texts: How Ripple actually transfer money from one bank to another?

texts:
Imagine there is bank A from USA and bank B from England, and they are both on Ripple Network.
Bank A wants to transfer $100 to bank B.

How does bank A put money in the Ripple network? Does it need to buy XRP from some gateway?

Suppose bank A already has the equivalent of $100 in XRP.
Bank B then receives XRP, but bank B is not interested in XRP, it wants pounds.

How will bank B convert to pounds? Does it need to find a gateway?
What if the exchange rate at this gateway is terrible for him?


texts: Can I defraud the merchant, or the merchant defraud me, on the bitcoin or lightning network?

texts:
Suppose I am buying a smartphone from an online merchant I don't trust. Neither do they trust me. Suppose we're trying to defraud each other.
There are two attempted fraud scenarios I can think of:

The merchant attempts to defraud me: I pay X satoshi to buy a smartphone, but I never receive it, and I'm afraid the merchant will never deliver it to me.
I attempt to defraud the merchant: I pay X satoshi, and the merchant eventually delivers it to me; I then attempt to refund the X satoshi payment after physically receiving the smartphone. (This is assuming we're both using the Lightning Network).

Can these fraud scenarios be prevented in the Bitcoin network? Alternatively, if I decide to make the payment off-chain (i.e. Lightning Network), then how does the Lightning Network prevent these scenarios?
More importantly, is it possible to prevent both scenarios simultaneously?
It is a form of distributed transaction to pay BTC while "simultaneously" receiving physical goods. At the moment, I think that this type of distributed transaction is not achievable with the Bitcoin network or Lightning network alone. Will we still need to rely on the judicial system to settle this or perform some sort of rollback?
I'm not well-versed with the Bitcoin or Lightning protocol, so if someone can correct or explain to me, that would be great.


texts:
I am developing JSP web. User will be redirected to another page only if he sends the certain amount of BTC, is there any listener which could check if money arrived to my wallet from the certain wallet address?
And after leaving the page is there possibility to automatically send the money back to the user?

Maybe some good tutorial on bitcoinj or something? Any suggestions?


texts: Cpuminer problem: empty reply from server

texts:
When I run the following command:

minerd.exe -o http://eu-stratum.btcguild.com:3333 -u username_1 -p password -a sha256d -R 2

I get this:

2 miner threads started, using 'sha256d' algorithm.
Binding thread 0 to cpu 0
Binding thread 1 to cpu 1
HTTP request failed: Empty reply from server
json_rpc_call failed, retry after 2 seconds

How can I solve this problem?


texts:
Every time I restart my bitcoind, all the wallets will need to be reloaded:

$ bitcoin-cli listwallets
[
  ""
]
$ bitcoin-cli loadwallet test01
$ bitcoin-cli listwallets
[
  "",
  "test01"
]

So I was wondering that is there any ways to auto load all the wallet under path /home/ubuntu/.bitcoin/testnet3/wallets when startup? I have tried adding some config in bitcoin.config, but all didn't work for me:

wallet=/home/ubuntu/.bitcoin/testnet3/wallets
wallet=/home/ubuntu/.bitcoin/testnet3/wallets/test01
wallet=1

bitcoin core version: v0.18.1


texts:
How can one calculate betweeness centrality of your node as mentioned in this video. I would like to take into consideration

base_fee_msat
fee_rate

Is there a smart way to figure out what suites your lnd node?


texts: how to insert new checkpoints in a bitcoin clone


texts: How does an SPV client forms a transaction which is then Broadcasted?

texts:
As per my understanding, an SPV client only keeps a track of the block headers in its own database. So when a user tries to send bitcoins using that particular SPV client, how is the transaction constructed?

A user using that client will probably enter the amount he wants to send and the destination address. And he probably will be signed in using his private key.

So using these 3 data i.e. amount, destination and privateKey how will the SPV construct the whole transaction object.

Because I know that if I have to manually write a transaction by hand, I need:

Previous Transaction Hash (Funding Transaction).
Sequence Number of the UTXO I am trying to spend.
ScriptSig or the unlocking key, which is constructed using the privateKey and the hash of the entire transaction body.
Output Value.
ScriptPubKey which is constructed using the destination address.
SigHash Code.

So I am just supplying amount, destination and private key. How will the SPV client get the remaining values such as Prevout hash, sequence Number, how many UTXOs to be unlocked and how many new UTXOs should be formed?

It will be very helpful, if someone mentions a codebase where the implementation is given.


texts: How could block propagation time be reduced?

texts:
This website measures block and transaction time propagation.. At the time of writing, the time required for 90% of surveyed clients to get a block is about twelve seconds. (I just averaged the last five days.)

How could this be reduced? On a related note, what are the major causes of propagation delay? Is this primarily caused by network latency, network bandwidth, or by clients verifying the block?

Related:

How long does it take for blocks to propagate?
"Information and Propagation in the Bitcoin network", by Decker and Wattenhofer.


texts:
Scenario

Say you have configured a ledger wallet with 10 BTC and 10 ETH. You then lose this said wallet but you have the 24 unique words. You buy another ledger wallet enter the 24 words and BAM, your wallet is back.

Question
My question is where did the backup come from ? And how is it encrypted.

Thanks!


texts:
I read in this great thread that which BIP are standards is not always obvious.
What about BIP 65? To which extent is it standard?

Currently, all I know is that "Miners following the developers of the "Core" Bitcoin client have been adopting BIP-65, with approximately 25% of the last found blocks claiming to be ready for the soft fork on the version string in the block header. " ... not very precise.

Thanks


texts:
P2Pool is an open source peer to peer mining pool. It currently charges a fee of 0.5%.

Is it possible to just fork P2Pool protocol and eliminate the fee? Has this been done? If so, how can P2Pool still retain users when a cheaper alternative remains? If this hasn't been done yet, why not?


texts: how to enable wallet in a confirmed node

texts:
I installed/compiled my Bitcoin Core RPC client version v0.16.2.0 and i used --disable-wallet flag.

I think this is the reason I am seeing "Method not found" errors when trying to GetNewAddress

how can i install/enable it after having fully confirmed node with up to date blockchain?

os: Ubuntu 16.04.5

solution

accepted the answer below but in my case since i set it up sing apt-install bitcoind the wallet feature was already there, i just needed to flip the disablewallet=1 flag in my bitcoin.config


texts: Is there a command line Bitcoin CPU miner for Windows?

texts: Is there a Bitcoin miner that I can run using the command line on Windows? I want a CPU miner, not a GPU miner.


texts: How do blocks signal whether it supports segwit for the 95% threshold?

texts: Ideally, I'd also like to see graphs that indicate how close we are to segwit adoption and the number of minimum blocks we are away from actual segwit adoption.


texts: Bitcoin daemon Error: Invalid combination of -regtest and -testnet

texts:
How to solve above title problem?

I first started with bitcoin as regtest.

Now I want to launch bitcoin as -testnet.

So I did like

root@q352-3023-vps:~/.bitcoin# bitcoind -testnet -daemon

but above error..


texts: What are the differences from the 2 main mimblewimble implementations, BEAM vs GRIN?

texts: Beam is being released tomorrow, but Grin has not yet. What are the main differences from these 2 mimblewimble implementations?


texts: We know that the bitcoin for mining a block is going to converge to approximately zero as the number of bitcoins will be almost constant after a certain amount of time. So, mining will no more profitable in the future and if no one is going to maintain the ledgers then how the bitcoin going to survive?


texts:
Given a bitcoin block, what's the easiest way to determine the minimum net fee rate (including ancestors) for transactions in that block?
A naive approach would be to just find the minimum fee rate for a single transaction, but that does not take ancestor and descendant chains into account. I want to know the minimum clearing fee rate for the block considering the full ancestor/descendant chains
I've been looking through the transaction selection algorithm to try and understand the logic, and figured I could try and reverse engineer it to decode an existing block... but I'm wondering if someone has already done the work and created a good tool/script/api that can parse an existing block and determine the minimum net fee rate of the block's transactions


texts: Unconfirmed Transactions on Balance and History

texts:
Is there any way to see the unconfirmed transactions within the balance of the CoPay's Bitcoin Wallet and get notifications when it receives an unconfirmed transaction?
Because I didn't see my transaction and had to search it in the blockchain to be sure that it exists .. and I remember that some other wallets already do this with an UNCONFIRMED tag.


texts: What is the meaning of in-script and out-script in standard bitcoin transaction?

texts:
I am new to bitcoin world and I am reading this paper: Secure multiparty computations on Bitcoin
https://eprint.iacr.org/2013/784.pdf

The author said on page 7 that the standard bitcoin transaction can be represented as in attached picture. Could anyone explain what is meant by in-script and out-script. And Could any one give a easy explaniation to that standard transaction?


texts:
I am forking the Altcointipbot for reddit to make a tipbot for Litecoin. There has been a lot of problems that I've managed to solve, but this one I cannot seem to solve. When I try to start the script, it stops when trying to make a RPC request, giving me an error with code 500. This is the traceback:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "cointipbot.py", line 539, in __init__
    self.self_checks()
  File "cointipbot.py", line 144, in self_checks
    b.register()
  File "ctb/ctb_user.py", line 230, in register
    new_addrs[c] = self.ctb.coins[c].getnewaddr(_user=self.name.lower())
  File "ctb/ctb_coin.py", line 172, in getnewaddr
    self.conn.walletpassphrase(self.conf.walletpassphrase, 1)
  File "ctb/pifkoin/bitcoind.py", line 69, in __call__
    return server._rpc_call(self.method, *args)
  File "ctb/pifkoin/bitcoind.py", line 216, in _rpc_call
    raise BitcoindException('%d (%s) response from bitcoind' % (response.status, response.reason))
ctb.pifkoin.bitcoind.BitcoindException: 500 (Internal Server Error) response from bitcoind

My guess would be that the RPC request goes to bitcoind (litecoind), where as now you need to use bitcoin-cli for requests (at least that's how it is in the terminal). However, I cannot seem to find anything in the code that's specifying that the request goes to bitcoind and not bitcoin-cli, so maybe it takes care of that automatically? I am by no means very good at this, so I was hoping someone with more experience could help me figure it out.

The part in the code where all the RPC requests happens can be found here: https://github.com/dpifke/pifkoin/blob/master/python/bitcoind.py

The rest of the source is here, but it's probably not necessary: https://github.com/vindimy/altcointip

I've already edited the litecoin.conf to include rpcport, rpcuser, rpcpassword and server=1.

Thanks in advanced!


texts: Impact on Bitcoin value due to lost bitcoin wallets

texts:
My question is 2 part:
1. How does somebody know that a set of bitcoins is lost? Merely declaring that I've lost my private key and hence bitcoin makes the coins lost?
2. What impact(and why?) would be on the price of bitcoin if I lose a huge amount of bitcoin today? Say 1 billion?


texts: It would be great if it would be possible to spend Bitcoins via Flattr. Does anybody know if there is something planed?


texts:
Possible Duplicate:
  How could the bitcoin protocol be changed? Has this ever occurred?

Given Bitcoin is a system based on consensus, is it possible and under what situations would the Bitcoin community consider changing some of it's underlying 'hard-coded' laws. Things such as the number of Bitcoins in circulation the rate of Bitcoin production or the number of confirmations before a transaction is confirmed?


texts: Rolled out my own no-fiat service. What will the tax man need?

texts:
Background:

I have programmed my own service using https://bitcore.io and I have a limited company set up in the Uk! My company's original intention was to deal with Paypal transactions. (but we are now going to only use Bitcoin!)

We plan to only accept BTC ,only pay and make trades in BTC (never converting money within the company to pounds or any other fiat currency).

  Additionally I am recording every transaction and payment in my database - for the record and in case the tax man would need to take a look at what is going on.

To put it very simply; my company has two instances of dealing with Bitcoin:

A user buys my product with Bitcoin and I collect it in my own private key
A user requests a payment from me. I pay them in bitcoin to a public address of their choice using another private key of mine

My question is:

If my company is never dealing with any fiat money; what information should I be sending to the tax man?

It is a registered company after all (dealing with international clients) and I want to comply with the law.

What are my tax obligations?

From https://www.gov.uk/government/publications/revenue-and-customs-brief-9-2014-bitcoin-and-other-cryptocurrencies/revenue-and-customs-brief-9-2014-bitcoin-and-other-cryptocurrencies

when Bitcoin is exchanged for Sterling or for foreign currencies,
such as Euros or Dollars, no VAT will be due on the value of the
Bitcoins themselves
charges (in whatever form) made over and above
the value of the Bitcoin for arranging or carrying out any
transactions in Bitcoin will be exempt from VAT under Article
135(1)(d) as outlined at 2 above

However, in all instances, VAT will
   be due in the normal way from suppliers of any goods or services sold
   in exchange for Bitcoin or other similar cryptocurrency. The value of
   the supply of goods or services on which VAT is due will be the
   sterling value of the cryptocurrency at the point the transaction
   takes place

So I am to say nothing?? O.o


texts: how to view raw json bitcoin transactions

texts: Is there any place i can view raw json bitcoin transactions (like discussed in this tutorial).


texts: I want to update my Copay wallet but not sure if I'm supposed to install the new (updated) version of the wallet or what? Will it not mess with the old version or do I have to remove it first? Or do I transfer my btc afterwards?


texts:
So I recently made a very small test order of Digix DAO in the Ethereum market (Using bittrex), and I noticed that it showed up in the Market History section.

It looked a little like this (NOT EXACT)

BUY - RATE 0.0... - TOTAL 0.0... ......

So I bought X DGD with Y Ethereum.

However, there was no SELL order to compliment my BUY order.

When I bought the Digix DAO, I bought it from a seller, who sold it to me. Why isn't his SELL order in the market history, but my BUY order is?

This also applies for the opposite: What does it mean when there is a SELL order with no BUY order to compliment it?


texts: Why is it so expensive to transfer Bitcoins?

texts: I am starting with bitcoins and I want to buy some neo and ripple. Like every newbie I typed "Buy neo" on google, and a lot of tutorials say I can not buy directly neo, I have first to buy some bitcoins (for example in coinbase.com) and then transfer them to a cryptocurrency market like binance.com and then in binance I will be able to change my bitcoins in neo and ripple. That's what I done and I it worked perfectly, but I was very surprised by the cost of the transfer from coinbase to binance, when transfering 120 dollars around 30 dollars where taken for transfer fees !?! What's the point in using alternative moneys if it is far more expensive than actual banks? And how can I do to avoid these transfer fees next time I want to buy neos??


texts:
I am interested in the difficulty right now. That is, the miners are working a block right now and they have a target. Both of the RPC commands "getmininginfo" (or "getdifficulty") and "getblocktemplate" can be used to get a number that represents a "difficulty".

"getmininginfo" (or "getdifficulty") gives a difficulty value directly. "getblocktemplate" gives the "target" and the "bits", both of which can be used to derive a difficulty value. I understand that miners work according to a "target." But, which target?

I list two possibilities below. Which (if either) is the correct case?

1) "getmininginfo" gives the difficulty right now, and "getblocktemplate" gives the difficulty for the next block under the assumption that this block will be solved within the next second.

2) "getblocktemplate" gives the difficulty right now (through the "bits" or "target"), and "getmininginfo" gives what the difficulty was for the most recently solved block.

If both of these are wrong, what exactly do the difficulties given by the two commands really represent?


texts: How many types of mining pool are exist for bitcoin or litecoin?

texts:
I would like to know exactly how is the type of different Bitcoin or litecoin pool ?!

For example when you have P2POOL , it can be getwork or stratum but they are protocol ?!

In some pool like BTCGuild when you mine, the reward will be added instantly but in P2POOL takes time to see the reward in you wallet.


texts: What hash algorithm is used in Bitcoin Cash?

texts: I know that bitcoin uses hashcash as PoW algorithm, Ethereum uses EtHash and Litecoin uses Scrypt. But I didn't found anywhere the PoW algorithm used in BitCoin Cash, does it uses hashcash too?


texts: Unable to get transaction with json-rpc command

texts:
I am trying this command to get transaction from bitvoin testnet:

curl  --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "gettransaction", "params": ["txId"] }' -H 'content-type: text/plain;' http://username:password@IP:PORT/

And i am getting following error

{ "result":null, "error":{"code" :-32601, "message" : "Method not found"}, id:curltext}

Please help.


texts: Where is the exact code part of the walletnotify function?

texts:
I'm new on the BTC project, so please spare me if I asked something newbies.

I downloaded the latest 0.92 BTC source code and trying to make a customize to the walletnotify function for myself while running the bitcoind. But when I search into the code, that triggered runCommand() at util.cpp and pew "End of the road".

I googled about this walletnotify function, but all I seemed are only the usage infos. So I think it's time to ask the question here but thinking the dead-end by myself.


texts: Can someone explain this [outdated] BIP12 OP_EVAL exploit?

texts:
I understand that BIP12 was withdrawn, and probably because of this exploit below.  Can someone explain how this attack would have worked and the effect it would have on the network?

 for (;;) {
    RAND_bytes(nonce.b, sizeof(nonce));
    RIPEMD160(nonce.b, sizeof(nonce), digest);
    if (
      digest[0] == 174 && // OP_CHECKMULTISIG
      digest[1] ==  76 && // OP_PUSHDATA1
      digest[2] ==  16    // 0x16
    ) {
      // We'll print status info on partial hits, just to make things more
      // interesting.
      printf("%llx\n", nonce.i);
      print_hex(digest, 20);

      // Check for full hit
      if (digest[19] == 117) // OP_DROP
        return;
    }


texts: if bitcoin plunges to $0 will altcoins be affected?

texts:
If the value of bitcoin where to drop significantly to amost no value would altcoins be affected ?

i guess they would because usually we convert to BTC before cashing out into fiat but wanted other opinion.


texts:
im testing the binance api but cant get over the signature problem can u spot a mistake on my signature?:

   const crypted = CryptoJs.HmacSHA256("timestamp=" + new Date().getTime().toString() + "&recvWindow=5000" , this.APISECRET).toString();


texts: Genenerate address offline, but blockchain knows about my address

texts:
I generate new address in client. I hear that blockchain doesn't know about it. Blockchain will know about it when I use this address for transaction.

My example:
I generate this address(offline): 1J1JqUPqKq4XvrDRioMSMYKrwL3wKdJ1Fe
I haven't used yet. How does website blockchain.info know about my address??? https://blockchain.info/address/1J1JqUPqKq4XvrDRioMSMYKrwL3wKdJ1Fe


texts: Is it 'safe' to store hashed values of my mnemonic seed phrase on my computer?

texts:
I am setting up my hardware wallet, and have written down my mnemonic seed phrase physically, but also want a way of accessing it from my computer.

If I add all the seed words together, and hash it by a specific combination of the existing words, would it be safe to store on a computer?


texts: Is there an efficient way to exploit arbitrages between the different exchanges?

texts: The Bitcoin ratio vs other currencies is not the same among exchanges. Is there currently a way to exploit this arbitrage and profit?


texts: Is change of Bitcoin address of an account possible?

texts:
I have multiple Bitcoin addresses in my Bitcoin Daemon,

Which address will be used for receive transaction
Can i change my default account address(mentioned in 1) to new one


texts: Why is a "first seen" rule is used to pick a side in a honest split, instead of deterministic criteria?

texts:
I was just thinking, why nodes pick the first block they see when there is an honest split, instead of picking, for example, the one with the "best hash" (number further away from the difficulty cut)?

Deterministic criteria like that would allow the entire network to quickly know which block wins, and everybody would then build on top of that block. Much less hashpower would be wasted on the dead branch.

Unless there's some risk/problem in it I'm not seeing...


texts: I would like to dig into the open Taproot PR to understand it, test it and possibly even review it. Any advice or recommendations?

texts: I would like to dig into the open Taproot PR (PR #19953) to understand it, test it and possibly even review it. Any advice or recommendations?


texts: Both Bitcoin and Litecoin have an intensity setting when mining.  What does this mean?


texts: my btc were stolen with an anonymous transaction. How was possible? Electrum should be a offline secure wallet, besides they were stolen during the night , with my desktop offline. The receiver address is visible. Can i retreive my btc? Moreover, in the future how can i trust every offline wallet? I donwloaded the electgrum sofware from the official site.


texts: I downloaded many [X] core software, including Bitcoin, Litecoin and others, and they all worked fine, except for Dogecoin Core. It keeps saying "No wallet has been loaded". There was a wallet.dat file there, but I got the same error when it was there (it's an empty wallet, btw). Now I moved that file somewhere else, and Dogecoin core is not creating a new wallet, and keeps giving the same error. How can I fix this? Please advise.


texts: Can I pay someone else to operate a miner on my behalf?

texts: Is there a company or individual out there that sells Bitcoin miners and holds them under their supervision for a fee? If so... I'd like to know.


texts: bitcoin-cli JSON-serialized error output

texts:
Is there a way to make bitcoin-cli output JSON-serialized errors? For example if I do

bitcoin-cli getblock foo

the output is

error code: -5
error message:
Block not found

I want the output to be something more like:

{
  "error": {
    "code": -5,
    "message": "Block not found"
  }
}

Behind the scenes, that's what the RPC response body looks like, and I want to tell bitcoin-cli, "Don't pretty-print the error if there is one. Just give me the JSON response."


texts: Bitcoind daemon: error connecting to the server?

texts:
I am trying to create a new bitcoin address and store it in a shell variable $NEW_ADDRESS.

When I run this command:

$NEW_ADDRESS=$(./bitcoin-cli getnewaddress)

I get the following errors:

error: Could not connect to the server 127.0.0.1:8332
Make sure the bitcoind server is running and that you are connecting to the correct RPC port.
-bash: =: command not found

I have tried everything to fix the connection error, including typing the command:

./bitcoind -rpcport=8332

Or even, changing the bitcoin config:

nano ~/.bitcoin/bitcoin.conf

And typing these lines on the configuration:

rpcconnect=127.0.0.1
rpcport=8332;

But nothing works. Does anyone have an idea on how to troubleshoot and fix this?

Thanks in advance.


texts: Which part of the code is responsible for validating blocks? I'm working on a BIP to modify the structure of block.h, and I think that would definitely affect the validation process. Can anyone point me in the right direction for the files I would need to change to update the validation process?


texts: Lightning Network `channel_update` message Flag clarification

texts:
This is a lnd.log line:

2019-01-11 12:20:13.904 [DBG] PEER: Sending ChannelUpdate(chain_hash=000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f, short_chan_id=601495532567724033, flag=256, update_time=2019-01-11 12:19:08 +0100 CET) to 46.229.165.136:9735

Since I cannot find a direct correlation with the spec at https://github.com/lightningnetwork/lightning-rfc/blob/master/07-routing-gossip.md
can someone clarify the "flag" value?

Where can I find the information below?

[1:message_flags]
[1:channel_flags]
[2:cltv_expiry_delta]
[8:htlc_minimum_msat]
[4:fee_base_msat]
[4:fee_proportional_millionths]
[8:htlc_maximum_msat] (option_channel_htlc_max)

Are they encoded in some way in this "flag"? How?


texts: I like how Bitcoin Core uses Gitian to make their builds deterministic. But Gitian is also a really complicated workaround. Is there any research being done into alternatives for deterministic builds?


texts: What order do transactions appear in a block? Is it up to the miner?

texts:
It seems to be random or up to the miner from what I can tell.

But to store blocks, one must keep the order of the transactions (in some position column, etc) because regenerating the block for later retrieval requires putting the transactions back in the same order.  Is this correct?


texts: BTC confirmed however funds not received

texts:
I would really appreciate if someone could help me with my problem. I recently sold some coins to an exchange and then wish to have few bitcoins i.e. 0.01627139, transferred to my wallet which never happened. Transaction Id given to me by exchange is -  13e049ecf32a3226f7c82b558d968c255971272024a37b3509bb90effa92f8f2.

when I search with above-mentioned transaction id in blockchain.info I see around 120 confirmations to the block however I have not received my amount i.e. 0.01627139 in my wallet and it says as "Unspent". I wish to know is it the fault of the exchange or my wallet provider not reflecting this transaction ? If it is the fault of exchange do i need to ask them to rebroadcast my transaction again.
What is the "Unspent".


texts: Besides mining Bitcoin what is another good use for an Antminer S1?

texts: Are there any other SHA-256 coins out there that are worth mining? Also, would I be able to mine scrypt-based coins?


texts: Why are some transactions unavailable in my debug window?

texts:
I got a block and asked for the data in its first transaction and that generated an error.  The following is from the console tab in the Debug window:

10:52:52 getblock 000000000030bfd22ed67169b6bbf9ba994618fa9840642d395b56134f15176c

10:52:52
{
  "hash": "000000000030bfd22ed67169b6bbf9ba994618fa9840642d395b56134f15176c",
  "confirmations": 332460,
  "size": 216,
  "height": 81626,
  "version": 1,
  "merkleroot": "1ebda57ace225010d23d72619dbda5ee250dc4536f7c3428a9a419f06438ca54",
  "tx": [
    "1ebda57ace225010d23d72619dbda5ee250dc4536f7c3428a9a419f06438ca54"
  ],
  "time": 1285297753,
  "mediantime": 1285295165,
  "nonce": 71992579,
  "bits": "1b4766ed",
  "difficulty": 917.8307413015116,
  "chainwork": "00000000000000000000000000000000000000000000000000650ba70ddba016",
  "previousblockhash": "00000000001272fc0e0cfa9d08d854cfac681a939dccc21aecd9f7074fb0df2b",
  "nextblockhash": "00000000001bd5ac7329097b9888628c33c7adeecfc6e46f74fbab006f4c2127"
}

10:53:42 getrawtransaction 1ebda57ace225010d23d72619dbda5ee250dc4536f7c3428a9a419f06438ca54

10:53:42 No information available about transaction (code -5)

This happens in Bitcoin Classic and in Bitcoin Core.  I don't have a bitcoin.conf file in the folder where bitcoin-qt.exe lives, but I do have one where the chainstate and blocks folders are located.  It has five lines in it and each one starts with "addnode".


texts: What incentive is there for a miner to not cancel his own 'real' txs

texts:
It is said that a Bitcoin miner attacker with enough CPU power to outrun the entire network is better off mining honest bitcoins - which is not correct since by creating a false block chain the attacker already wins the coinbase on the way, just like he would if he behave honestly.

Actually, an honest miner has all the incentive to defraud by adding to his block transactions that cancel his own 'real' transactions.

Or am I missing something?

EDIT- and maybe an answer

Let me give an example, lets say Alice owns a very big pool (big pools had known to create up to 6 blocks in a row), also Alice buys something from Bob for 1 bitcoins every 10 minutes.

Alice could try to do double spending of each of her payments (by passing the same bitcoins to herself) and use the second transactions in the block she is mining.

Note that this is all completely legit.

If the pool solves the proof-of-work, then her 'real' txs will be canceled - Bob can wait 10 minutes to see if the transaction gets confirmed or not, but it might not be enough in the case that there was a fork.

Conclusion:

A owner of a big pool can try to create doublespends but he will win his btc back only in rare occasions when:

there was a fork
Bob didn't check the fork, and didn't wait enough time (e.g. 1 hour) to see if the transaction was confirmed
The good that Alice bought is not associated with any physical address (so that Bob cannot find Alice and claim for his money).


texts: Why does bitcoin uses INIT_PROTO_VERSION (209) for addrme and addryou in the Version Message

texts:
Why does Bitcoin use INIT_PROTO_VERSION (209) in the addrme and addryou message of the Version Message? Why is it not using the nodes protocolVersion which had been advertised in the same Message.
This is part why the nTime from the node in the Version Message will be ignored
Code used for Debug in protocol.h
   SERIALIZE_METHODS(CAddress, obj)
    {
        SER_READ(obj, obj.nTime = TIME_INIT);
        int nVersion = s.GetVersion();
        if (s.GetType() & SER_DISK) {
            printf("nVersion %d\n", nVersion);
            READWRITE(nVersion);
        } else {
            printf("Not evaluated nVersion %d Type %d\n", nVersion, s.GetType());
        }
        if ((s.GetType() & SER_DISK) ||
            (nVersion >= CADDR_TIME_VERSION && !(s.GetType() & SER_GETHASH))) {
            READWRITE(obj.nTime);
            printf("nTime %d\n", obj.nTime);
        } else {
            printf("Not evaluated nTime %d\n", obj.nTime);
        }
        READWRITE(Using<CustomUintFormatter<8>>(obj.nServices));
        printf("nServicesInt %d\n", obj.nServices);
        READWRITEAS(CService, obj);
    }

See below the Output
BTC's
Receive addrMe
Not evaluated nVersion 209 Type 1
Not evaluated nTime 100000000
nServicesInt 0
Receive addrFrom
Not evaluated nVersion 209 Type 1
Not evaluated nTime 100000000
nServicesInt 1033
2020-07-07T01:35:08Z New outbound peer connected: version: 70015, blocks=638069, peer=1 (full-relay)

Is this a wanted behavior?


texts: segwit compatilibity bc1 and 3 bitcoin wallet?

texts:
I would like to know what's the better aproach for upgrading from a legacy address to a segwit one, but there are two type of segwit as P2SH starting with 3  and Native SegWit (bech32) starting with bc1, but don't know which of the two segwit one, is better and is compatible to transfer and receive from a legacy one. ?

I know that a segwit wallet helps to reduce the size of the tx, and reduce fee,but don't know if there is a drawback for each type of segwit?


texts:
I implement a webshop, basically it is more than a wehshop a marketplace and I would offer Bitcoin payment. There are 3 roles: buyer, seller, and the marketplace.
The procedure I imagined, that that seller has the private key. Seller derive adresses, where one would epxect the incomes. Seller hands those addresses to marketplace.
When buyer comes and want to purchase a product, marketplace return an address. Marketplace record in DB which buyer and address belongs together. Later Maketplace pull Blockchain, and check wether amount appeared in the specified address. If so, than pruduct can be shipped.
So:
Is it possible derive pathes without prive key? If so in which wallet?


texts: I used edge wallet to send my bitcoin from my wallet to my cash app but i used a low fee soo its been unconfirmed for 10 days what can i do?

texts:
My transaction 5c8552a6744b3428d3ec4b5c0dd8b378ffeb4efd703b76a2b9d106250234d766
Has been unconfirmed for 10 days is there anything I can do to get it confirmed or do I just have to wait?


texts: IBD problem: Reindexing blocks and syncing starts over every time I shut and open Core

texts:
I am currently doing IBD in segments due to logistical reasons, but each time I safely shut down Core and unplug my hard drive (HDD, 1TB) and then plug it back in and start up Core, it starts in 2009 and reindexes all blocks on disk. I've finished all indexing in one go, and still had to redo it for some reason.

I'm using v 0.19.01 on a Windows 10 computer.


texts: Sharing BIP32 extended master public key

texts:
I have User A who generates BIP32 Master Public and Private Keys. They share the Master Public Key with User B.

Using the Master Public Key User B generates Address of A and sends bitcoins from Address of B to Address of A.

Will the transaction be received in wallet of User A, if User A knows the index used by User B?

The main idea is that User A don't want to share its receiving address with User B. Instead of that User A must find out itself from the Master Public Key.


texts: Python code to generate private ECDSA key

texts:
Would this Python code generate a valid ECDSA private key?

import random

def r(a, b):
    sys_ran = random.SystemRandom()
    return sys_ran.randint(a, b)

def create_private_key():
    hex_chars = '0123456789ABCDEF'
    ran_hex = '';

    for i in range(64):
        ran_hex += hex_chars[r(0, 15)]

    max_hex = 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141'

    if int(ran_hex, 16) <= int(max_hex, 16):
        return ran_hex
    else:
        return create_private_key()

private_key = create_private_key()
print('Private key: ' + private_key)

As far as I can tell from the Bitcoin wiki, an ECDSA private key is any 64 character hexadecimal (or the corresponding decimal) number between 0x1 and 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141. It doesn't mention anything about any special algorithms required for the private key to be valid.


texts: Calculate transaction fee for external addresses which doesn't belong to my local bitcoin-core server?

texts:
I am doing transaction on addresses which are created outside of my local bitcoin-core server using third party lib. I am having its private/public key. I am
 able to create raw transaction using "createrawtransaction" and also able to sign and send txn using "signrawtransactionwithkey" & "sendrawtransaction" but when i am trying to calculate txn fee and adding change address using "fundrawtransaction" or  "walletcreatefundedpsbt", am getting error as "insufficient fund" but i have enough unspent btc on my addresses. So how we can calculate txn fee before signing and sending txn for external addresses?


texts: What is the P2P technology/protocol used by Bitcoin to find nodes and distribute messages across them?

texts: I am wondering if there is a standard/de facto P2P library/implementation/spec used by Bitcoin Core and other implementations of Bitcoin?


texts: How can I withdraw my bitcoins from my blockchain wallet and convert them into cash?

texts: I tried to withdraw from my blockchain wallet from blockchain, but I don't understand how to convert to cash and withdraw to the financial establishment available in my country.


texts: Using importmulti with internal set to true does not add any change keys. What am I doing wrong?

texts:
First I call:

curl --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "createwallet", "params":["ColdWallet", true] }' -H 'content-type: text/plain;' http://user:password@127.0.0.1:18332/

Which returns:

result = {
    name = ColdWallet;
    warning = "";
}

I then import keys to the keypool:

bitcoin-cli getdescriptorinfo "wpkh(tpubDFLL8VNUhpLNVLw8179WCEuMZtKtTDd7EeYeFDtThzisj6wfJ4Zi43qUvCE7ciCFxVKZYssRr9P9PerLefkVEjKL6CphUvbGv1CrSCS2KUB/*)"

responseString = {

  "descriptor": "wpkh(tpubDFLL8VNUhpLNVLw8179WCEuMZtKtTDd7EeYeFDtThzisj6wfJ4Zi43qUvCE7ciCFxVKZYssRr9P9PerLefkVEjKL6CphUvbGv1CrSCS2KUB/*)#udrnh6f5",
  "isrange": true,
  "issolvable": true,
  "hasprivatekeys": false

}

bitcoin-cli -rpcwallet=ColdWallet importmulti '[{ "desc": "wpkh(tpubDFLL8VNUhpLNVLw8179WCEuMZtKtTDd7EeYeFDtThzisj6wfJ4Zi43qUvCE7ciCFxVKZYssRr9P9PerLefkVEjKL6CphUvbGv1CrSCS2KUB/*)#udrnh6f5", "timestamp": "now", "range": [0, 99], "watchonly": true, "label": "Fully Noded Cold Storage", "keypool": true, "internal": false, "rescan": false }]'

result = (
        {
        success = 1;
    }
)

I then set keypool to false and internal to true:

bitcoin-cli -rpcwallet=ColdWallet importmulti '[{ "desc": "wpkh(tpubDFLL8VNUhpLNVLw8179WCEuMZtKtTDd7EeYeFDtThzisj6wfJ4Zi43qUvCE7ciCFxVKZYssRr9P9PerLefkVEjKL6CphUvbGv1CrSCS2KUB/*)#udrnh6f5", "timestamp": "now", "range": [100, 199], "watchonly": true, "keypool": false, "internal": true, "rescan": false }]'

result = (
        {
        success = 1;
    }
)

I can use getnewaddress -rpcwallet=ColdWallet without issue but if I try:

curl --data-binary '{"jsonrpc": "1.0", "id":"curltest", "method": "walletcreatefundedpsbt", "params":[[],[{"mxV3ojsAHKuYHoDVqYczs6iPAfCCYESEDc":0.0001}]] }' -H 'content-type: text/plain;' http://user:password@127.0.0.1:18332/wallet/ColdWallet

result = {

    error =     {
        code = "-4";
        message = "Can't generate a change-address key. No keys in the internal keypool and can't generate any keys.";
    };
    id = curltest;
    result = "<null>";

}

Furthermore calling bitcoin-cli rpcwallet=ColdWallet getwalletinfo

returns:

{
  "walletname": "ColdWallet",
  "walletversion": 169900,
  "balance": 0.00000000,
  "unconfirmed_balance": 0.00000000,
  "immature_balance": 0.00000000,
  "txcount": 1,
  "keypoololdest": 1561077339,
  "keypoolsize": 98,
  "keypoolsize_hd_internal": 0,
  "paytxfee": 0.00000000,
  "private_keys_enabled": false
}

Is this a bug? Or am I doing something wrong?

I am using Bitcoin Core as a back end for an app I am developing and want the user to easily be able to create cold transactions using the keys they import into the wallet without having to specify a change address every time.


texts: What benefit does a non-mining client provide to the network?

texts: I know running a client will help propagate transactions around the network, but I also know a non-mining client will not contribute to the security of the network. Are there any other benefits of running a non-mining client?


texts: Do mining pools eliminate the need to store blockchain?

texts:
Suppose I want to design generic crypto currency miner starting from scratch . By generic I mean it can be configured to support a large number of available crypto currencies.

This generic miner must be able to connect to mining pools for the coins it supports in addition to being able to mine solo. In the case that it is configured to connect to mining pool , it does not need to store the blockchain on the PC on which miner is running? In this case the blockchain is stored on the server running mining pool? In this case the miner PC only has the current block?

The answers to above questions do not depend on wether the miner is configured to use CPU or GPU or both?


texts: Can a scriptPubKey have multiple addresses?

texts: When working directly with bitcoind, I can getRawTransaction for any transaction in the network. The vout has multiple outgoing addresses usually which contain a scriptPubKey. The scriptPubKey has a field called addresses, which is an array. I've only seen transactions with one address in this field. Is it possible to have more, if so, what does that mean?


texts: Strange LockTime values in Electrum transactions?

texts:
Electrum includes a locktime in all transactions by default.

Usually the value is equal to the current block height, eg 592918, however it sometimes drops perhaps 20 or so blocks.

What is going on here?


texts: Longer fake block chain with "valid" transactions

texts: What is preventing the bitcoin client from switching to a fake block chain that would be longer that current official chain? The faked chain would contain fictional transactions, but within the faked chain the transaction would be valid (e.g. like no double spends etc.).


texts: Reward schedule and maximum number of dogecoins?

texts:
According to Dogecoin's bitcointalk-thread there will be a maximum of 100 billion dogecoins. Yet, just below that figure is stated that the reward schedule offers a reward of up to 1 million dogecoins for each of the first 100k block, which would amount to 100,000,000,000 doges already rewarded for the first 100,000 blocks. The subsequent next 500k blocks would up the total doges to just shy of 170 billion dogecoins.

It also states that there will be a constant reward of 10k doges starting with block 600,001.

This information is inconsistent and I am wondering, how the reward schedule is actually implemented:
Is there a maximum of dogecoins or will the amount continue to grow infinitely as suggested by the constant reward?


texts:
My goal is to understand bitcoin.

I have read what happens during a transaction and have a question about it:

When a transaction happen, the miners compute a value called "prof of work". This value is calculated in order to get a 0 value (or something very closed to 0) for the hash of the value + the transaction + the last pow.

So the miner work is to calculate a prof of work. But i have read the miner discover new bitcoins too. Is it another form of mining ? I do not see the link between the POW calculation and the new bitcoins)

Thanks


texts: I currently have two offers for buying antminer s9. One with a 22nm chip and the other with 14nm. Can somebody give be the pros and cons for both, because i understand that the power consumption would be bigger with the 22nm, but will that mean that i will be mining less than the 14th/s -+ 5% ? or will the electricity be only different. Hoping to have a good response and answer from you, thanks.


texts: How should a Bitcoin Oracle verify a transaction prior to signing?

texts:
What are the specific parts of a transaction(s) that need to be signed in the "inheritance scripting sample".  Specifically, can someone provide more detail on what exactly is signed of the transactions?

I'm assuming there are approximately 3 transactions, but unsure of what is signed by whom, and the portion of the Tx that is/isn't signed.

1) The tx that is sent to a new address with the exact amount (published)

2) The tx that is created but with a time of 10 years (not published)

3) The tx that is created but pending some oracle logic (not published)

What I'm interested in is #3 and what does the oracle specifically sign?  What does that Tx look like?


texts: How to import address with private key using importmulti

texts:
Problem. importmulti function has a lot of parameters and they are more difficult to understanding then the parameters of another Bitcoin RPC-API functions. Those who are not profi in modern cryptographic achievements have difficult with understanding how to use importmulti function.

Here is the task that demonstrates the problem.
There is 2 wallets with the Bitcoin Core v.0.19.1:
wallet1 - the wallet with private key for export.
wallet2 - empty wallet into which we need to import the PK+address from wallet1.

So in the wallet1 we have the bitcoin address created by getnewaddress.

[root@wallet1 ~]# bitcoin-cli getaddressinfo 3M5e4QMBUYtpEewwuuoWCArpiM2fT4KEDy
{
  "address": "3M5e4QMBUYtpEewwuuoWCArpiM2fT4KEDy",
  "scriptPubKey": "a914d4b1b498c8be8813273937b834be6d9d1f488b9087",
  "ismine": true,
  "solvable": true,
  "desc": "sh(wpkh([675dc179/0'/0'/0']02607cb6c05a575fd040498ec8c44eabfa2a4f0fc320aeacf494a77b3a408d84af))#r6dvu4wk",
  "iswatchonly": false,
  "isscript": true,
  "iswitness": false,
  "script": "witness_v0_keyhash",
  "hex": "00144c88353345f2e03abc8e96b818fd030c3c9f59ab",
  "pubkey": "02607cb6c05a575fd040498ec8c44eabfa2a4f0fc320aeacf494a77b3a408d84af",
  "embedded": {
    "isscript": false,
    "iswitness": true,
    "witness_version": 0,
    "witness_program": "4c88353345f2e03abc8e96b818fd030c3c9f59ab",
    "pubkey": "02607cb6c05a575fd040498ec8c44eabfa2a4f0fc320aeacf494a77b3a408d84af",
    "address": "bc1qfjyr2v697tsr40ywj6up3lgrps7f7kdtvw6mnu",
    "scriptPubKey": "00144c88353345f2e03abc8e96b818fd030c3c9f59ab"
  },
  "label": "",
  "ischange": false,
  "timestamp": 1589545405,
  "hdkeypath": "m/0'/0'/0'",
  "hdseedid": "7cf768d4050dc142a69a149666798cc434045c6c",
  "hdmasterfingerprint": "675dc179",
  "labels": [
    {
      "name": "",
      "purpose": "receive"
    }
  ]
}

[root@wallet1 ~]# bitcoin-cli dumpprivkey 3M5e4QMBUYtpEewwuuoWCArpiM2fT4KEDy
Kwngf5FSYmHM5oPHjSoKxtHWUxXiQ5YN5ZR6shmzkYpMMftBh92c

I've tried to import that address to wallet2 but have failed.

[root@wallet2 ~]# bitcoin-cli importmulti '[{ "scriptPubKey": { "address": "3M5e4QMBUYtpEewwuuoWCArpiM2fT4KEDy" }, "timestamp":"now", "keys": { "Kwngf5FSYmHM5oPHjSoKxtHWUxXiQ5YN5ZR6shmzkYpMMftBh92c":0 }  }]' '{"rescan": false}'

result
[
  {
    "success": false,
    "error": {
      "code": -1,
      "message": "Missing required fields"
    }
  }
]

What the correct way to import that address using importmulti? Show the example please.


texts: How can Bitcoin transactions be traced if you can change your address?

texts: I understand in Ethereum you can trace it because wallet address never changes. But in Bitcoin you can change your address, no? Thanks.


texts: Run Bitcoin and BitcoinCash in same server

texts:
I use debian 9
I have compile 2 files:

bitcoinCashd -version
Bitcoin ABC Daemon version v0.16.2.0-6af5e93

bitcoind -version
Bitcoin Core Daemon version v0.15.1

So i need run in same server. Can some one help?

maybe need rename some executable files and connected both wallets on different ports?

Maybe good step by step manual


texts:
So I found my old mining wallet from 2012 that I earned some 0.5BTC on, but I'm having trouble accessing the file. I've tried following the instructions here (opening an old wallet.dat), but I'm running into an error using the pywallet program. It throws

File "pywallet.py", line 852
    _p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2FL
                                                                           ^
SyntaxError: invalid syntax

I've tried adding it into a new install of Bitcoin Core, but it appears as though I need to download the blockchain before it will scan my wallet as it isn't showing me any info about the wallet (like previous receiving address). Let me know if I can provide more information.


texts:
I wanted to install a dogecoin client on Debian and compiled myself. After starting it it stoped saying

Error: An error occured while setting up the RPC port 22555 for listening:  bind: Cannot assign requested address

I am sure that there is no other program using this port and IPv6 also works fine which I tested on my Apache server.

Hopefully you have an idea how to solve this.


texts: Need help about Mining and Difficulty levels!

texts:
I am new to these mining things and i want to know that, "What if the difficulty level increase?, would i make a loss with mining? I am mining $1 USD with 5MH/s server with the current difficulty."

Can someone shed some light on this matter? I will be very thankful to him


texts: How bitcoin exchange wallet system works?

texts:
I mean if exchange generate new address for each user (getnewaddress)(rpc) ...but trade just goes in database of their not on real blockchain ,so how does exchange deposit address shows 0 balance on block explorer after selling my btc to someone.

If the trade happens in database only then that address should contain balance linked to it


texts: What is the easiest to operate/fastest solo bitcoin mining client for a cluster rig?

texts: I'm planning to set up a rig and need a solo mining client. Can you offer me some suggestions? (Please don't just tell me that solo mining isn't worth it).


texts: Total Bitcoins in circulation on any given day?

texts:
I'm creating a spreadsheet to track total bitcoins in circulation from day 1.
This would be to add up each Bitcoin per day created and add to an accumulating total.
For example, if we picked any day we could then see what the total amount of Bitcoins created was.
If we picked the 1st January 2014 we could say the total Bitcoins mined equals X.
If we pick today (3rd June 2019) we could say the total Bitcoins mined equals X.
By definition, that would also mean we could calculate how many Bitcoins are left to be mined on any given day.
Could some one assist me to find the way to create this spreadsheet?
Thanks.


texts:
I'm running a private bitcoin network and would like to reset the bitcoin blockchain data back to the genesis block.

I've tried deleting all the files in ~/.bitcoin/blocks and ~/.bitcoin/wallets but bitcoin-cli -testnet getblockchaininfo still shows existing blocks.

$ bitcoin-cli -testnet getblockchaininfo
{
  "chain": "test",
  "blocks": 10,
  "headers": 10,
  "bestblockhash": "000000008668c111d16fd895919969836292a61919c6150a0f9a1dd5cc41aa55",
  "difficulty": 1,
  "mediantime": 1526598651,
  "verificationprogress": 6.116528714283428e-07,
  "initialblockdownload": false,
  "chainwork": "0000000000000000000000000000000000000000000000000000000b000b000b",
  "size_on_disk": 2573,
  "pruned": false,
  "softforks": [
    {
      "id": "bip34",
      "version": 2,
      "reject": {
        "status": false
      }
    },
    {
      "id": "bip66",
      "version": 3,
      "reject": {
        "status": false
      }
    },
    {
      "id": "bip65",
      "version": 4,
      "reject": {
        "status": false
      }
    }
  ],
  "bip9_softforks": {
    "csv": {
      "status": "defined",
      "startTime": 1456790400,
      "timeout": 1493596800,
      "since": 0
    },
    "segwit": {
      "status": "defined",
      "startTime": 1462060800,
      "timeout": 1493596800,
      "since": 0
    }
  },
  "warnings": "This is a pre-release test build - use at your own risk - do not use for mining or merchant applications"
}


texts: In order to send more hashes for mining do you need to connect into a bigger mining pool?

texts:
After the rate at which you can generate hashes, what determines the rate at which you can send hashes to be checked?

I'm guessing connecting into a bigger pool would help spread your load?


texts: Which address should be used to send the money as target?

texts:
We operate a market, there are sellers and buyers. Seller has Hierarchical Deterministic Wallets.  Seller give us the Xpub. Which address should be used as destination, when buyer wants to send money to seller?
I thought I should find the first address that has 0 balance. Do you agree with this strategy?


texts: Building a web app to collect Bitcoin payments. How should I monitor transactions on payment?

texts:
I'm looking to create a web app similar to coffee.foldapp.com where they load up a bitcoin address and once you pay it will automatically show the Digital code product. They seem to be using 0-confirmation. I heard it was risky, but why are they doing it then?

I'd like to do the same approach since my digital items aren't super expensive and have the option for zero confirmation.

What are some ways to do this? Does the client browser have to constantly ping the server to get a payment status update? Or does the server push it to the client's browser?

I'm planning to do this in PHP if its even possible. Or can I just do it without PHP and just tap into API's of other sites like blockchain.info?


texts: How divisible are ripples (XRP)? With 100 billion of the currency units being created at system inception one could assume that they are akin to satoshis, but during the operation of the system I found my balance being charged sub-ripple amounts for some operations. How much can one ripple be divided into?


texts: I have written a test for an open Bitcoin Core PR. Should I open a PR to the author's fork or wait for it to be merged?

texts:
I have written an additional test for an open Bitcoin Core pull request (PR). Should I seek to extend the PR by forking the author's fork of Bitcoin Core and opening a pull request to his PR branch? Should I wait for it to be merged and then open a new PR? Or should I suggest it in the comments of the PR and allow the author to add it to the PR if the author is happy with the test code I have written.
This question was asked by brikk on IRC and has been paraphrased.


texts:
I'm trying to understand how a bitcoin is valued. In my mind, it seems like it can be broken down with some basic math. For instance, if there is $50 trillion worth of "money" in the world and 1% of that money is in bitcoin, and there are 12 million bitcoins in existance, that would make a bitcoin 'worth' $41,666.67 in the physical world.

Is that a correct approach to identifying its value if I wanted to convert to/from dollars? Or, am I missing something?


texts:
Can anyone tell me how I would check the public address on my old Casascius Bitcoins? I have 3 total cons but I am unable to find where or how to check the public addresses on the coins for they only have 8 characters. I have listed all 3 of the pubic addresses below if anyone can help. Thank you in advance.

1) 134xRg9x
2) 1359wf1p
3) 1348FHtv

Thank YOU!


texts: Why can addresses be shorter than 34 bytes?

texts:
The wiki entry on Address says:

  Some Bitcoin addresses can be shorter than 34 characters (as few as 27 in theory) and still be valid. [...] These shorter addresses are valid simply because they stand for numbers that happen to start with zeroes, and when the zeroes are omitted, the encoded address gets shorter.

Alright, but according to this diagram, a main-network address is:

Base58Check(00 ++ RIPEMD160(SHA256(04 ++ pubkeyX ++ pubkeyY)) ++ checksum)

Next we look at the entry for Base58Check and we see step 4 is:

  4) Treating the results of step 3 - a series of bytes - as a single big-endian bignumber, convert to base-58 using normal mathematical steps (bignumber division) and the base-58 alphabet described below. The result should be normalized to not have any leading base-58 zeroes (character '1').

First strange thing - if it's treated as a single big-endian number, shouldn't prepending the main network byte of 00 not have any effect? Since that is the most significant byte it'd be like writing 00123 instead of 123 in regular notation, no?

Second strange thing - if the result should be normalized to have no leading zeroes, doesn't that mean that the output should never have any 1s in it? Step 5 seems contradictory to this

  5) The leading character '1', which has a value of zero in base58, is reserved for representing an entire leading zero byte, as when it is in a leading position, has no value as a base-58 symbol. There can be one or more leading '1's when necessary to represent one or more leading zero bytes. Count the number of leading zero bytes that were the result of step 3 (for old Bitcoin addresses, there will always be at least one for the version/application byte; for new addresses, there will never be any). Each leading zero byte shall be represented by its own character '1' in the final result.

It seems step 4 would have stripped out any possible leading bytes. However, in the case that it didn't, and for some reason it didn't with the prepended 00 byte, shouldn't an address have multiple leading 1s, e.g. 11175tWpb... instead of simply being shorter, e.g. 175tWpb...?

EDIT: Ok, it seems that what it is saying is that given payload X, base58(X) is normalized to remove the zeroes, and then you prepend a 1 for each leading byte of X, not base58(X). It still raises the question of why addresses are shorter instead of having multiple 1s. Is it that the RIPEMD160(SHA256(04 ++ pubkeyX ++ pubkeyY)) happens never to have too many leading 0s (which would be prepended as 1s) while base58(RIPEMD160(SHA256(04 ++ pubkeyX ++ pubkeyY))) does (and they are cut out of the final result)?


texts: Curious about a network-based double-spending attack

texts:
In their paper Two Bitcoins at the Price of One? Double-Spending Attacks on
Fast Payments in Bitcoin, Karame and Androulaki outline a particular race-attack that involves the slight control over a vendor's network connection (we need a direct connection to the vendor in this attack).  After reading it, I wondered why we couldn't connect more than one peer to the vendor.

Suppose an adversary A who owns many nodes on the network surrounds a vendor V so that V unbeknowingly is only connected to A.  That way, we could send a transaction to them, say, T_AV.  Then, when they broadcast that transaction to the network, they're just broadcasting it to the adversary, who would of course confirm the validity of T_AV.  In the meantime, so long as V isn't connected to the rest of the network they wouldn't know about the double-spend.  This would make for an attack that has feasible hardware requirements, and isn't hindered by fast transactions.

Am I missing something or would this attack work?  I'm also curious what kind of measures Bitcoin takes to prevent the controlling of someone else's connections, and what kind of counter-measures attackers have used to control someone else's connections, if any.


texts: Is 8 the maximum number of incoming peer connections?

texts:
The reference here for running the bitcoin daemon does not really clarify what maxconnections mean.

maxconnections=  Maintain at most  connections to peers (default: 125)

Is this the max connection for all inbound and outbound peer connections? Or is it just to one or the other? If I understand correctly, inbound connections are others trying to connect to your node for information (e.g. transaction) propagation, while outbound connections are your bitcoin daemon node connecting to others for information.

Here's another reference in one of the posted answers that stated 8 outbound peer connections is the max; it seems to imply that the number of outbound peer connections is unconfigurable. Furthermore, that maxconnections only controls the number of inbound connections and not outbound. Is this true?

I don't intend on being connected to by other peers (this decision is rather selfish, but that's besides the point), so I've blocked port 8333. I believe, effectively, blocking port 8333 will only stop peers from connecting to me (stops inbound) and not me connecting to peers (does not stop outbound). Is this right?

What implications do blocking port 8333 have on my bitcoin daemon from getting transactions? Does it get less transactions or get transactions slower? I've been noticing that for relatively long stretches of time (e.g. 20 seconds or so), sometimes I see no transactions come through.


texts: Is there a newer Bitcoin blockchain download available?

texts:
The SourceForge project page for Bitcoin provides a blockchain download at http://sourceforge.net/projects/bitcoin/files/Bitcoin/blockchain/ but this file is old/dated.

How and where can I download an up to date copy of the Bitcoin block chain?


texts: Cryptocurrency Arbitrage - What do I need to know?

texts: I'm curious as how one would go about arbitraging crypto currencies - How does it work? what do I need to look out for? What are the risks and caveats?


texts: How can I temporarily move my value to something other than bitcoin without providing identifiaction?

texts:
Bitcoin is in a bubble right now, I would like to sell them as I believe the value will drop within a couple of days. I tried registering an account on mtgox, but it's complicated and they seem to have some problem to keep up with registrations(my account isn't confirmed yet)

I want to sell my bitcoins so I can trade them back. I looked at litecoin, wich seems like a nice option, but their value has also gone up a lot the last couple of days, relative to bitcoins. Are there any other options available?


texts: Restore a wallet from an external drive?

texts:
I have an external drive where at some point I did a complete backup of my (linux) home directory.

There's a directory .bitcoin.

I now have a computer, and I just installed bitcoin-qt and other stuff. I started it and it generated a new receiver address.

If I copy the old .bitcoin directory from the external drive to my current new home, will it work?


texts: How would these parameters affect mining and the size and content of the mempool?

texts:
Q1 and Q2 are theoretical questions to confirm my understanding.  I know doing the following serve little practical purpose.

Q1: If a mining pool were to set blocksonly=1 in their bitcoin.conf, would all blocks created be "empty blocks" (only the coinbase transaction)?

Q2: If a mining pool were to set mempoolminfee very high, would all blocks created be "empty blocks" (only the coinbase transaction) or possibly only a few transactions?

Q3: I can't seem to find the syntax to put mempoolminfee in bitcoin.conf.  Any help appreciated.


texts: Blockchain synchronization is painfully slow / Best way to download blockchain

texts:
I'm trying to setup my own Bitcoin node on Ubuntu 16.04.1 LTS.

Right now, I've stuck with blockchain synchronization. I'm letting bitcoind to run every day for at least 10-12 hours while I work and it already takes three days to download 83% of the entire data.

I have very good Internet connection, it should take no more than two hours to download 80 GB of data, however, it's taking at least 30 hours already. My connection is practically free from other downloads most of the time.

I've googled this problem: some people say that current version of the bitcoind is so fast that it doesn't matter how blockchain is downloaded throught the Bitcoin network or by torrent. Other people say, that it takes a week to download the entire blockchain.

Is there a way to optimize my setup to make it download blockchain much-much faster?
Or do I better download it via some torrent and then synchronize the differences from the network? What is the best place to find such torrent file or magnet link? Also, is it safe to download blockchain from some third-party, will bitcoind validate it?

SO, generally speaking, what is the best way to download the blockchain in order to setup a working up-to-date Bitcoin node?

$ cat /etc/issue
Ubuntu 16.04.1 LTS \n \l

$ uname -a
Linux destiny 4.4.0-47-generic #68-Ubuntu SMP Wed Oct 26 19:39:52 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

$ bitcoind -version
Bitcoin Core Daemon version v0.13.1.0-g03422e5


texts: Multibit HD Wallet Stuck For Days (Unconfirmed)

texts:
So MultiBit HD Wallet has been stuck for days and it's killing me. I've repaired the wallet numerous times but no luck. How can I proceed? 2nd time in the last week this has happened.. last time I was able to fix it. So I think I'm going to move wallets. Not very educated on the matter. So if anyone can tell me how to move my keys to a new wallet that would be great. Suggestions?

Image: 1


texts: Where can I view my HD wallet seed in bitcoin core 13.2

texts: Where/how do I view my seed in core 13.2? I understand that as of 13.0, the hd wallets are used by default.


texts: BTC-e international wire transfer in USD from Russia

texts:
I tried to make a wire transfer in USD, but the bank refused. Their reason was that the supporting documents should be provided for such transaction.
Payment details which BTC-E provides do not contain both the basis and the reason of the payment (which should be specified too). As far as I know any wire transfer to a company from a person should be supported with documents.
Has anyone made a successful wire transfer from Russia with those details?


texts: Create custom Transaction ID using Bitcoind raw transaction

texts: I would like to know if it's possible for someone to create a raw transaction using bitcoind or bitcoinJ and predict the Transaction hash.How exactly is the transaction ID(hash) calculated ?


texts:
Hello Friends is this possible to reverse the elliptical curve if you have value of X and Y of public key?
I know the public is generated through following formula
K=kG or kG=K
Can we reverse it ?


texts: What do people think lies in store for the future of mining coins from the point of view of both pooled mining and mining individually?


texts: What happens if "transaction size" is larger than "maximum block size"?

texts:
Assuming a transaction size is T Bytes, while maximum block size is B Bytes, such that T>B.

What happens for this transaction?

It will be divided into two smaller parts and will be stored in two separate blocks? Or it will not be confirmed at all? Or A dynamic block size could be used ?

P.S. Although, actually maximum block size is 1 MB and seems to be enough for every transaction; however, we would like to know the strategy of the Bitcoin in such a situation.

Note: Since in addressed answer is mentioned: "What limits transaction size is cost." the question does not seem to be the same, where my question is not what is the maximum size of a transaction, but is what happens if size of a transaction is larger than maximum block size.


texts: How does walletexplorer.com generate the wallet ID's?

texts:
I was wondering how Walletexplorer.com determines what the wallet ID(entifier) of a certain set of adresses ( wallet ) is.

There seems to be no preset like the case with adresses (eg, they all start with 1....X)

more something like

0020bb2aef
5dbe0f39c2
43ba59ffbc
71cffa7b7f

But rather seems to be "randomly" generated.

Could anyone explain if this is the case, or if it's indirectly generated from something such as the private key, as the case is with normal adresses.


texts: Bitcoin uses UNIX time for timestamp. Unix Time is really accurate. I want to know why there is a "70 minutes" offset is allowed in Bitcoin network adjusted time. Is there any distribution used to get to this "70 minutes".


texts:
Some pools / payout mechanisms are vulnerable to pool hopping.

Is P2Pool vulnerable?


texts: What is the approximate hashrate of a human?

texts:
Which and how much mathematical operations are required for the blockheader-to-blockhash operation and how fast would a human be able to calculate a single hash?

EDIT: For simplicity, I think it's a good idea to use the world record for mathematical calculations to make it a little more fair.


texts: Why seed from BIP39 mnemonic phrase is much longer than entropy?

texts:
BIP39 converts mnemonic
"zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo zoo wrong"

to the fairly long seed
"b6a6d8921942dd9806607ebc2750416b289adea669198769f2e15ed926c3aa92bf88ece232317b4ea463e84b0fcd3b53577812ee449ccc448eb45e6f544e25b6"

Good tool to play around https://iancoleman.io/bip39/

What's the point of so long seed value when the entropy value of random 12-words mnemonic is much smaller?

2048 words list dictionary = 2^11 => 11 bit
12 words * 11 bits = 132 bit
in hex format (4 bit for character) is 132/4=33 charter long, vs 128 of seed


texts: A few security-related questions: how do I automate a web service as much as possible without storing private keys on server?

texts:
I'm learning how to use bitcoind, and want to set up a side project that uses bitcoin to learn along the way. I'll be using the json-rpc with PHP on my server. I want to create a service that will receive bitcoins from users, and will eventually send those bitcoins either back to the users or to my own wallet.

In order to keep things secure, as soon as coins arrive at a user's unique address, I want to automatically forward them to another wallet that doesn't have the private keys on the server.

My questions are thus:

What's the easiest way to handle the bitcoins from an off-server wallet (on my computer or such), without doing absolutely everything by hand? Would it be possible to write a script that does everything I want it to do with the off-server coins, after prompting me for the private keys? For example, a database could hold all the bitcoin commands that would need to be run, but it would need by "OK" to run (requiring the keys). Would the keys be somehow visible if someone got access to the server?
If not the above method, how else can I automate the process as much as possible? The only thing I can think of currently is to do everything by hand: have a private wallet on my home computer, seeing what to do with bitcoins on various addresses, and manually sending them out using my home bitcoin client to the required addresses. This would be extremely tedious with a lot of users on the service. Surely there's a better, secure way?
I don't want to keep private keys on the server for two reasons: a) I don't know anything about server administrations or server security, as I'm just a developer, and b) as a result, I have a managed server (managed by the host), so they could get into the server at any time. I'm wondering, can anyone suggest how to get started in server administration and security so that I can take it into my own hands?

Thank you.

EDIT: To clarify, I mean handling transactions that are off of the server, not actually in "cold storage." The off-server wallet could be hosted on my personal computer--I just don't want it on the server, since it's more prone to attack.


texts:
Bitcoin Core is eventually going to replace OpenSSL with libsecp256k1 for all ECDSA operations. As I understand it, this is motivated by wanting consensus-critical rules to not depend on OpenSSL.

Is libsecp256k1 signature verification also faster than OpenSSL? I've heard conflicting information about that.


texts: Is there a list of charities that accept Bitcoin donations?

texts: Say someone wanted to donate some of their Bitcoins for charity, is there some comprehensive list of charities that accept donations in Bitcoins?


texts: Is there only one method? for miner and pool communication?

texts: I tried doing some sort of filtering on XMRig using wireshark on an ETN pool and I found that XMRig was using login method of JSON-RPC 2.0, my question is does all miners use this method? By "all" I mean even the bitcoin, monero and all minable cryptocurrency miners use this method? I heard about GBT, stratum and getwork, are they just a simple "sub-part" of JSON-RPC?


texts: Is there a limit to how many blocks can be rolled back from a 51% attack?

texts: I was wondering if we where to ever face a 51% attack is there some sort of limit as to when the longest chain doesn't matter? For example if I owned 51%+ of the network, mined 1000 blocks privately and the rest of the network was at block 990 and then I broadcast the data would everyone switch to my chain and would the last 990 blocks be orphaned?


texts: Why do I get -4 error code from Bitcoin RPC

texts:
I'm directly dealing with Bitcoin RPC and my first step is loading wallet. At first I try to check listwallets to find the current wallet there. If not, trying to load wallet:

Post body = {"method":"loadwallet","params":["aaa34f5c59305e2a13d5438e0ce*****"],"id":"jsonrpc"}
Address = /wallet/aaa34f5c59305e2a13d5438e0ce*****

Sometimes as a result of loading request I get:

{"result":null,"error":{"code":-4,"message":"Wallet file verification failed: Error loading wallet aaa34f5c59305e2a13d5438e0ce*****. Duplicate -wallet filename specified."},"id":"jsonrpc"}

So, this results in error, but after some time (a couple of minutes) listwallets contains my wallet (aaa34f5c59305e2a13d5438e0ce*****). What did happen?

I also noticed that listwallets always contains 50 results. I didn't find in the documentation about this limit but it can be somehow related.


texts:
I have read about a change address and wondered why there even is the concept of change?
Let's say I received 1 BTC from some person A and I want to send 0.4 BTC to another person B, afterwards. From what I have understood, I have to send the 1 BTC, as a whole and then get 0.6 BTC as change.
Is that right? And if so, why don't you just send 0.4 BTC in the beginning?


texts: How can I create a new wallet on Bitcoin Core?

texts: How can I create a new wallet on Bitcoin Core (Bitcoin QT)? I forgot my old password, so I can't create transactions using the old wallet. I don't have money on my old wallet, I just need to create new wallet without the forgotten password.


texts: Why do you need to send a transaction out with NXT to secure your address?

texts:
When setting up an NXT account, it is recommended to send a transaction out in order to secure your account. I don't quite understand why it's needed. I know that if you don't send one out, your account is only 64-bit encrypted and when you send it out, it becomes 256-bit encrypted. I don't see how that makes a difference as you can still brute-force it regardless given an amount of time.

Why is it necessary to encrypt it when sending an outgoing transaction compared to just receiving one?


texts: What does "Green address verification" mean in the context of transaction validation?

texts: I am only new to Bitcoin and I would like to know what a "Green address verification" is. I have an Electrum wallet ver 3.3.6 and I think the term is being used in the context of faster transactions but I am not sure. Any info would be appreciated.


texts: Is there an easy explanation to understand the different types of pools

texts: I would like know if there is an easy explanation on all the different pool systems, their reward systems and how fast they pay without being referred to the Meni Rosenfeld paper


texts: Is 165aBmgtQJFDLkSYPU5C8jq5gpnAtHdKBh a scam Bitcoin address?

texts:
Is this bitcoin address authentic: 165aBmgtQJFDLkSYPU5C8jq5gpnAtHdKBh

I sent BTC to the address for Paypal funding but no response from them since yesterday.


texts: What is the order of block hashes in block-locator array?

texts:
I have to compose a "getblocks" command found in https://en.bitcoin.it/wiki/Protocol_specification#getblocks

The "getblocks" command contains the "block locator hashes". In essence, I inform a remote node of block hashes that I'm aware of already. There is a rule of how to construct the block locator. Except I’ve no idea of what “pushing”, “going back” or “newest back” means. I cannot figure out the order of block hashes in what I call a locatorArray.

Let’s assume I want to advertise three block hashes:

Block hash of block number zero.
Block hash of block number one.
Block hash of block number two.

Let’s assume I have an array of three elements. For example, I might walk through the array in a for loop as follows:

for ( int i = 0; i < locatorArrayLength; i++ )
{

}

The block hash of which block number should be in locatorArray[0]?
The block hash of which block number should be in locatorArray[2]?


texts:
BIP65 discusses replacing the ntimelock field with the new CHECKLOCKTIMEVERIFY OP code:

  As an aside, note how if the SignatureHash() algorithm could optionally cover part of the scriptSig the signature could require that the scriptSig contain CHECKLOCKTIMEVERIFY opcodes, and additionally, require that they be executed. (the CODESEPARATOR opcode came very close to making this possible in v0.1 of Bitcoin) This per-signature capability could replace the per-transaction nLockTime field entirely as a valid signature would now be the proof that a transaction output can be spent.

How is this different from the functionality of ntimelock? (I.e. Why would a signed transaction using ntimelock not be sufficient?)


texts: Calculate block hash is different in regtest?

texts:
I'm able to calculate the block hash in mainnet and testnet, but I don't get the right hash in regtest.
I mint +3000 blocks and I get the block with height 3000
bitcoin-cli getblock $(bitcoin-cli getblockhash 3000)

{
  "hash": "4221d8b10b0a7eb5e050337c76819abf71113f17e266e88cb12df4bf5ce24b55",
  "confirmations": 502,
  "strippedsize": 215,
  "size": 251,
  "weight": 896,
  "height": 3000,
  "version": 536870912,
  "versionHex": "20000000",
  "merkleroot": "23b4600b467f18ef0ec18bd73a9b921077486cf67c44c912de114888db184bf9",
  "tx": [
    "23b4600b467f18ef0ec18bd73a9b921077486cf67c44c912de114888db184bf9"
  ],
  "time": 1599147354,
  "mediantime": 1599147353,
  "nonce": 0,
  "bits": "207fffff",
  "difficulty": 4.656542373906925e-10,
  "chainwork": "0000000000000000000000000000000000000000000000000000000000001772",
  "nTx": 1,
  "previousblockhash": "4776b1ccad27e2de9ccbdc5bf4ad4d972a89e27a020db1f7b59abb857d77f3be",
  "nextblockhash": "121512fc6bc1395ada64a6c63ba2c2955ad9cc240a1fc0282b95cf2c2651b381"
}

Now I save the values in env variable
 ver=`printf 20000000 | tac -rs ..| tr -d '\n'`
 prev=`printf 4776b1ccad27e2de9ccbdc5bf4ad4d972a89e27a020db1f7b59abb857d77f3be | tac -rs .. | tr -d '\n'`
 mkl=`printf 23b4600b467f18ef0ec18bd73a9b921077486cf67c44c912de114888db184bf9 | tac -rs .. | tr -d '\n'`
 time=`printf '%x\n' 1599147354 | tac -rs .. | tr -d '\n'`
 bits=`echo 207fffff | tac -rs .. | tr -d '\n'`
 nonce=`printf '%x\n' 0 | tac -rs .. | tr -d '\n'`

After that I can concat and get the little endian representation
printf $ver$prev$mkl$time$bits$nonce | xxd -r -p | sha256sum -b | xxd -r -p | sha256sum -b | awk '{printf $1}' | tac -rs ..

The result is: 09665bcb63b6c279948f93937669bf1c8f36cffda0646180ba523847cb642384. the same operations in mainnet and testnet works properly.


texts: "If there is no one company behind bitcoin, who controls it?"  This is the question that many people new to bitcoin ask. What is the best way to convey to them how bitcoin works, and in a way that can be understood by non-techies.


texts: Could decentralised proof of time in BCHSV solve for high PoW power consumption?

texts:
0-conf requires decentralised consensus of time in order to determine the order and time of each transaction.

Bitcoin has a block time of 10 minutes achieved by brute forcing hashing algorithms of variable difficulty at enormous scale with a difficulty optimised for it to be solved in ~10 mins. This is what gives the currency its security.

With decentralised time consensus such as that required for 0-conf, would it not theoretically be possible to enforce a 10 minute block time by instead implementing the following conditions:

Each block submission must contain at least one transaction that has been entered 9mins 55secs after the previous block (ie: No incentive to mine until 5 seconds before 10 min block time)
Difficulty optimised to allow the network to solve the block within ~5 seconds
In the case of conflict within the 5 second challenge period, lowest hash in bit value wins
In the case of conflict after the 5 second challenge period, first hash wins
Network decides any further split in consensus thereafter by longest chain as it does now

Assuming this would be doable, would it not technically be possible to secure Bitcoin with the same hashrate it has now, but consume 0.0083% as much power, and make mining far more profitable for miners (especially in countries that don't have cheap energy) with no loss of security?


texts: Are there any resources for creating your own coin?

texts: I have some experiments I want to do for creating my own coin. I've seen stuff like coingen.io but I want to do it myself. I also will be messing with other things like the hashing algorithm. Are there any resources out there that gives a bit of guidance through this process? The best I've got so far is taking the dogecoin(or any other altcoin) first commit and comparing to the litecoin source. But this didn't produce very good results for me


texts:
I would like to ask the following. I've downloaded Bitcoin Core and just start using their "Console". Before I can createrawtransaction, I need to first set up a node in Bitcoin Core, right? If yes, I did follow the instruction in https://developer.bitcoin.org/reference/rpc/index.html.
However, when I want to apply a node for myself that is using --> addnode "167.172.250.161:8333" "onetry"
but end up is Null although I have requested for "getnodeaddresses" as per the screenshot:

Please advise as I need to "importprivkey" in order to perform the createrawtransaction.
Also, my apology I would like to ask this as well. Why when I send createrawtransaction in the Bitcoin Core Console, the error it states here that the error - Method not found (code -32601). Anyone can advise or provide guidance to me? I'm no expert in this. Thanks in advance.


texts:
I am testing out the BitMap API, and my get function to get the ticker looks something like this

 r = requests.get("https://www.bitstamp.net/api/ticker/", proxies=self.proxydict)
        if r.status_code == 200:
            return r.json()
        else:
            r.raise_for_status()

However, I notice the "last" price it returns is always a little different than the one shown here (https://www.bitstamp.net/) Is the API realtime? Or is it lagging behind the actual price.

Thanks!


texts: How to spend from a custom P2SH script using bitcore-lib

texts: My Javascript/typescript project uses bitcore-lib. It uses Script.buildScriptHashOut to build custom P2SH outputs. How do I spend from this custom output?


texts:
I'm setting up a p2pool server to mine Scrypt-based coins on.  Mostly just for myself, but occasionally some friends will jump in.  I'll mostly be mining newer coins with very low difficulties.  I'm wondering whether I'd get better results by:

Locating the server at home with my mining rigs, which would give extremely low latency from the rigs to the p2pool node, but higher latency from the server to the internet through my crappy home DSL connection.

or

Locating the server in a datacenter, which would give higher latency from my mining rigs to the p2pool, but lower latency from the p2pool server to the internet.

I guess the question boils down to "For maximum mining performance, is it better to minimize latency from the mining rigs to the p2pool server, or from the p2pool server to the Internet?"


texts: Would free energy cause a market collapse?

texts:
Consider a world where energy is free and plentiful. Bitcoin, and other cryptocurrencies, are given value since they are 'proof' of work. This work comes at the cost of:

a. time
b. energy

By removing the cost of electricity, hardware expenditure becomes the ceiling for hashrates. Surely this makes cryptocurrencies less valuable. Wouldn't the market become hypersaturated as supply went up? On large enough scale, hardware turnover rates might provide some limiting factor to supply- but for the most part mining operations should be able to keep up with the increasing difficulty of the hash.

I can see otherways the blockchain would be useful, but I'm starting to wonder whether cryptocurrencies would continue to work.


texts: When thinking about e-currency in a general sense, what features discourage black market usage, but promote anonymity?

texts:
I'm interested in e-currency that discourages black market usage (child porn, meth deals, etc) but allows for anonymous operation (donations to charity, buying a pizza, viagra, or other health issues)

What pre-existing work exists that researches applicability of various "controls" into e-currency systems such as e-cash, Bitcoin, Open Transactions, etc.  And by "controls" I mean:

Psuedo anonymous user registration
Usage "escrow" allowing third party audits or reviews of transactions
Anything else that would be resisted by the Bitcoin purist.

I'm interested in any example you can think of, links to Bitcoin Talk, or any other whitepaper that discusses ways to legitimize e-currency to a moderate fiscal conservative.


texts: Are Bitcoin and Ethereum really de-centralized? Or is federated a better term?

texts:
By looking at the bitcoin and ethereum mining pool hashrate distribution I feel that only 5-10 relevant full nodes exist. So it's more like a federated system among those.

Am I seeing something wrong here?


texts: How can the number of peers from the same IP address be counted?

texts:
A Bitcoin client connects to peers and can accept connections from peers.  Is it possible to learn how many nodes exist from a specific IP address?

Specifically, the monitoring service from RowIT ( http://bitcoinstatus.rowit.co.uk ) gives a metric "Total Hosts", but I suspect that if there was more than one host from an IP address, the second and successive hosts would not be counted in the total.


texts: What are cash outlays & expected inflows for an individual miner?

texts:
I'm a student and a beginner interested in learning about Bitcoin. I am not interested in attempting to mine at this time, but I would like to know more about how it works.

Per my understanding, adding to the blockchain requires brute-force computing. I know some amateurs attempt to mine with relatively simple setups, spending maybe a few thousand dollars to get the necessary equipment. I also know that others spend significantly more to create complex setups that, all else equal, I would assume are much more effective.

Generally speaking, what are some estimates for what people might spend to get set up to mine bitcoins? Given what people might spend, what might they expect to earn in a year if constantly mining? What I'm most interested in knowing, for context, is what type of an "investment yield" does the average miner generate? For example, if I spent $5 on equipment and earned $25 in a year, my return would be 20%.

Thanks for your thoughts!


texts: I'd like to know what's the probability of a sybil attack and if there are mechanisms built in to prevent this kind of attack?


texts: Is it technically possible to change the total amount of Bitcoin?

texts: Also, is it possible to change the reward cycle duration or the number of mining- reward coins?


texts: Can't connect to rpc.blockchain.info with bitcoin-cli

texts:
I'm trying to, given a bitcoin address, retrieve the last X transactions to this address. After researches, I found this to be an interesting solution, as I don't want to download and validate the entire blockchain for this simple purpose.

On my Windows 10 machine, I downloaded bitcoin-core and tried to send a getinfo (I didn't execute bitcoin-qt as I don't want it to start syncing with the blockchain) :

./bitcoin-cli -rpcconnect=rpc.blockchain.info -rpcport=80 -rpcuser=my_id -rpcpassword=my_password getinfo

I got an error message complaining about bitcoin.conf and credentials (indeed, there was no bitcoin.conf file in %APPDATA%\Roaming\Bitcoin\)

So I created a bitcoin.conf file :

server=1
rpcuser=my_id
rpcpassword=my_password
rpcport=80
rpcconnect=rpc.blockchain.info
#rpcssl=1        #SSL mode for RPC is no longer supported

However, I get this error (bitcoin-cli has been allowed to access the web in Windows Firewall) :

error: couldn't connect to server: EOF reached (code 1)
(make sure server is running and you are connecting to the correct RPC port)

Has the service been discontinued ? Or is there a problem with my configuration ?


texts: How is Bitcoin/Blockchain programmed to do multi transaction at the same time?

texts:
I read this article blockchaing stored and now I am bit confused. In this article it is described, that the transaction needs 15 seconds to propagate to the whole blockchain network. I know that the new transaction block contains the hash of the previous block. So my question is, if anyone in this 15 seconds create another transaction, how the systems doesn't crash?

To make my question a little bit more clear, I make one example. Let's say the hash of the previous block was "11b83f1dbb421b7539f755". If I make a transaction (Transaction A) for about 1 BTC and 1 second after me someone other makes new a transaction (Transaction B), which transaction becomes the previous hash "11b83f1dbb421b7539f755", because it needs 15 seconds till every node knows the new chain? So after one second not every node, knows about the Transaction A.

Thank you very much in advance!

PS: English is not my mother language :)


texts: How can I make Bitcoin start with a simple `bitcoind` in the terminal?

texts:
When I want to start Bitcoin I have to use /opt/bitcoin/bin/bitcoind to start it. How can I use simply  bitcoind to start it?

I am using centOS 7.


texts:
I've been using BTC for years now. This is the first time this has happened.

Woke up yesterday to an unconfirmed transaction of around $30. Completely confused, I wondered where this came from.

Anyway, it's been 30+ hours since receiving the funds. Still not confirmed, and still completely confused.

My question really, could this be fraudulent BTC? How the hell did they get my address, and how long until I could possibly see this confirmed?

Txid: 987ee6a4930d7610ea081250dfc49d4fdd0ade093d740b4c18c5f78db2bc05c7


texts: Bitcoin Transaction Fees - Want to increase fees!

texts:
I have my bitcoins on bittrex and I want to pay with increased fee to make sure its confirmation in the least possible time. I don't know how to do that.

In plain words, I want to deposit Bitcoin to my local exchange but bittrex is allowing only 0.001 BTC transaction fees. I want to increase it.

I thought that I'd purchase other altcoins like NEO or LTC and transfer it to other exchange first but so far, I am unable to find any exchange that allows "increasing transaction fees".


texts:
UPDATED AND CLARIFIED AND SIMPLIFIED

I'm looking through npmjs.org - My thought is can a node.js server mine (without a graphics card just using its own possessing power?) If so (there are a lot of modules for different things to do with statum) has anyone else done this?

I'm having difficulty understanding things with these npm modules on how to get them hooked up the same as my batch file (.bat) currently using cgminner ( I don't want to use cgminner just node.js)

my .bat for cgminer looks something like this:

cgminer.exe --scrypt -u example.1 -p x -o stratum+tcp://united.wemineltc.com:3334 --gpu-platform 0 -w 256 -v 1 -I 17 -g 1 -l 1 --thread-concurrency 6496

does anyone use node.js for this
can someone show me which npm modules mine
can someone show me how to add my bat details to a npm node module js script

Thanks Guys!


texts:
Given the transaction below, how can I -

Identify this tx involves multisig
What tool/s can I then use to calculate the resulting multisig address

The second HEX address 9d07acef34e0ad5a54f92aae65f49e2f3a24dd39 is easy enough - Base58Check converts it to 1FKJHRVHmyvjDfVbPuBW9e1tdCgt2XWtCb. I can follow the technical background for standard addresses at https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses

To calculate the multisig address I can use bitcoind to decode the raw tx:

./bitcoind decoderawtransaction 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

"vout" : [

    {
        "value" : 0.00100000,
        "n" : 0,
        "scriptPubKey" : {
            "asm" : "OP_HASH160 f815b036d9bbbce5e9f2a00abd1bf3dc91e95510 OP_EQUAL",
            "hex" : "a914f815b036d9bbbce5e9f2a00abd1bf3dc91e9551087",
            "reqSigs" : 1,
            "type" : "scripthash",
            "addresses" : [
                "3QJmV3qfvL9SuYo34YihAf3sRCW3qSinyC"
            ]

But this took over 6 seconds to complete.

Is there an easier/quicker to simply calculate a multisig address?

The raw tx:

{

  "value":"0.00100000",

  "scriptPubKey":"OP_HASH160 f815b036d9bbbce5e9f2a00abd1bf3dc91e95510 OP_EQUAL"

},

{

  "value":"0.09890000",

  "scriptPubKey":"OP_DUP OP_HASH160 9d07acef34e0ad5a54f92aae65f49e2f3a24dd39


texts: What does this phishing website compromise?

texts:
Earlier this day, I have received an email saying that there is a buyer for my localbitcoins advertisement:

However, the https://localbitcoins.com/ads/37726/103702 link shown actually links me to:

  http://mandrillapp.com/track/click.php?u=30106122&id=8f52703cd0ec4b2b81e069630069dbdc&url=http%3A%2F%2Fllocalbitcoins.com%2Faccounts%2Flogin&url_id=ad428ed9d64304239644387c1388db2f686a98ca

I've accidentally clicked it and it brings me to a phishing website which looks identical to localbitcoins. The phishing website is hosted on http://llocalbitcoins.com (whois record). Notice that there are two "L"s in the domain name.

Wwhat does the hidden link do? Now that I've clicked the link, what can happen to me?

I've changed my password since then. But what else can I do to protect myself?


texts:
As Peter Wuille mentions here, the ECDSA signature values (r, s) are modulo N (eg verifying ECDSA signatures, where u1 = z * w % N), whereas the rest of the ECDSA functionality in Bitcoin seems to be modulo P.

Why is this so?


texts: What advantages do "alt-coins" have over bitcoin?

texts:
I'm struggling to see the importance of alt-coins. It seems to me that one of the major selling points of the various alt-coins is their quicker confirmation times. The common argument is: this is good for merchants and the like, because there is less time for them to worry that the customers' payments are legitimate.

But can bitcoin users not have the same "luxury?" Why can't a merchant run his own node? His node will process the transaction, and the rest of the network can play catch-up.

Another argument is that there are too few bitcoin, and that eventually bitcoin will be the gold of digital currency--what the big transactions happen in--and the alt-coins will be the silver, or the copper--for day-to-day use.

Is that really even good in theory though? The price of bitcoin would need to be in the millions for that to even be a decent worry. I can possibly see it being an issue, but do we really need to consider it now, when the exchange rate for bitcoin hasn't seen more than a few months in the 4-digits?

Am I overlooking a hyper-important advantage?


texts: For a non-technical person, how do I generate a ECDSA key pair easily?

texts: I want to know because I would like to generate a vanity address at Vanity Pool.


texts: Which is the correct value for Tx version in tx messages of bitcoin pcap?

texts:
Recently, I researched TX messages in the bitcoin protocol and captured some bitcoin traffic in which the version field of a TX message in a specific packet was 2. The Transaction page of the Bitcoin wiki mentioned that the tx version is currently 1.
I checked out that packet and I found that it is a valid packet and its value and the generated output address from that tx message is valid.


texts:
I don't understand, how multi-sig signatures are generated.

I've seen that inputs redeeming a multi-sig output, can be signed and signed over repeatedly, with different private keys using bitcoind's signrawtransaction, as it is done here.

But like this, the more and more signed transaction would need to be passed around among the different parties of the multisig.

Isn't it also possible to let the different parties of the multi-sig, individually produce their signatures, send them to one place, where they then are assembled to a scriptSig redeeming the multi-sig output?


texts:
2013-06-29 15:23:31.791000  Local: 0H/s in last 0.0 seconds Local dead on arrival: ??? Expected time to share: ???
2013-06-29 15:23:31.791000  Shares: 0 (0 orphan, 0 dead) Stale rate: ??? Efficiency: ??? Current payout: 0.0000 BTC
2013-06-29 15:23:31.791000  Pool: 605GH/s Stale rate: 18.0% Expected time to block: 1.8 days

What does this all mean and why are there '???'s?


texts: Can I add inputs from different accounts coming from the same Bitcoin HDWallet?

texts:
Say I have 1000 users, each one with its own account with paths m/49'/0'/{user.id}', and I am controlling received/sent funds.

Could I collect all the funds (i.e. inputs) in a sole fat transaction output even though they belong to different accounts of the same HD Wallet?


texts:
For example, I have link:
bitcoin:1DF9jgzftTFn4ZnDV2YEjUtZ4uHtBywj57. If user open this link in browser, bitcoin address automatically insert in address text field. Example for my MultiBit Classic client:

But what should I make in link to have been autocomplete not only field Address but also fields Label and Amount?

Thanks.


texts: Can you give me ideas for interesting Bitcoin-related events/projects that I could launch at my university in order to attract people to the club?