texts:
I have been wondering how trading fees are actually calculated e.g. Kraken takes 0,35% of every trade. Does this fee apply both when I buy bitcoins and later when I sell them?

Furthermore if I choose to open a position of lets say $100, and leverage on 1:3, is the fee calculated as $100 * 0,0035 or as $300 * 0,0035?

Thanks in advance


texts:
Reading this section of BIP144, I noticed the followng statement:

  Parsers supporting this BIP will be able to distinguish between the old serialization format (without the witness) and this one. The marker byte is set to zero so that this structure will never parse as a valid transaction in a parser that does not support this BIP. If parsing were to succeed, such a transaction would contain no inputs and a single output.

And this is in fact confirmed by this line in Bitcoin Core which is executed for every transaction found in a block during the CheckBlock call.

As far as I understand, this should mean that old clients that see a block containing a SegWit transaction would consider that transaction invalid and hence discard the whole block. Is that correct? What am I missing?


texts: How can I determine the address from a private key?

texts:
From the steps in the wiki, take this example private key:
0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D

When I import this into Electrum, I find these values:
Address:
1GAehh7TsJAHuUAeKZcXf5CnwuGuGgyX2S

Public Key:
04d0de0aaeaefad02b8bdc8a01a1b8b11c696bd3d66a2c5f10780d95b7df42645cd85228a6fb29940e858e7e55842ae2bd115d1ed7cc0e82d934e929c97648cb0a

How can I determine the address from the key (without using Electrum)?
I understand that the derivation route is private key -> public key -> address, so I've found a way to generate the public key in Java using BitcoinJ:
BigInteger privkey = new BigInteger("0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D", 16);
byte[] bytes = org.bitcoinj.core.ECKey.publicKeyFromPrivate(privkey, false);
String publickey = new BigInteger(1, bytes).toString(16);
while(publickey.length() < 130){
    publickey = "0" + publickey;
}
Log.d("public",publickey);

It gives the correct public key as shown above, so I just need to find a way to get the address.
I don't know much about different address formats, but my goal is to use the address to check the balance using some public API like blockchain.com. I guess this is the P2PKH-type address.
I tried this:
NetworkParameters params = MainNetParams.get();
ECKey key = ECKey.fromPrivate(privkey);
String address = LegacyAddress.fromKey(params, key).toString();
Log.d("address",address);

Which gives me this address:
1LoVGDgRs9hTfTNJNuXKSpywcbdvwRXpmK

But the address is different.


texts: Add an Address with Label to Send Coins Address Book via a RPC call

texts:
Doing some ecommerce stuff

Im not a c++ guy..I know in C# this is all doable

Does the client support or could it support a RPC call on an open port to add an Address & label pair with an Amount

i.e ComputerWorld Order (5 x 7970) Order# 3340 100.5 BTC

You could have an Do you want to allow confirmation yes/No

This would then allow a 1 step process for users top purchase goods online instead of copy paste etc


texts: Can I use my wallet on different computers?

texts: I'm used to synchronize my data on different machines. Depending on the data I use SVN, Dropbox or SSH (Unison). Is this possible with the bitcoin wallet, too?


texts: Is it possible to avoid a ~$40 fee for a 220-input transaction?

texts:
I want to transfer all my BTC from my old Electrum wallet to a new one, so that I can claim Bcash using Electron Cash without risking losing my BTC. The problem is that my ~0.143 BTC came from hundreds of transactions (cloud mining, faucets, etc.) and even with the lowest fee on the Electrum slider (confirmed within 25 blocks), the total fee is 0.013 BTC!

Is there any way I can avoid such a huge fee, while ensuring that my money is sent. There is a 'replaceable' fee option in Electrum. Does that mean that I could try to set the fee/kB very low and up it if nothing happens, without risking my BTC getting lost?

UPDATE: I sent a transaction off with replaceable fees at ~8 satoshi/byte, thinking that there was nothing to lose. It was confirmed in less than an hour :-)


texts: Strange re-connection problem with python-bitcoinrpc

texts:
I am using https://github.com/jgarzik/python-bitcoinrpc to access the bitcoin core rpc. I have found a very strange re-connection problem.

from bitcoinrpc.authproxy import AuthServiceProxy, JSONRPCException

# rpc_user and rpc_password are set in the bitcoin.conf file
1. rpc_connection = AuthServiceProxy("http://%s:%s@127.0.0.1:8332"%(rpc_user, rpc_password))
2. best_block_hash = rpc_connection.getbestblockhash()
3. print(rpc_connection.getblock(best_block_hash))

The above code runs well in the python interactive window. However, after a while (for instance 10s), when I run the line2 again, it crashs with following info:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/fangjun/.local/lib/python3.5/site-packages/bitcoinrpc/authproxy.py", line 136, in __call__
    'Content-type': 'application/json'})
  File "/usr/lib/python3.5/http/client.py", line 1106, in request
    self._send_request(method, url, body, headers)
  File "/usr/lib/python3.5/http/client.py", line 1151, in _send_request
    self.endheaders(body)
  File "/usr/lib/python3.5/http/client.py", line 1102, in endheaders
    self._send_output(message_body)
  File "/usr/lib/python3.5/http/client.py", line 936, in _send_output
    self.send(message_body)
  File "/usr/lib/python3.5/http/client.py", line 908, in send
    self.sock.sendall(data)
BrokenPipeError: [Errno 32] Broken pipe

if I reconnect the server again by running line1, then line2 runs well.

It seems I need to run line1 from time to time, but it doesn't make sense. Can some tell me the reason? Thanks.


texts: Java bitcoinj: ECKey hashCode() and equals() overrides inconsistent

texts:
In my recent endeavor to learn Scala, reading the Scala book by Martin Odersky et al. I remember being struck by the emphasis placed by the authors on the difficulty of properly overriding the equals and hashCode methods of our user-defined types. In particular, I remember that failing to define equals and hashCode consistently may lead to subtle bugs in code which handle hash-maps and dictionaries. Now the ECKey class of bitcoinj seems to suffer from such inconsistency. I was wondering if anyone knew the background to this, whether this is an oversight or a deliberate choice, or if there is a fundamental reason why equality between keys should take creation time into account (for example) while hashCode should ignore it. Am I being pedantic or should equals and hashCode be consistent?

import org.bitcoinj.core.ECKey;

public class Test {

  public static void main(String[] args){

  // random compressed key
  ECKey k1 = new ECKey();

  // same key, but creation time is different
  ECKey k2 = ECKey.fromPrivate(k1.getPrivKey());

  // The two keys are deemed different, due to creation time
  System.out.println(k1.equals(k2));  // false

  // yet hashCode ignores time of creation
  System.out.println(k1.hashCode() == k2.hashCode()); // true

  }
}


texts: Bitcoin RPC RegTest not validating addresses

texts:
I am attempting to use Bitcoin RPC in regtest mode, however, when I try to validate a bitcoin address with the following function

public function validateAddress($address)
{
    $command = new \Nbobtc\Command\Command('validateaddress', [$address]);
    $response = $this->client->sendCommand($command);
    $contents = $response->getBody()->getContents();

    return $contents;
}

it returns...

Array ( [result] => Array ( [isvalid] => ) [error] => [id] => )

Any ideas why the isvalid value is missing?

I could have sworn this was working a day or two ago...


texts: Sending funds from a Segwit address to a non segwit

texts: I just generated a Electrum wallet with the Segwit option on. I wonder what happens if I try to transfer SegWit -> Non-SegWit or Non-SegWit -> SegWit: Will the funds be confirmed and get transfered or will it be lost forever?


texts: What is the reasoning behind the choice of 2^256-2^32-977 for the prime on the secp256k1 curve?

texts:
In Bitcoin's elliptic curve (secp256k1),

the prime

p = 2^256 - 2^32 - 2^9 -2^8 - 2^7 - 2^6 - 2^4 - 1

the generator point

Gx =
0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798

Gy =
0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8

and the order of the group generated by G

n = 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141

are predefined.

What is the reasoning behind this? Why are these values more secure or efficient than any other ones?


texts: alone in a CoinJoin amongst colluding scoundrels- can they spot you?

texts:
What if you participate in a CoinJoin and all the other actors that you're exchanging with are colluding against you, or controlled by the same person.

I guess in this scenario if they wanted they could easily identify you, isn't that right?


texts: What is happening when a channel is pending?

texts: What is happening when a channel is pending when opened? How long does it usually take? To open a channel with a node you're already connected to you don't need to get consensus from all the other connected nodes (as you would if you were sending a transaction on chain) so why the wait?


texts:
In discussions on the intrinsic value of BTC, one often reads the claim that BTC is scarce because the maximum amount of BTC that can ever exist is 21 million BTC. I find this explanation rather unsatisfactory.
If a group of people collectively decide to move all their savings into tulips, the price of tulips should skyrocket. However, new greenhouses could be built and some farmers could start growing tulips. As a result, the price of tulips would start falling and converging to the price prior to the "tulip mania". Seeing the value of their savings dropping, these disappointed tulip-lovers would rush to sell their tulips, causing the price of tulips to plummet. The media would then mock them for their financial illiteracy. It's hard out there for a tulip-lover...
If the former tulip-lovers then decided to move their savings into gold, the price of gold would almost certainly rise suddenly. However, new gold reserves cannot be manufactured out of, say, lead — assuming that no form of working alchemy is developed, of course. Without the required increase in the supply of gold, the price of gold would stay "inflated" and there would be no panic-selling. A computer scientist would perhaps say that the supply of gold is rate-limited.
I know nothing about economics, but I suppose an economist would say something along the lines of "the supply of gold is much, much more price-inelastic than the supply of tulips". To me, BTC looks closer to digital gold than to digital tulips.
Questions — As a total novice, the scarcity pertaining to BTC I do see is in the rate at which new BTC can be generated. But, what exactly does that have to do with the number 21 million?  When mentioning the total amount of Bitcoin that can ever be mined, shouldn't the practical upper bound on annual mining also be mentioned? Is my understanding of "Bitcoinomics" roughly accurate?


texts:
I need single integer converted from public BTC address. Is it enough to Base58Check decode the address and I will get hex/binary format of that integer or do I need to do something more?
What will be the format of Base58Check decoded data? Will there be any checksums, additional bytes?
I can write a script in Bash/Perl/Python if I would have instructions.


texts: How to run a python script when occur incoming transaction in Bitcoin core 0.18?

texts:
I want to run a python script when occur an incoming transaction. I think set zapwallettxes flag in bitcoin.conf but I don't know where set the script path to execute.

Is it possible to execute another executable file or another language script?


texts: Unconfirmed Transaction (after two days)

texts:
Okay, so I have done research on this. My problem is that my fee was embarassingly low. Ive always had my wallet do it automatically and I switched wallets and it was set at .0005 BTC/kb (I didnt check until after a day of no confirmations). Is there any way someone could help me get this transaction confirmed (fee is a whopping 32 cents). Now that I understand how this works, I have set my wallet to manual fee per transaction where I will do $20-30 per transaction for now on. This is extremely embarassing and I meant no disrespect to the miners or the community

https://blockchain.info/tx/c326f5652d7b36a0fb593874714a69b67db3fc810e34b73e0b6eecb087508fb9


texts: I have written a simple program that determines the available balance of a Bitcoin wallet, but it used the public API for QBitNinja at http://tapi.qbit.ninja, and everything is working fine, but I wish to run the QBitNinja server locally on my PC. I have Bitcoin-QT / bitcoind installed and fully updated with the latest blockchain data, NBitcoin installed in my project, as well as the QBitNinja client libraries. However, try as I may, I cannot seem to figure out the steps needed to get the QBitNinja server running locally, connecting to bitcoind / Bitcoin-QT. Any assistance would be greatly appreciated. I am running Windows 10 Pro, and IIS Server that comes with Windows 10.


texts: Buying a Gridseed Mini ASIC Miner -Beginner

texts:
I'm new to the field of cryptocurrencies.It seems that without good hardware i cannot earn anything.As a starter - is  Gridseed Mini ASIC Miner a good choice to buy http://www.makeuseof.com/tag/gridseed-mini-asic-miner-review-and-giveaway/

Will it cost too much electricity? Can i make something out of it?

Please advice


texts: Why the signature is always 65 (1+32+32) bytes long?

texts:
A signature created by the Bitcoin-Qt client can always be decoded (base64) to a 65-byte array. This array seems (according to https://github.com/bitcoin/bitcoin/blob/master/src/key.cpp#L217) to contain a header byte, a 32-byte R part, and a 32-byte S part.

I've extracted some (R,S) pairs from some ECDSA Signatures encoded in the DER format. I found that R and S are not necessarily of 32 bytes in size. They sometimes can be 33 bytes long. Could anyone tell me why the signature created by the Qt client is always 65 bytes, or whether it is OK to always convert both R and S into a 32-byte array? Thanks.


texts:
There seems to be a new SatoshiDice clone called BetCoinDice.

Everything is the same, except the expected return for the player is higher since the house percent is lower.

If this is the case, is it true that it doesn't make sense to use SatoshiDice any more?


texts: What happens when bitcoin loans start to appear?

texts:
What happens when bitcoins loans start to appear?

Loans have interest rates that "create additional value". Given the limited amount of bitcoins, couldn't we realistically run out of them?

BitBanker loans 1000BTC to the user with a 5% interest. The loan could be backed up with, say, a house.

The user then has to pay back 1050BTC, somehow acquiring the 50BTC deficit.

Given how quickly interest on top of interest grows, won't the bankers get to 21 million BTC quite quickly?


texts: What percent of recently mined coins being actively traded vs saved?

texts:
I'm trying to understand the recent increase in BTC value in relation to mining.  I am trying to answer the question

Are miners (with powerful ASIC hardware) saving the BTC, and not selling them, thereby reducing supply?
Has the demand increased beyond what has been mined?


texts: Can I find out on which website I got my Litoshi address?

texts:
I can't remember where I got my Litoshi address. Is there a way I can find it because boxlit transferred my litoshis already?

I saw the transaction through block.io. I don't think I got it there (block.io). I did not write it down because I always save my username and password in websites I register and sign, but the problem is, I can't remember what website.


texts: Who checks if the entire chain in valid?

texts:
How can we be sure that the entire chain is valid?

1- I read somewhere that one of the purposes of blockchain is that you can't change the blocks of the past without recomputing the entire thing. Is that assumption correct?

So if you could hypothetically recompute everything, you could generate a new chain. I also read somewhere about some problems that Proof of Work try to solve and there was this possibility of a concurrent plausible solid chain.  How is that possible? Who can generate an entire chain?

I explain my doubt:

2- Miner will find a nonce, giving a block data, to generate a hash that matches a certain difficulty. Is that correct?

So the miner knows a new block. But not the entire chain. 3- Does it? So when it finds the nonce and hash it announces a new block to a different kind of node, let's say the full node (what is that exactly?).

4- Where in the flow and by whom in the network the entire chain will be exchanged so they need to decide which chain is better?

5- By the way, what is the best chain given two versions of them?

extra:
6- ok, the blocks are correct and the chain is valid everybody agrees with that. Who in the network checked if A that passed 1btc to B had 1btc to perform this action?

Please could you clarify 1, 2, 3, 4, 5 and 6?


texts: As I heard the Bitcoin bubble started around April 2011 due to an article on Bitcoin in some news website. What article started the Bitcoin bubble?


texts: Cryptocurrency exchange needs more info than any bank or brokerage firm?

texts:
I wanted to quickly sign up for a cryptocurrency exchange today to act on some info I found out about a low-cost coin (hahahah, quickly. how naïve).  In signing up for the account, I got to a step asking me for my SSN, which is pretty normal. But then it asked for high resolution photos of a picture ID AND a proof of residency document??

I have MULTIPLE online bank accounts and brokerage accounts, with tens of thousand of dollars being held and traded in various forms, and I've never had to provide such information. Why the heck is the supposedly "anonymous decentralized currency of the future" requiring me to send in my firstborn and the results of my latest colonoscopy??


texts: A different way to create coinbase transaction

texts:
AFAIK when a miner succeeds in creating a block, he puts a special transaction (coinbase) in it which spends no input and sends a fixed amount of BTC to an address he can arbitrarily specify.

Instead of doing so, can we do the following: Miner simply puts an address in the block header. When he succeeds in creating the block, all nodes that receive this block create the coinbase transaction -which spends no input and sends the fixed amount to the address in header- in their UTXO pool.

Would that work?


texts: What restrictions will be placed on X509 certificates that are used in the payment protocol?

texts:
I'm looking at BIP0070 and also this forum thread which is locked for some reason; so I'll post here.

When it comes to validating a certificate for the purpose of a Bitcoin payment, each certificate is "authoritative" for different things, such as SSL or S/MIME.  Some certificates also have something called a "Basic Constraints" set so an end entity isn't marked as a CA... thus confusing the CA validation framework Bitcoin is using.

Question

What are the Extended Certificate rights that are required for use with Bitcoin?  I would assume something with "server authentication" allows for "domain.com" payments, versus a valid email which is "user@domain.com" for SMIME.
Does the breadth of certificate validation types allow for unnecessary spoofing?
Is there going to be a visual distinction for different certificates (Those with "all purposes", are expired, for Server Auth, or email?)
Finally, can there be a requirement for DNSSec validation when communicating with a server?
Edit: Will certificates be validated in a "normal" manner such as validating the Basic Constraints?  (I'm pretty sure OpenSSL will do this for you in a platform consistent way)


texts: How can I find out if an e-wallet service uses a fractional reserve system?

texts:
A comment on this answer pointed out that the total amount of bitcoins in circulation could appear to go above the limit of 21m if wallet services use a fractional reserve system. However, in that scenario you actually no longer have bitcoins - instead, you have some kind of bitcoin-credits that rely on a specific 3rd party to be used.

If my understanding is correct, it should be possible to determine through the blockchain whether a given e-wallet service:

Definitely isn't using fractional reserves for a given account, or
Might be using fractional reserves

How would this be done? Has anyone summarised this information for a selection of e-wallet services?


texts: Is there a one-stop shop to introduce businesses to accepting Bitcoin?

texts:
I'd like to promote Bitcoin in my neighborhood, but I'd also like to do it efficiently... So I'm trying to figure out where and how to direct business owners into a simple A-B-C set of steps that explains everything from the hardware / software to the tax implications / software needed.

I know there exist lists of tools businesses could use, but those lists often seem overwhelming. Any ideas would be appreciated!


texts: How to read each bitcoin block by python

texts:
I need to read all Bitcoin transactions from the first one until now and extract all Bitcoin addresses for further analyses

Any idea how to do it in Python?


texts: Transparent Crypto Bitcoin 2.0 Technologies vs Anonymous Bitcoin Crypto 2.0 technologies?

texts:
I'm still doing more research on Crypto 2.0 or Bitcoin 2.0 technologies and still weighing the pros and cons of each. So far we have the following technologies that are either backed by a company or a few people:

Ethereum
Counterparty
Bitshares
Ripple
Coin Prism
Sidechain

And then we have anonymous Bitcoin 2.0 crypto like NXT that took after the steps of satoshi of staying anonymous.

What I want to find out is how does being transparency play into these systems. I can understand that being transparent gives the ability to hold these companies or people accountable if anything goes wrong. But this also gives these entities the ability to be manipulated by government and laws that govern what they can and cannot do. One case is with counterparty, as they had a gambling tab within their system which they had to limit via Geo IP location due to US laws as they don't want to be labeled as a facilitator of a gambling site.

Can someone provide a list of PROS + CONS on each side of the coin for being a transparent 2.0 technology to being a anonymous 2.0 technology.


texts:
A few people I know compare bitcoin and gold regarding currencies with integrity; Martin Armstrong on Zero Hedge compared both in a recent post.  One advantage I currently see that bitcoin has over gold is the cost to verify is much lower; it costs more to make sure that I've received legitimate gold than it does to verify that I've received a legitimate bitcoin.  But this depends on the cryptography always being legitimate - what if in the future someone cracks it?

What would happen if someone in the future is able to crack bitcoin's cryptography?  Does the system adapt at this point (and can it?)?


texts: How to list non-HD addresses in bitcoin core?

texts: Let's say I imported some private keys, how do I distinguish between those and addresses generated from the HD master key?


texts: What the difference between old segwit (3) and new segwit address (bc)?

texts:
i'm not that kind of person who understands cryptography and math, can you tell me simply the main purpose of new segwit address? are transactions fee the same for new segwit (bc1)?

instead of "Old Segwit" and "New Segwit" what would you call em?


texts: Cannot get Bitcoin-QT to run in testnet mode

texts:
I downloaded Bitcoin-QT for Windows 7 into:

MYUSERNAME/Downloads/bitcoin-0.8.6-win32/bitcoin-0.8.6-win32

I want to run Bitcoin in testnet mode, so I created bitcoin.conf with only the following content:

testnet=1

I put copies of bitcoin.conf into the following folders:

MYUSERNAME/Downloads/bitcoin-0.8.6-win32/bitcoin-0.8.6-win32
User/MYUSERNAME/AppData/Roaming/Bitcoin

When I double clicked on the Bitcoin-QT icon to execute the following, Bitcoin-QT starts up but it does not appear to be in testnet mode.

MYUSERNAME/Downloads/bitcoin-0.8.6-win32/bitcoin-0.8.6-win32/bitcoin-qt.exe

Can anyone tell me why it does not seem to go into testnet mode?

I went to Start > cmd to get the DOS prompt.  I entered the following and it worked:

C:\User\MYUSERNAME\Downloads\bitcoin-0.8.-win32\bitcoin-0.8.6-win32>bitcoin-qt.exe -testnet

But going into DOS prompt to start up bitcoin-qt is a hassle.  It would be easier if I can just double click on the Bitcoin-QT icon.


texts: How can I withdraw Litecoin from a paperwallet?

texts:
How can I withdraw my Litecoin from a paperwallet?

I have tried to use blockchain.info but it seems like it is only bitcoin that I can withdraw with that.

I used the bitcoinpaperwallet.com webpage to make the wallet.

Thanks guys!


texts: Does Taproot allow CoinJoin-style transactions without revealing all signers?

texts: Taproot allows to hide a script behind a transaction and only release the relevant information when the output is being spent. Would this allow for a construction of a script with N participants + initiator to generate a script where all N participants have to sign it and the initiator finally signs? Would the MAST reveal all other signers or just the initiator who finally signs the script and can proof that he followed its rules?


texts: Bitcoinj How to create multi-signature address using bitcoinj

texts: Can somebody help me with step-by-step list of how to create a multi signature 2-of-3 transaction using bitcoinj api?


texts: What happens if segregated witness never reaches the 95% adoption threshold from miners? Will it still take effect for those transactions where the miners have adopted it?


texts: Why DARPA wants blockchain based secure messaging system

texts:
DARPA (US Defense Advanced Research Projects Agency) has released a Request for Proposal for a Secure Messaging Platform using a blockchain framework.

The following is the Objective paragraph from DARPA's call for proposal:

  OBJECTIVE: Create a secure messaging and transaction platform that separates the message creation, from the transfer (transport) and reception of the message using a decentralized messaging backbone to allow anyone anywhere the ability to send a secure message or conduct other transactions across multiple channels traceable in a decentralized ledger.

The request for proposal is available in full, here:
DARPA Call for Proposal for Secure Messaging Platform.

Why are contemporary secure messaging platforms like TextSecure, Cryptocat, XMPP/OTR, Bitmessaging and so many more NOT enough?

What do these contemporary solutions lack, as the Secure Messaging Scorecard suggests many applications have all these features?

What does blockchain provide when it comes to Secure Messaging and why it is necessary?

How can Military Interdepartmental Purchase Requests (MIPR) be implmented using the secure ledger or blockchain?

In particular, this paragraph of the proposal is not making sense to me

The messaging platform would act as the transport for a cyptographically sound record of all transactions whether they be MIPRs, contracts, troop movements or intelligence. Troops on the ground in denied communications environments would have a way to securely communicate back to HQ and DoD back office executives could rest assured that their logistics system is efficient, timely and safe from hackers. The benefits are broad and could even be applied to domains such as space. With crowded skies it’s important to maintain situational awareness of all satellites and those concerned with space situational awareness/telemetry or air traffic control could instantly share data between nations using a separate but equivalent ledger implementation thus removing questions as to the authenticity and integrity of the data.

What does transport mean here?
How does blockchain help troops communicate in denied communication environment help?
I am also not clear about the argument on situational awareness of satellites and how does blockchain enable sharing data between nations.

Simple answers would really help me and others like me. Thanks


texts: how to generate or calculate a key pair from a seed?

texts: Using, for example, the electrum wallet, how, exactly, is the key pair, and hash address, generated from a paper or metal wallet?  Assuming libsecp256k1 was employed.


texts: Transfer to Bitcoin ABC wallet is waiting for full download

texts: I'm fairly new to cryptocurrency and decided to transfer some of my LTC to BCC using a Bitcoin ABC wallet on my MacBook. To test the wallet I already transfered 1 BCC to the generated adres. I was not aware that this wallet had to download the whole blockchain before I could use the wallet. Now I'm unable to reach this one BCC... Is there any way around downloading the whole blockchain to my MacBook? I'm at 2% increase per hour, around two days waiting for me??


texts: Running multiple Bitcoin nodes on same network

texts:
I want to run a bitcoin node on two separate devices (computer + dedicated hardware device) on the same network (and would like them to be externally accessible).  Specifically, I have a Casa Node with bitcoind, and I have a Mac with bitcoind. Both on my home network.

I've read it is critical that you forward port 8333 on your router to the IP address of the computer that is running your node, so I'm not sure what to do on the dedicated hardware device then.

I've seen you can add port and rpcport arguments to the bitcoin.conf file, but I'm can't figure out exactly how this setup will work on the same network with two different bitcoin nodes.

Any help by someone more expert (most people likely ha) than me would be appreciated, thanks!

Bitcoin.conf file

daemon=1
server=1
prune=750
zmqpubrawblock=tcp://127.0.0.1:28332
zmqpubrawtx=tcp://127.0.0.1:28333
rpcuser=xxx
rpcpassword=xxx


texts: Are my BTC now BCH?! What happened?! Is my money lost?

texts:
i don't know if i made a big mistake. I start from the beginning:

I wanted to transfer my BTC (worth 350$) to kraken. Accidently i sent them to a BCH address. You can see it here:
https://blockchain.info/tx/45c843c767b5ff8543adacb900c13fc03289639216c9de0862cb5ee8b41a863b
It got enough confirmations and so I wrote the kraken support whether they could help me to get my btc back. but then i realized that blockchain.info now showed that i would have the amount i sent to kraken now as BCH which was of course much less (50$) . I couldn't find out on which address i got the money because blockchain.info wasn't able to show on which address i got the money, it only showed that i have 50$ in total as BCH.
I read about how to get my money back to BTC, so I transfered my money to my wallet in EXODUS as BCH (blockchain.info only offered this transfer method) to a BCH address. It again got confirmations:
https://blockdozer.com/insight/tx/63be7ff8d38e648c19a1d0a9dc66a87ee64ae1359888ac8404b017d82c607dc4
I now have the 50$ on my BCH address in exodus, but this tool wasn't able to get my money back to BTC. I used this tutorial:
http://support.exodus.io/article/189-ive-sent-bitcoin-cash-to-my-bitcoin-address

is it possible to get the money back to BTC or is my money now forever BCH? Please help me. The one to help me get my money in BTC back, gets a little donation.


texts: How do you update safely to 0.6 the working C-Lightning node?


texts:
I did a transaction 4days ago with low fee that was about 0.2 USD and it has been not confirmed yet.
I just wanna know how i can cancel it ?
Or how many days it takes to this transaction to be confirmed.
Would you please help me through


texts: What is the behavior of the try catch statement in lines 1707-1729 in the ui.cpp in the release 0.1?

texts:
In the first public release, ui.cpp has this code on the lines in the subject:

void CSendingDialog::OnReply3(CDataStream& vRecv)
{
    int nRet;
    try
    {
        vRecv >> nRet;
        if (nRet > 0)
        {
            Error("The payment was sent, but the recipient was
                unable to verify it.\n"
                "The transaction is recorded and will credit to
                the recipient if it is valid,\n"
                "but without comment information.");
        return;
        }
    }
    catch (...)
    {
        //// what do we want to do about this?
        Error("Payment was sent, but an invalid response was received");
        return;
}

The try catch statement at the bottom shows the error as payment sent but invalid response was received. In this case, does this mean that the send BTC would be lost forever as in this question or does this mean that the transaction would be part of some orphaned block (like here).

Bonus, was something done to address the comment in the code?


texts:
I have 2 BTC in my Bitstamp wallet.
I have over 10,000 XRP (no issue with reserve)

I have trusted Bitstamp up to $300 in my Ripple client.

I've tried to enter an order selling 1 BTC for 8400 XRP.

  Transaction failed!

  Error: Insufficient balance to fund created offer.

Is there a BTC wallet in my Ripple account where my BTC need to be?  Your help is appreciated.


texts: Someone scammed me, and I want my money back. What can I do?

texts:
I was cheated by ebankbtc.com, which gave me this address: 1QiCsWaZxvNy4hXZMvQJEBcnVm5KH3fK5

You can see the transaction here:
https://blockchain.info/tx/e22206dcf27249afa6576443b3953b11ae43c04050c9e663a64f61ea320a7a4f

So, I lost my own Bitcoin.

What can I do about it?


texts:
I'm new in the bitcoin field and I need to understand about transactions.
When Bob is sending bitcoins to Alice, Bob will create a tx, he will add Alice's address, sign it and broadcast it in the network. But what is the previous transaction in this case? Is it a different tx from the one between Bob and Alice?


texts: How a new wallet knows balances locked in P2SH transactions?

texts: If my old wallet created and submitted a P2SH TX to the blockchain, and I migrate to a completely different wallet, how can the new wallet detect that that UTXO belongs to me? Since the script is hashed, it can be anything and contain unpredictable information, like other PKHs in multisig transactions


texts: What OpenCart plugins are available or in the works for Bitcoin transactions?

texts: I've installed the walletbit module in my installation of OpenCart but any others would be appreciated, especially if someone's working on MTGox/Tradehill integration! Is there much in the works or anything I've missed?


texts: Bitcoin Module - Hash512-EVP_ByteToToken

texts:
Is there any standalone software modules created which allow the user to complete the following:
     1. Enter in passphrase
     2. Enter a given salt
     3. Enter the number of rounds

I am looking for this in order to find the value, and locate the memory location in either Bitcoin src code or Wallet.dat file database. I have found the master key, iv, salt and rounds in wallet.dat file already. Thanks for all the help and I will pass tips to those who point me in the right direction. Thanks again.


texts:
I'm new to mining, and using GUI miner on windows 7 AMD APU A-Series. I set it up today, put in my username.workername and put in stratum.bitcoin.cz as the host, and 3333 as the port. It says I'm getting 2 MHash/sec, but when I go to the Slush's pool website it says my worker is offline!

Can somebody please tell me what I'm doing wrong?


texts: Could the EC2 infrastructure be used to efficiently launch a 51% attack?

texts:
This excellent answer from Serith states that one would need 31150 ATI 5870 graphics cards to launch a 51% attack. Amazon EC2 offers computers for rent for 2.10$ per hour. These instances have 2 x NVIDIA Tesla “Fermi” M2050 GPUs. Given that these are as fast as the ATI 5870 (I have absolutely no idea whether this is the case), and that Amazon has enough of these instances available, one should be able to launch a 51% attack for one hour for a mere 65415$. If the hash rate of the Bitcoin network varies over the time of the day or under such events as a power cut, then it could be cheaper.

Is this a potential threat to the Bitcoin network?


texts: Is it possible to combine PoW with PoS by taking turns?

texts:
I have read about cryptocurrencies and am very excited by many. I have read that one of the worries and constant debates is Proof of Work vs Proof of State with respect to securing the validity of the blockchain, especially within Ethereum.

I wondered why we would not just combine the two. For example, the first block validated by PoW, second block by PoS, third by PoW, etc. As each block depends on the previous a 51% attack would be a lot more difficult and power consumption significantly reduced.

Is there an obvious problem with doing that?


texts: Unable to get private key for Blockchain wallet

texts: I am new to BTC and I have a question: How to get private key from Blockchain wallet for a "Watch only" address? I have been trying for days with no positive results. Thanks.


texts: Where can you see current Bitcoin miners signalling SegWit2x?

texts: Hi I know you can view current miners signalling 'intent' to implement SegWit2x on coindance https://coin.dance/blocks . But is there a live website that show miners actually signalling SegWit2x?


texts: I had to move around wallets and so on, and when I re-installed Knots (yeah I'm that edgy), it doesn't find the transactions to my segwit addresses. I can probably find the SW addresses somewhere, but probably not the regular ones I used addwitnessaddress with. Is this solvable?


texts: Bitcoin RPC - settxfee specific amount rather than based off transaction size?

texts:
How am I able to use the "sendfrom" command with a specific amount of 0.0005 BTC as fees no matter how small or big the transaction is in bytes?

settxfee is based off fees per bytes.


texts: What would be the easiest way to make my bitcoins into real us money?

texts: I have zero knowledge on this subject, I did not buy into bitcoins I only played poker on a website that provided them for free and ended up gathering some bitcoins. What is the difference between different websites that allow you to convert them to us currency, what is the most safest way to do this? I need all the details.


texts: bitcoind does not issue expected "rpcuser" message after installation

texts:
The instructions for installing the non-ubuntu linux bitcoind read as follows:

Before using the Bitcoin Core daemon, bitcoind, you need to create its configuration file with a user name and password. First create the .bitcoin directory, create (touch) the file, and set the file’s permissions so that only your user account can read it. From your terminal or console, type:

mkdir ~/.bitcoin
touch ~/.bitcoin/bitcoin.conf
chmod 600 ~/.bitcoin/bitcoin.conf

Then you can run the command bitcoind. It will print output similar to this:

bitcoind
Error: To use the "-server" option, you must set a rpcpassword in the configuration file:
/home/bitcoinorg/.bitcoin/bitcoin.conf
It is recommended you use the following random password:
rpcuser=bitcoinrpc
rpcpassword=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
(you do not need to remember this password)
The username and password MUST NOT be the same.
If the file does not exist, create it with owner-readable-only file permissions.
It is also recommended to set alertnotify so you are notified of problems;
for example: alertnotify=echo %s | mail -s "Bitcoin Alert" admin@foo.com

I did this, but it does not return the expected message. Instead the software just hangs and does not appear to be doing anything at all. What should I do?


texts: Altcoins: Determine how many confirmations to require to deposit

texts:
For Bitcoin it is common knowledge that 6 confirmations suffices. For the hundred of Alt Coins however, I'm not sure what the best practise to be protected enough from double-spents and the likes is.

I saw Bter.com requires different confirmations varying on which Altcoin you want to deposit.

For example COMM-coin requires 10 confirmations, but BBQ coin 6, and Infinitecoin only 4.

Is there a mathematical method behind this? How do they know how many confirmations to require?


texts: Destination Tag of Ripple Desktop Wallet

texts: I want to withdraw some xrp from an exchange and deposit to my Ripple desktop wallet. I know the address to deposit, but what is the destination tag? The exchange does not let the destination tag to be empty? What should I enter in this field?


texts: MintChip and Bitcoin - how do they compare?

texts: The Royal Canadian Mint announced some time ago a new solution called MintChip, which appears to share some similarities to Bitcoin. How do those two projects differ, and how are they similar?


texts: partial signature (of P2SH) in Bitcore. howto?

texts:
Using pybitcointools, it is easy get partial signatures of a p2sh using the multisign function. Then, these can be communicated around to the several controllers of the p2sh address.

Using bitcore, I can sign a p2sh (using ... .sign(privkey)) but I do not manage to get a partial signature object, separate of the transaction itself, which I could send to other owners of the p2sh address (who could be using pybitcointools for instance).

How do you go about getting partial signatures of p2sh in bitcore please?
(What am I getting wrong?)

Thanks


texts: How many Dogecoin-satoshis will ever exist?

texts:
In Bitcoin, there will only ever be ~21,000,000 coins (slightly less, technically, but I'll just use 21 million for easy calculation). Each bitcoin is 10^8 satoshis. This means there be a maximum:

2,100,000,000,000,000 satoshis

What is the equivalent number for Dogecoin?
Is it larger than the maximum 64 bit unsigned integer?


texts: Why does the threshold apply to the MUST_SIGNAL phase in revised BIP 8 (lot=true)? Why doesn't it enforce 100 percent signaling?

texts:
BIP 8 states that:

During the MUST_SIGNAL phase, if (2016 - threshold) blocks in the
retarget period have already failed to signal, any further blocks that
fail to signal are invalid.

Why doesn't it enforce 100 percent signaling during the MUST_SIGNAL phase rather than merely the threshold?


texts: How to get the derived public key from xpub?

texts:
Here I'd like to generate the other address use xpub.

Is there any library (python) could help to derive the new address from extended key?

such as:

gen_new_pub(xpub, new_path) to get the derived public key.

Of course, the library supposes could support

gen_new_prv(xprv, new_path) to generate the corresponding private key according to the xprv and path.


texts: Threat probability? 1 state controls >70% of miners. Other states go to war with them

texts:
This is almost certainly a silly question, but there are a lot of new bitcoin owners like me and a specific threat was made today which sounds credible to those of us who lack deep knowledge of bitcoin.
The specific threat is this one:
1: China controls 70% of the miners. SOURCE
2: They are using Hydroelectric and Nuclear Power reactors to do this. SOURCE
3: The United States (and allies) are seeking to destroy bitcoin in a war with China.
4: Bitcoin will go to 0 and US regulated coins will survive. SOURCE
So it's kind of 2 threats rolled into 1 and I'm trying to come up with a "probability of threat number" to determine if I should even devote time to considering this.
My guess is that the probability is less than 1% but it's just a guess and I have a high amount of uncertainty due to my current depth of knowledge.
Again, please forgive the silliness of the question, but any assistance to help improve my confidence that the threat is not to be taken seriously would be appreciated.


texts: Why bother having limitations on Bitcoin Coinbase Transaction Scriptsigs?

texts:
There are a few limitations on the structure of the coinbase (reward) transaction in a block.

There is only one input. vin.size() == 1 (source)
It doesn't reference any previous output. vin[0].prevout.IsNull() (source)
The scriptSig is not too big. vin[0].scriptSig.size() <= 100 (source)
The scriptSig is not too small. vin[0].scriptSig.size() >= 2 (source)

I don't see the point of any of these. #1 and #2 enable BIP34, but they are not necessary to achieve the same outcome. The size constraints don't really limit anything, if a miner wants to make a large block they can just many many outputs in their coinbase, or many many transactions into their block.

Why isn't a coinbase transaction just a transaction which:

Has at least one input that doesn't reference any previous outputs (for use in BIP34)
Allowed to claim up to (block reward + fees) more than it can spend

In particular, the coinbase could optionally have further null inputs and could spend previous outputs.

I know for Bitcoin it's likely too late for these to change. Is this a case of over-designing, or are there security reasons for any of these constraints on the coinbase? Loosening constraint #2, in particular, makes me pause because of a bitcoin development mailing list email concerning how allowing the coinbase to spend prevouts would enable securely paying a miner to mine a chain reorganization in a particular way.


texts: Is there any standardized way to define HD wallet accounts used to participate in multi-signature transactions? How do existing multisig wallets derive their keys from the seed it? How is Bitcoin Core doing it, as it has added support for both, HD wallets and PSBTs, recently?


texts: How do I read the contents of wallet.dat in C#

texts: I'd like to be able to add, remove, export etc. keypairs from my wallet.dat file. Looking over the source code of pywallet it doesn't look like such a tough task, but of course it's not as simple as from bsddb.db import * in C# and Google is failing me. Does anyone have some sample code or resources for how to handle wallet.dat in C#?


texts:
I need to query blockchain.info with an address and determine how much is there, ignoring transactions that don't have 3 confirmations.

Can anyone give me a hint how to do this?


texts: How much memory and bandwidth does bitcoind take up on a CentOS Linux system?

texts: I'm thinking about installing bitcoind on my web server that runs on CentOS. How much memory and bandwidth might it take up and would it affect my other sites on my server?


texts: Just bought some Bitcoin for the first time. Then I tried to transfer some of my purchase from Coinbase to my Blockchain wallet. The sent Bitcoin is pending; Blockchain isn't letting me confirm the transaction. Did I do something wrong? Is there a way to cancel the payment? Thanks!


texts: What RBF policy will be default on SegWit v1 nodes?

texts: What RBF node policy will be applied by default in order for a SegWit v1 transaction to relay when encountered. Full RBF, or Opt-in RBF?


texts:
So I imported a watch-only copy of my wallet on the online version of Armory but my balance in the wallet is missing all the amounts I previously received as change. The transaction history clearly shows that a certain amount of BTC were sent back to the same wallet as change but the transaction is grayed out and the amount given as change is not part of my total balance. The change addresses are also not associated with the wallet.

Anyone have any ideas?


texts: Is it safe to delete my bitcoin wallet (coinomi) and restore it from 24 words phrase when ever i need it (once a year)


texts: Validate a payment using bitcoind and json rpc

texts:
I need to implement a BTC payment system on my web-store. But I'm still not sure about the mechanisms I'm supposed to use for payment confirmation.

For example, a user registered on my store and I created a new address for his account by using getnewaddress('user-name').  I also generate a new address for every new transaction. How can I track the status of a payment made to this address?


texts: Parse signature and public key from scriptsig in an input transaction of bitcoin protocol

texts:
I'm interested in bitcoin protocol and checking validation of a transaction.

in a TX message, we can see one or more than one input transaction and every input transaction has a previous transaction and a script.
As you know probably, the script contains two components, a signature and a public key. The public key must match the hash given in the script of the redeemed output. The public key is used to verify the redeemers signature, which is the second component.
I want to parse signature and public key at first step, and in the following I want to check the validation if transaction from public key.
anyone can help me?


texts: Is it possible to restrict where coins from a given P2SH address can be sent to?

texts:
I would like to create a checking/saving style scheme where coins from savings can only go into checking before they go anywhere else.

Is this even possible in Bitcoin?


texts: Creating a tunneling (wormhole) service for bitcoin wallets

texts:
Zcash recently announced a new wallet and service to connect mobile devices to a node running on a private home network using a tunneling service they are calling "wormhole" (1).  Basically it is saying that it is fully end-to-end encrypted and allows the mobile client and desktop instance to bypass complex networking requirements (ex. port forwarding, etc...)

I wanted to see what it would take to set up a similar setup to aid in connecting devices in a secure manner.  This may be more of a networking question, but what would be the best approach to setting up a VPS instance to allow trusted connections between -

bitcoind <-> a wallet
bitcoind <-> lnd
lnd <-> a wallet

Just as a few examples.

My first thought was to create a lightweight client to run on run on the machine running the full node that proxies all of the relevant ports to a chosen IP (the VPS for instance) and encrypts / signs the payload.  The server could basically just receive and broadcast out the requests to the mobile clients who subscribe.

The problem I'm seeing with this approach is it is a lot of custom code for one and the wallet / mobile clients would have to also support decrypting and verifying the message which is unlikely to happen.  The Zcash wallet is able to do this because they of course created the wallet.

Very interested in suggestions on how this could be accomplished (and I will try any suggestions on a fresh VPS so not just asking from a theoretical perspective!)

Ref:

(1) https://github.com/ZcashFoundation/zec-qt-wallet/wiki/Android-App-FAQ


texts:
How do I go about using words I pick in a trezor seed? I only want words that I select and in an order I select.

I'm not worried about this being a less secure way to generate a seed. I will be doing all this off line with a disposable computer if necessary. I want to use a custom word list in conjunction with some custom math that with generate the correct order of my seed.

I have yet to find a way to do this with my trezor. I personally think that my backup seeds are safer in my head then on a piece of paper.

I tried generating public/private keys with a custom mnemonic with custom words. Didn't work.

I tried generating public/private keys with a custom mnemonic with a word list generated from myTrezor.com (A-Z, excluding X, approximately 10 words to choose from per letter)[I did this by typing in each letter and copying the choices from the drop down] Didn't work. [Error: Action was interrupted Invalid mnemonic, are words in correct order?]

Shouldn't a valid public/private key pair be generated regardless of the words I pick and the order I put them in?


texts: I have my 12 word bip39 phrase but not in the right order

texts: I have my 12 word phrase, but when i enter it in a wallet, it brings up an empty wallet, so i think i probably wrote it down in the wrong order. What can i do to recover my wallet?


texts: C++ source code for bitcoin miner software?

texts: Does anyone know where to get the C++ source code of one workable bitcoin miner?


texts: How to transfer bitcoin bought online to my desktop wallet?

texts:
Based on popular recommendations, I have started with Electrum as my Ubuntu desktop wallet and Coinbase as the way to buy bitcoin online.

However, it doesn't seem like there is an easy way to transfer bitcoins from Coinbase to Electrum (not without using a paper wallet).

Is this correct? If I want to conveniently buy bitcoins only, but want to securely store them on my own offline hard drive, what's the best way to do it?


texts: Spending transaction output with only xpriv key

texts: Is it possible to spend a P2WPKH transaction output, with only knowing the xpriv key and not knowing the specific private key that corresponds to the public key of the transaction?


texts: How to convert P2PKH to Hash160 (or something else acceptable by Script)?

texts:
How to convert a bitcoin address (starts with 1) to the right format acceptable by script (I'm using this Ruby library)? I'm doing this:

tx.output do |o|
  o.value(50000)
  o.script { |s| s.recipient('1GzqkR2zNQUzHLpE7PLPjVNJ51FHC3bpDH') }
end

I'm getting:

RuntimeError: Script type must be hash160, pubkey, p2wpkh or multisig

I suspect there is something wrong with the format of the destination address. I cross-posted to GitHub too.


texts: BitCoin Api, Result Keys,BitCoin Protocol documentation

texts:
I am developing android application using https ://blockchain.info/api. i am having problem to understand the Keywords used in result for https: //blockchain.info/address/$bitcoin_address?format=json.

Can any one tell me about the Keys hilighted. I want to show user Transaction history. Any Documentation reference will be helpful. I have also read https://en.bitcoin.it/wiki/Protocol_documentation but it was not help full.

Thanks


texts: How can I recover BCH sent to a Trezor BTC address?

texts: I accidentally sent my BCH from Breadwallet to a BTC address from my Trezor wallet. Is there any way to retrieve that back to my BCH wallet? The BTC wallet I sent the money to is mine, so I own the keys but the address starts with 3.


texts: Mining new litecoin based altcoin. Internal Server Error 500

texts:
I apologise if I put this question in wrong place.

I created new altcoin based on litecoin source code.
All looks ok, wallet and wallet-qt are compiled and running.
However when I trying to mine using cpuminer (minerd) I getting 500 error.

I put this settings to *coin.conf file:

rpcuser=miner1
rpcpassword=some_password_here
rpcallowip=127.0.0.1
rcpport=9332
server=1
gen=0

Command for minerd:

minerd -a scrypt -o http://127.0.0.1:9332 -O miner1:some_password_here

Minerd output:

[2017-06-29 10:38:02] 1 miner threads started, using 'scrypt' algorithm.
[2017-06-29 10:38:02] HTTP request failed: The requested URL returned error: 500 Internal Server Error
[2017-06-29 10:38:02] json_rpc_call failed, retry after 30 seconds

What I'm doing wrong? Is there something else I have to do to "launch" my new crypto currency?

Thank you for your help.


texts:
According to this graph, the biggest miner is so big that combined with two of the three runners-up they would have more than 50% of the hashing power.

Is that to be considered a threat to the bitcoin network?


texts: Why do non-SegWit clients send witness data in the first place?

texts:
If SegWit leaves out witness data for backwards-compatibility, thus witness data isn't so important apparently, then why do clients even send that data in in the first place?

Aren't they making their transactions unnecessarily bigger and thus more expensive?


texts: Bitcoin MultiSig balance not showing under listaccounts

texts:
I added 2-2 MultiSig address into wallet via bitcoin cli (Testnet)

  addmultisigaddress  <'["key","key"]'> [account]

1 key of current wallet and other public key from different node wallet.

Account is showing

  0.000000

Although more than six confirmations on the transaction: https://live.blockcypher.com/btc-testnet/tx/297b6f6c14486e9eda1b2a04e20e3bd161758afeafa7d4b0109fa7fca11154ae/

Most importantly listaccounts not listing the account associated with the MultiSig address.

getaddressesbyaccount [MultiSigAccount] shows the MultiSig address created above.

How can I get the balance of MultiSig address via bitcoin-cli?

Edit 1:

What does this command return: $ bitcoin-cli -testnet validateaddress <your-multisig-address>?

{
  "isvalid": true,
  "address": "2Mv4iYeyQtVV1M7rqzgUc68QzQ21vy1o36Z",
  "scriptPubKey": "a9141eeba411eae41a1a3dc7456ec4d599aef84afd7687",
  "ismine": false,
  "iswatchonly": true,
  "isscript": true,
  "iswitness": false,
  "script": "witness_v0_scripthash",
  "hex": "00206e908e1cca44b136fbf666f356114ca6a84c1fbed0327a155c204580310a7a11",
  "embedded": {
    "isscript": true,
    "iswitness": true,
    "witness_version": 0,
    "witness_program": "6e908e1cca44b136fbf666f356114ca6a84c1fbed0327a155c204580310a7a11",
    "script": "multisig",
    "hex": "52210240d4ae4819e35e346560efe665f79453210a0b26184e08705964c5eb89e885ca2103fcc7e4690f7bd3a51db7ed438ef9a7ffb0bf316467f39b384935befee4eb208552ae",
    "sigsrequired": 2,
    "pubkeys": [
      "0240d4ae4819e35e346560efe665f79453210a0b26184e08705964c5eb89e885ca",
      "03fcc7e4690f7bd3a51db7ed438ef9a7ffb0bf316467f39b384935befee4eb2085"
    ],
    "address": "tb1qd6ggu8x2gjcnd7lkvme4vy2v565yc8a76qe8592uypzcqvg20ggslwnwl8",
    "scriptPubKey": "00206e908e1cca44b136fbf666f356114ca6a84c1fbed0327a155c204580310a7a11"
  },
  "addresses": [
    "tb1qd6ggu8x2gjcnd7lkvme4vy2v565yc8a76qe8592uypzcqvg20ggslwnwl8"
  ],
  "account": "multisig22",
  "timestamp": 0
}


texts: Why does my BIP32 implementation throw different results than other web implementations? They also disagree with each other tho

texts:
I am implementing bip32 for my wallet as a project to learn Bitcoin.

I am following this documentation:
https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki

Since I am not implementing bip39 yet, I am getting the master private key and code chain from the BIP39 Root Key from this web:
https://iancoleman.io/bip39/#english

using a random set of words which are:

praise vague cruise stem test gesture twin long donate violin special hamster horror rough loan

which throws:

xprv9s21ZrQH143K2E7weJFDreP9A8dFkx18swFoAJ6DBdsVuSPoFBLzekLca8vEG1i6ikCcvzZb79joaEZAjeM8Nz1DZ549aCnv3YFXy33mLoW

Comparing this output with another web implementation here: https://iancoleman.io/bip39/

These two outputs match. However, after this point they don't. And my implementation doesn't match with any of those implementations!

Here is my python code where I deserialize the BIP32 extended key. This matches perfectly with the master private key and chain code from the second web app:

def deserialize_xprvk(s):
    version = s.read(4)
    depth = s.read(1)
    fingerprint = s.read(4)
    index= s.read(4)
    chain_code = s.read(32)
    s.read(1)
    privkey = s.read(32)
    return [version,depth, fingerprint,index,chain_code,privkey]

decoded =deserialize_xprvk( BytesIO(decode_base58_extended(xtprvk)))

printing "decoded" I get:

0x488ade4
0x0
0x0
0x0
0x10e85c06826fdcd006c244ff6c44200044c1418bdd82cc088c33e48ae7b4c2ca
0xf214c0afd9b311544fdb686cae5100f1ac0ac8aba2b6c55719ba41ac2d4f2d12

which matches perfectly with the 2nd implementation (the firs one doesn't show the master private key or chain code).

Then I try to follow the instructions from here:
https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
to derivate the child PRIVATE KEY with index 0 for this master key and chain code like this:

#The order of the ciclic group in the finite field of the ecliptic curve
N = 0xfffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141

#creates a string to emulate the index in a 4-byte hex format.
def str_i(i):
    i_str = hex(i)[2:]
    while len(i_str)<8:
        i_str="0"+i_str
    return i_str

pub_key = PrivateKey(int.from_bytes(master_priv_key,"big")).point.sec()

#I put an extra "0" because every public key begins with a "02" or "03" but
#the hex() function commits this character.
#The str_i(0) means I am trying to get the index 0.
msg=("0" + hex(int.from_bytes(pub_key,"big"))[2:] + str_i(0)).encode()

I= hmac.new(
            key = hex(int.from_bytes(chain_code,"big"))[2:].encode() ,
            msg=msg ,
            digestmod=sha512).digest()

I_L, I_R = I[:32], I[32:]

child_privkey_int = (int.from_bytes(I_L,"big") + int.from_bytes(master_priv_key,"big"))%N

child_privkey = PrivateKey(child_privkey_int).wif(compressed= True)

child_chain_code = I_R

If I run this code and try to get the child private key for path m\0\0\ I get:

"L29Rc5PyDkbUr2z1VcL2DuAhTQkNo3qwF7ENgRotS86ADUkiXPJF"

But in the first web app they get:
"KwuPS3DGMnCc3jMJWtqVVzkCoMyhybxGZrf68fPBEBtFfujBdPGs"

And in the second one they get:
"L1TcvgkPZFa6DyXhv9vYWceTXZhoAR7ZQMdt5rqV6LW3Zutpsqr8"

Is it ok to disagree on different implementations?? or am I doing something really wrong? I am starting to pull off my hair trying to find out where I am messing up.

Thanks.


texts:
I am trying to create a website that allows the deposit of cryptocurrencies (BTC / ETH / LTC) in the account, consequently I need to create a wallet at the personal registration for each of these 3 cryptocurrencies.
I would also like it to be possible to send crypto through the wallets registered on the site (p2p) and the possibility of receiving / sending crypto.
How can it be done? Is it possible to do this in PHP?
Every post I found on the forum is very old, probably a lot of things have changed.


texts: Error: Prune mode is incompatible with -txindex


texts: When does transaction output become usable?

texts: Say, I've generated, signed and sent raw transaction (via JSON-RPC) to the network. The call resulted in a transaction hash. When can I use the output of that transaction: when the transaction will be confirmed at least once or when it'll be in the blockchain?


texts:
After following the instructions here, which suggested I use ykpers or the gui version, I discovered the Mt. Gox Yubikey is protected by a "configuration protection access code."

From the manual:

  Protection of the key and configuration data

  Given the symmetric nature of the AES encryption algorithm, the
  security of the Yubikey relies that the AES key is logically and
  physically protected both in the key and in the server that verifies
  the OTP.

  The configuration data is updated via a configuration API, accessible
  via the USB interface. To prevent unauthorized update, the
  configuration can be protected by a 48-bit access code. If used, an
  exhaustive search of all combinations would typically take some
  100,000 years to perform. Furthermore, the Yubikey configuration data
  is write-only, i.e. configuration data and the key can only be written
  but not be read. This means that unauthorized update of the
  configuration is an act of sabotage rather than a security threat.

  The configuration data is stored in a non-volatile storage integral to
  the microcontroller. A potential attack is to physically probe the
  silicon or analyze the hardware behavior to potentially gain full or
  partial knowledge of the stored secrets. However, such an attack would
  require a complete break-up of the Yubikey, involving dissolving the
  microcontroller chip encapsulation. Furthermore, very advanced
  equipment is needed to probe the chip internals. Given the effort and
  costs involved for such an attack, this is not considered a threat
  given that just a single device will be broken.

Yubikey wrote me:

  In case, if you have forgotten the configuration protection code or do
  not find it in the log file, then you can not reconfigure the YubiKey
  slot again. This functionality is implemented to strengthen the
  security.

Also, he wrote:

  In the context of the manual, an "unauthorized update of the
  configuration" would be changing the configuration settings on an
  unprotected YubiKey. Since you already have an access code in place,
  you cannot preform such an update.

But it should still be possible to "sabotage" a Mt. Gox Yubikey, no? If not, why? If so, how?

thanks

What is also strange is that when I try to create an account at forum.yubico.com or test my Yubikey at demo.yubico.com, they reject my OTP. Yubico Forum's registration says my OTP can't contain non alphanumeric characters, and it sometimes contains periods. [Update: this ended up being because I was using Dvorak keyboard layout for the Yubikey. I've changed it, and now my OTPs work on these sites.]

UPDATE #2: I found this: https://github.com/nezza/yubicrack
But there has to be a quicker way than doing a brute-force search of the code. I really wonder why it is so hard to flash a Yubikey? Is it so that others can't render it effectively "lost" or "stolen"?


texts: Are there any other ways of speeding up the building of Bitcoin Core PRs other than ccache?

texts: I am already using ccache to speed up recompilation when building Bitcoin Core PRs. Are there any other ways of speeding up the process?


texts:
It seems that if most transactions are valid, a miner could save a little time and increase its chance of mining a block by not validating.  Is the reason that there are enough invalid transactions to make this an ineffective strategy, because the risk of having mined an invalid block is not worth the time savings?

I have a similar question about verifying/validating blocks, and maybe the answer is similar, too.


texts: what is the Difference between ./bitcoind and $ ./bitcoind -daemon?

texts:
I was trying to interact with bitcoin network with JSON RPC commands, So I referred to the bitcoin wiki page https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)#Java it shows to run the bitcoin using 'bitcoind -daemon' command. but another page of bitcoin wiki https://en.bitcoin.it/wiki/Running_Bitcoin suggest running the node using './bitcoind' command.so
 What is the difference between the two commands?


texts: OP_Return in transactions at json_rpc_api at blockchain.info

texts:
I am writing a project in Ruby using JSON-RPC to communicate with blockchain.info. The API is available here: https://blockchain.info/api/json_rpc_api

Is it possible to create a op_return txout using the given JSON-RPC API ?


texts:
Satoshi has never really justified or explained many of these constants.

it is someone found out about this constants yet?

link: https://en.bitcoin.it/wiki/Controlled_supply


texts: Is there a service that alerts about attempted double spends for merchants accepting 0-confirmation transactions?

texts:
I often come across merchants accepting payment in bitcoin, who require several confirmations on transactions, but where the probability of a successful double spend doesn't justify the waiting time for the user. A good example is membership payment for adult sites, where the membership can easily be withdrawn in case of a double spend, and not much is lost if a double spend is successful.

A part of the reason they do this, I think, is that they don't have a good way of knowing if a user is attempting to double spend coins sent to them.

Is there a service available that allows merchants to be notified of double spends of coins sent to them, so that they can be notified in case this happens, and take action - for example by banning the user, or just temporarily removing the deposit to an account until the transaction has 6 confirmations?

A simple service could be one where the merchant enters their deposit address at a web service, and the web service simply responds with the amount of attempted double spends, ie. if any of the inputs to the transaction that sends funds to the merchant's deposit address are attempted spent in another transaction, the request will return a number above 0.

Does such a service exist?


texts: upgrading bitcoind (-qt) from 0.9.3 to 0.10

texts:
I have version 0.9.3 of bitcoind (-qt) on my Ubuntu server and I want to
upgrade to 0.10.0, I just want to keep the blockchain and I have nothing in my wallet.

from https://bitcoin.org/en/release/v0.10.0, I found
"or just copy over bitcoind/bitcoin-qt (on Linux)"

If I do

sudo find / -name '*bitcoin-qt*'
/usr/local/src/bitcoin-0.9.3/src/qt/res/bitcoin-qt-res.rc
/usr/local/src/bitcoin-0.9.3/contrib/bitcoin-qt.pro
/usr/local/src/bitcoin-0.9.3/contrib/debian/manpages/bitcoin-qt.1
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoin-qt.lintian-overrides
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoin-qt.protocol
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoin-qt.install
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoin-qt.desktop
/usr/local/bin/bitcoin-qt
/usr/local/bin/test_bitcoin-qt

I find few files in .../bitcoin-0.9.3/...I guess those files have been used to compile the binary file /usr/local/bin/bitcoin-qt.

Then I can replace the binary bitcoin-qt with the new one in /usr/local/bin/ and remove everything in bitcoin-0.9.3? Is it correct ? Same question for bitcoind:

sudo find / -name '*bitcoind*'
/usr/local/src/bitcoin-0.9.3/src/bitcoind.o
/usr/local/src/bitcoin-0.9.3/src/bitcoind.cpp
/usr/local/src/bitcoin-0.9.3/src/.deps/bitcoind.Po
/usr/local/src/bitcoin-0.9.3/src/bitcoind-res.rc
/usr/local/src/bitcoin-0.9.3/src/bitcoind
/usr/local/src/bitcoin-0.9.3/contrib/bitcoind.bash-completion
/usr/local/src/bitcoin-0.9.3/contrib/debian/manpages/bitcoind.1
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoind.manpages
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoind.examples
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoind.install
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoind.bash-completion
/usr/local/src/bitcoin-0.9.3/contrib/debian/bitcoind.lintian-overrides
/usr/local/src/bitcoin-0.9.3/qa/pull-tester/run-bitcoind-for-test.sh.in
/usr/local/src/bitcoin-0.9.3/qa/pull-tester/run-bitcoind-for-test.sh
/usr/local/bin/bitcoind

And last question: what do I do with all those files in the .tar.gz archive downloaded from the web:

bitcoin-0.10.0/bin/bitcoin-cli
bitcoin-0.10.0/bin/bitcoind
bitcoin-0.10.0/bin/bitcoin-qt
bitcoin-0.10.0/bin/bitcoin-tx
bitcoin-0.10.0/bin/test_bitcoin
bitcoin-0.10.0/bin/test_bitcoin-qt

bitcoin-0.10.0/include/bitcoinconsensus.h

bitcoin-0.10.0/lib/libbitcoinconsensus.so -> libbitcoinconsensus.so.0.0.0
bitcoin-0.10.0/lib/libbitcoinconsensus.so.0 -> libbitcoinconsensus.so.0.0.0
bitcoin-0.10.0/lib/libbitcoinconsensus.so.0.0.0


texts: Are there any Mining OS to be started from USB?

texts:
Considering my PC as a mining rig I don't want to install anything on HD. Setting up a system with full GUI mining capabilites (proprietary drivers, OpenCL, ...) can take some time. An out of the box solution would be nice.

Are there any preconfigured OS distributions (maybe Linux) containing all you need to boot and mine without further configurations?


texts:
Bitcoin 0.14

Friends, tell me how you can mining without a pool at home on your computer?
I have bfgminer and cgminer
I'm trying to connect so

D:\bfgminer\bfgminer.exe -o stratum+tcp://localhost:18444 -u login-p password

D:\cgminer-4.10.0-windows\cgminer.exe -o stratum+tcp://127.0.0.1:18352 -u login -p password

but it does not work:(

bitcoin.conf

regtest=1
server=1
daemon=1
rpcuser=login

# Alice connects to Cory
connect=localhost:18444

rpcpassword=password
rpcallowip=127.0.0.1


texts:
When I run bitcoin-qt from CLI I get a nice Bitcoin icon with distinct colors for main and testnet.

I want to create a .desktop file to run it from Gnome, how can I configure the icon to be the same?
I don't seem to find those icons on the release files to reference.


texts: Trying to download miner but Google Chrome marks them as malicious/malware

texts:
First I tried GUIMiner-scrypt and then cgminer-3.9.0-windows.zip

Both archives are marked as malicious in Google Chrome. I googled and have not found articles about that. Do other people get such warnings while downloading miner?

UPDATE

My links are 2 top google results
@TinS gave another download link and file is name is same guiminer-scrypt_win32_binaries_v0.04.zip but size is different.

One file is marked as malicious by Google Chrome and another not.


texts: Confused on using SHA256 code from Bitcoin Core

texts:
I was looking at Bitcoin Core code to use its SHA256 code but am confused on where I should be looking at.

In bitcoin/src/crypto/sha256.h there is CSHA256

and in bitcoin/src/crypto/sha256.cpp there are namespaces named sha256_sse4, sha256_shani.

And then there is bitcoin/src/hash.h

Explanations and guidance would be greatly appreciated.


texts: To use Dwolla with Mt. Gox I need to become Verified. Do I need Apostille?

texts:
Mt. Gox now requires at least Level 1 Verified in order to deposit or withdraw Dwolla funds.

Level 1 says Government Photo ID + utility bill

http://en.bitcoin.it/wiki/MtGox#AML
https://support.mtgox.com/entries/20919111-aml-account-statuses

But then I see an update saying an apostille is needed.  Is that just for a Level 2 (Trusted) account?

http://support.mtgox.com/entries/20861901-changes-to-aml-policies


texts: Any guidance to built Simple and Basic trade engine?

texts:
I want to know how the trade engine works, sites likes cryptsy seems to have trade engine to automate the trade process, At first coin-swap seems to have option for "Accept Trade", but now this also has been changed now it works similar to cryptsy, no option for Accept Trade, suppose i create a buy order in cryptsy it automatically match with sell order then i will get my buying currency

How the trade engine withdraw/deposit coins?


texts: How many currency units in 1xBTC / 1xAltCoin?

texts: Since BitCoin (and AltCoins) are divisible by up to 8 decimal places, does that technically mean that 1xBTC (or 1xAltCoin) is equal to 1 billion individual units of currency?


texts: How do I view the list of all existing Unspent Transaction Outputs, not just for my wallet, with Bitcoin Core utilities or any other software?

texts:
I'm preparing data for a research/analysis, and I'm a bit new to bitcoin-cli. I need to obtain data for the chart like this:
https://www.blockchain.com/charts/utxo-count
, with only difference that it will display not UTXO count, but it's summary value in BTC for the given timestamp in further (meaning that the script will count only present date/time, not historical data). I've already enabled txindex.
What I've tried:

bitcoin-cli listunspent - doesn't work for me, since it displays only in-wallet outputs (correct me, if I'm wrong) `
bitcoin-cli gettxout ... - I know how to use that command, but to prepare all the existing unspents, I will need to loop over all of the transactions were ever made, and it takes too long; however, if there's no other way, I'd rather do it.

I know little about how UTXO work, and I believe there must be something I'm missing. I don't think that for every minute I will need to re-calculate the whole historical transactions to find out the summary volume of their unspent outputs. I also understand that Bitcoin researches is not main purpose of Bitcoin Core utilities, so I can understand if there is no easy way included.
However, if you have some tips on how could I achieve what I described, I'd be the most grateful. At best, I'd like to know what's the fastest (execution time, I mean) way to calculate all the globally existing UTXO value (volume). At least, knowledge how to get the list of unspent outputs for every transaction ever made.


texts:
Are "move" operations logged somewhere in the wallet or somewhere else?

If so, can the "move history" be retrieved, and how?

edit: apparently the command listtransactions lists some move operations, but not all, and I have no clue if there is some criteria, or it is simply bugged.


texts: Accepting Bitcoin for Services Rendered with Legal Verbiage on Set Coin Price

texts: I accept Bitcoin and Ethereum for consulting work, but would like some feedback for Service Type Agreements that span upwards of a 1-year in an enterprise setting. What's the best method for approaching set coin prices in a legal service agreement where the markets can fluctuate?


texts: How many Bitcoin addresses can Bitcoin Core create? Is there a limit to number of addresses Bitcoin core can crate? Can I use one receiving address for multiple transactions?


texts: What is the approach to calculate an Ethereum address from a 256 bit private key?

texts:
For a given private key generated by MyEtherWallet, I would like to see I have the tools to independently arrive at similar results.

Wrote a wrapper around Keccak to accept both hexadecimal and ASCII inputs to be sha3-224 or sha3-256 or  sha3-384 or sha3-512 hashed. Hashes are consistent with Test Vectors. Would like to apply it with bitcoin-explorer (bx) version3 commands to see if I can synthesize ETH addresses. If successful at synthesizing addresses for ETH, XMR, and MAX altcoins, I go through the effort of submitting a pull request to add sha3 hashing capabilities to bx version3, and update this Wiki concerning the application of bx to altcoins.


texts: Bitcoin Core V 0.10.0: Is there a way to force send when not synchronized?

texts:
My Bitcoin Core is not yet synchronized, but I already attempted sending a transaction, so now it is 'conflicted'.
I can see this conflicted transaction is not being propagated.
Is there a way to force the sending of that transaction?
I know for sure that whatever input it will use, that transaction will be valid.

Thanks!


texts: Source code for SPV node on iOS - where to start?

texts:
I'm working on a proof-of-concept for a blockchain project and at its core it will need a modified SPV node running on iOS. The reason I need to modify it is so I can build non-standard (e.g. OP_RETURN) scripts without seat-of-the-pants techniques like hacking into the transaction hex.

I'm aware of some basic starting points such as picocoin and libbitcoin which I should be able to compile for iOS. But is there anything else available that would specifically make an SPV node easier to develop on iOS?


texts: How similar is Blockchain (as a data structure) to double linked list?

texts:
I came across this definition of Blockchain from Oleg Andreev , who is the protocol architect of @chain -

It felt like double linked list to me.


texts: New transaction, merkle tree change, when to decide what to include in new block

texts:
As I understand the merkle tree hash is a (semi)unique hash of the combination of the new transactions and the previous blocks hash.

I'm assuming this hash changes when a new transaction is added to the block. Now since there are multiple transactions per second on average (with BTC), this means the nonce is "reset" each time.

As I've understood here: Restarting mining on new transaction 'restarting' is not really a valid concept, since every 'try' for mining a block is the same probability chance.

Since everyone would want to have the newest block to include as much transactions as possible, how is this managed.

Is it wrong to see it like this:

Every miner hopes to find a new block in 1 second (which means billions of nonces tried if I understand correctly, given you have a fast miner).
If it doesn't find the nonce in that 1 second, it will grab as many new transactions as possible, and starts bursting out new block hashes, until one is 'difficult' enough. And then advertises that block and everyone will have to verify and then accept/deal with this amount of transactions in the new block.

Is it wrong to think that it doesn't really matter if a miner spends 5 minutes on the same block, or switch to a new block every second or even faster? Since the probability is the same.

My question is basically if there is anything wrong with the above statements or assumptions.


texts: Can I still claim BCH from BTC core wallet after the 'BCH November 13' fork?

texts:
I run a full BTC core node and use the bitcoin-qt core client wallet.

I have BTC in this wallet from before BCH was created. I have not yet attempted to claim my BCH.

After the upcoming bitcoin cash BCH November 13 hard fork upgrade activates, will I still be able to claim bitcoin cash (sweep or import from BCC to BCH wallet) from my bitcoin-qt (BTC) wallet?

I assume I can, but have not been able to find an explicit answer to this. I want to be certain I can claim BCH after Nov 13.


texts: How exactly would anyone know from where I got a given "bit of Bitcoin", or who I send it to?

texts:
Let's say I buy 0.1 BTC using Bisq. Okay, so the person I bought it from will know my name since I have to give it up to make the international bank transaction. And I will know their name because that's how Bisq works and apparently has to work. Alright.

Us two strangers know each others' identities.

So, does this mean that the person I bought the 0.1 BTC from now can track exactly how I spend it? How? Isn't the truth that, at best, they can see when I spend it (if ever) and which "receive address" received it? Which tells them exactly nothing whatsoever?

Ever since I first heard about Bitcoin, over a decade ago, I've been trying to get clear answers on the most fundamental questions, but never receive anything but assumptions/guesses or such technical and in-depth explanations that they might as well be made up and I couldn't tell the difference between that and the truth.

The most common "explanation" is to vaguely state that "it's completely trackable and 100% non-anonymous", but that seems to be utter nonsense to me. It actually seems to be very anonymous. The person I bought the 0.1 BTC from cannot possibly know if I'm selling it, paying for something, or just moving it to another wallet of mine. They have no clue. It's just a gibberish string of computer-generated characters -- not a full name and address and photo id in a neat little digital package.

I seriously believe that only a handful of people in the world truly understand how Bitcoin works on any deeper level, and that all the others are just pretending in order to not be seen as "stupid". Like the old tale of the naked emperor.


texts:
I sent a bitcoin transaction and after sending it I realized that the fee was too low.

https://www.blockchain.com/btc/tx/a398c4a2db165bd35435e381a6d185a14aa7a3df40aeca157dd89e4efd2e20d1

in an attempt to correct it, later on, I sent another transaction to the same address with a higher fee.

https://www.blockchain.com/btc/tx/92b33d498a35d47f03eee14f258cf9b3f015a5d12856eb05e47534e664344239

as I read about Child pays for Parent, but still it didn't work. The second transaction went through and the first one is still there. Did I do something wrong? Is there anything I can do to correct it?


texts:
I was reading about CPFP (child pays for parents) recently and I didn't completely get the concept of it.

Can someone please give me a brief explanation of how it should be done and what are the wallets that currently support it?

Is my understanding of CPFP even correct? A user sends a transaction to another, which is not confirmed, that user can send another transaction that is "connected" to it with a high fee, that when a miner mines it, they are forced to mine the first, unconfirmed transaction?


texts: How can you tell how many users Bitcoin has?

texts: Impossible to answer accurately, but I suppose one could come up with educated guesses and ballpark figures from the number of nodes on the network, or number of users on popular wallet services.


texts: How the hell was I able to receive BTCs via an address I do not own?

texts:
A few minutes ago I received 0.00000001 BTC. I don't know who sent them or why.

But what makes it crazy is, this sum was sent to an address I do not own and which the client I'm running (the standard Bitcoin-QT, versione 0.8.5) had never heard of before. I know this for sure because I only created 2 (two) addresses using this client, and the receiving address of this transaction is not one of them.

How is this possible at all?
Is it a hash collision, or what else?

The address is 1Cz2AmLe8U52KR549d13JQkqsqkV64RchB and the transaction ID is b9591410ff030e40deb3eda9d2fe30a29642ede443f354bb5f4ed5bb55f0d36d.

According to this page, the address seems to have received money a little time before from 1HTawQNCS4axPXft6L6fkzrv5ya7TguqwD, which actually is one of my addresses; the last two transactions are me sending all my BTCs to a new address, just to be sure. This worked, so it looks like I'm actually the owner of that address, even if my client doesn't list it as one of mine.

What's exactly going on here?


texts: What is anonymous and safe api to get bitcoin Exchange Rates?

texts:
What is anonymous and safe api to get bitcoin Exchange Rates like BTC/USD and BTC/EUR without trace my ip ?

i used tor service, i search and found blockchain api contain Exchange Rates Feed

http://blockchain.info/ticker

is this secure means if i use this api, can blockchain trace my ip(tor) ?

and how can i use this api in php ?

and if anyone have others api provides bitcoin Exchange Rates Feed please tell me ?

thanks


texts:
So, I have been mining LTC with a custom rig (see below for hardware details) and this morning it was down. When I restarted it, it worked fine for two minutes then shut down again without beep nor blue screen. Here is what I have try to understand where the problem comes from.

Tried a different power bar
Let the PC run without the miner software enabled (PC don't crash in that case)
Let the PC run with the miner but only 3 GPUs working (PC don't crash in that case)
Let the PC run with the miner but 4-5-6 GPUs working (PC crashes)

I have few hypotheses.

Add4PSU which plug the two PSU in serie doesn't work: I don't know if the 6 GPUs would start in that case, however, since three are plugged on the second PSU.
For some reason, heat make the PC shut down (sensors broken or something strange)
One of the PSU can't get enough power when the GPUs work at 100%

I do not know if someone has any idea. I'll post this also on superuser stack. Here is my hardware:

Mobo: MSI Z77A-G45 ATX LGA1155 Z77 DDR3 3PC I-E16 4PC I-E1
GPU: 6 PowerColor PCS+ AX7950 3GBD5-2DHPP Radeon HD 7950 3GB 384-bit GDDR5
CPU: Intel Celeron G1620
Mem: 2 Viper Xtreme 1600Mhz, 2GB
PSU: 2 Corsair Professional HX850W 850W ATX 12V 70A 24PIN ATX Modular (Gold rated, plugped with Add2PSU)


texts:
I'm considering the development of a lightning app, and I'm trying to make it non custodial.

I was thinking on pre-generating invoices for all users every x time to make things simpler. To do that I'd need to extend the expiry date.

I tried to look up why do lightning invoices expire, and I couldn't find a clear answer.

Why do lightning invoices have an expiry date?

Is it to ensure that they are not kept forever in the receivers DB? or is there another reason?


texts: Block 620826 is 1 second before block 620825?

texts: How does that happen?  Obviously the miner of 826 built his block on top of 825, but why is the time 1 second earlier?


texts: Instawire fees over Bitcoin Central fees and their respective KYC policies?

texts:
Instawire, Bitcoin-Central, Instawallet, Paytunia and Paymium are seem to be closely related, they cross reference each other on their sites, though their respective guarantees for their services are quite different (that was two links in two words just it's difficult to see it on your platform, perhaps you can fix that) which is interesting.

The question is why Instawire charges much more than the prices you can get on Bitcoin-Central? Maybe because the first one is a service and the latter one is an exchange. But perhaps do they have different KYC policies? Though I'm not sure about Instawire' KYC (Know oyur customer) policies they state on their site that you can send up to 100 euros, though, for a high fee. Maybe you pay for your privacy with this service? On the other hand, Bitcoin-Central requires your personal documents for even the smallest transactions, right? Though I'm not sure, didn't find these data explicitly on their sites.


texts: How to recieve bitcoin fork (segwit2x) on binance?

texts: I cannot find any area on Binance.com that shows the new bitcoin hard-fork (segwit2x) funds, any input?


texts: Which full node implementation(s) supports SegWit

texts:
I just finished setting up a full node using bitcore.io's guide here. I need my node to support SegWit though and I am not entirely sure whether what I have set up offers SegWit support. Especially after reading this article: What Bitcore Users Need to Know To Be Ready for Segwit Activation.

Is this the correct choice of a full node platform for me to have SegWit? What other options do I have?

Note: I have a wallet based on Copay who's builders also maintain bitcore.io so their full node software was my first/obvious choice


texts: Is a Trezor hardware wallet dependent on wallet.trezor.io?

texts:
A review of the Trezor hardware wallet says:

  In order to access your coins, you would simply do so by connecting your TREZOR to your computer and power up the TREZOR wallet interface at https://wallet.trezor.io. From here, you can see your balances, generate addresses for payment, and send payments.

If trezor.io disappears for any reason, is the Trezor hardware device useless? Are there other ways to spend cryptocoins tied to the private key in the Trezor that don't depend on trezor.io?


texts: Is it possible for an individual to start their own blockchain working with Bitcoin Core?

texts:
Is it possible for an individual to create their own blockchain from
Bitcoin Core?

I think the value of BTC is currently controlled by miners in China and I want to create a blockchain with either a filter on who can mine or a limitation on the amount each individual can mine.


texts:
I have a Qt testnet3 node synched and running on my mac.  In the terminal, when simply trying:

$ bitcoin-cli getinfo

or

$ ./bitcoin-cli getinfo

I get:

-bash: bitcoin-cli: command not found

Anyone know why the command could or would not be found?  (server=1 in bitcoin.conf as well)


texts:
I have read a lot about how to build and tune hardware for script mining, but it is still unclear to me how to trade what you have produced for real money.

I need some help in order to put together the parts of the big picture. So, I want to mine dogecoins. Using a web site I can connect to mining pool for dogecoins. So, these all mined coins should appear in my account there, right?

Then, using this tutorial it is said that using an "auto-sell" strategy with Cryptsy is nice. I can't get how both are connected - is Cryptsy used to transfer what you have produced to BTC? And where is the part when the coins are transferred to money?


texts: bitcoincore banned all peers and I can't to sync

texts:
I started downloading the chain and got to 14% and it just stopped and still shows 7% per hour but not moves.

I checked and it banned all the peers and everytime I unban them they just get banned again, what is happening ?


texts: Are there any services hosting Bitcoin-related ads for websites?

texts: Say one owns a Bitcoin-specific website and they want to get some ad revenue for Bitcoin-related ads. Are there any websites that host such ads and provide the necessary code for displaying and monetizing them, just like AdSense would, or does one have to contact individual Bitcoin websites and strike deals with them?


texts: Generating Bitcoin address from private key in browser console

texts:
I am a newbie Bitcoin evangelist and I have a recommendation to see all the code responsible for computing yourPublicKey from yourPrivateKey, especially for big deal addresses.
The easiest way to allow Bitcoin users to see the code is to write it in Javascript to let them run it on console, because any PC user has a browser and almost nobody has Python or any other interpreter. I saw a step-by-step manual in this answer to How can I generate a bitcoin address? but I still have some obstructions to produce one single sheet of code ready for running in console.
Please help me to write that code to make my recommendation easy to follow.


texts:
I received a transaction which has been unconfirmed for 36 hours with 0 confirmations. I'm relatively new to btc and having had a relatively speedy, problem free experience so far I'm not sure what to make of it.

Any help would be welcome.

Thanks.

https://blockchain.info/tx/751bd6c180fac5c1b54ba428d2b4416a13ecefd978193e5dc8138f5b0de56f86


texts: What are main advantages of Bitcoin over Monero?

texts:
In the world of full spectrum surveillance, since some time it has become more than evident that Bitcoin isn’t that anonymous at all. All transactions can be traced on the blockchain. There is a certain probability that this data can be handed over to big brother governments upon request, and your commercial connections with certain people, products or online services -- would be easily revealed.

Some of the bitcoin blockchain monitoring companies do deanonymize bitcoin users and their commercial activities.

So, what would be the main advantage of Bitcoin over Monero?


texts: Installed Bitcoind on my Ubuntu server, but where does the blockchain get downloaded?

texts: I have a fresh install of Ubuntu 12 and just installed bitcoind. How do i find out where its installed and where is it downloading the entire blockchain?


texts: if the hardware wallet company ledger goes out of business, what will happen to my crypto asset / private keys in ledger? I heard that the hardware wallet ledger is not open-source, so will the company get access to my private key? Will I be able to transfer my crypto elsewhere?


texts: How does an encrypted wallet persist used keys from "getnewaddress" and the keypool after a restart?

texts:
I'm reading this wiki on wallet encryption  and am confused on how I can call getnewaddress as described here and where that is being tracked after a restart of bitcoind.

  When a wallet is encrypted, the passphrase is required to top up the
  keypool, thus, if the passphrase is rarely entered, it is possible
  that keypool might run out. In this case, the default key will be used
  as the target for payouts for mining, and calls to getnewaddress and
  getaccount address will return an error. In order to prevent such
  cases, the keypool is automatically refilled when walletpassphrase is
  called with a correct passphrase and when topupkeypool is called
  (while the wallet is unlocked). Note that the keypool continues to be
  topped up on various occasions when a new key from pool is used and
  the wallet is unlocked (or unencrypted).

  When wallet passphrase
  enrcyption becomes enabled, any unused keys from the keypool are
  flushed (marked as used) and new keys protected with encyption are
  added. For this reason, make a new backup of your wallet so that you
  will be able to recover the keys from the new key pool should access
  to your backups be necessary.


texts: How do I delete the blockchain after uninstalling Bitcion Core?

texts: I downloaded bitcoin core, and it "synced" the blockchain, taking up 163gig on my HD considerably slowing my comp. so I uninstalled bitcoin core, but yet still see to have 163gig of unwanted data slowing my computer. I operate Windows 10. HOW do I get rid of it. It seems to be in my users file, but mysteriously doesn't show up when trying to locate it?


texts: If I am trying to find a nonce and in the meantime someone finds a nonce and adds a new block to chain, then will my work be wasted or it could be useful in finding other nonces?


texts: Why does Binance use USDT instead of USD?

texts: binance seems to have BTC-EUR but no BTC-USD. I can see BTC-USDT. Is this the closest one to trading BTC-US dollar?


texts:
Good day,

can someone maybe help me.
I just opened my wallet today after I exported it to a private key and incrypted it (Multibit wallet) and more than half of my coins has been send out to an address I dnt know. According to what I can see in the transaction History of this transfer it has been used as transaction fees for someone els`s transfer of coins.
Can this be a problem on the blockchain side or was my wallet hacked.
Any help will be greatly appreciated.

Thank you


texts: How to "create new receiving address" from recently installed full node, (0.21.0) with new encrypted wallet?

texts:
On March 11th, 2021, I completed my downloaded of the full node from Bitcoin Core, (Bitcoin-0.21.0-win64-setup), on my Intel(R) Core(TM) i7-10700 CPU @ 2.90GHz - 16.0GB,  Windows 10Pro.
I created a new wallet with encryption and I named it.
The "get new address" box remains grayed out.
After unlocking with "passphrase" [] 100),
Console command "getnewaddress" was unsuccessful.  "update" says I'm wallet version 169900.
Node is fully synced and has remained in operation, with "check box" saying up to date, and with 10 active connections to Bitcoin network.
I haven't seen any new problems reported, with this issue, since 0.21.0 release.  I'm pretty sure I've tried and was unsuccessful with all other suggestions for the same issue.
Any ideas are greatly appreciated.  Further, I'm a boomer noob, who left programming after the mouse was introduced.
Uggh! Wondering if I should delete node and start over without encrypted wallet?