texts: MtGox http api "trades since" requests keep being timed out

texts:
i wrote a simple function to retrieve trades from mtgox with following HTTP API call:

https://data.mtgox.com/api/1/BTCUSD/trades?since

documented here: https://en.bitcoin.it/wiki/MtGox/API/HTTP/v1#Multi_currency_trades

here's the function:

string GetTradesOnline(Int64 tid)
{
    Thread.Sleep(30000);

    // communicate
    string url = "https://data.mtgox.com/api/1/BTCUSD/trades?since=" + tid.ToString();
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    StreamReader reader = new StreamReader(response.GetResponseStream());

    string json = reader.ReadToEnd();
    return json;
}

i'm starting at tid=0 to get the data from the very beginning. it works fine for 5 requests & responses. but then the following line throws a "System.Net.WebException", saying that "The operation has timed out":

HttpWebResponse response = (HttpWebResponse)request.GetResponse();

this exception keeps being thrown even if i catch it and retry. it's always exactly at 5 requests.

while it has been failing for a couple of minutes, i try the 6th request in the browser and it works just fine while the function continues to fail.

the strange thing is that it works for 5 requests everytime i start the application. currently, i always start at trade id 0 (tid=0).

i've increased the Sleep() inbetween requests to 2 minutes but it still behaves the same.

if i change the url to https://www.google.com, it doesn't timeout.

any ideas of what could be wrong?


texts: How to create (many address)/receive/send bitcoin without download blockchain?

texts:
I need to create a lot of address on my wallet to get bitcoin.
Check balance and make transfers.

I do not have a hard disk of 200 GB, can I use bitcoin without downloading the blockchain?

Need implementation on NodeJS, or at the command line.


texts:
Understand that each proof of work algorithm has its pros and cons.

Difference between Hashcash proof of work algorithm and Ethash proof of work algorithm?

Nathan Aw


texts: Last time to send Bitcoin to Trezor before fork

texts:
What's the last safest time I can send bitcoins to my trezor for the upcoming bicoin gold fork? I'm asking because I want to maximise the benefit from price fluctuation on my exchange since I'm trading.

Thankyou


texts: how to see bitcoin blockchain and addressess for testnet

texts:
in my site the user has a link to check the transactions and his wallet address.

right now I am using this:

blockchain: https://blockchain.info/tx/#{txid}

address_url: https://blockchain.info/address/#{address}

and works perfect for btc mainnet

in my code I have this to get the blocks and addresses info, my question is how can I get the same thing but using testnet?

I tried https://www.blockcypher.com api but did not work, any help? thank you.

what I want it is get the transactions and addressess info from their in my website.

it is already working but just with btc main chain

I am using testnetchain already: bitcoin.conf testnet=1

can someone one explain how to get this info using the testnet?

is blockcypher or another website similar to blockchaininfo to me get these parameters.


texts: Bitcoin arbitrage, what do exchange office alows you to cash out?

texts:
I am wondering, if I do BTC arbitrage, meaning I buy BTC in one exchange, send to a second exchange and sell for FIAT, does the second exchange have any problems with me doing this? Because I will be only using them to sell  my BTC, so I will be cashing out a huge amount of money every month.

What is your opinion on using exchange office just to cash out?  And what do you think, they let you cash out monthly?


texts: Does anyone know of any surverys/statistics on the Bitcoin ownership demographics?

texts: I've only been able to find stuff from coin.dance, but was wondering if any of you have stumbled upon better data.


texts: What happens to my transaction if it is not accepted by miners?

texts: Let's say I haven't any fee or I paid a little fee. Miner didn't accept my transaction and still haven't got one confirmation. What will happen to that transaction? Will it rollback or Will it be in an unconfirmed state forever? Please explain.


texts: How to convert regular transaction to MULTI-SIG one?

texts:
Assume, I received a bitcoin in a regular transaction: T1. But I need to make MULTISIG transaction. so there should be at least n out of m signatures in new transaction :T3, to redeem it.

Am I right that to turn T1 to a MULTI-SIG one I need to do as follows:

1- I create new transaction T2, that points to T1, and includes all the m public keys and it pays to myself.

2- When I want to pay someone, I create new transaction: T3 (pointing to T2) includes n signatures and pays to another party.


texts:
I need a guide for single masternode, on an Ubuntu 16.04 64bit server (VPS) running headless and will be controlled from the wallet on your local computer (the Control wallet).

Thanks


texts: Does blockchain have any value if you trust all nodes?

texts:
If we are designing a new project or application whatever it is, and you can trust all nodes, should we still consider blockchains in the architecture?

I saw this video of IBM and I was wondering why choosing blockchain as a solution

https://www.youtube.com/watch?v=tdhpYQCWnCw&lc=z23mitvo0ki5sgplm2hd0syvq1wb1yadphkj5vl0mj00u00c2.151904784581

Wouldn't regular database solve the problem either way?

Could somebody explain?


texts: Do mining clients affect efficiency of mining?

texts: Excuse my ignorance. I'm new to this. When trying to start mining, does it matter which client I choose to do the mining? If so, to what end?


texts:
I was reading this information regarding the MEMPOOL:
https://coinsutra.com/bitcoin-mempool/

Suppose I have a transaction that contains a certain number of entries (ex: 300). In addition, suppose I have 7 other transactions - each having 50 entries.

Suppose I offer $1 to the miner for each transaction to be processed.

When broadcasting a transaction, it goes to the MEMPOOL first (so that a miner can pick it up for processing)?

It is my understanding that the transaction would not be processed immediately because the fee is too low.

If that is the case, then can one have a bitcoind server of their own, pull out the transaction, process it (or the entries in it) and then create a block to be added to the blockchain?


texts: How can i create an Anyone can spend output?

texts:
How can i create an Anyone can spend transaction using p2pkh outputs?

Also how would such a transaction in hex look like?


texts:
How to get hash160 address in string using bitcoinj ,I tried the following code

NetworkParameters params = TestNet3Params.get();
String ads = "n1XZMMm3ikh97Mr8JVnnahfugad2DRcVrB";
Address address = new Address(params, ads);
byte[] adshas160 = address.getHash160();
System.out.println(adshas160);

all I'm getting is [B@4c762604


texts: Where can I find a step by step tutorial on how to setup primeminer and join a pool?

texts:
I'm new to Primeminer and couldn't find a tutorial on how to set it up. I have downloaded the Primeminer software and it seems to consist of only two files:

a .bat file
an .exe file.

Is that all there is?

Is primeminer universal for all cpu mining coins?

If you run primeminer and it connects to some pool, would the pool then send data back to your miner app, in order to crunch the data and send it back?


texts: How are transactions propagated through the bitcoin network? (In-depth)

texts:
I know the general gossip protocol that occurs i.e transactions are sent to neighboring nodes who then send it to their peers etc. but I was trying to find a more in-depth answer on how transactions are sent across the bitcoin network.

I read briefly in a paper that there is some sort of transaction queue that the node keeps for each neighbor and that they will only select a random (?) amount of those transactions and send in an INV message to those nodes.

Why don't they send them all the transactions in the queue and why does it wait a random amount of time to send the transactions in the queue?

Any help would be great, thanks!


texts: How does Ripple solve the sock-puppet problem during consensus?

texts:
I'm under the impression that Ripple uses a consensus based system in order to determine which of two payments is the authoritative one, with the other getting rejected due to a lack of proponents. This form of decision making appears to be prone to a sock-puppet attack.

Would it be possible for someone to create a high value spend in one store and then negate it through a carefully timed sock-puppet attack such that the original   spend is outvoted by a lesser value payment that has vastly more (fake) backing?

In short, how are resources consumed during the consensus process?


texts: Can I use bitcoin USB block erupters to mine litecoin?

texts:
Let's say I buy a USB block erupter, can I use the same to mine Litecoins?

Does it require special software and setup to mine Litecoins?


texts: What is the different between Open Transactions and Ripple?

texts:
I have been watching the Open Transactions project. Since Ripple has recently came up I am curious as to their relation to each other and if they are trying to achieve the same thing but with a different framework.

At first glance they do appear to be doing the same thing (I think) but what are the differences?


texts: Is there a chart of all combined orderbooks?

texts: I would like to view a chart where all bid/asks are combined from the various exchanges, instead of keeping multiple tabs open for each exchange. Is there a website that allows this kind of meta-overview?


texts: Bitcoin core - creating transaction from UI without broadcasting it

texts:
I would like to use Bitcoin core's wallet UI to create a transaction but instead of broadcasting it I would like to get the underlying raw transaction.

Is there a way to do that?

I assume that network sniffing tools might be able to help but I wonder if there is a direct way. I think it would be really useful to have such feature - view raw transaction & confirm before broadcast.

The motivation for this specific scenario is the following  - I would like to create a raw transaction on an offline machine running Bitcoin core (with synced blockhain) and broadcast the transaction from another machine.

I am aware that what I am asking for is easily achievable with the CLI but I'd like to use the convenience of a GUI (& fee calculations) and also avoid creating non-intended transactions.


texts: How can an encrypted wallet spend coins without asking for decryption password?

texts:
It is possible for some encrypted wallet to spend coins (e.g. this one) without requesting a decryption password or any other form a authentication. Of course, a password is requested when first importing the wallet file, but nothing after that. This seemingly means that a simple user process has access to my private keys. What prevents another process from replicating the same code and reading the same files so as to spend my coins? There appears to be a major vulnerability, which I am guessing is not real. What cryptographic trick is in play here, to allow such wallet behavior without exposing the user's private keys?

EDIT The answer to the paradox stems from the fact that access to the file system on Android does not work in the same way as on a typical Linux distribution. A file owned by an app cannot be accessed by another app (unless the other app is root). This allows the Android wallet to decrypt the private keys (with password) when restoring a backup file, and save the unencrypted keys to a new file without compromising security. So it is possible for the wallet to spend coins without referring to the backup file again (which would require a password) and simply look for the private keys in the newly created file (which requires no password). (The Answer is due to Nick ODell and Andreas Schildbach, as can be seen from the comments of this thread).


texts: Will my bitcoin be there after syncronising  Am trying to sweep from my syncronising bitcoin core using my private key but its showing no output whats going on


texts: Trying to connect to bitcoin core on Google Compute Engine from an external IP, I was getting "couldn't connect to host error"

texts:
I have having issue connecting my bitcoincore from an external ip address (Hostgator to be specific). The Bitcoin core is hosted on Google Compute Engine (Windows Sever 2012).

Here is what i have done

Bitcoin Core Config File

deprecatedrpc=1
dbcache=1000
txindex=1
server=1
rpcuser=myusername
rpcpassword=mypassword
rpcport=8332
rpcallowip = 192.185.35.200

N.B 192.185.35.200 is the dedicated server IP on Hostgator.
N.B 35.195.0.35 is the Ip for my VM on Google Compute Engine

I also disabled firewall totally on the windows machine

I specified compute engine firewall rule to allow access for TCP port 8332 and 8333

I contacted hostgator, they told me port 8332 is enabled for outgoing connections but not for incoming on shared server

https://www.yougetsignal.com/tools/open-ports/ shows the 2 port as opened

But still, i can't get JSONRPC to talk to the bitcoincore. What i am getting is "Could't connect to host" .  When i make a call to with the EasyBitcoin Library.

<?php

include('easybitcoin.php');

$bitcoin = new Bitcoin('myusername','mypassword','35.195.0.35','8332');

$info = $bitcoin->getinfo();

print_r($info);

?>

What am i missing


texts: How would an artist be able to sell their own music for Bitcoin?

texts: What options are there for artists to market their Music in exchange for Bitcoin? How would an artist be able to directly sell his work to his fans?


texts: Does Bitcoin-QT use more CPU when its idle than during synchronization?

texts:
I am running the standard client on a micro Amazon EC2 instance. When I am synchronising Bitcoin with the network, it uses about 50% of the available CPU. After it is fully synchronised, I leave it alone and it cranks up to 100% by itself.

What can be causing the standard client to behave in this manner? Is it due to possibly high transaction volume, sharing information with peers, or perhaps something else?


texts: Hi. Today I tried to sent coins to Mostyn Lewis Investment. But I sent it somewhere else?Where?

texts: And here I sent it.Could you help me please. This is the adres I have sent it to;bc1qtpqqawlvye7elp3sp3snmfts7lfkqtduefe8jq so I do not know where I can find help.And where the money are sent to. I wanted to send it to Mostyn Lewis Investment. But it showed me from coinbasewallet that I do not have enough. Then I put all I had. And also checked it in blockchain explorer. A lot of confirmation and still confirming..where was this sent to?(back to me or I lost it) And I really do not know. If sb knows the answer even is bad, please answer me...Thanks


texts: I've seen a transaction with 24 ancestors in the mempool, Is there a sensible use of this?

texts:
I've seen a transaction with 24 ancestors in thee mempool, Is there a sensible use of this? Or is a kind of spam or something else?

It got mined on block 613101

$ getmempoolentry 132c52367b5e8c6abe87eee8bc60032c58f3d1296b8ca216373d924d94013d45

{
  "fees": {
    "base": 0.00000202,
    "modified": 0.00000202,
    "ancestor": 0.00019743,
    "descendant": 0.00000202
  },
  "size": 202,
  "fee": 0.00000202,
  "modifiedfee": 0.00000202,
  "time": 1579178958,
  "height": 613089,
  "descendantcount": 1,
  "descendantsize": 202,
  "descendantfees": 202,
>  "ancestorcount": 24,
  "ancestorsize": 4848,
  "ancestorfees": 19743,
  "wtxid": "34799217c58ef6da2417db2cc7ddf0715f9d0ab86926b3fd99e23e1ce92968c4",
  "depends": [
    "676a48b91e030f2d757b9ae877d452b0d88a3304d19f0960d988d69fc9c180f2"
  ],
  "spentby": [
  ],
  "bip125-replaceable": false
}


texts: How good a "take off" on the block chain is Factom?

texts:
An advertisement for Factom says that it improves on "speed, cost, and bloat." And it apparently provides a decent "proof of existence" for people who want to "copyright" their work.

What is it that Factom can and cannot do, especially with reference with the original block chain? Put another way, what are its advantages and disadvantages?


texts:
Is there a way to boost propagation?
E.g if someone sent me an amount, he says that he sees the txid in blockchain because he is connected to faster nodes, and I search this txid and I see it doesn't exist, because I'm connected to slower nodes.
Is there a way that I will be connected to faster nodes? So I won't need to wait a few seconds/minutes to receive the data because I have slower nodes.


texts:
I have a very simple question, but didn't find a answer with google.

When i backup only my private key, it is possible to restore my addresses with bitcoins on it?

Example: I have generated 1.000 address not in the Client. Then some one sent 3 BTC to one of these addresses. Get the Bitcoin-Client the address with the 3 BTC automatically or only when i import the address?


texts: What is the chance of transactions being processed in different order that they are broadcast

texts: Given I want to transfer bitcoin from A to B, and then from B to C. I broadcast two transactions to the network (with the same transaction fee), in order: A to B and then B to C. Is there any chance that the second transaction gets processed before the first (and thus rendered invalid because the bitcoin has not yet arrived in B)?


texts: Specifically, I need the easiest possible way to store Namecoins mined through merged mining, so the eWallet will have to deal well with generated transactions. Do any NMC eWallets actually exist? Do any of the exchanges deal well with generated transactions at receiving addresses?


texts: In the simplest way possible, describe how the 21 Million limitation is enforced to a non techie

texts:
In this Bloomberg video: Gold for Nerds , they ask

  How is the limitation of 21 million Bitcoins enforced?

Though I am very familiar with the technical reasons why and how it's done I haven't seen an explanation suitable for a non-techie.

Question

In the simplest way possible

Can someone describe what is the Ecludian Constraint is?
Can someone explain the enforcement of the 21 Million limitation like I'm Tom Keene?


texts: Why do small transactions without fees ever get processed?

texts:
I understand that adding a small transaction fee as incentive ensures block generators will include your transaction.

When you have no transaction fee, what is their motivation then?
Why do some people include it and some don't?
I have read many accounts stating that small transactions are less likely to be included - so is a big (in terms of amount of bitcoin) transaction with no fees more likely to be included, and if so, why?


texts: can i update my bitcoin qt 0.7 to 0.11 if my wallet has never synchronised and i'm still waiting to receive my bitcoins

texts: can some one please give me some solid advice as i am in need of my coins and it seems this is the best way to retrieve my coins but i cant risk losing my bitcoins! i have tried to create a raw transaction to my new multibit HD but cant get the command right!!!! as my IT literate nephew said that is an advanced way to go about it specialy since i know FA about IT work! lol. apparently updating my wallet can solve the slow synchronization. i have version 0.7 but wish to update to 0.11 or 0.10. will this work? how do i go about it? is there a high risk of losing my bitcoins? cheers :-)


texts:
I know that the deriving path for Bech32 is 84, but what about P2WSH addresses path is it the same?

I've been reading https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki but nothing on there.

For example, I'm using path 84 to derive P2WSH addresses, but electrum uses that path to derive P2WPKH addresses. I would like to know the correct path that I should use, so my mnemonic phrase becomes compatible with other platforms. Something like 44 and 49 paths.


texts:
I called bitcoind getwork slightly earlier in the day and this is what I got:

{
    "midstate" : "6d8b2d759123e7311c552f0c99f6d520378062ac7a14fb11f6d433779d282faf",
    "data" : "00000002c2bf65e9637a1c11955c2ba1c45c9bffad322d4fa0d9529e0000014300000000e9587c30863f5f410ea9d0611d3da6b7d0afd390b4b8e33cd71297c9d20dc74651ad7ea71a01616400000000000000800000000000000000000000000000000000000000000000000000000000000000000000000000000080020000",
    "hash1" : "00000000000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000010000",
    "target" : "0000000000000000000000000000000000000000000000646101000000000000"
}

So for the time being lets throw away the midstate which I will not be using since I am only trying to understand.
So now doing the 32 bit byteswap on the data I get this:

Data
02000000 e965bfc2111c7a63a12b5c95ff9b5cc4 4f2d32ad9e52d9a04301000000000000 307c58e9415f3f8661d0a90eb7a63d1d90d3afd03ce3b8b4c99712d746c70dd2 a77ead51 6461011a 00000000

Now I am unable to figure out how to actually read this information. According to the wiki, the first 4 bytes are version. Here the first 4 bytes are version.

Version:
02000000

Isnt it supposed to be 2. The above is a really large number in big endian.

Now the previuos hash block:

Hash:
e965bfc2111c7a63a12b5c95ff9b5cc44f2d32ad9e52d9a04301000000000000

I am unable to find this hash anywhere on blockexplorer or block chain info? I tried to change the endianess once again but to no avail.

Finally I left the merkle root out and tried to confirm with the utc time:

Time:
a77ead51

Which corresponds to the year 2081. What exactly am I doing wrong here?


texts: My understanding is that all cryptocurrencies(including bitcoin) have a public/private key pair that is needed to perform transactions. I am curious how exchanges program these wallets and generate the keypair for all the cryptocurrencies. I assumed there would be a wallet SDK for each cryptocurrency so that developers could program their own wallets, but did not find any such thing. Also, how do they programmatically submit transactions to the network? I assume you need to provide some IP, but since this is a decentralized network what IP would you provide?


texts: address format is different from bitcoin core response from btcd

texts:
For now, I'm generating WIF and address using golang btcutil package programmatically.

    wif, err := btcutil.NewWIF(privateKey, conf, false)
    if err != nil {
        return nil, err
    }
    strPrivateKey := wif.String()

    // Address
    address, err := child.Address(conf)

    walletKeys[i] = WalletKey{WIF: strPrivateKey, Address: address.String(), EncodedAddress: address.EncodeAddress()}

After generating wif, I import this wif using bitcoin client importprivkey

err := b.client.ImportPrivKeyRescan(privKeyWIF, label, false)

And then, I make sure this private key is added into wallet using getaddressesbyaccount "label" command.

Somehow listed address and first generated address seems different.

I'd like to know why it's different.

Thanks in advance.


texts: What is the genesis block? In which ways is it important or different from other blocks?


texts:
I have recovered my wallet from an old data file using Bitcoin Core. The wallet has synchronized without issues. I have tried to send BTC to at least two exchanges and neither transaction has completed. After the first transaction (going to the Coinbase Wallet) I waited 10 days and then tried increasing the transaction fee - no change. The returned stats code says "Status: 0/unconfirmed, not in memory pool, abandoned."
I then cancelled that send and tried sending to Kraken and it's still processing after six days. The status code for this one says "Status: 0/unconfirmed, not in memory pool?
Any ideas? Am I just SOL?


texts: What does postfic in the wallet transaction id mean

texts:
It's known the txid is always a 32 byte hex sequence for example ceca9c54d1a2f9122326a871a3b0b20b725540137e80cb50da663a404f7849a8, but when inpecting the transaction in a wallet it shows it with a dash and three number postfix :

What does -000 mean in the txid, and why is it there?


texts: Where can I turn the unique hash result of SHA256 to bitcoin?

texts:
i watched on youtube from 3Brown1Blue channel about "how bitcoin works", it said what makes bitcoin valued is come from the unique hash result of SHA256. for example if someone put string to an argumen function SHA256 like SHA256("Hello World!") and consider the result of hash 000006d40bf420404a011733cfb7b190d62c65bf0bcda32b57b277d9ad9f146e, there's 5 zeros at first which we can say unique result. Then that's result make bitcoin valuable.
Now what if I found another unique result hash of SHA256 with just SHA256 encryptor online manually? How to add it to blockchain so my identity is approved by blockchain watcher that I have it value and how do I get the reward from it?


texts: aggregated signatures for combining payments over a low bandwidth mesh network

texts:
Background

I'm researching how in a low bandwidth mesh network payment transactions from nodes can be combined to reduce the bandwidth used for payments.  Aggregated signatures seem like a useful technology to reduce the size of transactions between nodes involved in a message relay circuit.

I believe it's important to focus on the signatures because unlike the payment addresseses in a transaction, signatures cannot be compressed by using a lookup table of their hash and/or an HD wallet path.

Greg Maxwell's write up on aggregated signatures mentions a scheme using Schnorr signatures and two other schemes, one way aggregated signatures (OWAS) and Boneh–Lynn–Shacham (BLS) signature aggregation.

Question

Which signature aggregation approach, if any, do you think is best suited for building up a payment transaction where each node in a chain pays the next node some small amount?

To try and make my question more concrete, a simplified protocol might look like:

1) Node A broadcasts a transaction tx_A that has two outputs: one spends some value to any address and one spends the change back to an address node A controls.

2) Node B receives tx_A, and broadcasts a tx_B that spends the unspent value from tx_A to an address node B controls, and spends from that address (less some fee they keep) to any address.  Node B creates a signature for tx_B that aggregates the spending signature from tx_A.

3) Node C receives tx_B and does the same as in step 2 to produce tx_C.  This continues until the message is received by the message destination node F, or there is no more unspent value left.

4) The final tx_E should have an aggregated signature that spends from addresses controlled by nodes A..E to pay nodes B..F.

Key requirements are:

non-interactive (or only interactive with the next node in the chain)
aggregating many signatures does not increase the transaction size

Thanks in advance and sorry if my question is not clear.  I've had trouble digesting the primary source material and hope what I'm asking isn't too crazy.


texts: Are you able to relocate your node's physical location (i.e., move from Oregon to New York) and keep all the channels you've established intact?


texts:
I have made an altcoin in my local machine running MacOSX. I have purchased amazon ec2 and compiling the daemon to running in unix.

How do i add seed nodes?

I see that there are two files chainparams.cpp and chainparamseeds.h.
What is the difference between these two files?

chainparams.cpp

vSeeds.emplace_back("dnsseed.thrasher.io", true);
vSeeds.emplace_back("dnsseed.litecointools.com", true);
vSeeds.emplace_back("dnsseed.litecoinpool.org", true);
vSeeds.emplace_back("dnsseed.koin-project.com", false);

chainparamseeds.h

static SeedSpec6 pnSeed6_main[] = {
 {{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xff,0xff,0x05,0x53,0x80,0xc7}, 9333},
    {{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xff,0xff,0x05,0xa4,0xdf,0x66}, 9333},
    {{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xff,0xff,0x05,0xff,0x56,0x07}, 9333},
    {{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xff,0xff,0x0e,0x98,0x79,0x2d}, 9333},
    {{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xff,0xff,0x0e,0xa2,0xd0,0x9d}, 9333}


texts: Does an OP_RETURN script always need another output within the transaction?

texts:
I was reading this:
Explanation of what an OP_RETURN transaction looks like
and I wondered if the second output "value" : 0.00200000, was at all necessary. Can I just have a OP_RETURN with a 0 output in the transaction?


texts: Network of 3rd-parties to monitor for Lightning Network theft transactions

texts:
Whenever the balance of a Lightning channel is updated, the counterparties must revoke the Commitment Transaction reflecting the channel's earlier balance, and sign a new Commitment Transaction with the new balance.  If the counterparty attempts to steal funds by broadcasting the revoked transaction to the Bitcoin network, then the other party can broadcast an anti-theft transaction that forfeit's the counterparty's funds.

A common objection I hear from skeptics of the Lightning Network is that, as a consequence of this, you have to be constantly online and monitoring the blockchain to prevent this kind of fraud.

However, as mentioned in this post, I've heard it proposed a number of times that:

  the anti-cheat transactions can be safely distributed in the network
  and have an attached bounty to make it interesting for third parties
  to monitor on your behalf. When a third party broadcasts the
  anti-cheat they'd assign the bounty to themselves, but would be unable
  to touch the remaining funds.

My question is, has this ability to broadcast anti-theft transactions to third-parties interested in monitoring the blockchain for theft transactions actually been implemented somehow?  Do the existing Lightning implementations include a protocol for broadcasting anti-theft transactions to third-parties?


texts: Can I cancel a transaction that has no confirmations due to low satoshis?

texts: Hi all I changed the cost to transact from $24 us to $1.40 when I transferred my bitcoin funds and no one will confirm it. Is there anyway to cancel it? I can't do a double transaction because I was moving my entire wallet off my ledger Nano to GDAX


texts:
Sorry, if the question may seem trivial but it is bothering me for a while now. I understood how the proof of concept works when one tries to change an old block. But how that will work for the case of the latest block?

For example, say I am an attacker who continuously mines blocks. Every time when I get a request for a new block, I will add a fraudulent transaction to it even before trying to find the hash. And I do that every time I get a request for a new block. If I was not able to successfully find a new block before someone it's okay, I will just discard my current work on the fraudulent block, will accept the honest block and again will repeat the same with the new block.

After a while, I ought to be lucky and my fraudulent block will be the first one that is published into the network. When that happens my block will be part of the honest chain and there will be no way to find out about this.

How Blockchain prevents this kind of attack?


texts: Blockchain.info keeps sending wallet backups

texts:
Blockchain.info is sending my wallet backups over and over again;
is this someone trying to hack my wallet or something else?

I haven't done anything on my account, no settings changed et cetera.


texts: I have a paper wallet as an image file, the QR code of the private key gives a base64 encoded string which gives "Salted_(some binary here)" when decoded. What format is this and can I get the private key without a webcam or phone?


texts: Where is the best information about the contents of bitcoind 0.8.2?

texts:
There seem to be a few interesting changes in this version, possibly affecting the protocol itself (de facto).

Where can I find the most relevant, concise yet detailed information about this version?


texts: use block chain without using bitcoin based payment

texts:
I am beginner to bitcoin.
I intend to develop a proprietary mobile app to trade some kind of commodity among multiple users( with a optional arbitrator in between but not a must).

I got interested in bitcoin technology since it offers the block chain with hashing and signature to establish distributed ledgers. I want to track the app transaction between multiple users by leveraging the block chain and hashing mechanism of blocks. I will customize the contents of blocks with my proprietary stuff.

I do not want to use bitcoin method of payment for my mobile application transaction. This will eliminate the need of mining and maintain a bitcoin wallet. Users can use any kind of payment outside bitcoins

Is this possible? How can I leverage appropriate components of bitcoin open source API and which one should I use?


texts:
I goal is to understand. I do not want to earn money with mining.
(I have a server without GPU)

Here is what i've done:

I have downloaded, maked and installed bitcoin sourcecode from github.

It seems to work because i can interact with bitcoind with bitcoin-cli command.

I know this is not a good practice but i want to "see" my private key.

I have read several documentation and tutorials and they said i need to generate an address first, then call dumpprivkey method.

Like this:

$ bitcoin-cli getnewaddress
xxxxxxx

$ bitcoin-cli dumpprivkey xxxxxxx

I do not understand but if i repeat twice this operation, i get 2 differents private keys.

So this is not the private key i am looking for... What is those privates keys ?

Thanks


texts: What is the strategy mining pool servers use (regarding difficulty)?

texts:
If I understand correctly mining pool servers give miners target thresholds of lower difficulty so each miner can mine a number of 'block solutions', called shares.

For example if threshold is  0000 1000, mining pool can give each user the threshold 0100 0000, with 1000 times lower difficulty. Then every cca 1000 mined shares will give one actual mined block.

The actual target threshold in the block header stays as original as having lower difficulty in block header would invalidate original block hash and lower target threshold is communicated separately?

Is each miner given the same difficulty?

Is client's hashing power taken into account when assigning work?


texts: Litecoin-qt getblocktemplate ￼Support for 'segwit' rule requires explicit client support (code -8)

texts:
I have downloaded the Windows version litecoin client from https://litecoin.org/. I am trying to setup CoiniumServ to serve as a LiteCoin Pool.

Most configuration are done.
However, I am facing this issue. When I try to query getblocktemplate from the litecoin-cli, I will get this error Support for 'segwit' rule requires explicit client support (code -8).

Can anyone help ?
Thanks in advance!


texts: Is it secure to put a wallet address on one's business cards as a QR code?

texts: As a company, we're making business cards, and would like to put our bitcoin addresses on our business cards as QR codes. Yet, I know that it is a best practice for wallets to cycle addresses - I mean, after an address is used, then create another one. So, is it safe to put wallet address QR codes on multiple business cards and distribute them, and are there best practices for doing so? What security benefits does one lose by distributing the same receiving address to all clients and associates, or would it be wiser to pre-generate a few dozen each time we generate our QR codes to print business cards, so that they can all be unique? Would that even be possible, without using each one once before the next is generated?


texts: Linking Bitcoin addresses based on a private key - is that possible

texts:
I have seen a claim as follows:

  [We] apply algorithms to detect which bitcoin addresses are sharing the same private keys. In most cases, this leads to a high-level assertion of certain addresses to be owned and controlled by a single party

is that possible?

What I'm thinking is one private key per one public key
As far as i understand, HD wallets use a seed to create many private/public key pairs, but no two public key shares the same private keys.

Any pointers would be appreciated.


texts:
On my node's https://getaddr.bitnodes.io/ page, clicking the "Check Node" button on the bottom of the page reports that the node associated with this IP address is up; however, at the top of the page, "Node Status" says it isn't. It seems my node is having discoverability issues with the Bitcoin network, although https://getaddr.bitnodes.io/ can ping it just fine.

Why would this be?

I've even run the node on a different network (one even supporting IPv6), and I get the same issue.

I'm thinking it may have something to do with my running bitcoin-qt with a Tor proxy, although I am explicitly supplying the "--listen" flag to bitcoin-qt.

(I've asked about this on Github, but it doesn't seem to be a big in bitnodes but a configuration issue on my end; or perhaps the BTC network in my area just doesn't have need of more nodes?)


texts:
I read this comment:

  You could consider running a pruning node, which is practically the
  same as a full node (including security), except it throws away some
  of the old history. Version 0.11 will make that possible

But I can't find details of how to run bitcoind in pruning mode. Questions on this site seem not to be recent enough to yield answers, and I also don't see a pruning mode in the bitcoind parameters.

Any insights into this?


texts: Lightning network Fraudulent Channel Close

texts: If a lightning network transaction between 2 participants, where the payment is routed by multiple channels, does it means that all full LN nodes that routed the payment should stay online to avoid Fraudulent Channel Close ?


texts: How to reach out the trader through the bitcoin address?

texts:
I am actually a person who keenly watching and wondering the growth of bitcoin in recent days, when I was looking for an alternative business plan one of an Instagrammer pinged me and checked my interest in doing forex trading, we used to communicate through WA, her number is given below
Though I had no prior experience she was ready to help me in forex trading,
Initially, Invested 200$ followed her instructions, my trade account has been created in "https://en.cryptsmarket247.com/public/" and my bitcoin wallet has been created in "Wazirx". not sure it was a scam but my trade account reached $780, and still it is showing the figure and unable to withdraw.
She was claiming that my account reached $10000k and I need to pay $250 as a migration fee to withdraw the money, I paid $250, and once paid she started telling me that the money has not reflected on her company account. I was asked to pay one more $250 not to lose the already paid $250 and the profit $10k.
As I was new to trade and bitcoin I trusted her and paid another $250. she told me I would be receiving $250 in 30 mins $10k in 3 days and left as usual, but, from today onwards I could not see her in WA.
I could see where the bitcoin deposited at her end but not able to do anything, I raised a complaint with FTC and reported the issue at "https://bitcoinwhoswho.com/", is there any way I could recover my money back or I could reach her with the below details?
Her mobile number
Mobile number : +1 (819) 800-6746, +1 (364) 202-6061
Bitcoin Address: 3R2XQzyAqbzCmAsDX4tEjX5bm3SmusKym2
Her image attached (she claimed that she is the one in the image)

I am sure she is not a techie, so there any way I could block her bitcoin address?
any idea on the website I have given "https://en.cryptsmarket247.com/"
Someone, please help me!
Regards,
Raaamuz


texts: Energy to confirm one block with state-of-the-art hardware at current difficulty level

texts:
An earlier answer claims it would burn around $2M worth of electricity to confirm one block using an ordinary CPU.  See:
Energy to confirm one block?
Can anyone estimate what this figure would be for today's state-of-the-art mining hardware?

E.g., suppose I am presented with a chain of 8 block headers with mining difficulty at or above current level.  Without any other information, how certain could I be that they were generated by current blockchain network?  How much would it cost to create a fake, ignoring equipment cost?


texts: How to test if a transaction can spend an existing output?

texts:
Suppose I'm writing a transaction by hand, that spends an existing uspent output sent by myself from another address. Is there a way to test if the transaction can really spend that output, before brodcasting? The reason is, I want to be sure if I'm correctly generating the sigScript.

EDIT: I know it is possible to syntactically verify transactions, but I'm asking if do exists a method such as canSpend(myTransaction, unspentOutput). Ideally that would execute the combination of scripts myTransaction.sigScript and unspentOutput.ScriptPubKey and check if the result is true.


texts:
What is the function of Gas Limit parameter in Ethereum?
Is it involved in mining or something else?


texts:
I'm running the generate command on a bitcoin core fork (with difficulty = 1) and bitcoind running in another window and outputting the best/vs. hashes as it should when generate is running.

However, nothing has been mined yet; generate keeps returning empty brackets. A similar command worked on this machine so I know its powerful enough to mine at this low difficulty.

How do I check what's going wrong? Perhaps a verbose option for generate or something other than debug.log (this just outputs keypool return/keypool reserve throughout. I have also tried to mine in the debug console of QT client but with no luck either.


texts: How to fork Bitcoin and build own cryptocurrency

texts: Is there any step-by-step tutorial about how to build own cryptocurrency based on Bitcoin code?


texts:
I'm in the process of assembling raw transactions and I have a couple of questions.

I'm using listunspent to get a list of the transactions I can spend....

First, should I select the oldest transaction first for inclusion? Or is there a better way to select transactions?

Second, for calculating the transaction fee, is there an easy way to estimate the size of a transaction? For example, can I say each output is X bytes and each input is Y bytes?


texts: If the computer that stores the bitcoin is destroyed, how does someone access their bitcoin?

texts:
I have seen people say that you just need the private key and "some software" to recover your bitcoin. What does this actually mean in the real world? Can someone give an example?
Also, if you are using some company's wallet to store the bitcoin, you are relying on that company's computer for storage. How would you get the bitcoin to be stored on your own computer?
I am sorry if these are poor questions; I am finding it difficult to wrap my head around the actual storage of bitcoin.


texts:
I sent .67 BCC to a BTC address on Litebit 13 days ago. The address is showing the amount of cryptocurrency and it is showing as verified.

They state on one of their webpages that unless the total is above 2000 euros and reported within 8 days they won't move. Is there a genuine reason for this or are they just casually admitting to stealing all incorrectly sent cryptocurrency under this amount? How hard can it be?

"Recovering cryptocurrency cross chain is an inherently dangerous and time-consuming process"


texts: How do new Cryptocurrencies prevent a 51% attack?

texts:
I've seen similar questions, but not specifically in reference to new altcoins.

When a new cryptocurrency is released, the developer(s) have limited amounts of resources. What prevents a group from carrying out a 51% attack while the mining network is still small?

I realize there isn't likely any benefit to the group carrying out the attack, since coin value will subsequently be lost, so the motivation would probably be carnage or the desire of eliminating a rival coin.


texts: How does the receiver of a transaction check the whole chain of ownership?

texts:
While reading Satoshi Nakamoto's paper on how bitcoin works, I got stuck on #2. In a chain of transactions, how can someone who has received the coin check the whole chain with just a signed hash of the previous one?

Either

The person sending the coin would have to include the whole ownership chain, which would start increasing more and more in size
There would have to be a public hash-to-transaction mapping somewhere.
There would have to be a list of valid coins somewhere, making checking only the most recent transaction necessary

I don't see Satoshi Nakamoto talking about any of these.


texts: How do you apply “-zapwallettxes” for multbit 0.5.15

texts:
I made a transaction a few months ago but the transaction is still not confirmed, the Bitcoins are debited from my account and the balance in my wallet is zero.

Information on the transaction

The transaction is seen by 1 peer and the status of this transaction is still unconfirmed.

I guess it is a bit of the same issue as described in this question: How do you apply "-zapwallettxes" on Windows?

Though I use the wallet MultiBit 0.5.15, the commands like -zapwallettxes does not work in my case.

Does anyone know how to restore this transaction, or what commands I should enter in cmd to fix this?


texts: Building blockchain on macOS Sierra (10.12)

texts: I am trying to build a bitcoind client or similar program on my macbook so that I can access the blockchain information for analytics purposes. Honestly, I dont have the slightest clue how-to do this though. Can someone please explain? Or better yet, is their a simpler way to view the up-to-date blockchain information that I am unaware of?


texts:
In his recent talk, Andreas Antonopoulos said "By probably the end of 2016, Bitcoin will have a hybrid proof-of-work/proof-of-stake system." and then continues to label the Lightning network as a POS system.

Is the Lightning network a proof-of-stake system?


texts: Where can I see the current size of the bitcoin blockchain?

texts:
I am tying to understand the concept of the bitcoin blockchain, from what I understand everybody owns a full copy of the bitcoin blockchain, but is it possible to see the current size somewhere without having "checked it out/cloned it"?

And are there any backups being made? I know it's distributed and everyone owns a full copy - kinda like with a git repository - but is it also backed up on centralized servers?


texts:
Do you have any ideas or suggestions how to visualize Merkle trees?

For our open source project "Open Tracking" we create Merkle trees for thousands of tracking counters before putting the root hash to a bitcoin transaction with OP_RETURN script.

Each hour we merklize state of all active counters for ~20,000 domains and thus we have the tree with 20k elements at the base level.

My first idea was to visualize it in spreadsheet-style. A first column will be level one, a second column will be level two etc.


texts: How can one create a Genesis Block for a new Proof of Stake Cryptocurrency?

texts: I've been trying to fork the cryptocurrency Clams for about a week now. All of my code is correct to the coin's specifications, but I've been stuck on the creation of the blockchain. The developers have removed the code involving the genesis block and there doesn't seem to be any way for me to generate the PoS genesis block. If anyone has any experience with PoS coins, I would appreciate any advice incredibly. Thank you.


texts: Recommended bitcoin wallet for beginner?

texts:
I use Windows, Android, Chrome - what wallet would be best and safest for beginner?

I would like it to run on both Windows and Android.

Thank you.


texts: Multibit - error (or at least confusion) in 'How to check digital signatures" info for noobs

texts:
This may seem trivial, but for someone who knows little about this lebvel of security and wanting to really get it right first time, I found it quite offputting ... whereas the suggested process should be confidence-building, no?

============================================

URL:  https://multibit.org/blog/2013/07/24/how-to-check-signatures.html

============================================

quoting:

Step 1 - SHA1 in action

The first step on the road to security is access to strong cryptography. We'll start by creating a simple one line text file:

$ echo "Hello world" > example.txt

The above has an expected SHA1 hash of 33ab5639bfd8e7b95eb1d8d0b87781d4ffea4d5d which we will now attempt to verify. Depending on your operating system you'll need to install a few applications in a particular order to establish a solid trust foundation.
Windows - install FCIV

Microsoft's File Checksum Integrity Verifier (FCIV) is a command line tool that provides access to SHA1 checksums.

Once installed, you can test it out on your example file as follows

  fciv.exe -sha1 example.txt

==================================

It was not clear to me precisely what the 'example.txt' file should contain.  If I entered the supplied line into a DOS box it didn't seem to work (in terms of creating a text file).  So I decided to create the text file myself..  Reading the line literally the text to include should be:

$ echo "Hello world" > example.txt

or maybe just:
$ echo "Hello world"

or maybe just
Hello world

??  Anyway, I tried loads of options and at no time could I get fciv.exe to generate the given key!!  >8-(

Giving up after 30 mins I tried the quick brown fox test easily found in Wikipedia and it worked first time, so the software is working and it is something to do with the suggested text file.

Sorry if this seems pedantic but if even very simple things don't check out, then it does not help confidence.

Cheers.


texts: Tracking Hash/sec of major pools and individual (solo) miners

texts:
I'd like to get a list of the hash power of the major pools, solo miners, and if applicable undocumented hash networks.  How can I obtain this information?

If this information already exists, how did that site or service collect that information?


texts: Stratum Server Exception "[coin] is not connected"

texts:
When i running 'twistd -ny launcher.tac' i getting the following Exception. The connection okay. Please help me to fix this issue.

2017-01-30 19:33:43,094 INFO bitcoin_rpc # Checking for submitblock
2017-01-30 19:33:43,097 DEBUG bitcoin_rpc # submitblock detected.
017-01-30 19:33:43,097 INFO mining # Found submitblock
2017-01-30 19:33:43,101 ERROR mining # Coind Error: Guncoin is not connected!

Thanks,
Your help will appreciated!


texts: What is stopping me from modifying the mempool of my node (may it be PoS or PoW)?

texts:
I have been trying to wrap my head around some core concepts of how a blockchain works and something has been bothering me for a while.

Let's consider a case where I am running a full node of a blockchain (either PoW or PoS chain). Now I am aware that a transaction relayed to my node is verified before it gets added to my node's mempool and again when it has to be added to a block. Now, let's assume that I am going to be the next block winner (I know that it is highly unpredictable), my question is as simple as, what is stopping me from taking out a transaction from the mempool (preferably one with a high amount), modifying it's vout (for e.g. replacing it with my scriptPubKey and keeping the vin intact), and accepting it in my block?


texts: How do bitcoin merchants know that it was YOU that payed them

texts:
When I try to buy something using bitcoins, how does that merchant know that I have payed them the agreed amount.

In other words, how does the merchant know that I payed for the product, and that they can start shipping the product to me. I thought that bitcoin was anonymous in its transactions


texts: What's a good algorithm for reducing Transaction fees?

texts:
I'm attempting to use the createrawtransaction to manually create my transactions and I want to (obviously) reduce my fees. The complication I'm having is that I want to send ALL of the bitcoins in my wallet to 2 parties. So I know that I can specify the inputs and outputs, but there's that pesky fee concept which makes it difficult to just spend it all.

So if I have 5 inputs and 2 outputs, how would I go about calculating exactly what the fee will be and reducing it?


texts:
What do the classes ChainstateManager, CChainState, CChain and BlockManager do in Bitcoin Core?
Why do CChainState and CChain have a leading 'C', but ChainstateManager and BlockManager don't?
These questions were asked during the May 12th 2021 Bitcoin Core PR review club hosted by John Newbery on a Carl Dong PR to de-globalize ChainstateManager.


texts:
I want to create a bitcoin address which starts with a certain passphrase (1mathias, case insensitive). That idea came from this question, and I quite liked it. After some trouble making the file on my Mac, it finally worked.
mbpssd2:vanitygen-master mathias$ ./vanitygen -i -t 4 1Mathias
WARNING: Built with OpenSSL 0.9.8y 5 Feb 2013
WARNING: Use OpenSSL 1.0.0d+ for best performance
Difficulty: 26838491360
[235.42 Kkey/s][total 2888131518][Prob 10.2%][50% in 18.5h]

It is running for quite some time now, and I want to stop it, and continue with finding an address tomorrow. For what I understand, is 1 in that number addresses that fit my passphrase. So if I would choose '1' as passphrase, there would be 1. The percentage showing in terminal is the current generated (and rejected) addresses, compared to the total amount. So reaching 100% doesn't have anything related to finding an address. I can happen at 0.01%, or at 70% or at 8012%, if you are really unlucky (right?)
From the creator of vanitygen I found the following:

If I stop vanitygen when it reports 60% complete, how do I have it restart where it left off?
You don't need to.  The percentage displayed just shows how probable it is that a match would be found in the session so far.  If it finds your address with 5% on the display, you are extremely lucky.  If it finds your address with 92% on the display, you are unlucky.  If you stop vanitygen with 90% on the display, restart it, and it finds your address with 2% on the display, your first session was unlucky, but your second session was lucky

But that does not make sense. If I reach 100%, I am not completely sure that an address has popped up, fitting my passphrase. Is this correct? If I let the program run, and generate a billion addresses, not stopping when (or if) it hit my passphrase, it is even likely that it finds a correct one in the first thousand, as in the last thousand?
I'm quite sure I am right, but I might be missing something. I tried to bold the two areas where I am not sure of.


texts: What happens if a P2SH redeem script is lost?

texts:
Assume Bob creates a complicated Bitcoin Script and asks Alice to make a payment to a hash of this script. (Using a P2SH transaction)
If Bob loses the script (i.e. the source code of the script), is the payment transaction going to be locked forever?


texts: Should a casino manage its own Bitcoin wallet?

texts:
Let's say I wanted to start an online casino that accepts Bitcoins.

Would it make sense to manage my own Bitcoin wallet for this site? Or would it make sense to just use a third-party service that manages the wallet for me?

What other considerations are there?


texts:
Using latest version of bitcore lib , want to check balance for making tx but once I include

var explorers =require('bitcore-explorers');

after

var bitcore =require('bitcore-lib');

Error: More than one instance of bitcore-lib found. Please make sure to require bitcore-lib and check that submodules do not also include their own bitcore-lib dependency.
at Object.bitcore.versionGuard (/home/ubuntu/node_modules/bitcore-lib/index.js:12:11)
at Object.<anonymous> (/home/ubuntu/node_modules/bitcore-lib/index.js:15:9)
at Module._compile (module.js:652:30)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at Object.<anonymous> (/home/ubuntu/controllers/bitcoinController.js:8:14)
at Module._compile (module.js:652:30)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at module.exports (/home/ubuntu/routes/apiRoutes.js:5:15)
at Object.<anonymous> (/home/ubuntu/api/server.js:13:1)
at Module._compile (module.js:652:30)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)

I had a look at this thread

Bitcore = "Error: More than one instance of bitcore-lib found"

but it does not help .
When I comment out this part

var bitcore =require('bitcore-lib');

explorer seem to be running but the problem is it always returns 0 for all the wallets .
For instance this wallet  has fonds wallet testnet fonds

here is the code

const insight = new explorers.Insight();
insight.getUnspentUtxos('mkFPBvd3jbPYn4223SNTneBWHodziU287G', function(err, utxos) {
    console.log(utxos);
    let balance = 0;
    for (var i = 0; i < utxos.length; i++) {
        balance +=utxos[i]['satoshis'];
    }
    console.log('balance:'+ balance);
});

and response is always  [] , 0

1) How to check balance using bitcore without conflict with bitcore-lib  ?

2) Which is the  "web3" (most commonly  used for ethereum) node js library for bitcoin ?

Thanks a lot !


texts: How to automatically get transaction while sending BTC?

texts:
Here is my SendBTC method. I do not want to pass fundingTransaction variable each time I call this method. Currently, I pass fundingTransaction value by looking up to https://testnet.smartbit.com.au/. I want to get this funding transaction in this method only. How can I do this?
public static bool SendBTC(string secret, string toAddress, decimal amount, string fundingTransaction)
    {
        Network bitcoinNetwork = Network.TestNet;
        var bitcoinPrivateKey = new BitcoinSecret(secret, bitcoinNetwork);
        var address = bitcoinPrivateKey.GetAddress(ScriptPubKeyType.Legacy);

        var client = new QBitNinjaClient(bitcoinNetwork);
        var transactionId = uint256.Parse(fundingTransaction);
        var transactionResponse = client.GetTransaction(transactionId).Result;

        var receivedCoins = transactionResponse.ReceivedCoins;

        OutPoint outPointToSpend = null;
        foreach (var coin in receivedCoins)
        {
            if (coin.TxOut.ScriptPubKey == bitcoinPrivateKey.GetAddress(ScriptPubKeyType.Legacy).ScriptPubKey)
            {
                outPointToSpend = coin.Outpoint;
            }
        }

        var transaction = Transaction.Create(bitcoinNetwork);
        transaction.Inputs.Add(new TxIn()
        {
            PrevOut = outPointToSpend
        });

        var receiverAddress = BitcoinAddress.Create(toAddress, bitcoinNetwork);

        var txOutAmount = new Money(amount, MoneyUnit.BTC);

        var minerFee = new Money(0.0005m, MoneyUnit.BTC);

        var txInAmount = (Money)receivedCoins[(int)outPointToSpend.N].Amount;
        var changeAmount = txInAmount - txOutAmount - minerFee;

        transaction.Outputs.Add(txOutAmount, receiverAddress.ScriptPubKey);
        transaction.Outputs.Add(changeAmount, bitcoinPrivateKey.GetAddress(ScriptPubKeyType.Legacy).ScriptPubKey);

        transaction.Inputs[0].ScriptSig = address.ScriptPubKey;

        transaction.Sign(bitcoinPrivateKey, receivedCoins.ToArray());

        BroadcastResponse broadcastResponse = client.Broadcast(transaction).Result;

        return broadcastResponse.Success;
    }


texts: Help setting up phoenix miner on Ubuntu 12.04 - getting a seg fault

texts:
I'm roughly following this guide. The only big difference is I'm running Ubuntu 12.04 and I used the latest version of the ATI Drivers. (I have the same cards as the guide, 2x HD5830's)

When I try running the miner, I'm getting a seg fault.
Here's the exact command I'm running:

./phoenix.py -u http://mineruser@miner0:password0@mine2.btcguild.com:8332 -k phatk DEVICE=0

I'm not sure if this will help but here is the output from DISPLAY=:0 sudo fglrxinfo

display: :0  screen: 0
OpenGL vendor string: Advanced Micro Devices, Inc.
OpenGL renderer string: ATI Radeon HD 5800 Series
OpenGL version string: 4.2.11627 Compatibility Profile Context

display: :0  screen: 1
OpenGL vendor string: Advanced Micro Devices, Inc.
OpenGL renderer string: ATI Radeon HD 5800 Series
OpenGL version string: 4.2.11627 Compatibility Profile Context


texts: Changing wallet password using double quotation marks turn out to be mysterious (Qtum Core)

texts:
I installed Qtum core in my Ubuntu 16.04 server and generated my wallet, and encrypted it.

For the test purpose, I changed the password using the command like below.

I typed below command to change my password.

  ./qtum-cli walletpassphrasechange "oldpassphrase" "newpassphrase"

Let's say my oldpassphrase is test and my new passphrase is test"

Notice that I type the double quotation mark right after the word test

  ./qtum-cli walletpassphrasechange "test" "test""

This returns below line that asks me to close the double quotation mark.

  >

So I typed " to close it.

Surprisingly, the command line has passed!

I thought the new password would be test" or test""

But they both do not work.

Can anyone guess what the new password might be?


texts: Can an old block be inserted into the blockchain?

texts:
I've been shown how network time is enforced, but I'm still having trouble understanding how a false old block cannot be inserted into the blockchain with the entire chain remined or how a powerful miner cannot remine the entire chain.

Does difficulty prevent this because it would take so long to remine the entire chain, or is there another way that "old blocks" are forbidden?

How are new blocks distinguished from old blocks or new transactions distinguished from old ones?

If blocks older than 2 hours are rejected, how are old blocks never rejected?


texts: Will blockchain.info change my BTC adress each time after i SEND my BTC?

texts:
I would like to know a way to send BTC from 1 wallet but different adress each time. (because of transaction fees i dont want to use few different wallets for this)

Blockchain.info changes your BTC adress after you recieve transaction. Will it do the same after you send a transaction?


texts: Tradehill used to be an important Bitcoin exchange, but it was closed earlier this year due to losing a lot of money to their payment processor. What is the full story behind Tradehill?


texts: Do any pools discriminate against some transactions?

texts: Are there any pools that openly discriminate against some transactions? For example, they only put transactions with a fee in their blocks, thus ignoring all "free" transactions?


texts: Blockchain fees $100 for $1000 !!! Please help

texts:
I have a problem with blockchain.info.

I want to send some Bitcoin but fees are very high, $100 for a $1000 transaction. My wallet balance has a lot of tiny transactions.

I also got this message when trying to make a payment:

  Your wallet needs to consolidate many smaller payments you've received in the past. This requires a relatively high fee in order to be confirmed quickly.

What can I do to have ordinary fees?


texts:
I have a bitcoind and LND server running. I can make RPC calls to bitcoind using curl, like this:

curl http://XXX:YYY@localhost:8332 -H 'content-type:text/plain;' --data-binary '{"jsonrpc":"1.0","id":"curltext","method":"getblockchaininfo","params":[]}'

However I can't find out how to make RPC calls to LND using curl.

My lnd.conf contains a [Bitcoind] section like this:

[Bitcoind]
bitcoind.rpchost=127.0.0.1:8332
bitcoind.rpcuser=XXX
bitcoind.rpcpass=YYY
bitcoind.zmqpubrawblock=127.0.0.1:28332
bitcoind.zmqpubrawtx=127.0.0.1:28333

However, what I'm struggling with is finding out or configuring how to actually connect to LND itself with RPC.

Can't find clear documentation about this. I figured out that apparently I need to use port 10009, but this doesn't work:

curl http://XXX:YYY@localhost:10009 -H 'content-type:text/plain;' --data-binary '{"jsonrpc":"1.0","id":"curltext","method":"getinfo","params":[]}'

(result is empty, no error, nothing)

I guessed perhaps I need to set a separate RPC username and password for LND, but I can't find out how or where, i.e. what the settings are in lnd.conf?

Also, do I have to add a config line to make sure the LND daemon is listening to RPC calls?

Also, do I have to add a config line to make sure the LND daemon is accepting RPC calls from specific IPs? (localhost in this case, or adding external IPs later)


texts: Prepare transaction with multiple recipient

texts:
Do you think it is possible programmatically prepare a Bitcoin transaction that has multiple recipient to send the amount to?
Do you think I can show this trasaction in QR code, so payer can scan it with any of the available wallet app?


texts: My Bitcoin.com wallet is asking for a password to confirm send that was never established. So im screwed or file a class action for this?

texts: Wtf is this. Password was never established so i cant send this or get it back. So who is the dummy(besides me) that creates something with no way to retrieve your funds? This is ridiculous


texts: Does more fees means quicker transaction ?

texts:
lets say hypothetically , two persons having access to same private key. makes a transaction with 1 input and 1 output.

person 1 sets fees = 500 sat/Byte
person 2 sets fees = 10 sat/Byte

case 1 :

both the persons broadcasts transaction  at the exact same time.

Which transaction goes through and which gets marked as double spend ?

case 2:

person 2 (with lower fees) broadcasts at 0 second
while
person 1 (with higher fees) broadcasts at 1 second

Which transaction goes through and which gets marked as double spend ?


texts:
Let's say I sent some BTC to Bob, so I created a transaction (forget about scriptPubKey) since let's say I was able to prove it by executing scriptPubKey. so After I sent BTC to BOB, new transaction's input looks like this:
in: [
  {
     "prev_out": {
        "hash": txId,
        "n": 0
     },
     scriptSig:"3045....e5f5"
  }
],

Now, this scriptSig exists because when other nodes come and see this, they should be able to validate it. Now, all we have here is the signature , public key (mine), txId(output transaction that I used).
How can another Node which got this transaction validate it ?
You might say: he will see signature + public key of yours. so what will it do to validate it ? if you say that it will try to decrypt signature with public key, that's not enough. Because what I could do is encrypt blablabla string my private key and I'd put that signature there.
So I guess, my question relates to: how Node will prove I proved that I had BTC with scriptSig + txId ?


texts: Would bitcoin core work on a big endian system? Or even a system where C++'s `int` is not 32-bit?

texts:
Looking at the source code of bitcoin core, the serialization part, I see that there's no serialization abstraction layer that accounts for a possible different endianness or different binary layouts on different machines.

This is not only for disk serialization, but also for network serialization.
If bitcoin core was used on a big-endian machine, or a machine with int size not equal to 32-bit, it'll fail to connect to the network because all sizes will be incorrectly interpreted and values will be different.

Am I missing something or did I arrive at the correct conclusion?


texts: What happens if I send a Bitcoin to an address no one owns?

texts:
Say I send 1.0 BTC to a Bitcoin address that is valid but has never been used yet.

Does that 1.0 BTC effectively disappear? Or will the transaction fail?
If the transaction succeeds, could someone eventually start using that address and claim that 1.0 BTC?


texts: The blockchain is not designed in a way where you can easily get information correct? You have to know more than python basics and have good programming skills as their seems to be no API, and no methods of just querying the data to get basic stats such as "latest transaction" or "biggest transaction ever"....


texts: How to quickly get the balance of any bitcoin address? (with no third-party API)

texts:
As some people have mentioned (eg. here), the only way to get the balance of an address in bitcoin core was to import it as a watch-only address and rescan the blockchain. Starting with bitcoin core v0.17, we can use the scantxoutset command, however this is quite slow:

> time bitcoin-cli scantxoutset "start" "[\"addr(17Pu3CEx34YX8bpGATq45PfL2fGBCPcr2u)\"]"
{
  "success": true,
  "searched_items": 64162818,
  "unspents": [
    {
      "txid": "9796cee98fa88efcb9fdb954188d276b73d6e76719af6b5470ad23a2f744ecca",
      "vout": 1,
      "scriptPubKey": "76a91446255848182640edff4d178f365d7824513bc28d88ac",
      "desc": "addr(17Pu3CEx34YX8bpGATq45PfL2fGBCPcr2u)#x2q6xgrk",
      "amount": 0.02155141,
      "height": 607852
    }
  ],
  "total_amount": 0.02155141
}

real    0m42.419s
user    0m0.007s
sys 0m0.003s

42 seconds is quite slow, I would like to get something comparable to block explorers (less than 2 seconds). Is it possible to achieve faster results with some advanced bitcoin core configuration?

Or, is there any open-source project I could use to index the UTXO set by address? Not sure if libbitcoin, bitcoinj, bitcoinJS, etc. are able to do this faster. Some tool block explorers might use to provide this service would be what I am looking for.


texts:
Following up from my previous question, I still have some questions left.

Does it really work if I turn off the internet before doing getnewaddress? Will it really give me something real and can get the private key while the  offline?

Because for example, bitaddress provides a fake address and private key key if I use it offline when it fails to send the private key to the website owner's database.

Do you think that Bitcoin Core will work offline ? If so will the info be real 100% and valid, or may find out i got fuc**d up after trying to use the address in years to get the btc i sent to it?

As i wish to keep it offline even before the first use, or better to create the getnewaddress and its private key while connected to the internet? Also if it is fine to do generate the address offline, how the blockchain will locate it when i send funds to it while it never been online before?

Also how can I import the address later on any other service? How does it know that the private key I wrote is the real private key of the address? Isn't it strange if there's no big database online for the addresses and private keys?


texts: I have a physical cascius bitcoin from 2012 and would like to check that it is still valid and usable. Please could anyone tell me how i can verify its authenticity without removing the hologram.


texts: Why is data stored in reverse in the blockchain files?

texts:
I'm parsing the binary data from the bitcoin core blockchain blkxxxxx.dat files.
If I read out the magic number I get this:

\xf9\xbe\xb4\xd9\

Why isn't it stored the other way around, as the magic number is d9b4bef9? Is this just the way bytes are stored in memory?
I'm aware this is a complete noob question, but could anybody help me understand this. Thanks.


texts: E-commerce invoice in USD & receive payment in Bitcoin

texts:
Is there an e-commerce plug-in or payment processing platform that facilitates the sequence detailed below?

Merchant accepts customer's online order
Customer's credit card is charged accordingly
The dollar amount of credit card charge is:

Converted into bitcoin; *or*
Used to purchase the equivalent amount of bitcoins;

Value of customer's order (in bitcoin) posts to Merchant account
The customer receives the invoice in USD


texts: What is the legal status of a p2p fee taking App for matching bitcoin sellers/buyers?

texts:
I want to make an App in the US which would help bitcoin sellers to find buyers for cash in a local area. The app would not hold any bitcoin fund, it would only serve as a tool for buyers/sellers to meet each other, and do some transaction broadcasting/verifying.

Also, I want to monetize the application, by enforcing the users to pay a fee in order for the transaction to go through. All of this without holding any funds, thanks to P2SH transactions. I would like to know if this model of application has to comply with AML/KYC rules, or if the users can stay anonymous.


texts: Does getblockcount return the correct block count when running in prune mode?

texts:
I am currently running a bitcoin node with prune=550.

The getBlockCount from $ bitcoin-cli getblockcount does not match https://blockexplorer.com/api/status?q=getBlockCount.  As I understand it, the bitcoind is still syncing the node since the bitcoin-cli getblockcount is rising at a steady pace.

Will the getblockcount from a node running with prune=550 eventually match the official getblockcount?


texts: Would a Schnorr PubKey be a different length than a Taproot PubKey like P2WPKH and P2WSH?

texts:
A P2WPKH PubKey is shorter than a P2WSH PubKey. Would this also be the case that a Taproot PubKey is larger than a Schnorr PubKey?
If so, wouldn't people be incentivised to use the Schnorr PubKey and as a result Taproot would be less fungible?


texts: Estimated profit of a $400 21's RaspberryPi-ASIC computer?

texts:
So I'm thinking of buying one of the newly-announced $400 USD 21's RaspberryPi-ASIC computer.

How can I know the hashrate of its ASIC? How could I calculate the BTC profits I would get from it, per day?

PS: The purpose of buying it is not just for the mining profit, although I'm still interested to know on what scale of magnitude these profits are.


texts: It appears that Ethereum will start out with PoW and switch to PoS later. If I remember correctly, the block interval is planned to be fairly short in Ethereum. How does Ethereum manage to achieve consensus?


texts: hardfork is coming. Is there any risk to use an application? I will have the same bitcoin balance after  fork's procedures are completed?


texts: Why does Blockchain.com service gets stopped after a time?

texts:
I've installed Blockchain.com local machine on our server and ran its service using the command below:

blockchain-wallet-service start --port 3000

It works well, but after an unknown time, it seems that service gets stopped and I have to execute the command above again to be able to call APIs. Do you know what is the reason? Is there any limit on being that service active? And finally, do you have any special solution to make this service active all the time?


texts: Can I limit the back-up data in wallet.dat?

texts:
I want to know is it possible to back-up manually from wallet.dat. I am running Dogecoin daemon locally.

Scenario:

say user (user1) have some dogecoin balance in addr1
another user (user2) have dogecoin balance in addr2
I want to back-up only user2 not user1

Is there any way to limit the back-up data in wallet.dat file?


texts: Why not use address in raw transaction instead of public key bytes

texts:
In raw transaction, bitcoin using bytes of the public key, like:
042daa93315eebbe2cb9b5c3505df4c6fb6caca8b756786098567550d4820c09db988fe9997d049d687292f815ccd6e7fb5c1b1a91137999818d17c73d0f80aef9

It takes a lot of bytes.
Technically, can we use bitcoin addresses (e.g.1MBngSqZbMydscpzSoehjP8kznMaHAzh9y ) instead to make the blocks smaller?


texts: Does the BTC-e API have a method to transfer bitcoins?

texts:
It seems crazy to me that one of the largest exchanges could forgo including a methed in their API to transfer bitcoins from one address to another, but this seems to be what BTC-e has done.

Does anyone know of a way to transfer bitcoins using BTC-e's API?


texts: What is the "unit of account" in terms of Bitcoin?

texts: Traditional economics depend on a "unit of account".  Can anyone explain how a "unit of account" would be manifested in Bitcoin if so desired?


texts: Did Satoshi transfer several bitcoin domains before disappearing?

texts:
Wikipedia Satoshi's page says that:

  Nakamoto continued to collaborate with other developers on the bitcoin software until mid-2010. Around this time, he handed over control of the source code repository and network alert key to Gavin Andresen, transferred several related domains to various prominent members of the bitcoin community, and stopped his involvement in the project.

Is the domain transfer information correct? Does anyone know which ones?

Source: https://en.wikipedia.org/wiki/Satoshi_Nakamoto


texts: Is there a good blockchain explorer like blockchain.info available for bitcoin cash?

texts:
I usually use www.blockchain.info for bitcoin if I want to get information about:

a specific address (transactions, balance...)
a specific transaction (source and target address, amount, fees, etc.)
number of unconfirmed transactions on the network

Is there a similar site for bitcoin cash? Google was not very helpful because it gave me lots of results applicable only  to bitcoin and not bitcoin cash. Thanks!


texts:
I'm new to bitcoin. Is there a website where I can type amount of BTC I want to send and type of transaction - Urgent, Normal, Economic and they give me the price in USD how much the transaction fee will be ?
For now I just found this https://bitinfocharts.com/comparison/bitcoin-transactionfees.html
There I can see that transaction fee is 0.4$. But I don't think it could be so low.


texts: How many addresses are there now with segwit?

texts:
Could you help me understand if with segwit activated do we have more available private keys and addresses in the Bitcoin universe?

With Legacy [1...], Compatible [3...] and Bech32 [bc1...] addresses do we have 3x more possibilities ?

Thank you.


texts:
Could you please explain gettxoutsetinfo, what is it used for? What are the different fields in the output?

I assume that it's used to calculate the amount of the unspent trasaction outputs in the blockchain. What is bytes_serialized and hash_serialized?

{
  "height" : 225494,
  "bestblock" : "00000000eb0443fd7dc4a1ed5c686a8e995057805f9a161d9a5a77a95e72b7b6",
  "transactions" : 335344,
  "txouts" : 2221582,
  "bytes_serialized" : 72130407,
  "hash_serialized" : "3d14832b1b468f52ce942d4b9dc0c76a54fa6865207ff64540105403e3109f43",
  "total_amount" : 10886823.50380013
}


texts: Error on Installing Multibit for Windows 7?

texts:
I recently found about Bitcoin through a friend and got interested to surf about it over the Internet. I was installing Multibit on my machine running on Windows 7 but as soon as I click on the downloaded file, I get the following error.

This forum is not letting me attach an image so i have to manually type in the text :S

"Error:java.lang.AbstractMethodError:org.apache.xecres.dom.DocumentImpl.setXmlVersion(Ljava/lang/String;)V"

Please help me fix it !

Regards, Maddy


texts: How does the Lightning network work in simple terms?

texts:
Could you please describe how the Lightning network is supposed to work?
How does it scale better than pure blockchain transactions?
What are the advantages and disadvantages of Lightning Network and blockchain transactions?


texts: Why doesn't Bitcoin migrate to proof-of-stake?

texts:
After reading a little bit about different consensus algorithms, I am just trying to understand why Bitcoin still uses proof-of-work. This consensus algorithm being exponentially expensive, and resource intensive, doesn't it make more sense for Bitcoin --the most expensive cryptocurrency out there-- to migrate to proof-of-stake?

Currently, Bitcoin transactions are so expensive that day-to-day transactions, like buying a cup of coffee, can be more expensive than the good/service itself in some parts of the world, which fails to deliver one of the original goals of Bitcoin. That is to be the common person's every-day money.

Why does Bitcoin stick to the proof-of-work consensus algorithm?


texts:
Why does bitcoin use TCP instead of creating a web server and using HTTP to comunicate between the nodes?

What's the advantage of using TCP over a HTTP server?

Is that important?


texts:
I would like to incorporate MultiBit into a wordpress(woocommerce) based site I am designing as a checkout/payment option.

Is this at all possible and if so how do I go about it?
I cannot find any resources or tutorials on the web on how to do this.

Thank you for your time.
Peter.


texts: Understanding getchaintips in terms of chain reorganisations

texts:
I'm trying to get an understanding of the chain reorganisations my node has experienced by looking at bitcoin-cli getchaintips.

The "status" of the different branches tells me the following:

1.  "invalid"               This branch contains at least one invalid block
2.  "headers-only"          Not all blocks for this branch are available, but the headers are valid
3.  "valid-headers"         All blocks are available for this branch, but they were never fully validated
4.  "valid-fork"            This branch is not part of the active chain, but is fully validated
5.  "active"                This is the tip of the active main chain, which is certainly valid

However I'm not 100% sure what each of these mean in terms of a chain reorganisation. Would I be correct in saying the following:

valid-fork - My node performed a chain reorganisation. I downloaded and validated the blocks in the branch and had them as part of my active chain, but later deactivated them after receiving a new longer chain.
valid-headers - My node observed a possible chain reorganisation. I heard about a competing longest chain, however I did not download the full blocks and activate them as the branch never became longer than my current active chain.
headers-only - My node observed a possible chain reorganisation. I received some (but not all) of the block headers for a competing branch?

Does that sound about right?

I'm trying to get a more practical understanding of what my node is doing when it hears about a potential chain reorganisation. I'm most unsure about the difference between headers-only and valid-headers.


texts:
I have read Ledger devices can handle multiple "applications". I suppose an application means a cryptocurrency (btc, eth, etc.).

Is there a private key for each application or is it a single private key for all applications ?

Thanks


texts: Bitcoin adder or bitcoin generator or bitcoin hacker software

texts:
Nowadays I always see many persons selling bitcoin adder / bitcoin generator or bitcoin hacker software claiming that these are creating 1 bitcoin or more.

I am unable to believe authenticity of their claim.

Can any one make me clear whether these programs work or merely are scams.


texts: Bitcoin Core: receiving a transaction before being synced

texts:
I want to make a testnet transaction to my wallet, but bitcoind is currently syncing.
Once synced, will i be able to see my balance?


texts:
I am confused setting up nameserver to run with dnsseeder. I modified dnsseeder to work with my new altcoin.

Here is what is did.

I have vps.example.com setup with amazon ec2 and i compiled dnsseeder. I go to godaddy dns settings of my domain example.com and added my 1.2.3.4 (elastic public ip)

Hostname in Godaddy

vps.example.com  mapped to 1.2.3.4

and the nameservers in godaddy domain are like this

Type    Name    Value   TTL Actions
A   @   1.2.3.4              1 Hour
NS  @   ns27.domaincontrol.com  1 Hour
NS  @   ns28.domaincontrol.com  1 Hour
NS  dnsseed vps.example.com 1 Hour

Then i run dnsseeder

./dnsseed -h dnsseed.example.com -n vps.example.com -m root.example.com

Supporting whitelisted filters: 0x1,0x5,0x9,0xd
Loading dnsseed.dat...done
Starting 4 DNS threads for dnsseed.citizenshipcoin.org on vps.citizenshipcoin.org (port 53).......done
Starting seeder...done
Starting 96 crawler threads...done
                                                                                [18-03-07 00:49:14] 0/1                                                                                [18-03-07 00:49:15] 0/1 available (1 tried in 2s                                                          [18-03-07 00:49:16] 0/1 available (1 tried in 3s, 0 new, 0 active), 0 ba                                  [18-03-07 00:49:17] 0/1 available (1 tried in 4s, 0 new, 0 active), 0 banned; 0 DNS requests, 0

when i query nslook, it is not returning any dns ips.

$ dig -t NS dnsseed.example.com

; <<>> DiG 9.7.3 <<>> -t NS dnsseed.example.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 44679
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;dnsseed.example.com.   IN  NS

;; Query time: 1554 msec
;; SERVER: 192.168.0.1#53(192.168.0.1)
;; WHEN: Wed Mar  7 01:40:44 2018
;; MSG SIZE  rcvd: 45

It seems something is wrong. I am supposed to receive multiple set of IPs as answer.

What did i do wrong?

Thanks for your helpJ


texts: How does a bitcoin transaction enter the network?

texts:
I am trying to understand Bitcoin at a more fundamental level. I'd like to know how a new transaction enters and propagates across the network? I've read many Bob and Alice type scenarios where it's said that "the transaction is broadcast to the network". If there are many nodes on the Bitcoin network, how does the wallet know which node to initially broadcast the transaction to?

EDIT

Just for clarification, I'm referring to the process of sending from the client wallet (e.g. Mycelium on Android) to Node 1, before it gets propagated to all other nodes. How does my wallet know which node to send to first, or does it just randomly pick one?


texts: What are mastercoins used for in Mastercoin?

texts:
What are mastercoins used for in the Mastercoin system?

In Bitcoin, bitcoins are the only store of value and are spent as fees that the miners earn. In Ripple, ripples are used as a meta-currency accepted by everyone and are spent as fees that decrease the supply of ripples.

Does Mastercoin use any of those models? Are mastercoins the primary store of value in the Mastercoin system, or can one use bitcoins? Are they used for paying fees? If so, is anyone earning the fees and how?


texts: What's the best way to transfer bitcoins between two exchanges?

texts: I'd like to transfer bitcoins in my Kraken account to my Poloniex account. What would be the best (a.k.a. cheapest) way to do that?


texts: Decentralized Data Storage System in NXT - How do you disable the 2 week data pruning?

texts: Currently the NXT platform has the ability to store data in its blockchain, whereby making it a decentralized data storage system. But the thing is that the data is purged from a nodes blockchain every 2 weeks to reduce bloat and only keeps a hash of the file only. I read that you can host nodes that disable this pruning of the data and keep the data indefinitely. How can this be done?


texts: Do we know which mining software Satoshi used?

texts: I am trying to figure out why the mining software is not included in the coin wallet you wish to mine and why do we need to find some third party less trustworthy sources to mine


texts: How to run and access Blockchain.info platform on a remote server?

texts:
I've installed Blockchain.info local machine on a server and got an API key for it. But it seems it's designed to work only locally and on the port 3000.
I need to call APIs from another server with a certain IP. Unfortunately, I could not find anything about how to access to BlockChain.info machine and its APIs by calling a server IP instead of localhost or 127.0.0.1, and how to change the default port 3000 to something else.
May you help me please?


texts: What was the first official BTC miner software?

texts:
I know that the first and official wallet is bitcoin-qt. This wallet has code here: https://github.com/bitcoin/bitcoin

What was the first official miner software? I understand that bitcoin-qt never use as miner software. Where is official code of miner software?


texts:
I am having trouble with a (400) bad request on POST requests.  I am able to execute all Get and Delete requests with the same signature process, but obviously the body is string.empty. We have tested all sorts of different JSON formatting to try and get this to work, but it is not working. We have not been able to find an example of ANY prehash signature to compare to.  Also, unless the POST server time is different than the GET and DELETE server times we have the correct timestamp as we are within 1 second of the GET/time API call for server time.  GDAX allows for 30 second buffer to authenticate.

Public Shared Function placeOrder()
    Try
        Dim Body As String = "{""type"":""limit"",""side"":""sell"",""product_id"":""BTC-USD"",""price"":""20000"",""size\"":""0.02235229""}"
        Dim ts As String = GetNonce()
        Dim method As String = "/orders"
        Dim str_GDAX_Main As String = "https://api.gdax.com"
        Dim sig As String = GetSignature(ts, "POST", method, Body)
        Dim fr As System.Net.HttpWebRequest
        Dim targetURI As New Uri(str_GDAX_Main & method)
        'Dim response As String

        Dim jsonDataBytes As Byte() = Encoding.UTF8.GetBytes(Body)

        fr = DirectCast(HttpWebRequest.Create(targetURI), System.Net.HttpWebRequest)
        fr.Headers.Add("CB-ACCESS-KEY", config_API_Key)
        fr.Headers.Add("CB-ACCESS-SIGN", sig)
        fr.Headers.Add("CB-ACCESS-TIMESTAMP", ts)
        fr.Headers.Add("CB-ACCESS-PASSPHRASE", config_API_Passphrase)
        fr.UserAgent = UserAgent
        fr.Accept = "application/json"
        fr.Method = "POST"
        fr.ContentLength = jsonDataBytes.Length

        Dim stream = fr.GetRequestStream()
        stream.Write(jsonDataBytes, 0, jsonDataBytes.Length)
        stream.Close()

        Dim response = fr.GetResponse().GetResponseStream()

        Dim reader As New StreamReader(response)
        Dim res = reader.ReadToEnd()
        reader.Close()
        response.Close()
        Return res

        'If (fr.GetResponse().ContentLength > 0) Then
        '    Dim str As New System.IO.StreamReader(fr.GetResponse().GetResponseStream())
        '    response = (str.ReadToEnd())
        '    str.Close()
        'End If

        'Form1.RichTextBox1.Text = (response)
    Catch ex As System.Net.WebException
        MessageBox.Show(ex.Message)
        'Error in accessing the resource, handle it
    End Try
End Function

Public Shared Function GetNonce() As String
    Return (DateTime.UtcNow - New DateTime(1970, 1, 1, 0, 0, 0)).TotalSeconds.ToString()
End Function

Public Shared Function GetSignature(nonce As String, method As String, url As String, body As String) As String
    Dim message As String = String.Concat(nonce, method.ToUpper(), url, body)
    Dim encoding = New ASCIIEncoding()
    Dim keyByte As Byte() = Convert.FromBase64String(config_API_Secret)
    Dim messageBytes As Byte() = encoding.GetBytes(message)
    Using hmacsha256 = New HMACSHA256(keyByte)
        Dim hashmessage As Byte() = hmacsha256.ComputeHash(messageBytes)
        Return Convert.ToBase64String(hashmessage)
    End Using
End Function

We have no idea if our body is incorrect or if the URI is incorrect or what the problem is.  If someone can take a look at it and figure out where our body syntax error is.  Or if we should look elsewhere.


texts:
I'd like to understand taint analysis quantitatively. Blockchain.info offers a service that will calculate taint, but I've found no good explanation for how taint is calculated.

The best (and only) explanation I've found so far appears in the paper Anonymity of Bitcoin Transactions:

  The taint analysis works by calculating the percentage of the
  amount of bitcoins that might origin from another address,
  thus revealing connections in the transaction graph. In the
  simplified example in Figure 4, A1 and A3 would have a taint of 75% and A2 a taint of 25%. However, it can only detect direct connections in the graph and does not consider any
  context information.

This explanation is confusing. Taint is measured between two pseudonyms (addresses). It's not a property of a particular pseudonym. The paper seems to be missing the part that says the taint scores for A1, A2, and A3 are relative to A4. If so, then the scores make sense.

However, it's not clear what would happen for more complex chains of ownership. For example, imagine another pseudonym, A5 that pays A1 5 BTC. What would be the taint score between A5 and A4?

I've seen this, but it doesn't discuss how to compute a taint score between two pseudonyms.

What I'd like to see is the outline of a step-by-step procedure for calculating taint, as done by Blockchain.info. If I had to guess, here's how the procedure would look:

Find two pseudonyms, S (source) and T (target). Funds flow from S to T.
Using the block chain, find a chain of ownership Ci from each coin controlled by S to T.
For each chain of ownership Ci, find the lowest valued coin transfer mi.
Sum all mi, giving m.
Sum the value of all outputs received through T, giving s.
Taint is defined as m/s.

Using this procedure would give a taint score of 50% between A5 and A4 (2 / 4).

Is this correct?


texts: Bitcoin Public Key To Address Uncompressed

texts:
So after searching for HOURS on here and overall on the internet, I haven't managed to find an answer to my question so I'll ask here.

So I've been trying to convert a public key into an address. I've been writing all the hashing algorithms, and tested them with online hashing websites, so they are working. Here is my code:

function getBTCAddress(public_key)
{
   var __SHA = SHA256_hash(public_key);
   console.log("__SHA: " + __SHA);
   var RIPEMD = RIPEMD_160(__SHA);
   console.log("RIPEMD_160: " + RIPEMD);

   var new_SHA = SHA256_hash(RIPEMD.toString());
   console.log("new_SHA: " + new_SHA);
   var _new_SHA = SHA256_hash(new_SHA);
   console.log("_new_SHA: " + _new_SHA);

   var checksum = _new_SHA.slice(-8, _new_SHA.length);
   console.log("checksum:" + checksum);

   var almost_address = "00" + RIPEMD.toString() + checksum;
   console.log("almost_address:" + almost_address);

   var buffer = Buffer.from(almost_address, "hex");

   return BS58.encode(buffer);

}

For some reason it is not giving me the proper results. I'm wondering, what are the exact steps of deriving an address from a public key?

For those of your who are wondering here is what my code is doing:

  checksum = SHA256(SHA256(RIPEMD160(SHA256(public_key)))) <-- get last 8 bytes

  almost_address = 0x00 (network byte) and RIPEMD160(SHA256(public_key)) and checksum <-- compacted into 1 string

  address = base58(almost(address)


texts: Obtaining Bitcoin Cash generated at the fork in August 2017

texts: I had Bitcoin in my ANX Wallet at the fork in August 2017 I transferred it to my Blockchain wallet in September. Is there any way I can obtain the Bitcoin cash generated at the fork?


texts: Standard Transactions and relaxation rules

texts:
We all know that there 5 common types of Standard transaction scripts. My question is if we create a script under what rules is it decided if it standard or non-standard?

Under the hypothesis that it is non-standard if some miners accept then what happens? It will be included in a block only if these miners succeed in creating a block?

Furthermore signing transactions without SIGHASH_ALL but with any other hash type is considered non-standard?


texts: Is Bitcoin trading anonymous and untraceable?

texts:
I know little about bitcoin except they are digital currency.

I heard that bitcoin ownership or exchanges/trading is anonymous and untraceable by government. Is that true?
If I buy a bitcoin and pay by credit card, the money goes through banking system right? That would make it traceable wouldn't it?

Thanks in advance.

Appended: Thank you for the all answers that are informative. The reason I asked is because I heard that the underworld and money launderers etc. use bitcoin to evade governments' scrutiny which is part of the reason for its price soar. Guess there is no truth in that since transactions are traceable.


texts: What happens if I send small amount of btc lesser than fee?

texts: I tried to deposit a small amount of btc in localbitcoins.com, but it was smaller than their deposit fee so it was not processed by them, now what will happen to that chunk? and can I get back the btc?


texts: How do non-standard transactions get created, broadcast and mined?

texts:
Can someone explain how this transaction was validated, broadcasted and mined?

When i looked at the scriptsig it only had the hex value for OP_True.

https://blockchain.info/tx/91c8b08f305d895d6bc8f43bbdd36dcbc7f1d998e3df5e8f13dd9cdeebf15cb5?show_adv=true
Also how can i create a transaction like this and have it broadcasted and mined?


texts: Is bitcoin the most powerful computer network in the world?

texts: I read an article from twenty THIRTEEN saying, as of then, bitcoin had more power than the top 500 supercomputers. At that time, the difficulty was 21.3 million. Now, it is almost 11 trillion and projected to pass that number within September 2019. So, using that info, the computer says that the network uses 350,000 times as much (SHA256 brute forcing) computational power as those computers did. Is that still true and if so, what is the number of times more powerful now?


texts: Can any Bitcoin client do local peer discovery and blockchain synchronization?

texts:
Usually, when a full Bitcoin client such as bitcoind, Bitcoin-QT, or Multibit start on a fresh installation, they connect "to the network" to download the blockchain. If someone has multiple computers or devices, they could end up downloading the whole blockchain several times. This puts a lot of stress on their connection and extra clients on the network that could get their data locally.

Have any clients implemented a standardized way to exchange blockchain data locally, without going over the Internet?

I imagine this would work something like how BitTorrent local peer discovery works, where two clients on the same subnet discover each other through multicast groups and then negotiate transfer of data.


texts: Does finding neighbors in Bitcoin consider locality and hop count?

texts: When the list of neighbors is being gathered by a new nodes in the network, does it consider the distance between the nodes to find closest possible, or it just takes some random nodes? In other words, are neighbors in bitcoin network, close to each other or they are usually departed from each other by many hops?