like utreexo to bitcoind?

texts:
Inspired by the discussion in this question I wonder what would be the downsides of adding accumulators like utreexo (paper at: https://eprint.iacr.org/2019/611.pdf) to bitcoind?

On the positive side it seems like a huge improvement if we don't need to store the history of all transactions but rather rely on merkle proofs.


texts: Bitcoin core: boostrap.dat trade-off with "Synchronizing with network..."

texts:
Being, now, aware that users of Bitcoin Core (v0.12.1.0-g9779e1e) are no longer to use a torrent download of a bootstrap.dat and, instead, are admonished to simply launch Bitcoin Core and permit "Synchronizing with network...", I nevertheless have a situation that may require a more nuanced decision:

I'm recovering from a backup and it says "50 weeks behind..."
By the time I discovered boostrap.dat was no longer faster I had already torrent downloaded most of boostrat.dat.

Number 1 leads me to believe my use case may be an exceptional use case that may download everything for the last year before becoming operational again -- rather than the minimum amount(?) necessary to begin secure operation.

Number 2 means I may be able to complete the download in about 12 hours to SATA SSD and then be able to load from that file only the minimum amount(?) necessary in a total amount of time much faster than downloading "50 weeks behind" of blockchain.

Should I go ahead with the torrent of bootstrap.dat and load it or should I stop the torrent and just let Bitcoin Core complete "Synchronizing with network..." even though it says "50 weeks behind"?


texts: Is it possible that transactions throughput will grow to beyond what can be synchronized?

texts: The number of users increases, and thus the number of transactions. Is it possible that in the future transactions arise faster than I can sync them?


texts: Why does "???" replace some values in this p2pool output?

texts:
2013-07-09 00:46:43.467000 P2Pool: 17468 shares in chain (17472 verified/17472 total) Peers: 9 (3 incoming)
2013-07-09 00:46:43.467000  Local: 0H/s in last 0.0 seconds Local dead on arrival: ??? Expected time to share: ???
2013-07-09 00:46:43.468000  Shares: 0 (0 orphan, 0 dead) Stale rate: ??? Efficiency: ??? Current payout: 0.0000 BTC
2013-07-09 00:46:43.468000  Pool: 1202GH/s Stale rate: 16.9% Expected time to block: 21.2 hours

Why are a bunch of values just "???".


texts: I had to update the software on my computer and had to delete everything on my computer. I wasn't aware that my Bitcoin wallet was like a physical wallet. I thought I'd be able to download the wallet and enter my address into it and get everything back. I don't know what to do. I'm freaking out and don't know how and if I can get my Bitcoin wallet back. I know the address of my wallet but I don't have any of the files on my computer.


texts: Why BIP32 derive address does not match with BIP39?

texts: How is that the same xPub rsults different address in BIP32 and BIP39? :)


texts: What is the Optimal block size based on 90 percentile block propogation delay?

texts:
We can have pruned nodes that can verify blocks and transactions so the block size can be increased without leading to the centralization of block verification.
But if we increase block size then block verification time and propagation delay will increase. It will increase the probability of two miners mining a block simultaneously and also delay the competing blockchain branches to resolve the dispute. Probably any increase in block propagation delay will increase the time to resolve disputes exponentially.
Based on a website (Can't remember) currently, block propagation delay is 5 seconds to reach 90% nodes which may increase to 15-20 seconds if all transactions were Segwit.
I think block propagation delay is the only limiting factor in increasing block size.
Has anyone done an investigation to find out the relationship between block propagation delay and optimal block size?


texts:
I know the Satoshi Nakamoto profile: https://bitcointalk.org/index.php?action=profile;u=3 and his public key: http://forum.bitcoin.org/Satoshi_Nakamoto.asc

And I know maybe Satoshi is not a real person, but a pseudonymous of a group of people.

But there is a way to send a message to Satoshi? Is there a public email? Any kind of contact?


texts: Where to find rpcauth.py for configuring rpcauth in bitcoin.conf on Ubuntu

texts:
I can't find the python file to create the rpc credentials. According to the documentation it should reside somewhere here:

  using the output from the script in share/rpcauth/rpcauth.py


texts: What is confirmation notificaion in bitcoin via block chain API

texts:
I have used bitcoin block chain API in my website, it works and i updated the db when call back the function call but the problem is that db updated multiple times

my codes are

if ($_GET['confirmations'] >= 6) {
    //payment confirmed
    //do some DB oparation
}

i want to know in which case the paymnet is confirmed and how could i update DB once.

Thanks


texts: "No more backup pools left. Using primary and starting over."

texts:
I am not using a pool, I am using my graphics cards mining with poclbm over rpc. i do not understand why I get these messages.

localhost:8332 15/08/2012 22:40:13, No more backup pools left. Using primary and starting over.
localhost:8332 15/08/2012 22:40:13, Setting server (MYUSERNAME @ localhost:8332)
localhost:8332 16/08/2012 13:15:35, No more backup pools left. Using primary and starting over.
localhost:8332 16/08/2012 13:15:35, Setting server (MYUSERNAME @ localhost:8332)

Is this something that is fixable? Should I bother (does it affect the mining in any significant way)?


texts: Are the indexes generated by txindex=1 persisted to disk?

texts:
I'm running bitcoind with the option -txindex.

$ bitcoind -txindex

it seems to be taking around a day to fully index the whole blockchain.
(I'm using a raspberry pi 4, 4GB of Ram, with an external Hard Drive).

If I shutdown bitcoind and restart, is it going to reindex all transactions again or just load the indexes from disk?


texts: Get filtered block for a given transaction using bitcoinj

texts:
I am currently working with bitcoinj to interact with bitcoin node.

I am trying to obtain a filtered block for a given transaction or public key. Is it possible?


texts:
I have one computer with windows 8.1 13.11 driver and a 280x which gets 720KHS and another computer with the same setup which gets 620KHS.

They have a different cpu ram and psu (both have quality ones).

How can this be?


texts:
Does solo mining still exists in Bitcoin or other alt-coins?

Is there a source of statistic about the share of pooled mining for the main alt-coins (similar to this for Bitcoin and this for Ethereum)?


texts:
I have my ECKey key. In order to create an ECDSASignature object with BitcoinJ, we have to call ECDSASignature mySignature = key.sign(Sha256Hash input).

Is the Sha256Hash input my message? Or is it the result of Sha256(byte[] myArray)?

What if I don't have a message to sign? Is it acceptable to sign the key.getPrivKeyBytes() in order to create an ECDSASignature, or it is unacceptable because it reveals information including in getPrivKeyBytes() and as a result reveal my private key?

And if it is unacceptable what must be my message? Can I can sign whatever I want in order to create my ECDSASignature?


texts: Can a Qubit Miner ASIC device be created and what would its impact be on the mining community?

texts:
With mining gaining in popularity every day and the raw power of the ASIC devices increasing at a dramatic rate, I wonder what is the next big jump for miners.

Qubits, or quantum bits, have already shown to be extremely fast at calculations.  That makes them seem like a perfect fit for mining bitcoins.

This question is asking if a qubit device can be created for mining bitcoins and, if so, how it would affect the current mining community using standard zeros and ones.  To ask this another way...

How much faster would a qubit device mine bitcoins when compared to an existing ASIC device today?  Let's compare it to ButterflyLab's Mini Rig which runs at 500 GH/s.  Ten, hundreds, thousands, millions times faster?  Could quibit devices destroy the bitcoin network by controlling more than 51% of the network?


texts: Using key aggregation (multsig) in P2TR script path spends

texts:
I know that it is possible to create a 2-2 multsig using Taproot by combining both private keys into one public key and defining that as the key path spend. I also know that it is possible to use Tapscript to do the same thing with a script path spend using OP_CHECKSIGADD.
Is it also possible to use key aggregation in the script path spend, by just providing a public key and signature but doing the same key aggregation as in the key path spend? If so, would it ever make sense to use a "normal" OP_CHECKSIGADD operation in the case of multisig (not threshold signatures).


texts: Unable to access Wallet in Multibit HD - currupt password

texts:
After my computer died and was rebuilt I'm trying to restore access to my bitcoin wallet.

I have my wallet words with I've confirmed are correct as I've used them in the past.

I try to restore my wallet by entering my wallet words, which are accepted, then select my backup which is located correctly.
Then I get the restore report saying
 Backup location created
 Wallet Created
 security certificates
 wallet is synchronising. please wait until complete.

but as the wallet fails to create I don't think it can synchronise. the screen stays like this until I cancel.


texts: Filter transactions per block 50 BTC or Higher

texts:
I'm using the blocktrail python api, to try and display transactions above 50 BTC per block for a visualization project. I think I'm almost there but can anyone help me understand where I'm stuck?

client = blocktrail.APIClient(api_key="MY_APIKEY", api_secret="MY_APISECRET", network="BTC", testnet=false)

def getLargeTxs():
  block = client.block_latest()
  transactions = client.block_transactions(block)['data']
  over_50btc = [ item for item in transactions if blocktrail.to_btc( item['estimated_value'] ) > 50.0 ]
  return over_50btc

Thanks for your help


texts: Is Ripple an anti central exchange that makes Bitpay and Mt.gox almost obsolete?

texts: I just learned of Ripple and it still seems a bit fuzzy to grasp the concept, but from what I gathered so far its a decentralized exchange that basically has the potential to overtake Bitpay and Mt.gox. I read that there are Gateway points that do the currency conversions from bitcoin to fiat. Now the other question I have is how does Ripple derive the bitcoin exchange price if everyone starts abandoning traditional exchanges that kind of dictate the price exchanges from fiat to btc. Obviously not everyone is going to abandon those exchanges anytime soon.


texts: How Does Network Difficulty Relate to the Odds of Finding a Block?

texts:
Right now the network difficulty for mining is 40640955016.576. And, according to blockexplorer.com, the current odds of finding a block for any given hash is 0.0000000000000000000057288784391318092718842084135055792.

My question is, how is the "difficulty" and the odds of finding a block related? Obviously a difficulty of ~4 billion does not mean there's a 1 in 4 billion chance of finding a block (any modern ASIC miner could find a block in a heartbeat). So what does it mean exactly and how does difficulty and odds relate? And how can one calculate the odds based on the difficulty?


texts: How is nSequence interpreted with CHECKSEQUENCEVERIFY?

texts:
I am trying to understand the implementation/specification of OP_CSV with BIP112 and BIP68.
I understand the implication of the op-code and new consensus rules. I just don't understand exactly how the sequence number is represented.

First of all I am not sure what it means when e.g. the type flag of the sequence number is referred to as bit (1 << 22). Does it just mean it is the bit at position 22?

Similarly with the disable flag (1 << 31), is the bit at position 31? And what is its implication? It must be "unset" (=0?) to use the NEW consensus rules for the sequence number? Why is it necessary when the  version field of the transaction > 2 already tells to use the new consensus rule?

I also don't understand this sentence:
"The flag (1<<22) is the highest order bit in a 3-byte signed integer for use in bitcoin scripts as a 3-byte PUSHDATA with OP_CHECKSEQUENCEVERIFY (BIP 112)."
A 3-byte integer has 24 bits, or not? And one bit is used as sign. Then since the flag is the highest order bit, why is it not at position 23?
And why is it represented as a signed integer, when obviously negative block-counts is marked as error by BIP112?

Maybe somebody could give me an example of how exactly the sequence number would look like for the following:

Transaction confirmed with block 400,000 and:
scriptPubKey: "30days" OP_CHECKSEQUENCEVERIFY

Transaction that spends the output:
scriptSig: OP_TRUE
nSequence: ?

Does somebody know how the exact data of "30days" would look like (the bit/byte-wise number represenation with flags and all)?


texts: Searching for EUR exchange with high trading volume

texts:
I'm currently trading on kraken.com which works perfectly fine. Now I want to discover other EUR exchanges which have good reputation, a relatively high trading volume and preferably low trading fees.

I would very much appreciate any suggestions.


texts: Does BTC-E have an API for alternate currencies?

texts:
BTC-E appears to have an API available at https://btc-e.com/api/1/ticker but this only lists the BTC/USD pair data. They also offer pairs of BTC against alternate currencies like Ixcoin and Tenebrix. I've tried the obvious stuff a la https://btc-e.com/api/2/ticker but no dice.

I'll take an API from any other multi-currency exchange as well, really I just need a way to grab price easily from code without having to scrape HTML and deal with regex.


texts: Why is my transaction not getting confirmed and what can I do about it?

texts:
I sent a transaction

without (or with an exceptionally small) transaction fee
using extremely small or unconfirmed inputs
while the stars were not standing right.

For whatever reason, I have been waiting forever for my transaction to confirm.

Why is it taking so long for my transaction to confirm? What can I do to speed-up the transaction’s confirmation?

This is a canonical question serving as a lightning rod for the flood of "unconfirmed transaction" questions we are experiencing lately. Please provide a detailed and broad answer to serve a wide range of these questions.


texts: Are transactions possible when setting up/ sync wallet Qt2

texts:
Hi any help really appreciated..

About 12 months ago I purchased some bit coins from 2 different merchants and began to sync my wallet on Qt 2. Frustrated with tedious progress I put the project on hold, and now have continued to sync, which is still only 88% complete.

My question and dilemma is this. I can't recall in the set up process if I was required to send coins to my own wallet, there are 3 transactions showing 2 received and one sent.. I don't remember if I actually sent coins to someone back then when I was going to purchase a product, I seem to recall the coins I was going to send him somehow weren't yet  in my out of sync wallet…

Is it possible to be sending coins before the wallet is synced ?

So if a new, out of sync wallet is showing coins as having been sent to
an address, could that be to my own wallet due to the set up process ?
that address is listed in the "sent to' tab is there a way to check if its me or where it went ?
Cheers,

Tim


texts: Is support@pi.uk.com the real blockchain.info's support address?

texts:
Currently blockchain.info lists that address in the "about us" page, but since the site is behaving erratically, I wonder if it's the real address or a phony one.

I.e. if the site was hacked, the address would likely be replaced with one the attacker has access to, so the info provided on the site itself is not very useful to determine if that address is genuine.


texts: How to get unconfirmed-transactions count by API

texts:
This site shows counts of unconfirmed transactions.

And there is a API that returns in json format.

https://blockchain.info/ja/unconfirmed-transactions?format=json

But I couldn't find the count in the json.

How can I get the count by using this API?


texts: How could LN mitigate NAT transversal problem?

texts: As we all know, IPv4 address space is already exhausted, many ISPs have deployed carrier grade NAT (CGN). So how could an LN node living behind NAT deal with NAT transversal problem? How could two NATed LN nodes communicate with each other?


texts: Are there any attempts at creating ASIC for bitcoin mining?

texts:
I take reference to the Question here which compares ASIC with FPGA. In this question someone quotes a company called Largecoin that is said to be at the development of such an ASIC. However their web page does not really look promising. It rather looks like some investment seeking attempt. (Quote from the only content on the web page: "For more information about LargeCoin, visit largecoin.com")

I would like to know if there are any other attempts at building ASIC for bitcoin mining?


texts: Polling for transactions -- possible scalability issues?

texts:
We are generating a few thousand addresses by an offline wallet, and plan to run a bitcoind node to check for incoming transfers. The idea is to check an address e.g. every second and get the list of corresponding transactions. So, we're going to have a few thousand RPC calls to our node per second (we cannot check all account-related transactions with one request since the account only exists on our wallet which stays offline for security reasons).

Questions: will it scale well? Has anybody tried sending 1000's requests/second to a bitcoind daemon? Can we send them in parallel?

If anybody can suggest a better way of doing this, please share.


texts: Mutibit HD - Maintain a wallet on 2 devices

texts:
Is it possible 2 maintain a single Multibit HD wallet on two devices? Assume a laptop and phone. My first thought is to install MB HD on the second device and create a new wallet using the original wallet words.
TKS,
Regards,


texts: transaction broadcasts, declining node count, mining basics and costs.

texts:
I read a lot about bitcoins and mining and nodes but there are a few questions that are still not answered, which are the following:

As I read when a transaction is broadcasted, at first it gets confirmed by active nodes and later goes to mempool and miners pick the ones with higher fees. So the question is, when I make a transaction on a website how can I make sure that the website is broadcasting my transaction? Maybe the site is holding it because it has high fee so that he can include it in his own block?
I noticed that nodes are becoming fewer every day , does this mean
when they become less the security of bitcoin or its value will
decrease ?
In order to become a miner, do you have to be a node too?
Btc.com has a crazy fast hash rate. Is it even worth to get into mining?
Say I want to become a miner with a chance of solving at least one block in a month, approximately how much should I invest? And should I buy cloud space or mine on my own?


texts:
Can you call PoW 2f resilient if all nodes would have same hash power?
PoW is called eventually consistence. Even in an asynchronous network.

The only attack possible is 51% attack. Further, there is the selfish-mining issue.

At the end, PoW tolerates up to 50% malicious nodes, if the hash power would be the same? PBFT is only 3f+1 resilient.


texts: Banking partners with UK Faster Payments

texts:
What is the easiest way to have access to UK Faster Payments facilities as a Bitcoin business? The UK banks have been quite hostile.

Can Bitcoin businesses have access to the Faster Payments network in the UK?


texts: What stops a wallet from stealing bitcoins?

texts: I'm not particularly knowledgeable on the topic of cryptocurrencies so it's possible that I've missed something obvious, but I still wonder what it is that stops a wallet from stealing from you. Wallets contain your private keys and they obviously have to use them to be able to send coin. So what stops a given wallet from stealing bitcoin from a user in the background without the user's knowledge?


texts: Does GDAX use its own wallet to send Bitcoin on my behalf?

texts:
I am new to cryptocurrencies and Bitcoin specifically. I recently made a transaction by transferring some Bitcoin from my GDAX wallet to my Binance wallet.

Here is my public key: https://blockchain.info/address/1CQUN1tN1BrD8dPtqFjUeKRGcdYmEhdafh

Why is the sender of the Bitcoin from an address that does not belong to me? I checked my GDAX public key which changes every time I refresh the page.

If you click on the the public key that sent the Bitcoin, it shows that it has made another transaction for 0.98504441 BTC to a different address.

So I have a few questions:

Why does my Bitcoin public address change everytime I refresh the page on GDAX?
Why does the sender of my Bitcoin also have another transaction to a different public key?
Does GDAX send out Bitcoin from a shared wallet on my behalf?

Thanks!


texts: Bitcoinj: How to fix error "You should use Context.propagate() or a ContextPropagatingThreadFactory"

texts:
I'm using bitcoinj from a Scala application... and when I start it, I always get the following errors:

[error] o.b.c.Context - Performing thread fixup: you are accessing bitcoinj via a thread that has not had any context set on it.
[error] o.b.c.Context - This error has been corrected for, but doing this makes your app less robust.
[error] o.b.c.Context - You should use Context.propagate() or a ContextPropagatingThreadFactory.
[error] o.b.c.Context - Please refer to the user guide for more information about this.

To send/receive bitcoins I just use class WalletAppKit as described in github:

...

// init
val walletAppKit = new WalletAppKit(...)
walletAppKit.startAsync
walletAppKit.awaitingRunning
walletAppKit.wallet.addEventListener(new WalletListener)

...

// send coin
val req = Wallet.SendRequest.to(new Address(params, coinAddress), Coin.valueOf(toNanoCoins(amount)))
req.aesKey = wallet.getKeyCrypter.deriveKey(secret)
wallet.sendCoins(req)

...

// listener
class WalletListener extends org.bitcoinj.core.AbstractWalletEventListener {

  override def onCoinsReceived(
    wallet: Wallet,
    transaction: Transaction,
    prevBalance: Coin,
    newBalance: Coin
  ) {
    ...
  }
}

Where should I use Context.propagate to fix this error?


texts: Clarification of lightning network example (putting funds into lightning)

texts:
I'm checking How does the Lightning network work in simple terms? answer example:

  1) Putting funds into Lightning  We both send 0.5 BTC into a shared
  2-of-2 multisig address. This requires a transaction on the Bitcoin
  blockchain.  As a "balance sheet", we each create a 2-of-2 multisig
  transaction that pays out 0.5 BTC to you and 0.5 BTC to me. I sign
  one payout transaction and give it to you. If you want to put it in
  effect, you need only add your own signature and broadcast it to the
  Bitcoin network. Vice versa, you give me your copy of the payout
  transaction that you have signed and I have not yet. The "balance
  sheet" is a regular 2-of-2 multisig transaction in the Bitcoin
  network, it just isn't valid yet, because it doesn't have all
  signatures.

So in the first step you make a regular transaction from your address A to our common 2-2 address C, and I make a regular transaction from my address B to our common 2-2 address C?

I have one key of this 2-2 multisig address C and you have another?

Address C now has 1BTC.

Now from this address C I return 0.5 of its 1 BTC to your address A and sign with my key, and you return remaining 0.5 to my address B and sign with your key?


texts:
Bitcoin testnet

I used the following code to obtain info about unspent outputs:

const blockchainInfo = require('blockchain.info')

const blockexplorer = blockchainInfo.blockexplorer.usingNetwork(3)
blockexplorer.getUnspentOutputs(address).then((resp) => {
  console.log(resp.unspent_outputs);
})

Response:

   [ { tx_hash: '9c5a...f31b',
       tx_hash_big_endian: '1bf3....5a9c',
       tx_index: 249487365,
       tx_output_n: 0,
       script: '76a9...88ac',
       value: 200000000,
       value_hex: '0bebc200',
       confirmations: 2262 },
     { tx_hash: '708e...ec103',
       tx_hash_big_endian: '03c1...8e70',
       tx_index: 250637325,
       tx_output_n: 0,
       script: '76a9...88ac',
       value: 20000,
       value_hex: '4e20',
       confirmations: 1845 },
     { tx_hash: '803a...901d',
       tx_hash_big_endian: '1d90...3a80',
       tx_index: 256201920,
       tx_output_n: 0,
       script: '76a9...88ac',
       value: 20000,
       value_hex: '4e20',
       confirmations: 262 },
     { tx_hash: '255d...cfde',
       tx_hash_big_endian: 'decf...5d25',
       tx_index: 256264533,
       tx_output_n: 0,
       script: '76a9....88ac',
       value: 20000,
       value_hex: '4e20',
       confirmations: 252 } ]

And I got some questions.

Why do we have both tx_hash and tx_hash_big_endian? Because some wallets prefer big-endian and others little-endian hash?
What is the tx_index? Index of a transaction in entire blockchain?
What is the tx_output_n?
What is the script?


texts: Installed 2nd Bitcoin client and invalidated blockchain progress

texts:
over the last couple of days I synchronized the block chain on an old version of Bitcoin QT where I still had funds in my wallet. It started out 90 weeks behind, then over the course of 4 days updated until it had 23 more weeks to go. At this point any progress stopped, seemingly getting stuck for 24 hours or longer and I couldn't find a solution to make it continue its synchronization.

I then installed Unlimited Bitcoin since I heard that new clients would synchronize much faster. I assumed that both clients would build their block chain separately from each other but the Unlimited Bitcoin installation corrupted any progress that Bitcoin QT had made and upon starting it the next time, it had to re-synchronize now being more than 200 weeks behind.

Unlimited Bitcoin however seems to refer to QT's progress status, also being 200+ weeks behind and not updating any quicker.

What would be the fastest way to get the blockchain up to date on my hard drive in a way that the funds on my QT wallet can be used?

Thanks in advance.


texts: Would quantum computing be able to deanonymize CoinJoin transactions?

texts:
Using the worst case scenario of this question, namely:

  Bitcoin ECDSA algorithm would be broken. Because quantum computers can easily decrypt the private key using the public key, anyone with a quantum computer can extract Bitcoins using the corresponding public key.

Given that quantum computers would be able to obtain private keys, would they be able to deanonymize CoinJoin transactions that are already present in the blockchain?


texts:
I am running "./bitcoind -daemon -gen" in my machine . Is it solo mining ? If so, what does it take to create 1 bitcoin ? When i run "./bitcoind getbalance" it is always 0.00000 .
"./bitecoind getmininginfo" results in:
{
    "blocks" : 319203,
    "currentblocksize" : 1000,
    "currentblocktx" : 0,
    "difficulty" : 68.59413778,
    "errors" : "",
    "generate" : true,
    "genproclimit" : -1,
    "hashespersec" : 1447,
    "networkhashps" : 2298081699,
    "pooledtx" : 0,
    "testnet" : false
}

Am i on right way ? If so, what does it take to create 1 coin ? Also, when i create a coin, how to send it to my address ? will it be automatically ?


texts: Where can one download Bitcoin Days Destroyed data? Alternately where to get data to calculate BDD?

texts:
I'm trying to find a source of downloadable (preferably csv) data for Bitcoin Days Destroyed. Alternately I can calculate it myself provided I can find the constituent data.

In particular, I want to calculate dormancy which is total number of days destroyed  divided by volume. I know the total number of days destroyed is the value of the transaction multiplied by the number of days since that BTC was last moved.

Where can I find either data that has already been calculated for dormancy, or data on days destroyed, or barring either of those, the number of days since the last transaction for each Bitcoin?


texts:
We can get a transaction input and output from online exporter.
https://blockexplorer.one/btc/testnet/tx/302e26291733910e0312ce1794f521a8303888a9575e8460dec53018e2233e18
But I can't directly get same data in the bitcoin-core node
bitcoin-core.cli gettransaction 302e26291733910e0312ce1794f521a8303888a9575e8460dec53018e2233e18 true

response: https://gist.github.com/XiaoXiaoSN/a781633c462b53a5646d545dc41391ab
I tried to use tricky steps to get transaction results
# use transaction hex to get vout
# response: https://gist.github.com/XiaoXiaoSN/89ca1699ef55cbbe65cf03bbe5ce8b31
bitcoin-core.cli getrawtransaction 302e26291733910e0312ce1794f521a8303888a9575e8460dec53018e2233e18 true

# use vin[].txid and vin[].vout to lookup the unspent transaction
# response: https://gist.github.com/XiaoXiaoSN/dd38dd8206ac277834771d98dee3fca4
bitcoin-core.cli getrawtransaction 8e379596692962086346088d2756c5ebd7515104f1a3ee2cc1c2b15c3c07b4e9 true

Is there any sample way to get the transaction details by txid?
version
Bitcoin Core RPC client version v0.20.1


texts: What is the longest time a transaction has been in limbo for?

texts: What is the longest time a transaction has been in limbo for in Bitcoin?


texts: How does a Doge public key is created from a private key?

texts:
I am looking for the differences between the creation of Doge public keys and Bitcoin public keys when inserting a private key.

I am trying to make a small web-app that signs messages. There are a tons of them with bitcoin. They receive a private key and creates the public key from there. When I enter a Doge private key to the input the output is still a Bitcoin public key (Starts with 1 for example instead of D).


texts: Whats the easiest way to go from BTC to GBP? Paypal solution?

texts: Is there anyway of being able to transfer bitcoins to pound sterling to a paypal account at all? I struggle to find any solutions in this area so that I can make regular conversions. Even just to a UK bankaccount is ok, but Paypal is prefered? even if it means getting small fees as one would expect.


texts: Electrum + Trezor - Rename address labels only allows one label to be defined

texts:
Using Electrum 2.3.3 on Ubuntu 14.04.2 with a Trezor (firmware 1.3.3), I'm having trouble with the account labels.

When I rename an account, it displays the new label. However, when I rename another account, the first one I renamed goes back to being "Account 1". It doesn't seem to retain my changes.

Thanks for any help you can provide, and let me know if more information is needed.


texts:
From having a list of bip39 seeds, is there any way of recovering a wallet?  In particular, I have a list of ~100 seeds--one of which is mine--and need an automate way of figuring out which is valid and has my funds.
Thanks


texts:
I used to be interested in Bitcoin a few years ago and have recently become aware of it again. I used to have a wallet back then. Given that many years have passed, what I remember is a bit fuzzy. What can I do if…

I don't remember which service I used
my wallet service shut down
I lost access to my wallet service account
I removed the wallet from my computer or phone and have no backup
I had a wallet, and still have the device that it was installed on

If your question is not covered here, please ask a new question, explaining how your situation differs from the topics collected here.

This is intended to form a canonical question to act as a lightning rod for the flood of lost wallet questions we have been receiving lately. Please contribute additional answers to help make it as useful as possible.


texts: How does an SPV node verify an unconfirmed transaction?

texts:
Alice pays Bob 1 BTC with a simple pay-to-address type transaction. Three seconds after Alice broadcasts her transaction, Bob's Simplified Payment Verification (SPV) wallet displays a message saying the transaction was received.

How exactly does this work? What checks, if any, does Bob's wallet do before showing the message?

A lot of the SPV documentation I've seen makes vague statements about "height" vs. "depth" verification. These discussions aren't helpful because they don't describe the actual process.

The clearest statement I've found appears on the BitcoinJ documentation (under "Pending transactions"):

  ... However, in SPV mode the only reason you have to believe the transaction is valid is the fact that the nodes you connected to relayed the transaction. If an attacker could ensure you were connected to his nodes, this would mean they could feed you a transaction that was completely invalid (spent non-existing money), and it would still be accepted as if it was valid.

https://bitcoinj.github.io/security-model

In other words, complete trust is placed in the network to only relay valid transactions. The network isn't supposed to relay double spends or transactions spending bogus coins. Therefore, the relay, and only the relay, vouches for the validity of the unconfirmed transaction. If an attacker can control your internet connection (through a WiFi hotspot, or VPN, for example), then he can send you fake unconfirmed transactions and rip you off.

Is this how SPV nodes handle unconfirmed transactions?

It seems like an SPV node could do better. For example, couldn't Bob's wallet verify that the coins being spent existed at one time? Request the Merkle path and transaction for all outpoints referenced in the unconfirmed transaction's input list. If the parent transactions can't be found, Alice's transaction is trying to spend bogus coins.

Could a similar mechanism be used to further verify that Alice's unconfirmed transaction doesn't double spend coins?

If neither of these checks are possible today, what would need to happen for them to become possible?


texts: Does getting shares when mining mean that I have earned a reward?

texts: So I have 13 Total Shares (Non Rejected) and my pool is Mining Pool Hub. It does not show that I have gained any Ethereum when I go to Dashboard (Under Ethereum) on Mining Pool Hub. Do accepted shares mean that I earned coin or no?


texts: How to get destination address from bitcoinj TransactionOutput?

texts:
I believe TransactionOutput represents one of the outputs of a transaction.

I have a list of such output objects, and a String that represents my own address. I would like to check that this output reached my address.

How do I get the destination address from the TransactionOutput object?


texts: How to verify Wrapped Bitcoin (WBTC) issuance

texts:
I'm trying to understand how Wrapped Bitcoin (WBTC) issuance can be verified.
The WBTC custodian, BitGo, published the following material:
https://wbtc.network/dashboard/audit
This is a list of Bitcoin addresses linked to Blockstream explorer where you can verify the UTXOs each address has access to (wallet balances, if you will). The sum total of these balances is equal to the amount of WBTC minted by BitGo.
However, how do I know that BitGo has the private keys for those UTXOs? Am I supposed to just accept the bonafides of BitGo and their audits, or is the a technical way to remove that trust?


texts: Taxes when selling products/services in bitcoin

texts:
If I sell products/services in bitcoins, do I need to convert them to dollar (or the local currency) always? Or it's ok to charge in Bitcoin and fill the invoice in BTC (and/or with the conversion to local currency) but keep the payment in BTC?
Or we need to always convert them to local currency and leave the registry of that transaction in some bank of our company etc?
// Sorry if it's duplicate because I think this must be a common question but I'm not finding the answers.


texts: How do I disable automatic address generation for the official bitcoin client?

texts:
This question was asked before over at bitcointalk.org over here way back in June '11. The answer back then was a resounding no. Is this still the case?

My wallet.dat keeps growing bigger after every transaction since the client keeps generating and adding new bitcoin addresses I never intend to use. I want to stop that from happening.


texts:
I've followed the tutorial provided in this answer:

How do I access information on blockexplorer.com or blockchain.info without issuing requests to those websites?

But there aren't any instructions on how to get and run bitcoind first as Abe requires the genesis blocks.

In addition, I am getting the following error when trying to synchronize:

$ python -m Abe.abe --config=abe-sqlite.conf --commit-bytes 100000 --no-serve

failed to load /home/bitcoin/.bitcoin/bitcoin.conf: [Errno 2] No such file or directory: u'/home/bitcoin/.bitcoin/bitcoin.conf'
catch_up_rpc: abort

I have bitcoind installed on my ubuntu server:

$ sudo apt-get update
$ sudo apt-get install bitcoind
$ bitcoind

What should I put in my config file? What else does Abe require from bitcoind?


texts: Is it possible to autoforward bitcoins to another address?

texts:
we would like to accept BTC for our token sale. In order to achieve that, we need a specific BTC address for every contributor.

The contribution flow is:
- investor sends BTC to their dedicated address
- the contribution is recorded in an offchain database
- the BTC is forwarded to a central account

as I don't know if this is even possible, some pointers would be highly appreciated.


texts: Saved .bitcoin directory full ~9 GB block data, won't work when copied to another system

texts:
I had to delete my .bitcoin directory in Ubuntu 12.10, after months of getting the near 9 GB of blk data files.

I copied everything over to another machine (and back to the original too) and it gives me:

  A fatal error occurred. Bitcoin can no longer continue safely and will quit.

     EXCEPTION: St13runtime_error
     CDB() : can't open database file blkindex.dat, error 22
     bitcoin in Runaway exception

I tried chmod +w on the files, but still no go.


texts:
A friend presented me the concept of antifragile and asked me if Bitcoin is antifragile. I couldn't answer properly, so I'm asking the experts:

Can bitcoin be categorized as antifragile?


texts: Why Do Compact Signatures Need To Start With a Byte 27-35?

texts:
There's a hard-coded 27 value in Bitcoin's encoding of Compact Signatures that I don't understand:

https://github.com/bitcoin/bitcoin/blob/v0.7.1/src/key.cpp#L333

I get that the need to encode the nRecId to disambiguate the correct recovered key, but I don't understand the 27 (or for that matter why fCompressedPubKey is encoded as a 4).

The decoder requires the first byte be between 27 and 35, but then just subtracts the hard-coded 27 sans explanation.

It this poor man's bitmasking? It there something in the protocol that Compact Signature's can't begin with a 0x00 and this is a weird work-around? Perhaps it's acting as a sort of magic cookie?


texts:
I recently setup a bitcoin node (bitcoind) and lightning node (lnd) on a linux system. As lifetime windows user this was quite challenging!
Anyway I tried to open my first channel about 4 days ago and the transaction is still stuck in pending. I didnt set a fee manually as I had read that lnd should automatically pick one. I cant find a TXid to lookup what fee was chosen.
Is there a way I can bump up the fee or do I have to wait until it drops out of the mempool?
Next time how can I check what fee will be set and possibly adjust?
Thanks.


texts: How can I pay someone in another country?

texts:
I have my wallet with some BTC in it, on my PC, and I live in europe. Let's say I want to pay 2BTC to a company in India or China, or whatever, but they don't accept BTC. They only take Indian Rupees (INR) or Chinese Yuan (CNY).

Now my question: is there any way to send BTC to their country, then those BTC become Rupees, and these workers can just walk to their bank to get their money? Or some other easy way to pay them without fees or at least the smallest fees possible?

Thanks!


texts: Subscribe for market depth updates using Mt.Gox streaming API

texts:
I want to subscribe to market depth updates using the streaming API https://en.bitcoin.it/wiki/MtGox/API/Streaming. I want to receive only depth updates for a particular symbol (EUR for example) or for all symbols.  So I connect to wss://websocket.mtgox.com and send the command

{
     "type": "depth",
     "op": "mtgox.subscribe"
}

I'm expecting to receive depth updates for all symbols. But it sends me updates only for BTCUSD. Though the same subscribe command with parameter "type" = "trades" sends trades for all symbols (not only BTCUSD). That's a little confusing.

The currency parameter is mentioned in API documentation: websocket.mtgox.com:80/mtgox?Currency=EUR, but after connecting to this websocket I receive ticker updates as well. But I don't need ticker updates.

The question is how can I receive only market depth updates for particular symbol? (or all of symbols)


texts: Does one need to have a bitcoin wallet to buy/sell bitcoins?

texts: There appears to be so many exchanges / middle-mans on a bitcoin market (e.g coinjar.com) which can help to buy / sell bitcoin for a cut (usually 2-4%). Do they simply trade bitcoins using their own bitcoin wallet and just keep the client's balance of cash/bitcoins in their system?


texts: How much data is transferred using Andreas Schildbach's Bitcoin Wallet Android app?

texts:
After installing the app, a message appeared on my phone saying there were 83 weeks of data to synchronise. How much data is involved in this process? I don't want to exceed the data limit for my phone.

Also, 14 peers appear to be connected. While the app remains open in the background, how much data does connecting to peers require over time?

A comment against the app in the Play store says:

  During the last 4 weeks, Bitcoin Wallet has consumed 166 MB of my data
  plan, 160 MB of which was running in the background. I am pretty sure
  that I had once set it to only transfer data in background when Wifi
  is on and it had been running smoothly like that for about 1 year. For
  now, I turned of "Sync on Power" and I hope this helps for now. But I
  think you should re-introduce the "background sync only on wifi"
  setting.

That gives some idea of the quantities of data, but it doesn't split it into what's required for the initial synch and the ongoing connection, so my question still applies.


texts:
Can anyone please explain the code below with comments?

What are pbegin & pend ?

What is ( I believe it is data, where it comes from ?): (pbegin == pend ? pblank : static_cast<const void*>(&pbegin[0]))

What is (I believe it is the size of data 80?) : (pend - pbegin) * sizeof(pbegin[0])

What is : pblank[1]

template<typename T1>
inline uint256 HashShabal(const T1 pbegin, const T1 pend)
{
    sph_shabal256_context ctx_shabal;
    static unsigned char pblank[1];
    uint256 hash[1];
    sph_shabal256_init(&ctx_shabal);
    // ZSHABAL;
    sph_shabal256 (&ctx_shabal, (pbegin == pend ? pblank : static_cast<const void*>(&pbegin[0])), (pend - pbegin) * sizeof(pbegin[0]));
    sph_shabal256_close(&ctx_shabal, static_cast<void*>(&hash[0]));

    return hash[0];
}


texts: Bitcoin-Qt icon not showing in Top Edge Panel (Linux Mint)

texts:
I've been using Bitcoin-Qt (now 0.6.2) for two months now with no problems. Now its icon is missing from my top edge panel (Gnome Desktop, Linux Mint 64 bit). How do I get it back? Or is there any other way to open the GUI window?

Restarting the system doesn't help.

I'm new to Linux (used Windows before, but used bitcoin on Linux only).

The bitcoin-qt client is running as I can see the process in System Monitor and also the log file keeps updating. (I don't see any apparent errors in the log.) The bitcoin-qt process starts automatically on system restart.

If I try to start bitcoin-qt, I get the message that it can't obtain a lock and that it is probably already running (which it is). The .lock file (0 bytes) is present in ~/.bitcoin.

What I can do is I can stop the bitcoin-qt process (using System Monitor) and then start it manually and then everything is fine. But after restarting the system, the problem is back.

Any ideas? Should I post more info (which?)? Thanks!


texts: Need help on building transaction with go(lang)

texts:
i try to send a transaction to bitcoin testnet for about 3 days now but i can't success... Probably someone can help and give me some example code.

What i try to do:

I'm writing some payment functionality in the stellar network, where people can pay with btc. Therefore i generate a bitcoin address/WIF and save this in my db.

I then please the customer to pay on this address. I check all transactions from the bitcoin network and when i get a payment on this address i want to either move the btc to some other btc-address or refund the amount (minus fee) to the source btc-address.

I'm running a full node (https://hub.docker.com/r/kylemanna/bitcoind/) and checking the transaction works great.

But for the transfers i'm stuck somehow. I'm new to bitcoin, so this might probably be the  reason ...

I'm building the service with go(lang) and using the https://github.com/btcsuite so far. I'm connecting via rpcclient.

The only resources i found on the web for this is:
https://www.thepolyglotdeveloper.com/2018/03/create-sign-bitcoin-transactions-golang/

Till now i tried the following UTXO:
f3a38acecbd9faaaebc8cb8fd88cb535388060f35923b60e6a7f185b4bb35a4f

(https://live.blockcypher.com/btc-testnet/tx/f3a38acecbd9faaaebc8cb8fd88cb535388060f35923b60e6a7f185b4bb35a4f/)

The WIF-String for "n18HgZaBAT3r7PmdLE6jxxHUCQbi65neiQ" is "cNtsnL67rYr3r2nX6vyZrDrBGk4cKbvcMKS6wmfnzRwCCYiA4Soj"

The signed transaction i created so far are all valid and i can paste them into https://live.blockcypher.com/btc-testnet/pushtx/ but i always get an error that there's a missing reference for the transactions. My docker-node returns "Missing inputs".

If someone could give some complete example, on how to create this transaction, i would be very very happy.

Many thanks.


texts: How to restore wallet from 15-word seed mnemonic?

texts:
The wallet was created around Feb 2013, using unknown wallet software. All that is known is a passprase, and 15 words. I suspect the passphrase was used to encrypt the wallet, and is probably irrelevant here, since the wallet file itself is lost.

All words are found in the "old" Electrum list. But the number 15 is puzzling, since no version of Electrum ever produced 15 words by default, as far as I know. I considered the possibility that this mnemonic was extended with custom words, but it looks like custom words in Electrum work only with the "new" word list.

I cloned Electrum repository from github and tried converting mnemonic to hex seed using the old list, then converting it back to mnemonic using the "new" word list. This method produces 15 words that Electrum GUI does recognize as 12 + 3 (extended), but leads to empty wallet.

My working hypothesis: there ought to be another wallet software that existed around 2013 that used Electrum's "old" word list and generated 15 words by default. Any other ideas or suggestions?


texts: Integrating bitcoin with php to accept donations

texts:
i have a blog and now i want to integrate bitcoin using php so that i'm able to accept donations or charity.

But i don't want any 3rd party processing like for creating qr code or invoices or content like that.
Is this possible or if not can someone point me in the direction of a proper integration method even if its 3rd party.


texts: Can pharmaceutical products be returned or sold to other customers using bitcoin as a form of payment if I was the seller. I am wondering because I am a pharmacist and have a lot of overstock and was wondering if other less fortunate people in the world could benefit from use of medication still in date.


texts: Can 2 bitcoin-cli's use the same blocksdir

texts: I am trying to set up 2 clients with both using the same block directory is this possible?


texts: What is the fee policy suggested by the mainline bitcoin client?

texts:
The online wallet blockchain.info allows for the fee policy to be customised:

The "Normal" policy states

Follow the fee policy suggested by the mainline bitcoin client.

What is the fee policy suggested by the mainline bitcoin client explicitly?


texts:
I have a R9 280x Toxic edititon and I've set up cgminer with latest catalyst on ubuntu 12.04.3

the thing is, if I run cg miner like

cgminer --scrypt  -o stratum+tcp://url:3333 -u a.b -p c -I 13 -g 2 -w 256 --shaders 4096

It does not accept anything - A:0   R:0   even after a few minutes

If I run it with - shaders reduced by half

cgminer --scrypt  -o stratum+tcp://url:3333 -u a.b -p c -I 13 -g 2 -w 256 --shaders 2048

it will start accepting almost immediately.

the problem is, with 2048 shaders my hash rate is 480 kH/s, but with 4096 shaders I get up to 770 kH/s


texts: Does an incorrect preimage cause intermediary nodes to discard a Lightning payment?

texts: Consider a multi-hop Lightning payment from Alice via Bob to Charlie. Charlie creates an invoice, Alice finds a route and forwards the payment, now Charlie is expected to redeem the payment by revealing the preimage to Bob. If Charlie tries to redeem the payment using an incorrect preimage, does Bob cancel the payment altogether, or does Charlie get "a second chance" to redeem it?


texts:
Hey my name is Philip and i would like to setup a bitcoin miner.

I am working on a school with loads of older pc's that i thought to be fun to set up for mining bitcoins, and i'm asking if it would be possible.

It is a lot of older hp pre built office pc's with no gpu's.

I want to do it for the experience of setting it up and don't expect to make any profit at all.


texts:
As some of you recall, we had the BTC ZCL fork this year. For those who had the ZCL on the Bittrex wallet, they were convert to BTCP, but Bittrex wasn´t trading, but it was allow to keep those tokens on the wallet.
Due to the market down, I left my tokens on bittrex wallet, hopping one day would trade BTCP.
Yesterday I find out that all my tokens were lost. Bittrex canceled all the wallets. All this was done with no warning, at least I didn’t got one. It´s amazing the amount of mail trash that we get from these exchanges and the important things are take like this. In Bittrex defense, they say that, an email was sent. We are talking about money here...keeping your money it´s not something that you inform over email, or you have to make sure that everyone got the message. Imagine if your bank does that, it would be his last day.
I think this is the kind of attitude that makes crypto a joke to general people and undervalued.
Where can I press charge, or report this in europe?
To be honest as you imagine I did not had many tokens (otherwise I would keep then on a wallet), but is still money. The worst thing here is attitude, it was very disappointing.


texts: What is Valgrind? When should I use it for debugging Bitcoin Core over using gdb, lldb, pdb etc?

texts: I was watching Fabian Jahr's presentation on debugging Bitcoin Core at Bitcoin Edge Dev++ 2019. He mentioned Valgrind briefly at the end. What is it and when should I use it over gdb, lldb, pdb etc?


texts: How exactly can I generate a transaction id?

texts:
I'd like to create a transaction object from scratch. I've read that the tx id for a transaction is the double SHA-256 hash of a serialized transaction, but havent been able to find details on exactly how the data is formatted before its serialized or how it is serialized for that matter.

Could someone, perhaps, provide an example of how the data is organized before it's serialized and/or describe the manner of serialization taking place?


texts: Which cryptocurrency server software supports the walletnotify feature?

texts:
I am looking to build a realtime service for crypto payments and would like to know which currencies are based on server software that supports "walletnotify" out of the box in the way Bitcoin does - specify the script to run on payment received and confirmed.

Am I correct to assume BCH, BCG and LTC support this since they are forks of the Bitcoin code?

What are other cryptocurrencies I should look at?


texts: Are private keys published to the blockchain after spending coins from a wallet?

texts: Always I spend coins the final balance of the address that is used for transaction will go to zero. The remaining coins comes back as a change to a new address. Will this indicate that the private key of the spending address is published now to the block chain for validation? Is it a risk to use this address furthermore for receiving and storing coins?


texts:
I just started using sgminer but ran into some issues trying to get it to run correctly. Upon running my bat file I get an error saying: 'No login credentails supplied for hash-to-coins.com'. Below are my config and bat files with the worker name/password faked. If I run without the config file the miner recognizes the 9790m but will still fail to connect to the stratum. Any help is appreciated, I've been trying to fix this for several days now.

bat:

Config:


texts: Can I use Bitcoin elsewhere except in the deep web?

texts: I really like the idea of having an universal online currency and I wanted to know if I can use it in the 'surface web'.


texts:
I have an Ubuntu 14.04 512Mb RAM/100Gb HDD server which I use to host a remote bitcoin node. bitcoind currently catches up and for some reason it just stops working after 10-20 minutes or so every time I re-launch it. Nothing interesting in debug.log:

2015-01-11 04:28:47 UpdateTip: new best=000000000000000027ce5c42b2e4b3e5cc51f441aaf3644a4fe8bf0215abae7c  height=306691  log2_work=79.261277  tx=41024325  date=2014-06-19 19:10:49 progress=0.488913
2015-01-11 04:28:47 ProcessBlock: ACCEPTED
2015-01-11 04:28:47 ProcessBlock: ORPHAN BLOCK 290, prev=00000000000000003de1051078cb951cadb90aad2e1a94019df07d431384934e
// nothing here, bitcoind not working anymore

What's going on and how can I fix it?

UPD here's the bitcoin-cli getinfo output:

{
    "version" : 90300,
    "protocolversion" : 70002,
    "blocks" : 306754,
    "timeoffset" : 0,
    "connections" : 10,
    "proxy" : "",
    "difficulty" : 13462580114.52533913,
    "testnet" : false,
    "paytxfee" : 0.00000000,
    "relayfee" : 0.00001000,
    "errors" : ""
}


texts: How much would it cost for a government to undermine Bitcoins?

texts:
Articles by for example the Economist stating that Bitcoins are being used for drug trading (Silk Road), I believe that the biggest risk to Bitcoins is that a government will pull a stunt similar to Stuxnet. This was also the answer of David Schwartz to a previous question of mine.

Therefore, I believe that we should make a metric, similar to Bus Factor for software projects, which indicates risk of such an event with a single number. I propose that the metric should be called CSU (Cost of Secret Undermining). Later we could calculate the cost of undermining in other ways, like by banning businesses that accept bitcoins and so on, but that will be much harder.

Therefore, my question is: What is the current lowest CSU (Cost of Secret Undermining). This means, what is the cheapest way for someone (for example a government) to secretly undermine Bitcoins to the extent that Bitcoins are no longer useful as a medium of exchange, for example by utilizing the method suggested by David Schwartz. We should compare the number that we find with the current budget of the US fight against illegal drugs. Of course, the expected impact on the fight against illegal drugs is a deciding factor. Even though it will be very hard, we should try to estimate the development time needed to launch such an attack as this will be a cost the attacker would have to calculate with.

This question is related to this question, but now I would like to know the cost of undermining Bitcoins instead of just launching one single 51% attack.


texts: Difference between wallet and mining software?

texts: What's the core difference between the mining and wallet software out there? I haven't been able to find any information on this so anything - technical or non is appreciated. Though I'm talking about the wallets that make you download the block chain as well, not the light wallets. Thank you.


texts: what is the Volume and BaseVolume reported from bittrex API?

texts:
For example in https://bittrex.com/api/v1.1/public/getmarketsummaries or if you subscribe to the ws feed you get sent the following type thing.

{
  "MarketName": "BTC-ANS",
  "High": 0.0031,
  "Low": 0.00248777,
  "Volume": 1141826.57957173,
  "Last": 0.00295907,
  "BaseVolume": 3316.06464979,
  "TimeStamp": "2017-08-02T10:54:39.273",
  "Bid": 0.00295907,
  "Ask": 0.00296061,
  "OpenBuyOrders": 2439,
  "OpenSellOrders": 6856,
  "PrevDay": 0.00259698,
  "Created": "2016-10-26T01:28:31.96"
}

What does volume and BaseVolume equal though.. volume traded over last 24h ? The value goes up and down so bit confused. Anyone know ?

If you look at a coin here https://bittrex.com/Market/Index?MarketName=BTC-DGB the v which i assume is volume always seems to be really low.


texts: How to connect to bitcoind from ruby rpc client?

texts: I have started bitcoind. It is working fine but how can I connect to it from rails on localhost?


texts:
I want to sign a file (a picture of 1.4 Mb) with my Ardor Account, in order to have a timestamped proof of ownership.
I tried the generateFileToken API, but it seems to work just with smaller files (no more than 40 kb).
How could I do it?


texts: how to get the private key for an used address ?

texts: I have used an address generated by Exodus wallet. whats happened is that my bitcoin confirmed but didn't receive any thing on Exodus wallet. I want now to import private key in another wallet. but when I export private key in Exodus wallet so there is no private key for the address I have used. the private keys only for new generated adresses. any one have got through such thing ?? any one have an idea how to get private key for used address ? it looks like that I had to export private key for the address before I use it. because it looks like that the private key disappear with the address after using ? is that true ? any explanation ?


texts: What is the meaning of the term "unspent output" in the Bitcoin protocol?


texts:
I captured bitcoin protocol communication in real-time and it is present in fig1 and fig2.

Fig1

In red box, there are many types of command.
First Question:

  How can Wireshark detect bitcoin communication and parse them? I think
  the packet that socket sends may have something what I don't know.

In red box of fig2, you can see many properties of packet. this is definitely defined by software program, not hardware such as router. Real data that client send is really just hex data which is encoded by specific rule.

Second Question:

  How Wireshark can parse data received? Bitcoin client can parse it because they know the rule but Wireshark doesn't know anything since Wireshark is thrid-party program, which no have any relation with Bitcoin software.

Fig2

Sorry for my English.


texts: What's a good site to see bid/ask walls?

texts:
I'm currently using Mtgoxlive to view ask and bid walls.

But ... I can't see the chart beyond about $1.5 +- the current price.

Is there another site for viewing ask/bid walls graphically, in a similar fashion to Mtgoxlive, that is limiting in the displayed data?

Also, a nice to have would be historic wall data. There is the Wall Observer Thread ... is there another site that does this?


texts: How can you share a plaintext bitcoin address private key with a friend and ensure they won’t spend your bitcoin?


texts:
If someone wanted to buy up lots of ripples, say a million, how would they go about doing it?

Currently the exchanges don't seem to give good rates, and trading one-to-one with someone else would be inefficient. Is OpenCoin selling directly? At the current Bitstamp rate, it would cost $4444.44 to buy 1,000,000 XRP.


texts: How do I run the bitcoin bx tool in my terminal

texts: I am reading the book Mastering Bitcoin. At some point, I came accross the bx command and tried to run it in the same way as bitcoin-cli (I've got a bitcoin core node running). But I just get the command not found message. How should I go about it?


texts: How can I reduce the time until I get the newest block ? Does the number of the outbound peers affect the speed?

texts:
I am running a full node on the Bitcoin network. Sometimes, I find that it takes a while until I get the newest block.
I checked the source code, and found that every node can at most connect to eight peers. Would it help to increase the number of connections, to reduce the time until I receive the newest block?


texts: What incentivizes non-miner nodes to propagate transactions?

texts: I know miners are incentivized to verify and propagate transactions for their own benefit (by hopefully publishing it on their block before other miners do). But when a transaction is initially created, e.g. from a wallet that happens to only share a single (non-miner) peer, what incentive does this node have for propagation of the transaction to the rest of the network? Especially since the majority of the network is composed of non-mining nodes, where does this implied trust that they will reliably flood to all known neighbors come from?


texts: How to get Bittrex Commission Value from API

texts:
Binance has a very simple way of getting the Commission value from its exchangeInfo endpoint.

I do not see any corresponding way to get the commission on Bittrex from the API documentation, but it is relatively poor documentation and only covers v1.1

Does anyone know how to get the Commission value from the API?

(Note, I know the current value is 0.25%, which is currently hardcoded into my scripts. I'd prefer to fetch the current value in case it changes rather than rely on hardcoding the value.)


texts: I'm a bitcoin newbie and think that I am missing something.  I'm based in Australia although I'm not sure if that matters.  I would like to buy and hold for an extended period some bitcoin and ether.  I would prefer not to use the exchange's wallet or storage.  Will I be charged a fee to withdrawl and use my own cold storage?


texts: I am working with a cryptocurrency which is a fork of bitcoin. In my blockexplorer it shows 91% synced and I cant see any latest blocks.


texts: Where to stop key derivation when looking at balance of a deterministic wallet

texts:
If I want to know the total balance in all the addresses which can be generated in a deterministic wallet (like electrum or armory).

I have the master public key allowing me to derive an infinite number of public keys.

What is the number of addresses I should generate to check the balance ?

I suppose I can stop if the last X addresses don't have any transactions.

What is the value of X for electrum and armory (when recovering from a backup) ?


texts: How does one manage the shifts of Channel Balances in the Lightning Network

texts:
I saw the video below that shows the possibility of a shift in Channel Balances. It shows that the amount that one uses to fund a channel may "disappear" if the channel is used as part of a route to fulfill the payment for someone else.

Someone Else --> Me --> Store

https://youtu.be/pOZaLbUUZUs?t=2m18s

It this scenario:

-> I get ready to go to the store
-> I establish a payment channel between myself and the store and add $100 USD to it
-> Someone else uses my channel (i.e. me) as part of their payment routing - a go-between - to pay the same store (since they don't have
a direct channel to the store).
-> My direct channel to the store is now empty of funds.

How does one come about this problem?

TIA


texts:
I hope you’re all doing well during this COVID-19 period.
I was wondering how you can calculate the difficulty rate of a coin (Mining purposes)?


texts: What is currently the fastest way to buy a large amount Bitcoin?

texts:
I want to purchase on the order of $10k of Bitcoin in USD. I can't seem to a find a way of accomplishing this in less time than multiple weeks.

I've been looking at the major exchanges, and it seems to be bad news all around.

Mt.Gox requires you to verify your account before allowing incoming wire transfers. This could take 5 days. Then you are required to wait at least 5 business days for it to be processed, then wait an unspecified period for their AML checks to be completed.

Other exchanges I've looked at (such as btc-e, bitfloor, etc) allow incoming wire transfers, however don't specify how long the processing should take.

What is the quickest way I could theoretically accomplish this?


texts: How can I transfer all funds to new keys?

texts:
My wallet.dat (bitcoin-3.4) has maybe been left on a work machine, leaving it accessible to the admins there.

I would like to transfer all my current funds to a new wallet. How do I do this and how can I make sure that:

I still will be able to receive on the old keys (in case someone sends something there)
Not all my funds are transferred to the same key, making me more traceable.


texts: Why are 0.13.1 Core nodes connecting only to Witness (e.g. 0.13.1) nodes?

texts:
I have my Core 0.13.1 node configured to connect to 16 nodes, and invariably I see it connected only to other 0.13.1 nodes, even though, according to bitnodes leaderboard, these nodes form a minority.

Why is the selection logic this restrictive?

I am also noticing my 0.13.1 node that accepts incoming connecting as relatively overloaded I/O-wise since it upgraded.

I can understand this selection logic being necessary once SegWit activates, but why already, given we don't know yet whether SegWit will activate?

Related: https://github.com/bitcoin/bitcoin/issues/9072


texts: How to getreceivedbyaddress() with the python-bitcoinlib?

texts:
I'm trying to use the python-bitcoinlib in my bitcoin project. I now understand how I can send a payment, but I can't find anything similar to the getreceivedbyaddress() command I normally used.

Isn't it present in the python-bitcoinlib, is there a workaround, or am I simply overlooking something? All tips are welcome!


texts: How to get input address and amount from vin using bitcoin core rpc


texts: How do I transfer BTC from my Coinbase account to my Android wallet?

texts:
When sending BTC (funds) from the Coinbase website, it asks for a bitcoin address to which to send it. What is one supposed to do, type it in?

What I would like to do is display a QR code in my Coinbase account that I scan using the wallet on my phone. My phone then sends a funds request to Coinbase which is displayed in my account. Then I simply send the funds.

I prefer using the Android Bitcoin Wallet instead of Coinbase wallet.

It seems like Coinbase at one time displayed a QR code for requesting funds from your account. I can't imagine how this might be implemented. Is it even possible?


texts: Has there been any cases of bitcoin being stolen without getting access to the owners private key?

texts:
With this question I want to exclude cases where someone is fooled to send BTC to a person (e.g. because social engineering or malware on their PC).

I have seen some arguments in comments to this Seeking Alpha article that claim that bitcoins cannot be stolen if their rightful owner is the only who has access to the private keys.

Has there been any cases of bitcoin being stolen without getting access to the private key?

For example: assuming that there is some exchange somewhere that allows a BTC buyer to manage their private keys outside of the exchange. Could it still be possible for e.g. a hacker to steal the BTC by manipulating the data at the exchange (outside of the blockchain).


texts: Understanding signing messages with bitcoinjs-lib

texts:
I'm trying to understand what a specific line of code does when signing a message using bitcoinjs-lib. Here's the code:

var bitcoin = require('bitcoinjs-lib')
var bitcoinMessage = require('bitcoinjs-message')

var keyPair = bitcoin.ECPair.makeRandom();
//private key
var privateKey = keyPair.toWIF();
// Address
var address = keyPair.getAddress();

console.log(privateKey);
console.log(address);

privateKey = keyPair.d.toBuffer(32)
var message = 'your message'
var messagePrefix = bitcoin.networks.bitcoin.messagePrefix

var signature = bitcoinMessage.sign(message, messagePrefix, privateKey, keyPair.compressed)
console.log(signature.toString('base64'))

The line I'm curious about is this one:

privateKey = keyPair.d.toBuffer(32)

What exactly is this code doing and why is it necessary?

Thanks,

Connor


texts: is there any way to get derivative path from public key and xpub?

texts:
I have an xpub derived from m/44'/0'/1' can I get that path again from generated xpub or pubkey?  something like
def get_path(xpub):

   return derivative_path


texts: What prevents someone from tainting the coin tumbling pool of the Wasabi wallet?

texts: Wasabi is a new type of wallet with a built in tumbler if I'm correct. What stops someone from tainting the tumbling pool of coins with non-approved coins? I'm weary of using these privacy tools as I don't want my coinbase account frozen just because someone mixed a bad coin in the lot.


texts: Wallets that trade all Cryptocurrencies?

texts: Been looking around, basically just learning...so much to learn lol. One thing I cant find but...is there a wallet/s that allows trading across all cryptocurrencies? They all seem to be quite restricted in one way or another??


texts: After mining a block and getting a hash. What do i do next?

texts: I am pretty new to bitcoin.Suppose I mined it with a mining software. Now what do i do to earn a reward? How do i see the transactions? How do know what the block is? Most importantly, where do i submit the hash? Please help me. I am very grateful.


texts:
I'm fairly proficient in C++ and wondered if the tenebrix client was safe to use?

Also if I wanted to review the code myself, are there any warning signs I should look for without studying the code in detail?

Thanks


texts: i am very frustrated, i managed to decrypt the backup file by doing the opensll command and as expected after putting the password i do see org.bitcoin.production which means i am at the right path but it also gives me 2 lines of some alien language which i dont know what to do with, i am not able to do the bitcoinj thing as all the opensll commands i see in the forums by schibald to get the wallet tool are saying invalid commands. so pls help me


texts: What is the easiest way to check what was the balance of address X at block Y? (without 3rd party services)

texts:
I need to have a possibility to check balance on every address. So far I tried used getreceivedbyaddress, but as far as I understand with this command I can check only addresses which I have in my wallet, right?

I also found information, that to have a possibility to analyze transactions of others I need to set txindex=1 in my bitcoin bitcoin.conf file. I read that this will help me with getrawtransaction which will be able to get me details about any transaction. Does txindex=1 will also help with getreceivedbyaddress?

and last, but not least... how to check balance of particular address in the past? Can I use getreceivedbyaddress <address> 100000 where 100000  would be amount of required confirmations, so I would check 100000 blocks in the past?


texts: Restricting transferability of Smart Contracts

texts: Can a smart contract be created which can be exchanged once at point of sale, and only transferred subsequently through a single approved exchange? Can that be written into the contract itself?


texts: What Bitcoin Mixing/Laundry Services are availble today?

texts:
A Bitcoin Laundry or Mixing Service is a service that accepts BTC payments, and returns the same BTC amount, only from coins that are unassociated to the original BTC. It is a privacy service that works well if it has massive usage.

What are some good mixing services? Is there any data on how well they actually anonymize (e.g. what size are their "stashes" or user base (bigger stash = bigger anonymity)?


texts:
Implementation of Blockchain in banks is said to be the new trend now. My question is: Would the private blockchain be kept private in a bank or will it be shared among a group of banks (or even possibly among all the banks)?

In the later case, is there no confidentiality issue, since a bank can know the transactions which are done by its competitors or its competitor's clients?


texts: What is deterministic validation for hardware wallets?

texts:
On bitcoin.com, they mention that the Ledger Nano hardware wallet "while not open-source, .. can be deterministically validated."

https://www.bitcoin.com/choose-your-wallet/ledgernano

What does this mean? What kind of validation can be performed? Does this have anything to do with the yellow "Centralized verification" label they have for it?


texts: Getting Bitcoins into my wallet from MtGox

texts: I have purchased bitcoins from MtGox and they appear in my account. However, I can't figure out how to get them into my wallet.


texts: What does Bitpay's {"error": "Invalid token"} mean?

texts:
I'm creating a web app that uses Bitpay for payments. I'm writing it in ruby (but that shouldn't matter), and have a class method bitpay_client with the body BitPay::Client.new('mYs3cretAPIkey').

Anytime I do BitcoinInvoice.bitpay_client.get("invoice/#{invoice_id}") I get the JSON {"error": "Invalid token"} back from the server. In Bitpay's documentation there's no mention of this message. I'm using the right api key, and I'm sure this is a real invoice. What does this message mean?


texts: Where can I find all options for the electrum config file?

texts:
I need to add oneserver and my server's IP to my electrum config on Mac. Also, I want to know which other options for the config there are.
I know that I can start with electrum --oneserver --server raspibolt.local:50002:s on Linux. How can I make this on a Mac - and with the config?
It seems to be that
"server": "bla.onion",
"port": "50002",

Are valid options, but what is with the :s?
EDIT: So,
"server": "bla.onion:50002:s",

worked! It did not work the first time, probably because I had set "auto_connect": "false".
I will still leave the question here.


texts: Which crypto currency exchanges are using segwit (bc1) addresses for its users?

texts: Are any of the cryptocurrency exchanges using native segwit (bc1) addresses for any of its users?


texts: Is there such a thing as a decentralized stock market desktop application, in concept similar to Bisq?

texts:
Please note that I've already visited thousands upon thousands of slick websites with fuzzy claims about being "the future of money" and I consider them all to be vaporware at best, and usually downright scams. I have no use for yet another such URL where all I get is the same nonsensical word salad but nothing that can actually be downloaded and used today, right now.
Is there such a thing as a currently launched, in-use, decentralized trading desktop application? That is, not a centralized website with "Register" and "Log in" on it, not "Open in App Store", not "Available for your Android phone", but an actual program that is downloaded, installed, run, and which then functions like Bisq, but instead, you can trade on stocks with zero KYC/AML BS, zero registration of any accounts, zero any BS except that you have to back up a file on your computer. Like I already do with Bitcoin Core and Bisq. But for trading stocks and perhaps other financial instruments, in a tokenized digital form which has nothing to do with the "traditional" stock market.
My guess/hunch is that this "is being worked on", but is not actually available yet.
Just like in Bisq, I would expect it to require me to initially send in some satoshis to my "wallet" inside of the application, which is then locked while used as some kind of internal tokens until I withdraw the BTC back to my own wallet. (If I have any left after making actual trades.)
As you might have guessed, I've extensively searched for this myself before asking here, and only found the kind of "word salad" fake websites which offer nothing but empty claims of being "the future".


texts: Sending from same address multiple times VS receiving to the same address multiple times

texts:
Is it completely safe to have multiple transactions sent to the same address?
I have read that "using" the same address multiple times could be unwise.
Does this refer to "sending from" or "receiving" or both?


texts: What hash rate should I expect using a BiFury with USB2.0 rather than USB3.0?

texts:
I'm considering the BiFury which is generates ~5GH/s on a USB3 port. They say,

  Miner is designed to be used with USB 3.0 port or USB 3.0 hub (must meet min. 0.9A per port to achieve full hashrate)
  USB 2.0 support is also available but hashrate will be lower.

However they don't quote an expected hash rate for USB2.0. Will it be significantly lower?


texts: How do I solve problem of my iMac now refusing to let me access Bitcoin Core?

texts: Immediately after a software upgrade to my iMac, an error message appeared: "Bitcoin Core quit unexpectedly" and I followed the instructions to "reopen" and the error kept repeating. How do I get back on bitcoin core?


texts:
Are sidechains intended to help Bitcoin scale? Do they reduce load on Bitcoin's main chain?

If not, why not?


texts: Is the alert system still in the main client's code? Will it be removed?

texts:
It is said that Satoshi removed the alert system from the client ... still, there are at least some leftovers in.

Is the alert system functioning in 0.3.24? Are there plans to remove all traces of it?

See also this answer.


texts: Which Two-factor authentication methods are available at which exchanges?

texts:
I see that Mt. Gox now supports the Google Authenticator app (on Android, iOS - iPhone, iPad, iPod Touch, and on Blackberry) for 2-factor authentication (in addition to support for Yubikey, of course).

What are all the various 2-factor (also referred to as multi-factor) methods available for Bitcoin-related sites (exchanges, eWallets, mining pools, other services, etc.)?


texts: Using a Bitcoin or Litecoin miner for attacking PBKDF2 / SHA-256

texts:
I'm wondering if it would be possible to utilize a Bitcoin or Litecoin miner to attack, say, a password database that uses PKBDF2 with HMAC / SHA-256. PBKDF2 uses multiple iterations of a PRF - usually HMAC-SHA1, but sometimes HMAC-SHA-256 - for protecting passwords. The idea is that these calculations have to be performed for each password, so that makes it more difficult for an attacker to test all passwords. The PBKDF2 method is defined in RFC 2898.

Sometimes statements are made that these functions are insecure because of attacks with ASICs and often total amount of Bitcoin SHA-256 hashes is shown as example of what can be done. Now I'm wondering if it would be possible to program a Bitcoin or Litecoin miner to find a password using brute force or a dictionary attack.

Assumptions:

HMAC SHA-256
the salt is known
output of PBKDF2 is 256 bit (the output of the hash) or less
"high" number of iterations, say 4K to 40K

To do this you would have to program HMAC using a single SHA-256. Furthermore, you probably would have to have a method to perform the iterations. The iterations use the same key (derived from the password) for HMAC but the data is dependent on the previous value. Obviously there also needs to be some way to generate or retrieve the candidate passwords.

Would it be possible to reprogram a miner to do this work, or are all the current miners too specialized to perform such operations? Is there a - possibly older - miner that can be reprogrammed to do this work?

Note that this question is about reprogramming/re-utilizing a hardware device. It is not a generic question of using the Bitcoin network to perform cryptographic tasks.

I've added Litecoin to the mix. Litecoin uses scrypt, which is already a Password Based Key Derivation Function in itself, which uses PBKDF2 as underlying PRF (hope that's OK, no answers yet).


texts: signing multiple input raw transaction - algorithm and sighash types

texts:
I have an unsigned raw transaction:
01000000020dcc23ccdb3665779a7657577cd33c5c0660e969ea2ffaf5438c58306ebc9dd20100000000ffffffff49508924c21b25ee2ff6aed61ccc202793aa992d3e033f12f2bf4a94d6346d010000000000ffffffff0240420f00000000001976a9140d7ca1e17524d6c96209cf503fb053613cecf8f688aca0f703000000000017a91452636ce984783dac880e139fa3b69b4d9be39ab68700000000

I have read these threads:
How to redeem a basic Tx?
Redeeming a raw transaction step by step example required
These threads explain signing a raw transaction with 1 input.
Questions
Do I understand correctly that both inputs are to be signed separately?
So first, we sign the first one, then the second one. To sign an input we replace scriptSig for this input with the scriptPubKey, that locks this input. ScriptSig for the other one remains blank.
It this correct?
But in both threads in step 13 something is appended at the end of transaction. It is called hash code type
What is this? Is this has anything to do with sighash type byte the one that is appended to the signature? If not how to determine this value?
What is the correct sighash type for the scenario I described above (signing inputs separately)?
Is this: 0x81 (SIGHASH_ALL | SIGHASH_ANYONECANPAY)?
Or should this be 0x01 (SIGHASH_ALL)?
I don't know which one is correct as transaction to be signed contains the other input (without scriptSig set but still, it contains it).


texts: Retrieving an addresses' public key from Pkscript/sigscript/witness

texts: Let's use this transaction as an example. In the transcation, address 3GGoy8NoCF62TCAPGidWMU3u1ZrgwmasFt has a pkscript, a sigscript and a witness. It is possible to use any one of these, or some combination of them to retrieve that address' public key?


texts: Is there a paper wallet generator for the new bech32 bc1xxx segwit address?

texts: Is there a paper wallet generator like bitaddress.org for the new bech32 bc1xxx segwit addresses?


texts: How to establish connection for mining testnet blocks on newly created altcoin

texts:
I was trying to clone an altcoin for educational purposes. I am total newby and I've got some plans to implement different PoW and continue working on cryto-currencies.

I followed the cloning guide by Shakezula.

I followed all steps in the guide, however I am losing the main point: thus I am unable to connect machines to start mining. Can anyone please explain what I am doing incorrectly? I am struggling with this and am really looking forward to understand.

What I do not understand is the point on port forwarding from Shakezula's guide:

  Side note: because I use a VPS for this, I don't really need to worry
  about port forwarding at that end. On the home PC, you will want to
  forward the port you chose for P2Pport in the cut and paste section to
  the PC you're using. For this example, that is port 55884.

What does it mean?  Does it mean that I should add this port in .conf file of the machines?

My case:

I am trying to connect compiled coins on two VM machines: VM1 with IP 192.168.122.121 & VM2 with IP 192.168.122.158 (they are able to ping each other)
In my conf files I only put rpc username/password
On VM1 I do ./barcoin -testnet -connect=192.168.122.158 &
On VM2 I do ./barcoin -testnet -connect=192.168.122.121 &

In .barcoin/testnet3/debug.log I get the following:

ThreadSocketHandler started connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
Flushed 0 addresses to peers.dat 42ms
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused}
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused

I added this port 55884 to conf file of one of the machines and getting the same error.

Then I added command connect=192.168.122.121:55884 to one of the conf files and started getting this:

trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121:55884 lastseen=0.0hrs connect() failed after select(): Connection refused
trying connection 192.168.122.121 lastseen=0.0hrs connect() failed after select(): Connection refused

Please help me with this one.
Thank you very much!


texts: Was the 51% attack a real threat in the early days of bitcoin existence?

texts:
The hypothesis of 51% attack is based on a malicious entity is able to control more than 50% hashrate of all mining nodes. It's understandable that there's huge amount of mining power existing nowadays, however, they grew up gradually since 2009.

I'm wondering when there were only a few of people who knew the bitcoin back to the 2009, therefore, surpassing 50% of mining nodes was fairly easy(for instance, assuming there were only 10 participants in the early days of bitcoin). Because controlling more than 50% of mining power probably just needed to control more than 10 computers in the earliest days since bitcoin birth.

As a result, do I need to worry about the 51% attack possibly happened in the blocks of which the height number is small and are those blocks trustable?


texts: Almost a month, transaction still not confirmed... help?

texts: I sent a transaction of 0.12 BTC with a fee of 11 sat/b. I expected the transaction to take a while to send, like a week, but it's already been almost a month. Is there something I can do to boost the transaction? A month ago I also sent a transaction of 0.03 BTC with a 15 sat/b fee and it took 4 hours to confirm. I didn't expected the 11 sat/b fee to take so much longer...


texts: finding new bitcoins vs processing transactions

texts:
I'm looking to understand how minting new bitcoins and processing transactions relate on the bitcoin network.

It seems that the term "miner" may refer to machines looking to mint new coins and machines processing transactions.

I can't find any information on whether submitting transactions is directly tied to minting coins.

I'm interested in processing pending transactions.  What does the process of finding unconfirmed transactions and submitting them into the blockchain look like?  Is confirming transactions just as expensive as minting new coins?

Does bitcoin core's bitcoind expose unconfirmed transactions?

How do unconfirmed transactions get submitted into the blockchain?

Thank you!


texts: Can mining with lots of laptops make money?

texts:
I have lots of laptops that are idle nearly all the time. Some of those laptops are new, some of them are old. Sometimes a word processor is opened and that's it.

Is it possible to use these laptops for mining in order to make money?


texts: How can Segwit increase transaction throughput if the same amount of data is stored in the blockchain?

texts:
I'm posting this after reading the answers to this: Where is the Signature stored in a SegWit transaction?

I've found out from reading that, that in Segwit, the "witnesses" (or signatures) that verify a transaction's authenticity are still stored on the blockchain. In which case, the same amount of bits ought to be used up by a given transaction as if Segwit weren't being used. If the block size remains the same, let's say 1MB, then it ought to hold the exact same number of transactions.

I've got an alternative possibility. Let's say that what actually gets sent to the nodes is a transaction with an empty signatures field (I think that such a field doesn't quite exist because of multi-sig stuff and scripts, but bear with me). Then the signatures can be sent through a separate channel. What actually gets stamped onto the blockchain is a transaction with an empty signatures field. And then because of the longest-blockchain-always-wins rule, the non-Segwit nodes will simply accept that the blockchain with the most number of transactions, which includes some funny signature-less transactions, is the authoritative blockchain.

But apparently reality is more complicated.

Also, there's a question about how much the longest-blockchain-always-wins rule can be abused. (The word "abused" does not imply a negative opinion). For instance, let's say I come up with FoobarWit. FoobarWit is the same as Bitcoin but with a larger blocksize (no Segwit). Once enough nodes adopt FoobarWit, then more such nodes will win the mining race, and so other nodes will effectively accept bigger blocks because the history is longer. I know that's not the case, but why?


texts: Does node order have meaning in a JSON describing the Lightning network graph?

texts:
LN clients can export their view of the network as a JSON file. For instance, in a file obtained from LND, a channel (edge) is described by this structure:

{
    "channel_id": "555479871492063233",
    "chan_point": "dbd46c11d740d7554454d2aad0520e18eedbc9c5e282d21dd065f275cbbe8380:1",
    "last_update": 1540396105,
    "node1_pub": "028e5a8e86540f703e1f58880d35d1e318a54c27d84ec1edbcde04a78ed4469a1e",
    "node2_pub": "02f6725f9c1c40333b67faea92fd211c183050f28df32cac3f9d69685fe9665432",
    "capacity": "300000",
    "node1_policy": {
        "time_lock_delta": 14,
        "min_htlc": "0",
        "fee_base_msat": "546000",
        "fee_rate_milli_msat": "10",
        "disabled": false
    },
    "node2_policy": {
        "time_lock_delta": 14,
        "min_htlc": "0",
        "fee_base_msat": "1000",
        "fee_rate_milli_msat": "10",
        "disabled": true
    }
}

Does node order have a meaning here? In other words, is node1_pub the one who initially opened the channel?


texts: I using CoinBase API for transactions in a game. I assign a callback URL with the address so as to get instant notification on payment transactions. the URL is called but it is not sending any data. Actually which parameter to get is not clear so used getParameterMap method, but it doesn't seem to work.


texts: How do I get number of pending transactions for an arbitrary blockchain

texts: How do I get number of pending transactions (queued and waiting for confirmation) for an arbitrary blockchain? Do I need to download that blockchain? There should be a more adequate way.


texts:
I have done quite a few upgrades in the past and this has never happened before:

$ uname -a
Linux back 3.16.0-4-amd64 #1 SMP Debian 3.16.36-1+deb8u1 (2016-09-03) x86_64 GNU/Linux

$ git checkout v0.13.1
$ git fetch --all
$ ./autogen.sh
...
$ ./configure LDFLAGS="-L/home/me/bitcoin/db4/lib/" CPPFLAGS="-I/home/me/bitcoin/db4/include/"
...
$ make clean  # I have had issues in the past, always solved with clean target
...
$ make
...
AR       leveldb/libmemenv.a
CXXLD    bitcoind
libbitcoin_util.a(libbitcoin_util_a-util.o): In function `GetNumCores()':
/home/me/bitcoin/src/util.cpp:796: undefined reference to `boost::thread::physical_concurrency()'
collect2: error: ld returned 1 exit status
Makefile:3336: recipe for target 'bitcoind' failed
make[2]: *** [bitcoind] Error 1
make[2]: Leaving directory '/home/me/bitcoin/src'
Makefile:8357: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/home/me/bitcoin/src'
Makefile:668: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1

Does anyone have any suggestion of anything I could try out to resolve this?

EDIT: I can't even rebuild v0.13.0, so I have most likely messed up my system in relation to boost. Looking into that

EDIT2 (RESOLVED): cleaning up the boost install resolves the problem (make check passes all tests). Any Bitcoin enthusiast who still doesn't quite know what he is doing (like myself) will easily attempt to install various Bitcoin libraries and utilities (e.g. libbitcoin bx for C++) with boost dependencies and end up with various bits and pieces of the library everywhere (both /usr and /usr/local hierarchy as well as boost distribution packages on top of existing stuff in /usr/lib/x86_64-linux-gnu/). So I removed the distribution packages, cleaned up /usr/include/boost and /usr/lib/libboost_* (and the equivalent on /usr/local), left the gnu folder alone (libreoffice will break otherwise), and installed a clean copy of boost (on /usr/local hierarchy). One thing to remember, if anyone tries to experiment by moving around library files, you need to run ldconfig to update the cache for the linker I think. Things started to make sense after I did that.

EDIT3: for the sake of completeness, if I decide to install boost in the /usr/ hierarchy rather than /usr/local/, then the above build will also fail for some reason. However, replacing the line:

$ ./configure LDFLAGS="-L/home/me/bitcoin/db4/lib/" \
              CPPFLAGS="-I/home/me/bitcoin/db4/include/"

by:

$ ./configure LDFLAGS="-L/home/me/bitcoin/db4/lib/ -L/usr/lib" \
              CPPFLAGS="-I/home/me/bitcoin/db4/include/ -I/usr/include"

leads to a succesful build.


texts: What are the arguments for and against using the Lightning Network with Bitcoin?

texts: In addition to the question in the title, when will Lightning Network go online, or, if there isn't a proposed date yet, what is a ballpark indication of when it might go online?


texts: Will I lose payments on a mining share in the time it takes to sync?

texts:
I bought a mining share a couple months ago from Bitcoop, downloaded the wallet that they suggested, and the wallet has taken this long to sync. The first mining payout was a few weeks ago.

Will I get that payment or is it lost?


texts:
If you click on random wallet at block explorer you get an instant info of all the transactions, balance etc etc. My question is, how their technology works exactly? Do they transform blk????.dat files in some kind of database and then read the stuff from database? If they are, what technology they use to put all transactions in database? Is there any protocol I try to do as well with programme?

When I open blk.dat files, I see only weird chars and from what I have read so far, the info there is not really transparent.


texts: USD Tether is running on the Bitcoin Blockchain right? Is it like a 2nd layer solution or how does that work?