texts: Bitcoin testnet3: unable to push/publish raw transaction: how to verify validity of transaction?

texts:
I have created a raw transaction and am now trying to push the hex format into testnet3. I have used following two ways and both are giving me two different errors, first one:

curl -d '{"hex":"TX_HASH"}' http://tbtc.blockr.io/api/v1/tx/push

I get this error:

{"status":"fail","data":"Could not push your transaction!","code":500,"message":"Did you sign your transaction?"}

and second one using this link:

https://test.webbtc.com/relay_tx

gives me this error:

Testnet3 - Error - Request took too long.

Not sure if signature is really the problem here. I used decode api from blockr.io to check my message - it seems well formed and is 226 bytes in length. I played around with fee wondering if that was an issue, but I think i have ruled that out as well.

I have also checked the validity of signature in the code (inspired by David De Rosa's guide).
Any tips on how can I verify the validity of my transaction?

Thanks.

Edit: Now I am getting this very descriptive error message from blockr:

{"status":"error","data":"NULL","message":"It's looking like you may have taken a wrong turn. Don't worry... it happens to the best of us.","code":404}

Wish these guys didn't employ their sense of humour in error messages :(

used blockcypher api to push the raw transaction. This is the error message I get:

Error sending transaction: Error running script for input 0 referencing 87ce205d61e4bf63c0bcc42db1a58c36a2cac0048df32e470f3dc1bd39741367 at 0: Script was NOT verified successfully..

After signing the transaction, I checked for signature verification using ECDSA_verify(0,digest, sizeof(digest), sig, sig_len, key) and this function call returns 1 - So I assumed my signature is correct. Am I wrong in assuming this? Am I missing something big here?


texts: While mining on a NOMP mining pool, I noticed that when you add the confirmed blocks and pending blocks together, they rarely add up to the total blocks found. It is my understanding that the missing blocks were "kicked." What does it mean when a block is "kicked"?


texts:
In March 2013 there was a fork following the v0.8 release. The issue was resolved rather efficiently, as explained in the post-mortem report. However in this process there were winners and losers: the miners building on the v0.8 chain had to give up their block creation fee.

The next time there's a fork like this, it may not be so straightforward. The miners may not all agree on the proper resolution for the issue.

Is there any documented set of rules (bye-laws) explaining how such forks are to be resolved in the future?

If there's a conflict among the parties involved, who has the final say?

PS: Any comments on Bitcoin's so-called (faux) "decentralized" architecture are also welcome, given my other question has been censored. The decentralization doesn't seem to work after all, which begs the question as to what the whole point of the proof-of-work scheme is anyway.


texts: Would it make any sense to order ASIC miners now?

texts:
I'd like to order some Jalapeños (the 5 Gh/s models) from Butterfly Labs; I'm thinking about 4 of them.

I know I'd be looking to a delivery time of 3-6 months; and I know perfectly well that mining difficulty will increase dramatically in the next few months.

With current BitCoin exchange rates, it would take ~10 BTC to repay the cost of the Jalapeños; but will they be able to mine 10 BTC in a reasonable time, 3-6 months from now?

Would it make any sense at all to place the order now?


texts: What is a good mining pool/payout model for infrequent mining?

texts: I usually mine only, when I do stuff using my PC so it is on anyway. So far I used Slushs Pool but they have a score based reward system, which seem to punish casual mining. If a long round ends >15 minutes after leaving the pool (due to shutdown the system) you'll probably get nothing at all. What are better payout models for the casual miner and what pools can be used?


texts:
Who runs the Bitcoin Wiki? What is their Twitter account?

I am looking for the community, group or person who runs this site.
Does this being have a Twitter account? The account @bitcoin_wiki exists, but they have only 30 followers, which makes me think they aren’t the real people: so small a follower count doesn’t feel right.

I ask because the site is down and Twitter is a very easy way tell the site administrators. I suppose another method of contact would be fine too.


texts:
I work with a bitcoin wallet app using the Java/BitcoinJ. The app has custom features such as showing balance, transactions, address and sending option. It was running fine and suddenly, I get the blockChainDownloadLocked ignoring the duplicate request error in the app.

org.bitcoinj.core.Peer: 06/19/2017 16:26:28 - blockChainDownloadLocked(00000000b873e79784647a6c82962c70d228557d24a747ea4d1b8bbe878e1206): ignoring duplicated request: 00000000076d710f40120e2f6693371bf6a7c4a9d149fb665664272a91dccf5a
org.bitcoinj.core.Peer: 06/19/2017 16:26:28 - java.lang.Throwable
    at org.bitcoinj.core.Peer.blockChainDownloadLocked(Peer.java:1446)
    at org.bitcoinj.core.Peer.processInv(Peer.java:1247)
    at org.bitcoinj.core.Peer.processMessage(Peer.java:489)
    at org.bitcoinj.core.PeerSocketHandler.receiveBytes(PeerSocketHandler.java:182)
    at org.bitcoinj.net.BlockingClient.runReadLoop(BlockingClient.java:122)
    at org.bitcoinj.net.BlockingClient$1.run(BlockingClient.java:81)

I use IntellIJ and cleared the Cache (Invalidate Cache/ Restart ...) and deleted the target folder to resolve it. It didn't help. Later, on enter in the Cache folder in the Mac OS and deleted everything inside all the folders.

I think rolling back the entire blockchain would be a solution, but, open for better suggestions.

What's the issue here and how to solve?


texts: Calculate fees with Blocktrail/btc.com SDK

texts:
First of all hi and thanks for your support and your time.

I want to calculate the fees of a blocktrail transaction with blocktrail SDK, before making the transaction, in order to let the recipient pay fees.

Here is what I tried:

$FEES = $wallet->coinSelection(\Blocktrail\SDK\Wallet::normalizeOutputsStruct(['66f4dec6ab29cd056ce1814c6fdfee05e1524b36' =>'100000']),false,false,\Blocktrail\SDK\Wallet::FEE_STRATEGY_LOW_PRIORITY;
echo "$FEES";
$fee = $FEES['fee'];
echo "$fee";

But this don't work, it says this: Fatal error: Uncaught Blocktrail\SDK\Exceptions\BlocktrailSDKException: Address not recognized how can I fix this error? Thanks for read, hope that you'll have a nice day :)


texts: GUIMiner gives "ValueError: need more than 1 value to unpack"

texts:
I'm trying to get started mining with kiv's GUIMiner. I started, and get this error message:

  ValueError: need more than 1 value to unpack

How should I solve this?


texts: Does btc-e require verification for coin to USD conversion

texts:
I know that btc-e requires verification to withdrawal USD,
but do they require verification to convert to USD and let sit until I want to trade it for other coins?

Again.. NO usd withrawal. only BTC->USD -- USD->BTC/LTC/etc


texts: Calculating fee based on fee rate for bitcoin transaction

texts:
I'm writing an algorithm for calculating fee based on fee rate and amount to be sent (requested amount) in order to propose the fee to user;

Sorting UTXOs ascending based on value
Take enough UTXOs so sum is larger than requested amount
Calculate change, add to outputs
Build tx
Calculate fee based on tx byte size times fee rate
Is Change larger than calculated fee? (can we "fit" fee into change)
If no: go back to step 2 and add more UTXOs to get to fee
If yes: reduce the Change for fee and build final transaction

This works well in most cases, but if you have large number of UTXOs with small values and fee rate is large (e.g. 88 sat/byte), you can end up with very large transaction, i.e. very large fee for sending very small amount of coins.
I have tried to make a change in algorithm where after X number of iterations, I would give up and try to take enough UTXOs for requested amount and deduct fee from that amount and send what ever is left.
But I ended up in long loop again, as UTXOs were small, transaction large and in every iteration I didn't had enough to pay the fee.
As this is obviously bad implementation, is there any other way to calculate fee bases on fee rate?


texts: is there a way to run bitcoin-qt and point it to a local testnet?

texts:
I'm running a small testnet locally with this project:

http://github.com/freewil/bitcoin-testnet-box

but I'm having trouble pointing bitcoin-qt to the blockchain that I created locally myself, so I have some data like this:

bitcoin-cli -datadir=1  getinfo
{
    "version" : 90300,
    "protocolversion" : 70002,
    "walletversion" : 60000,
    "balance" : 0.00000000,
    "blocks" : 0,
    "timeoffset" : 0,
    "connections" : 1,
    "proxy" : "",
    "difficulty" : 0.00000000,
    "testnet" : false,
    "keypoololdest" : 1413617762,
    "keypoolsize" : 101,
    "paytxfee" : 0.00000000,
    "relayfee" : 0.00001000,
    "errors" : ""
}
bitcoin-cli -datadir=2  getinfo
{
    "version" : 90300,
    "protocolversion" : 70002,
    "walletversion" : 60000,
    "balance" : 0.00000000,
    "blocks" : 0,
    "timeoffset" : 0,
    "connections" : 1,
    "proxy" : "",
    "difficulty" : 0.00000000,
    "testnet" : false,
    "keypoololdest" : 1413617762,
    "keypoolsize" : 101,
    "paytxfee" : 0.00000000,
    "relayfee" : 0.00001000,
    "errors" : ""
}

and I want that to be the data, and the addresses that is picked up and incorporated by bitcoin-qt. I guess there should be some flags to facilitate this but everything I've tried so far always in unsuccessful- maybe someone on here knows or has some idea?


texts: What happens if there are no transactions?

texts:
Could you please explain what would happen without transactions?
Let's say people stop s(p)ending for a while for whatever reason.
What miners would do if there are no transactions? Will they just keep a copy of blockchain and have no reward for approving transactions?


texts: Are Bitcoins contained associated with a wallet or with an address in a wallet?

texts:
What I want to know is, if I have a wallet with several addresses containing 10 BTC (let's say 1 BTC per address) in total and I want to send 5 BTC to a person, but first generating a new address (as this is advised for privacy reasons). What happens then?

Are the Bitcoins from 5 random addresses first accumulated into the address I just generated, after which I can then use it to send the money to the receiving party?

Or how does it work?


texts: How do I convert a private key in hex to a Segwit private key expected by Electrum?

texts:
I've been following this code to generate SegWit addresses with python. However, I'm confused because this script doesn't output the private key in a usable way for Electrum.
I found this site which told me how to convert the key to a compressed WIF.
Here's one example, I ran the script and got this output:
Private key: ce534f3d1f481f8736c30d866a6b2c5defe5edc36afaafc0e923586791a2462b
Verifiction key: e5ee63efe153ebf1ec537831f2fba227f4b5f80275e750a9d0a8284c9fb4f91fb5427e034ffec25bacc346263f0f6281f951926f924f7c53f771f632ca9e3cbb
Compressed public key: 03e5ee63efe153ebf1ec537831f2fba227f4b5f80275e750a9d0a8284c9fb4f91f
keyhash: 17f022e2c24238760a0a1b070eaa456df4e8b915
Native address: bc1qzlcz9ckzggu8vzs2rvrsa2j9dh6w3wg4atezy6
P2WPKH_V0: 001417f022e2c24238760a0a1b070eaa456df4e8b915
Hashed P2WPKH_VO: b9502db522524782980563a09355fa7052ee7ff1
P2SH_P2WPKH_V0: a9b9502db522524782980563a09355fa7052ee7ff187
Checksum: 7fcb7c1d
Binary address: 05b9502db522524782980563a09355fa7052ee7ff17fcb7c1d
Nested address: 3JarywCp1dbFiykdGNWyo5pdZyvSLEGZ96

I then added my own additional code to convert to WIF.
WIF: 5KP9tSHuzYd1WTCTwr5ewace9eNM8Kv8xjsWYyELHdEkKcQkiUZ
Compressed WIF: L48nE2detzZwEzdbw5dYTuNJy9wDqLVY92DwS7Br8NwgD6S8NiyT

I imported the compressed WIF key into Electrum, but I get 13BaDNdBXkfrGkvJT41HNosBBbbLZRWyZJ as a public key. Everything online confirms that only legacy addresses begin with a '1', but surely it is a SegWit address, no?.
When I view 'details', Electrum gives me the correct compressed public key (03e5ee63efe153ebf1ec537831f2fba227f4b5f80275e750a9d0a8284c9fb4f91f).
Why doesn't Electrum give me a bech32 address or a nested address? Have I done the correct conversion of the private key?
Here's my code just in case there's an obvious mistake somehow.
fullkey = '80' + (private_key.hex())
sha256a = hashlib.sha256(binascii.unhexlify(fullkey)).hexdigest()
sha256b = hashlib.sha256(binascii.unhexlify(sha256a)).hexdigest()
WIF = base58.b58encode(binascii.unhexlify(fullkey+sha256b[:8]))

compressedPubKey = private_key.hex()+'01'
compressed_fullkey = '80' + (compressedPubKey)
compressed_sha256a = hashlib.sha256(binascii.unhexlify(compressed_fullkey)).hexdigest()
compressed_sha256b = hashlib.sha256(binascii.unhexlify(compressed_sha256a)).hexdigest()
compressed_WIF = base58.b58encode(binascii.unhexlify(compressed_fullkey+compressed_sha256b[:8]))


texts: Estimatefee value not corresponding to actual fee

texts:
When I call estimatefee 1 in testnet it returns: 0.00044444

Then when I call sendtoaddress xxxxxx 0,1 (which got the first confirmation within a couple of minutes after sending) I see that the fee included is: 0.00001662 BTC, which is about 27 times smaller that the original estimate.

What am I missing?


texts: How to upgrade my node with bitcoin wallet GUI from 0.11.2 to 0.12.1? Install qt V5.5?

texts:
i want update my RaspNode (rPi 2 B+) to the 0.12.1 but i want to use Bitcoin wallet GUI. So, it's necessary to install QT V 5.5...
V 0.11.2 use QT 4.8, but 0.12.1 uses QT V 5.5

How to install QT V 5.5 for raspberry ??


texts: What is a mechanism of method how to get the data in the blockchain(e.g. bitcoin, ethereum)?

texts:
There are websites which have APIs that allow you to trace transactions and lookup information like specific address balances, etc. I am wondering how these web service providers are able to provide the data from the blockchain.

I think that they are running a full node 24/7 so that the end user does not need to run tun their own node and can instead query for data via the service's node.


texts: How is the USD price on Binance calculated since there is no USD involved in the whole exchange?

texts:
I'm talking about this: https://i.imgur.com/wKP17oe.png
How is it calculated?


texts: How does the 51 percent or 2/3 majority voting rule work?

texts: For a block to be added to the chain, it needs vote from majority of miners, is that correct? If yes, does that mean a single block gets worked upon by all of the miners?


texts: any way to recover lost qt bitcoin wallet?

texts: Hi is there any way to recover my Bitcoin-Qt wallet with only an address and the wallet password? Unfortunately my disk was formatted.


texts:
so i wanted to test these for somewhat educational purposes and maybe make some profit along (highly unlikely), I have downloaded bitcoin core, and synced it completly, started a local p2pool pool, and connected a bunch of PC and macs to it through GUIminer, the strange thing is, CPU even with much lower Hash rate, find more shares, also Intel graphics had more shares and accepted shares, with only about 3.9 MH/s, and p2pool local hashrate is always 0 H/s even after running the miners for 5-6 hours, why is that? is there someting wrong with GUIminer, I have tested CGminer as well, waited for 10 minutes but still no change on p2pool local hashrate, all connect through 127.0.0.1:9332, all related ports are opened.
p2pool version is 14.0 and I have followed the instructions  here http://p2pool.in


texts: Can anyone use your private key if its encrypted on bitcoin core?

texts:
I bought cold storage coins with private keys engraved. After I import and encrypt the wallet in bitcoin core, can just the private keys be used to access the wallet or would you also need the passphrash i encrypted it with?
In other words, can the manufacture access my wallet with the private keys if i encrypt the wallet on bitcoin core?


texts:
I make a JSON call to

https://blockchain.info/tobtc?currency=USD&value=1

This is a free api with a request limit.

I have just received my api_code via email. This is blockchain.info's example of how to use it

  Once approved the API Code can be passed to all requests in the "api_code" parameter e.g. https://blockchain.info?api_code=$your_code

I am guessing that they mean with PHP (because of the dollar sign) as when I type into my address bar

https://blockchain.info/tobtc?api_code=000my0-api00-code-0000-000000000&currency=USD&value=1

The data does not any look different when I use the api code with the dollar

https://blockchain.info/tobtc?api_code=$000my0-api00-code-0000-000000000&currency=USD&value=1

Though I am unsure of how to tell what is the correct way as I can access this free api with and without an api code (with a request limit). How do I tell if I am adding it correctly?


texts: Preparing a "send" order offline the same way you can create an offline wallet?

texts:
If I have several bitcoins in an offline wallet / cold storage and want to send a few bitcoins to some address, can I somehow prepare and sign the send order offline and only copy the result (say using an USB stick) to an online computer?

For example if I have a wallet with one address which has 1000 coins and want to sent 10 coins to an exchange to sell them, do I need to put my wallet.dat to a Bitcoin client which is online? (hence risking to lose it all in case the online computer I'm using is compromised)

Does it changes anything if there's change or not?

It's a theoretical question in order to better understand how bitcoin works.


texts: What does Bitcoin-Qt "Change Passphrase..." do to existing private keys and corresponding addresses?

texts:
"Change Passphrase..." obviously lets me encrypt the wallet with a new string of text.  I think (correct me if I'm wrong) that this creates new private key(s) inside wallet.dat.

How are existing addresses affected when the passphrase is changed?

Are they still linked to the old private key (previous passphrase)?
If so, should I send those Bitcoin to myself (sending them to a new address that was generated after the change of passphrase)?


texts: When did merged Namecoin-Bitcoin mining start?

texts:
(This question was originally asked before merged mining began)

When exactly did merged mining of Bitcoin and Namecoin chains start?


texts: looking at the current prices of bitcoins in different currencies it seems as one could buy some in GBP and convert sell them to get USD, than convert those USD back into GBP and make some money. is it that easy? what am i missing? thanks!


texts: Why was 21 million picked as the number of bitcoins to be created?

texts: Why did Satoshi pick 21 million as the number of bitcoins to be created? What is the significance of that number?


texts: How i can connect to bitcoin core light server?

texts:
Need a bunch of Laravel + Bitcoin Core. Need a light version of bitcoin bark. Installed as follows:

sudo apt-get install build-essential && sudo apt-get install libtool autotools-dev autoconf & & sudo apt-get install libssl-dev && sudo apt-get install libboost-all-dev && bitcoin && sudo apt-get update && bitdoin & mkdir ~ / .bitcoin / && cd ~ / .bitcoin / && nano bitcoin.conf

Config

proxy = 127.0.0.1: 9050
rpcbind = 127.0.0.1
rpcuser = user
rpcpassword = password
rpcthreads = 30
testnet = 0
rpcport = 143
server = 1
datadir = / root / .bitcoin / base /
shrinkdebuglog = 1 prune = 551 lang = ru_RU
printtoconsole = 1 server = 1

And how can I connect to this server now?
Run - bitcoind --daemon


texts:
I am working on a cryptocurrency site in which each user will have there own individual deposit address to put currency on site. I am using bitcoin-core, bitcoinjs-lib, along with quite a few other modules.

Currently I am receiving an error after running the following code via node generate_wallet.js

var bip32 = require('bip32')
var bitcoinjs = require('bitcoinjs-lib');

var privKey = process.env.BIP32_PRIV;
var hdNode = bitcoinjs.HDNode.fromBase58(privKey);

var count = process.env.GENERATE_ADDRESSES ? parseInt(process.env.GENERATE_ADDRESSES) : 1000; // how many addresses to watch

var rescan = 'false';

for (var i = 1; i <= count; ++i) {
  console.log('bitcoin-cli importprivkey ' +  hdNode.derive(i).keyPair.toWIF() + " '' " + rescan)
}

The error:

console.log('bitcoin-cli importprivkey ' +  hdNode.derive(i).keyPair.toWIF(L4tvCJoE9nxFnmZ4znCDvpqMLo9m8ybpAzxdE4ZKWDAfBqeM8JsR) + " '' " + rescan)
                                                                      ^

TypeError: Cannot read property 'toWIF' of undefined
    at Object.<anonymous> (/root/bustabit-depositor/src/generate_wallet.js:13:71)
    at Module._compile (internal/modules/cjs/loader.js:736:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:747:10)
    at Module.load (internal/modules/cjs/loader.js:628:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:568:12)
    at Function.Module._load (internal/modules/cjs/loader.js:560:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:801:12)
    at executeUserCode (internal/bootstrap/node.js:526:15)
    at startMainThreadExecution (internal/bootstrap/node.js:439:3)
root@ubuntu:~/bustabit-depositor/src#

Any suggestions would be greatly appreciated. I don't even know how to work around this as there's no results online about this. Maybe i'm just dumb haha


texts: transferring bitcoin among friends and taxes

texts: I gave my friend btc (ie sent it to their address) to trade together with their btc last week. I'm suddenly worried about taxes (in the US). If right now, they give me back exactly as much btc as I gave them, are there tax ramifications? Can I sell the btc after > a year and pay the 15% capital gains tax or whatever, or is there some short-term hold complication, and do I have to pay more?


texts: I can't find any tool to test RPC interface. I am looking for something like Postman (Chrome extenstion). I would like to send request (with login and password) and see their responses in JSON.


texts:
Please help me.  I have an unconfirmed Bitcoin transaction since three days. Below is the hash ID

a7f5f1989e0bbefeb012b22fbc8f011e5b6b0e66e802ea24242dc1d7878869bb


texts: Multisig Setup - Pruned Bitcoin Core on Computer vs. Dedicated Hardware

texts:
Are there security implications of running a pruned Bitcoin Core node on a personal computer vs. a full Bitcoin Core node on a dedicated hardware device (i.e. Raspberry Pie with Umbrel, myNode, nodl, and etc.)?

The intended use case for the Bitcoin Core node is integration with a multisig wallet such as Specter, Electrum, and etc.

This scenario presumes the personal computer is configured to run Bitcoin Core through Tor/VPN (That do not save/collect logs) as in the Specter desktop 1-click setup.

One non-security implication is the performance impact on the personal computer when running the pruned Bitcoin Core node.


texts: Bitcoin Mining as a Newbie (link wallet to another person's miner)

texts:
I'm new in bitcoin mining. I would wish to mining to make some profit. I have just talked to someone and he has told me I can partner with him to use his miner. I have some bitcoins ready with me and before I get started  I want to know how I will configure wallet to his miner.
What should I share with him and lastly how will I know that it is configured?
I'm trying to avoid being conned


texts: What can a US citizen do regarding the theft of Mt Gox PII data (Passports, etc)

texts:
A hacker is selling Personally Identifiable information (PII) stolen from Mt Gox.

What can a US citizen do to protect their identity?  What steps should they take?

Should a passport be cancelled?
Should I do anything with my credit report, or state license?


texts:
Does anyone know why I can't dump info into a text file?

It also doesn't allow me to back up my wallet.

i am using SNAP


texts:
I have my lnd node pubkey, public IP address and an open port as follows:
0286712a3a81b0d5e54469042146137fbdf7b77802f21fad1261c031a8d917f5da@...
Do I have to set parameters after the '@' sign - in some configuration file or is it enough to just use them when I provide the full address?


texts: What is the smallest ubuntu virtualbox image to run cryptocurrency software on?

texts: I'm looking to do all my crypto related stuff like storing coins and managing my coin wallets inside a virtualbox. I plan to use ubuntu as it seems most friendly with many crypto coins. What is the best and smallest image for something like this?


texts: How many addresses can be handled reliable in one wallet?

texts:
I am working on a project which may end up generating a few hundred (or even more) bitcoin addresses a day. From my understanding in theory there is no limit on the number of bitcoin addresses in a wallet, but i fear to run into scalability issues with bitcoind on the long run.

Will RAM or CPU usage increase significantly? Is there any known limit of the number of addresses?

Note: Probably 60-80% of these addresses will never receive any transaction. Don't know if this makes a difference.


texts: Historical Prices Immediately Following Bitcoin Halving

texts: I searched here for posts on historical price movements following Bitcoin halving but didn't find much.  I found some old posts that inquired about the anticipated price changes expected for future halvings, but my question is not speculative in nature, but about what has actually happened to the price of bitcoin during past halving events.  Can anyone provide a brief summary of what has happened within a few days or weeks to BTC price (or even of other relevant cryptos) in the past when a having has occured?


texts:
Is there a way to accept fiat currencies online without having a credit card and having the fiat automatically converted to Bitcoin?

I know services such as BitPay and so on let's you accept Bitcoin payments on your site but what if you want to do the opposite thing and accept Fiat currencies and have them automatically converted to Bitcoin and sent to your account? Preferably without too much sign up hassle from the merchant's side.


texts: running a full node on a network restricted to outbound connections on port 80 via proxy

texts:
Wanted to know if there is any way i can run a full node on a machine in a restricted LAN that can not exit outbound packets except to a specific proxy on port 80 ?
(an answer requiring to use an additional special server to forward packets that sits on an open network can be considered too) can SOCKS help ?


texts: Why scriptPubKey is a series of commands?

texts:
I am not fully understanding the design purpose of the scriptPubKey in the transaction output.

I think the tx's (say tx1 here) output could just be the receiver's public key's hash.

Then when the receiver want to send the money to another one, he only needs to create the transaction tx2 (with receiver's public key and the sig of the previous transaction).

Then the bitcoin net work could check:

Is the public hash(tx2.public_key) = t1.output.hash_public_key?
Verify(tx2.sign, tx2.public_key, tx1)

a+b can approve that this transaction is created by the receiver.

Therefore, I am not quite understanding why we need to save
OP_DUP OP_HASH160 next_receiver_public_key_hash OP_EQUALVERIFY OP_CHECKSIG
in the tx.output.


texts:
Checking the implementation of Buterin's bitcoin tools I've noticed something strange. According to the Bitcoin developers guide, sighash_single signs only the outputs that match the input where the scriptSig is going to be placed, that is, input i should sign only output i. However, the code is always signing the current input with the last output of the transaction.

Is it a workaround to deal with a non-matching number of inputs and outputs, or I am missing something?


texts: Electrum 2.7.9 setup never went through the password and seed setup, now I can't send coins

texts: I installed the Electrum 2.7.9 wallet and it never went through the password and seed setup. I ended up with a default standard wallet. I then uninstalled the Electrum wallet and then reinstalled it. Once again it didn't go through any password or seed setup and I had a default standard wallet on my pc. I made the dumb decision, because I am totally new at this, to go ahead and send my bitcoins from my coinbin wallet to the address associated with the standard default wallet and now I can't send anything because it wants a password. Please help!


texts: Blockchain shows a confirmed order still "unspent". How do I reclaim Bitcoin thru Coinbase, so I can place order again

texts: I placed an order thru Coinbase using Bitcoin to the address the vendor provided at checkout, and the transaction was confirmed.  However, now several days later, the Blockchain shows the Bitcoin "unspent". I never got the confirmation email from the vendor.  If the vendor doesn't spend it, due to a loss of the order or wrong wallet address, will Coinbase refund my Bitcoin, so I can try to place my order again?


texts: How do I find out what getwork would have returned for an already mined block?

texts: Lets say I want to find out what getwork would have returned for an already mined block http://blockexplorer.com/block/00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d. How would I go about doing this?


texts:
I sent some money 3 hours ago my BTC client (Bitcoin Core) still says the payment is unconfirmed ?.
Any help much appriciated


texts: Why isn't the description field synchronized at different Electrum wallet?

texts:
I use Electrum as my BitCoin wallet, and install it on both home PC and office PC.

I fill in "Description" field and send some Bitcoin on the office PC BitCoin wallet, it's OK.

The Electrum wallet on home PC can display the record except "Description" field, why?

1:  Is "Description" field  only for local record on Electrum wallet ?

2:  Doesn't a Bitcoin transaction record incude "Description" field?

Image 1

Image 2


texts: Bitcoin transaction unconfirmed, while way past expected processing time

texts:
I have started a transaction from "wallet A" at 2017-06-14 11:51:40 with

  Fees 0.00066328 BTC,
  Fee per byte 293.487 sat/B

Which is not yet confirmed over 8 hours later.
I have a second transaction from "wallet B" at 2017-06-14 18:08:25 with

  Fees 0.000599 BTC,
  Fee per byte 265.044 sat/B

Which was started almost 8 hours later than the first, with less Satoshi per byte and was confirmed within approx 1 hour.

How can the first transaction, with a higher fee not be processed, while the second one is? I know I didn't choose the highest fee, but the selected fee should have processed the transaction within 3 blocks, which was supposed to be within 60 minutes according to https://bitcoinfees.21.co/.

Edit:

I do have a past unconfirmed transaction, for which I put a way too low transaction fee, on that wallet. If there is a previous unconfirmed transaction, does that mean the next transactions will wait for the unconfirmed transaction to complete? This will never happen...


texts: How to take advantage of the free transaction relay policy?

texts:
I have about 0.027 BTC total, spread over 272 transactions.

Was going to send them to someone, and then the transaction fees hit me:  0.0245 BTC.  This agrees with the answer to this question -- (272 txns * 180 bytes each is 49 kBytes, or 0.0005 BTC per transaction).

Then I found out about the free transaction relay policy here, which looks like it will bring things down to a more reasonable 0.004 BTC.

I'm not understanding the mechanics of setting this up, though.  I can probably figure out how to do the following for the Eligius miner (I'm using the Bitcoin client with QT 4.8.3):

 Add the command-line parameter: -addnode=173.242.112.53

But the rest of the mechanics, I'm not sure.  Specifically:

How do I "broadcast the transaction to it"?  Can I do this within the Bitcoin client?
Does the person to whom I'm sending the BTC also need to add this same node?
Do I have to specify anything else within the transaction?

My goal would be to empty my wallet of all of these tiny transactions with this reduced fee.

Edit1: Is it possible to add node 173.242.112.53 using Electrum or one of the other clients?


texts: Installing Bitcoin Core On Raspbian with apt-get

texts:
Is it possible to install Bitcoin Core on Raspbian OS with just apt-get?

I tried adding the Bitcoin repo using:

sudo add-apt-repository ppa:bitcoin/bitcoin

and I get:

sudo add-apt-repository ppa:bitcoin/bitcoin
Traceback (most recent call last):
  File "/usr/bin/add-apt-repository", line 95, in <module>
    sp = SoftwareProperties(options=options)
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 109, in __init__
    self.reload_sourceslist()
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 599, in reload_sourceslist
    self.distro.get_sources(self.sourceslist)
  File "/usr/lib/python3/dist-packages/aptsources/distro.py", line 93, in get_sources
    (self.id, self.codename))
aptsources.distro.NoDistroTemplateException: Error: could not find a distribution template for Raspbian/buster


texts: What is the "silk road" and what does it have to do with bitcoin?

texts: I have read a lot about the silk road and I am still unsure what it is. I went to http://silkroadmarket.org but it just says that the site is down.


texts: Algorithm of checking whether an element is present in a merkle tree

texts: I've read and watch about merkle trees but can't figure out how to implement is_present(element) method. Explainations and links are accepted.


texts: My wallet doesn't show a confirmed transaction

texts:
Someone sent me Bitcoin payment but when I check my wallet nothing appears. On the blockchain, the transaction is already confirmed.

I use archived address.


texts: The "listtransactions" method does not display everything, errors with downloading and connection the block(s)

texts:
Not so long ago I started working with Bitcoin Node, I use RPC to receive payment from the site.
For a long time, there were no problems. Recently, he began to behave strangely.
1. Correct work
Output Errors from logs

debug.log

socket send error Broken pipe (32)
socket recv error Connection reset by peer (104)
Pre-allocating up to position 0x800000 in rev02310.dat
ping timeout: 1200.004205s
Timeout downloading block 00000000000000000000ef57678063c22a6e65c7d908fb12136bab2344ff3139 from peer=455976, disconnecting
ERROR: AcceptBlockHeader: prev block not found
ERROR: ProcessNewBlock: AcceptBlock FAILED (prev-blk-not-found (code 0))
ERROR: AcceptBlockHeader: Consensus::ContextualCheckBlockHeader: 000000000000014219120d5167a4281437fc379129d4ba6f6e956ca1db77f5fa, bad-diffbits, incorrect proof of work (code 16)

What is he trying to connect to? Mainnet?
Why was the block not found?

What could it be? And how can this be resolved?
2. Method does not display all transactions
bitcoin-cli getwalletinfo shows that I have 1537 transactions.
According to the documentation, my script application executes the RPC method listtransactions "*" 0 100 in a loop, increasing offset and writing to the MySQL database. The problem is that 3 transactions were lost, and they are not displayed by the method listtransactions. Instead of 1537 records in the MySQL database, I have 1534 records, it is not great.
How can this happen? Has anyone had a similar problem?
PS: Bitcoin Node 0.19.0.1.Sorry for my english(


texts: How to produce a p2wsh transaction with bitcoin-cli?

texts: With the impending adoption of segregated witness, users reliant on the bitcoin-cli API would require to reconstruct new methods to re-produce more efficient transactions. Is there some guide out there to learn how to produce a p2wsh transaction based off a conventional p2sh transaction?


texts: Wouldn't it be profitable to make an ASIC capable of calculating private keys?

texts:
Just looking at vanitygen-plus (currently supporting almost one-hundred crypto-currencies) do its stuff, and it is capable of over 548,990 keys/sec on my CPU alone.

Well developed ASIC is several orders of magnitude faster than my CPU, wouldn't it be profitable for a company with the resources to do so to develop such a key miner, even if it is a one-off?

The reward (actually, theft) is access to the private keys of any address. Surely the development costs are not so prohibitive for ASIC as they are for general-purpose CPU's?

Future developments in this area seem like the most realistic threat to crypto-currency security so far.


texts: Updating old BitCoin-QT Core client V0.7 - 2017 Approach?

texts:
I have an old "BitCoin-QT" Core client at version 'V0.7 2-beta' - that is far out of date re Synching. (That client says the program uses Qt version 4.8.4, incase that is useful too).
It was a ‘Full Node’ setup back then, cos that was the only option technology wise.

Am keen to get the client / block updated, so I can go shopping ;-).

Been reading the latest Coinbase “Bitcoin Core 0.15.0.1” release info (Oct 2017) - extract below from the Release Notes : “Note that the block database format also changed in version 0.8.0 and there is no automatic upgrade code from before version 0.8 to version 0.15.0. Upgrading directly from 0.7.x and earlier without redownloading the blockchain is not supported. However, as usual, old wallet versions are still supported”.

Is that text meaning:
(i) I have to separately go get the large blockchain file myself prior to the latest Core Client version install ?
OR
(ii) The latest client version will know to go get that latest blockchain / format and download for me natively itself ?

Assuming its the first point :

Where can I get / torrent the latest compatible blockchain ? been looking and they are from years ago.
Been reading conflicting information about my upgrade scenario (from V0.7 2-beta Core client to V0.15.0.1) with regard to the "bootstrap" ie hearing "this is not the way to go nowadays with the new technology". This was from a few years back. Been generally reading that this approach is not supported nor updated anymore, true?
Are there more detailed '****Release Notes****' against the Coinbase “Bitcoin Core 0.15.0.1” ? I've been looking. This paragraph quoted above is all I got as instruction for my scenario.

Luckily I've lots of disk space / ram / data allowance etc to make the upgrade happen on Mac OS - so am just needing confirmation on the steps so I only have to run this process once.

I’ll only be using the wallet every few months, I just want it for the Wallet.

Any advice here would be very much appreciated.


texts: How do you deploy a Bitcoin-Cash full node on a Cent OS 7 server?

texts:
I'm looking to compile it on CentOS 7.

Perhaps a guide.


texts: How does namecoin and other merge-mined coins prevent pre-mine attacks?

texts:
So, namecoin supports merged mining against bitcoin. My understanding of the merged mining protocol is that basically miners can use the primary coin's POW solution to solve the aux coin's block. It's possible for a primary coin POW solution to not be difficult enough for the primary coin, but be valid for the secondary coin.

However, given this, what would stop a malicious person from working on forging a set of primary blocks, such that they would meet the aux difficulty. They would set their blocks up to be a very high height so they have plenty of time to mine the blocks at the target difficulty (since they don't have enough power to do it in realtime of course). And then, when they need to control of the blockchain, they would submit all of these forged blocks at the proper time, messing up target block times and allowing them to possibly double spend..

How is this prevented?


texts: How can I calculate/estimate how quickly a machine can verify transactions on the blockchain?

texts:
If I have some machine with particular specs in mind (processor/memory/bandwidth), how can I estimate how quickly that node can download and verify transactions? In a quick search I wasn't able to find any numbers for verification speeds run on different machines, so that would be helpful too.

I have seen this question, but my question is more focused.

Update:

I found one bit of data about this: a lower bound of verification of last year's blockchain in about 20 days (projected, not tested). This amounts to about 170 transactions per second of verification.

More:
* [https://twitter.com/erickuhn19/status/1095553655086804993](Eric Kuhn) saying transaction verification is the main bottleneck.


texts: Generate Bitcoin Address JS Step-By-Step "Invalid Address" Error

texts:
I am following the process for bitcoin address creation as outlined in Mastering Bitcoin, however, when I try to reference this address in my bitcoin-cli, which is set to regtest, it responds with an invalid address error. I am attempting to write some JS to interact with my bitcoin node via the bitcoin-core package, but instead of just using all the built in commands, write some of the code myself to solidify my understanding.

I am using the following npm packages:

const EC = require('elliptic').ec;
const ec = new EC('secp256k1');
const bs58 = require('bs58')
const SHA256 = require("crypto-js/sha256");
const RIPEMD160 = require("crypto-js/ripemd160");

Here is my address creation function.

function createNewAddress() {
  // Get the private key
  const privateKey = ec.genKeyPair()
  // Get the public point from the private key
  const publicPoint = privateKey.getPublic();
  // Uncompressed public key
  const uncompressedPK = publicPoint.encode('hex');
  // SHA256 then RIPEMD160, aka HASH160
  const hashedPK = RIPEMD160(SHA256(uncompressedPK).toString()).toString();
  // Prepend the version, here we use 6F got the testnet (we are using regtest)
  const prependedPK = "6F"+hashedPK;
  // Calculate the checksum and take the first 4 btyes
  const checksum = SHA256(SHA256(prependedPK).toString()).toString().substring(0,9);
  // Append the checksum to the end
  const unencodedPK = prependedPK + checksum;
  // Base58Encode the unencodedPK
  const bytes = Buffer.from(unencodedPK, 'hex');
  const bitcoinAddress = bs58.encode(bytes);
  return (bitcoinAddress);
}

Here is a simple output:
mtURXDaisk6ustpeo7LuiZYje9yV31JhBN


texts: Is it possible to generate an invoice for my lnd without having a connection to my lnd?

texts:
Is it possible to set up a merchant site where:

The customer facing website generates valid lightning invoices, given some kind of master public key, that it gives users to pay
The actual lnd server is located on an entirely different server, and the front facing website works entirely without making any outbound RPC calls to the lnd server. The lnd server would be updating a backoffice database and would not have contact with the front facing website at all.

I would expect this to be possible, maybe by having the customer facing site and lnd both share the same seed that they use to generate preimages using. I have tried just making my own script to generate valid invoices using, but it seems like lnd still needs its AddInvoice RPC call for it to handle those invoices.

The parallel of course being BIP32, where we can put a public xpub key on the customer facing site, have the actual wallet software checking for payments on an entirely different server, and the 2 never having to talk to each other. In a worst case if an attacker took over the customer facing site, they'd only get my xpub for that week, since there are no private keys.


texts: Bitcoins unconfirmed even after double spend

texts:
I'm very new to bitcoin and recently bought 0.066 bitcoins and transferred them to my electrum wallet. I then transferred them to another wallet but I set the fee too low (40Sat/b) and it was stuck in blockchain for a few days before returning to my wallet. From there I resent the coins with a much higher fee (100Sat/b) and it said that I double spent the fees. After waiting for an hour this transaction also hadn't been confirmed so I used the increase fee tool in electrum and increased the fees yet again (260Sat/b). After waiting another 45-60 minutes it still hadn't confirmed. So, dumb me decided to increase the fees again and it all seemed to work except this time when I went to view the transaction on blockchain I was greeted with this...

"Transaction rejected by our node. Reason: Transaction double spends an input too many times DBOutput{outPoint=OutpointImpl{txIndex=223924437, txOutputN=5}, spending_outpoints=[OutpointImpl{txIndex=223932999, txOutputN=0}, OutpointImpl{txIndex=224715242, txOutputN=0}, OutpointImpl{txIndex=22473446"

This concerned me as on electrum it shows that the transaction is in the block and awaiting confirmation, yet it isn't according to blockchain. The previous attempts of raising the fees are still listed as awaiting confirmation on blockchain here: https://blockchain.info/tx-index/224734462
Any help would be greatly appreciated, my main concern is getting the bitcoins back and being able to transfer them to this wallet in a timely fashion, but if someone could just explain what is happening I would be very thankful!


texts: Confused about buy/sell definition in trades history

texts:
I'm looking at some trade history provided by the kraken.com API (formatting mine):

    Price         Volume         Time        Buy/sell Limit/market  Remarks
["7833.00000", "0.17400000", 1559721453.3446,   "s",      "l",        ""],
["7830.00000", "0.04984709", 1559721484.6288,   "b",      "m",        ""]

What I understood about trading so far:

Limit trades go on either side of the order book, at the limit set by the initiator. Buy orders go to the bid side and sell orders to the ask side. When a bid meets an ask a trade gets executed, up to the lowest amount from either side. Any remainder will remain on the order book until matched again.

Marked trades are executed near-instant by emptying the order book on the appropriate side until the order is filled.

As such, a trade is always both a buy and sell in the same time.

My questions: what is the exact definition of a buy/sell indication in the trade history? Is the sum of the volumes the total volume traded? Or should it be divided by 2?


texts:
So I don't understand how Tether (USDT) works. I hear two contradicting things about it. First, is that it is pegged to the dollar, plus or minus a few cents here and there. Second, that you can buy or sell freely from some other cryptos.

BUT, usually when lots of people are buying a crypto, it's price will go up. But tether seems to somehow decouple demand from price. I thought that was impossible?


texts:
In this forum post the poster (2112) writes:

It is my understanding that at least Eligius pool isn't a "honest node" and intentionally produces acausal blocks (or at least as close to acausal as they deem practical).

What is an acausal block? Or at least what did the poster mean by "acausal block". From reading the thread I get some idea that it is something to do with messing with the timestamp of the block but don't really understand it.
Perhaps this should be a separate question but does the block miner determine the timestamp that is recorded in that block?


texts: Would it be possible to retarget difficulty in real time?

texts:
Could the mining difficulty adjust in real time, not only when blocks are found?

(NOTE: Not asking about retargetting after every block but continuously as a function of time.)

I'm worried about how Bitcoin (and many other cryptos) change the difficulty. The basic idea is that the difficulty is adjusted every N blocks (N=2016 for Bitcoin and N=1 for Monero). That is, a difficulty can change only when a block is found. The problem is that if hashrate suddenly drops significantly, say 99%, then it would take 100x more time than normally to reach new lower difficulty. The drop could happen if the price of the coin drops and thus mining isn't anymore profitable. Network slows down and the price goes even more down and thus even more miners stop mining, and thus the coin might die. This seems like a very unstable system to me. I don't see much incentive for anyone to mine bitcoin if the price drops dramatically. The only incentive for some people to mine would be that they have lots of coins and they don't want the system to die. Not sure if this is enough.

To avoid this problem, could the difficulty adjust in real time, not only when blocks are found? That is, the difficulty requirement for a valid block would depend on the time it was found. The difficulty would decrease as a function of time, thus eventually a block will be found very easily. For instance, if 2 hours has passed since the last block, the difficulty could have already dropped to 1% of what it has been for the previous blocks.

The difficulty requirement of block N at time T would be a decreasing function of T and depends on the timestamps and difficulties of past blocks somehow. For instance, the difficulty could be a exponentially decaying function of time since the 10th last block and the mean difficulty of those 10 blocks. The difficulty of a mined block must be at least as great as given by this function in order for it to be valid. So the timestamp of a block becomes an important part of the block data.

Would this idea make sense? Is it implemented in any coin? Or is there some reason why it is not a problem that the difficulty adjusts when a block is found?


texts: Why do some addresses seem to send bitcoin to themselves?

texts:
When looking at block 630873, I noticed that some addresses seem to send BTC to themselves:

Am I misunderstanding the situation, or does 1A7tWftaGHohhGcJMVkkm4zAYnF53KjRnU send large sums of BTC to itself? If that is the case, why is it beneficial?


texts: What is the meaning of the term "full-node"?

texts:
There seem to be some different interpretations of what the term "full-node" implies. E.g. there seems to be some disagreement whether a pruned node is still a full-node.

So: What characteristics must be fulfilled to label a Bitcoin client as a full-node?


texts: Would it be possible to change the p2p protocol used by the bitcoin-clients without a hard-fork?

texts:
I had a look at https://en.bitcoin.it/wiki/Protocol_documentation where the p2p protocol is documented. Although it states incompleteness I thought it is a good starting point to understand the protocol.
To my initial understanding the protocol is based on c-structs that are directly sent over the wire. This makes implementations in other languages more complex.

Would it be possible to introduce a new protocol based on a well known communication method (for example JSON) and make a smooth transition between the protocols? For example with bridge nodes, which are using two protocols in a transition period?


texts: The price of coinbase Satoshies vs the price of mixed coins

texts:
I think that it is not pure fair that any of BTC Satoshies has the same price.
And what do you think about the recently mined coins that perfectly clear, or coins that has some grey history behind them?
So if I would like to buy or sell 1-st or 2-nd step-coins from coinbase transaction, those coins theoretically may be more expensive that coins from any exchange or any kind of a mixer.
It is interesting to know the opinion of community. Thank you!


texts: I was trying to transact BTC and the end receiver gave me an address. I couldn't afford the amount due to spreads on transactions so we lowered the amount, made a new address and i sent it but I accidentally sent it to the first address and not the second. What can I do? The BTC already left my account and I'm sure it won't reach theirs because the transaction was declined.


texts: What is the best way to implement withdrawal in online service?

texts:
Suppose we have a service, which holds user balance in Bitcoin.

How to implement withdrawal from bitcoin perspective?

Which RPC call to use? How to archive transaction to have a proof of sending money to user? How to prevent duplicate money send in corellation to SQL transaction?

The most important thing is to prevent dual-submission having in mind power loss at any time. So we should have a way to mark some money as "possible sended" + some way to check in future time if it really was succesfuly sended and stored in blockchain.

(note that I am not asking about security, ACID transaction itd. I am interested in a way to comunicate with wallet daemon service)


texts: Why does bitcoin core need to download the blockchain

texts: I understand that the blockchain is what keeps track of who has what coins and makes sure that everything is correct and secure, but why do I have to download it?  Isn't that where the miners come in?  Don't they keep track of the blockchain?


texts: Implementing an "ad-hoc-like network of payment channels" on top of Bitcoin network?

texts:
If we define an ad-hoc network as follows:

  "An ad hoc network is a network that is composed of individual devices
  communicating with each other directly." [1]

ad-hoc networks do not rely on routers or access points (as a point of failure) to avoid moving towards centralization. In case of using routers or access point, some kind of centralization is inherent.

With this definition of decentralization, can we implement an ad-hoc-like network between users connected by payment channels such that similar to ad-hoc network, they do not use any router to find and communicate each other?

Please note that I used term of ad-hoc-like network (instead of saying ad-hoc network) just to say that the target is removing any pre-existing infrastructure, such as routers from communications between users similar to an ad-hoc network.

[1] https://www.techopedia.com/definition/5868/ad-hoc-network


texts: Can you ever view your private keys on the TREZOR?

texts:
ON a TREZOR, is there a way to see the private key after it has been generated from the seed?  One that you could then import into another wallet manually.  I don't know that I would ever want to do that but I am just curious..

Thanks in advance!!!


texts:
In main.h (line 17) we have a constant MAX_SIZE

static const unsigned int MAX_SIZE = 0x02000000;

which in decimal format equals to 33554432 (32MB)

This constant is used to verify if the block passes the size limit in main.cpp (line 1154)

    bool CBlock::CheckBlock() const
    {
        // These are checks that are independent of context
        // that can be verified before saving an orphan block.

        // Size limits
        if (vtx.empty() || vtx.size() > MAX_SIZE || ::GetSerializeSize(*this, SER_DISK) > MAX_SIZE)
            return error("CheckBlock() : size limits failed");
        ...
     }

According to the git pull request history line 18 was added to main.h by Gavin Andresen:

static const unsigned int MAX_BLOCK_SIZE = 1000000;

https://github.com/bitcoin/bitcoin/blame/9d2174b6f5f3fac2463c7ebc2dbb9004b3740d23/main.h

this new constant appears to only be used on the BitcoinMiner() function on main.cpp

https://github.com/bitcoin/bitcoin/blame/9d2174b6f5f3fac2463c7ebc2dbb9004b3740d23/main.cpp#L2613

 if (nBlockSize + nTxSize >= MAX_BLOCK_SIZE - 10000)
     continue;

Apparently Satoshi believed that this would split the chain but this is only established on the mining node, not on a node that is just collecting new block and adding them to their chain.

What is the significance of this last line? How does this impact consensus? Where is the code limiting block size in the most current version of Bitcoin Core?


texts: $40 of peercoin mined per day: possible?

texts:
I have a friend who tells me she mines $40 worth of PPC per day per machine.  She has around 5  Cointerra ASIC servers working all day long.  One server is part of a pool.

I don't know enough about the rates.  But to me, it sounds very unlikely.

Is this, in fact, possible?


texts:
My question is if something exists to do the job in the opposite direction of miniscript.
Miniscript's intention is to help:

    ...writing (a subset of) Bitcoin Scripts in a structured way, enabling analysis, composition, generic signing and more

 So, for example, given the below Bitcoin Script:
OP_SIZE
32
OP_EQUAL
OP_IF
  OP_HASH160
  'dea3...'
  OP_EQUALVERIFY
  '301...'
OP_ELSE
  OP_CHECKLOCKTIMEVERIFY
  '19323434...'
  OP_DROP
  '303...'
OP_CHECKSIGVERIFY

  It would create something of this form (in JavaScript):
function canUnlock(preImageOrSig) {
    let pubKey1 = null;
    if (preImageOrSig.size() === 32) {
        if (hash(preImageOrSig) !== 'dea3...') {
            return false;
        }
        pubKey1 = '301...';
    } else {
        if (!checkLockTime('19323434...')) {
            return false;
        }
        pubKey1 = '303...';
    }
    if (!checkSignature(pubKey1, preImageOrSig)) {
        return false;
    }
    return true;
}

  The resulting JS code is NOT to be executed or compiled back to Bitcoin Script, but only to help a developer reason about the logic of the original Bitcoin Script.


texts: Will the 3TH KNC Neptune Miner still be profitable in 2014?

texts:
I am seriously considering making an investment and buying a 3TH miner. The problem is whether they will still be profitable by the time they arrive...

At today's has rate calculation of 707,408,283 it is expected to return 2.1328 BTC in a 24hr period.

The question is how realistic is this and does anyone own a miner that can confirm whether this profit forcast is achievable?

http://www.bitcoinx.com/profit/


texts: Where can I find a raw version of the Bitcoin blocks and other messages that are sent between the Bitcoin clients?


texts: Is "cryptofree.best" website a scam for mining? How does it works?

texts:
Few days ago someone introduced me website "cryptofree.best" and told me that you can collect Bitcoin in this website just by a few clicks on "Roll" button and by spending at least 1 hours/day. And tempted me that you can collect 1 BTC without spending any money in 3 months. But he pointed out that the rule of the above website is minimum 1 BTC for withdrawal. In that website if you invite an active user to the website then you will receive additional bitcoin as a reward/bonus.
He also tried to convince me by commenting that one of his friends had successfully cashed his money.
But how is that possible?  Are they misusing our smartphone/computer graphics remotely. If not why they are paying for free?

Are all website like "cryptofree.best" a scam for mining?

(I am not sure about tags. Feel free to edit.)


texts: Have there been any articles or presentations about Bitcoins in any influential or respected economic websites or perhaps interviews with notable economists?


texts:
With the recent rally and media attention, lots of new people joining the Bitcoin community.

A lot are asking:

I'm new to Bitcoin, how do I keep my bitcoins secure?

and if they aren't that's the first thing you should teach them.


texts: So I mined a block, but why would other nodes accept my mined block?

texts: When a miner finds a hash and is thus able to confirm a block of transactions, that miner will then broadcast the confirmation (block?) to the other Bitcoin nodes so that it can be added to the blockchain. My question is, what is the incentive for other nodes to accept this mined block, even if it is correct and checks out against older blocks? I ask because if the reward for mining blocks decreases over time, other nodes may selfishly not want to accept this miner's effort and prefer to figure it out on their own for a greater reward now than later.


texts: Hyperledger fabric vs Sawtooth lake which platform is appropriate for Supply chain management?

texts: I am planning to build supply chain management system with Blockchain. I have read many blog posts related to the topic, and eventually, I get Hyperledger as a right choice for Blockchain Network. but now I have two more option in that.Hyperlegder fabric & Sawtooth lake, now I am confused about the platform so can you please suggest me which platform is better for our Domain.


texts:
So determining the value of bitcoin is not the question at stake here.

Suppose there's a new bitcoin with a production algorithm that's tied to the feedback rule proposed by McCallum and adjusts according to a datafeed of Nominal GDP.
http://en.wikipedia.org/wiki/McCallum_rule

Part of the feedback rule linked above is the variable of Velocity. It's pretty straightforward to calculate it.
http://en.wikipedia.org/wiki/Velocity_of_money

There are other threads such as This one and This one too that ask similar questions, but debate over the actual solution.

Can anyone provide a straightforward answer? Velocity will have to be calculated in a way other than simple bitcoin days destroyed since the velocity figure from this calculation would be far too high if actors transfer between personal wallets.

edit: topic=46241.0 <-- thread on bitcointalk discussing velocity as well. (Won't let me link directly)


texts:
I have a question about an unspent transaction, we know that after some transactions we have a change address created by the main address, now imagine that Bob mined 6 BTC, now he transferred 2 of the two Alice and now in Bob's change address there is 4 BTC and they are unspent, now the question is that if I try to get unspent transaction of the main wallet with bitcoin core that I imported the address of Bob's main wallet, will it show me 4 BTC? or it can show if I try to get with child address?
Another question is that, is there any way to find a parent or main wallet, child keies?


texts: Bitcoin fund disappeared from my Mycellium account

texts:
I've recently made a purchase of some BTC through KuCoin. Transaction was approved and I then proceeded to transfer that money to my Mycelium account. 1Cht7fCGg7Kw2m5qAtRyrx7s9AjstGkX13 (transaction made through blockchain).
The funds were reflected on my app on IOS, but the app kept crashing whenever I tried to look at the transactions. So I deleted it and installed it again. After entering the seed words again my balance now appears to be zero. I don't understand what happened. I tried downloading electrum and entering the seed words there but my BTC are not reflected. I would very much appreciated if I can get some help. Thanks


texts: let's say I run a simple race attack (say in a restaurant). I transfer BTC to the restaurant but seconds before (or after) I send the very same coins to myself. To make this deal more likely for myself I assign a much higher fee to the transaction loop for myself. How common are such race attacks? I don't think the restaurant can wait like 6 blocks before they accept my payment. I would be most happy if you can point me to papers, stats, etc. Or is there a big gap in my logic?


texts: Why is not possible for a hacker to intercept the hashes calculated by a miner, and send it all himself as if he was a miner?

texts:
(I tried to make a more specific question, but is a bit confusing to me. Sorry.)
When a miner calculate a hash, where exactly does he send to in order to validate it? To all the nodes in the network?
Which protocol does it use to send this hashes? For example, HTTPS requires a trusted third party to sign server-side digital certificates, but there is no "server-side" in a decentralized network.
Why is not possible for a hacker to intercept all the hashes been sent by a miner or pool, and send it all himself as if he was a miner?


texts:
I created a Bitcoin account back in 2014, but my computer crashed a couple of year ago and I don't remember which firm or site I did it through. Not sure if that even matters. I do have the Wallet Name, Wallet Address and Wallet Key, but having difficulty using the data to access my old wallet in my new Coinbase acct. Please help!

Thanks.


texts:
I used to mine bitcoins and stopped about two years ago. At that time I was using Bitcoin-QT 0.8.5 Beta. The computer has been powered off since then, and my wallet.dat is still on that computer.

Can I still use that version, or do I have to upgrade to the latest Bitcoin Core? Besides backing up my wallet, should I do anything in preparation before I reconnect the old computer to the Internet, or before upgrading software? It says the wallet is out of sync and the block is 95 weeks behind.

Any guidance will be appreciated.

Thanks.


texts: How can I measure the total hashing power of the Bitcoin network?

texts: Is there a way to measure what is the total hashing power of the Bitcoin network at a given time? For pooled mining it isn't a problem - one can rely on statistics provided by the pool (assuming one can trust them), but what about people solo-mining?


texts: Solo Mining with Diablo-D3 Miner and Stratum

texts:
I'm using Diablo-D3 Miner to solo mine for a personal project. I setup Diablo-D3 Miner on my machine but since I do not want to download the entire blockchain (currently, over 200 GB) I decided to go with a "solo mining pool" known as ckpool. The issue is that they use the new stratum+tcp protocol and as far as I can tell Diablo-D3 is using the old http protocol. If I try connecting with http I get error: Cannot connect to solo.ckpool.org: Unexpected end of file from server

To resolve this issue, I tried using stratum-proxy to bridge the gap between http and stratum+tcp however in Eclipse console I'm observing the following message:

ERROR: Cannot connect to 127.0.0.1: Unexpected end of file from server

I'm aware that Diablo-D3 is no longer being maintained and that there are other solutions available (such as cgminer) which are both faster and more up to date. However, I am using this for a personal project and I'm only proficient in Java so I need to get Diablo-D3 (or something equivalent written in Java) to work.

Thanks


texts: Is "Proof-of-work" a subset of "Byzantine fault tolerance (BFT)"?

texts:
Can we say that Proof-of-work is a type of Byzantine fault tolerance (BFT) ? In other words, is PoW a subset of BFT ? Or they are two different categories?

Please note that there is a similar question here (BFT VS Bitcoin PoW VS PBFT) but without any answer.


texts:
I have experienced 51% attack after launching a new altcoin last month.

While i mined only 100 blocks using coin-cli generate 1, i noticed somebody already mined 2000 blocks within minutes attacking my network. I was running 2 nodes (without wallet) and 1 node (with wallet installed) in Ubuntu server.

Why would the attacker target new cryptocurrencies? Is he after coins?
What changes in the code i have to implement to prevent the 51% attack?

My altcoin is based on scrypt (litecoin), Block generation time is 10 minutes/hour, Coin maturity 100 blocks, with parameters almost same as bitcoin.


texts:
At the moment I have ONE linux server acting as the "APP" server for bitcoind/p2pool applications and another linux server with nginx proxying web traffic from the APP server, while behind CloudFlare.

What would be the proper way to scale out p2pool in this scenario? My thoughts were:

Create a cloud load balancer for the APP servers
Take a server snapshot of my single APP server
Spin up 2 more servers from that server snapshot and place them behind the load balancer
Update the DNS to point to the floating IP of the load balancer

Is this the proper way to scale up p2pool ?


texts: can I run bitcoin core with public key only

texts: I'm looking a way for secure setup of web site that accepts bitcoin payments. Ideally I'd like to create wallet off-site and be able to deploy bitcoin core online with public key only that I believe should be enough to generate new addresses and watch for incoming payments


texts: Does anyone have any hard data on bitcoin price fluctuations in relation to time of day and/or week?


texts: How do hardware wallets integrate with software clients/nodes?

texts:
It isn't clear to me how hardware wallets interact with software clients. Is there a standard defined for this? Is it similar to signing on an offline computer and then transmitting a signed message via a different online computer? Or (I hope not) do software authors have to write support for individual hardware wallets?

The tightest integration would be from the last option, but I'm wondering if there is a more manual approach similar to the "sign on the offline computer" workflow.


texts:
We all know that mining is supposed to keep the Bitcoin system secure. However, difficulty has risen so much that costs for power currently outstrip possible revenue for mining for a large portion of hardware - not only CPUs, but also many GPUs. Essentially for everything but specially built mining rigs.

That is, if you don't take transaction fees into account. Are they already high enough to support mining? Or are mining rigs going to be enough to keep Bitcoin secure?

edit: the question is about the current situation, not some arbitrary point in the future.


texts: In Ripple, when an IOU is defaulted upon, who gets hurt?

texts:
Let's say there are five people.

  Alice <-> Bob <-> Charlie <-> David <-> Eve

Each of them trusts the person next to them. For instance, Charlie trusts Bob and David, but not Alice or Eve.

Alice run a donut shop. One day, Eve comes in and asks to buy a donut. Eve creates an IOU, then uses the web of trust to resolve it. Eve leaves with the donut.

Eve then flees the country. Complicating the situation, David is broke, and was relying on Eve's IOU to pay Charlie.

Who gets hurt in this situation?


texts: Why would I trust a cryptocurrency that allow only 3 transactions/s?

texts:
I noticed that the recent blocks usually includes about 2k transactions with is almost the upper limit (max. 1 MB per block). From this I can see that bitcoin would never allow more than 2000 / 10 * 60 = 3.5 transactions per second which is far below other money services such as PayPal or any credit card company.

Because the 1 Mb limit is already reached in most blocks (in 2017), I can conclude the bitcoin ecosystem is already fully saturated in terms of transactions per minutes so it cannot expand further more.

Why should I trust bitcoins and invest my money on it with such considerations? Lots of people believe in bitcoins and put their money on it despite what I mentioned above.

I know bitcoin is a living ecosystem and the question of increasing the block size to 10 Mb has already emerged. Unfortunately performing any change to such fundamental build block of the system would have an enormous impact on its economy so may be never accepted by the community to make any change to the core code.


texts: Why raw Bitcoin transaction are in hex format?

texts: Why are Bitcoin raw transactions in hexadecimal format? I am looking for scientific articles / books on this topic and I can't find anything, so my question is: why are they in hexadecimal and can there be any article on this topic?


texts: How the BTC-e could dive to 102 points (from 700) and the recover back to 700

texts:
At around 10.00AM of 10th Feb, BTC-e had hit the low level of 102 USD/BTC from 700 USD half hour before.

How is it possible at all? And even after such a big dip, how did the market recover and survive?


texts: What is "trickling" in terms of bitcoin?

texts:
In the Bitcoin (0.10.0) source code I'm coming across the term "trickle".
Could someone please give short but accurate explanations on following instances and tell what they're used for?

bool fSendTrickle
bool fTrickleWait
CNode* pnodeTrickle ?

What is the general idea behind "trickling"?


texts: Can I ignore the blocks directory for time machine backups on OSX?

texts: After installing Bitcoin-QT I have over 40GB of files in the ~/Library/Application Support/Bitcoin. It seems that the most important file there is wallet.dat. Does it mean that I can exclude from time machine backups the ~/Library/Application Support/Bitcoin/blocks subdirectory to reduce the backup footprint? Will the bitcoin client download again those files in case of backup restoration without this subdirectory?


texts: How does the variable length integer work?

texts:
I'm trying to write a script that constructs a serialized bitcoin transaction from scratch.

But when it comes to the number of inputs, the field is a variable length integer.

It's typically only 1 byte (2 characters) in length and you do not have to do anything with it, because bitcoin transactions rarely have more than 0xFE (253) inputs.

But what happens when there are more than 253 inputs and the size of the field has to increase to accommodate it?

How would you put a count of 256 inputs in to this field?

https://en.bitcoin.it/wiki/Protocol_documentation#Variable_length_integer


texts: Electrum wallet is showing not enough fund

texts: My electrum wallet presently have 0.0047BTC. i'm trying to send 0.001btc to another wallet but it says not enough fund. Any limitations i need to know?


texts: Is access to mining the only obstacle to centralised bitcoin-like currency?

texts:
Considering the value of bitcoin beside dollars there seems to be so many applications where a centralised bitcoin-like system may be ideal for internal accountancy and transfers, especially among micro financial institutions.

Parsing a blockchain gives an overview of entire network.

If mining was restricted to only specific people what other obstacles are there for "private" use of Bitcoin clone?

Are there any commercial or opensource entities doing this?


texts: Bitminter - no rewards when more work was done?


texts: Why should retailers prefer bitcoin over other cryptocurrencies that have shorter confirmation time?

texts:
Considering that,

waiting 10 minutes for confirmation is too long in the retail world;
"zero confirmations" will become more risky once bitcoin popularity is high enough and people come up with services (automatic scripts) that try to do massive double spending,

why should retailers consider bitcoin over other cryptocurrencies that have shorter confirmation time, and therefore less potential risk?


texts: How can multifactor authentication be used when there needs to be two people with access?

texts:
For a business account at a Bitcoin exchange, either of two people need to be able to send bitcoins or withdraw.  This account will be configured with two-factor authentication.

How can two of the business' staff, located in different offices, each have access to the account?

The exchange specifically will be with BitFloor using Google Authenticator OTP, but the same question would apply for using Mt. Gox, with Yubikey, for instance.


texts: Will general non-standard transactions ever be allowed?

texts:
To the best of my knowledge, currently "Satoshi" client relays and most pools accept only standard (transfer or generation) transactions. Besides, community is working on M-of-N transaction type. Adding non-standard transaction to the blockchain is nowadays pretty problematic.

While currently enabling arbitrary scripts in transactions could be disastrous due to possible bugs in code (or in the script system itself), I wonder if it is planned to allow arbitrary transactions somewhere in the future, or will most of the network always be restricted to some set of "good" transaction templates?


texts: Block explorer with testnet raw hex data

texts:
Blockchain.info allows you to look at the raw hex of a transaction. But it doesn't have testnet functionality. Blockexplorer allows you to look at testnet, but I can't find a way to show the hex dump.

Any solutions?


texts: If the bitcoin address changes every time, why there is more than one transaction for an address in the ledger?

texts: I was checking a random address in blockchain.com, there are alot of transactions that is done over this address. While in the website it is mentioned that the address is changing everytime! So it means that every address should hold at most one transaction!


texts: What is the function of the payload_checksum field in the Bitcoin protocol

texts: According to the protocol specification at the Bitcoin wiki, each message header includes the  first 4 bytes of sha256(sha256(payload) as a packet checksum. I suppose this checksum is used for packet validation, but I do not see any benefit of this, as Bitcoin utilizes TCP which already has (as far as I know) full protection from lost and damaged  packets. So... why this checksum? Is it to maintain compatibility for future UDP clients?


texts: Can the blk0001.dat and blk0002.dat files be deleted?

texts:
I have a Bitcoin installation on an SD card, and the blockchain files (blk0001.dat specifically) take up nearly 4 GB of disk space.

Can the blk0001.dat and blk0002.dat files be safely deleted to free up space on my SD card? Will the blockchain just be downloaded again next time I run my bitcoin client?


texts: How long until an Antminer S9 becomes obsolete and should be replaced?

texts:
I'm currently considering the purchase of a few Antminer S9 13.5 THs and I'd like to have an idea of how long I could (or should) plan to use one before replacing it with a newer model.

I've seen some forums suggest 8-12 months, while others suggest it might be as long as 2 years.

Clearly, a part of the answer is based how long I can squeeze a profit out of each machine. In terms of major costs, my local electricity cost is $USD 0.08 / kWh and I will purchase the units directly from the manufacturer (so around $USD 2,320 + tx + shipping).

I understand there are many more variables, like how much faster future miners become, how fast the difficulty rate increases, BTC pricing etc, but I'd appreciate any general guidelines or wisdom you can share. Cheers!


texts:
I got this error when I have tried to compile on lubuntu 16.04

34: error: expected ‘)’ before ‘host_16bits’
inline uint16_t htole16(uint16_t host_16bits)

using clion, is there any guide on how to debug on linux using clion?


texts: What Ripple API libraries are available?

texts: I am wondering, what libraries are out there for communicating with Ripple through its API (either websocket or JSON RPC)?


texts: What programming language should I learn to create a new altcoin?

texts:
I've been wondering. What programming language is needed to develop and maintain an altcoin? Because I've been thinking to try creating my own altcoin.

I've seen a lot of services to develop an altcoin for certain amount of money. I could pay for it, but I prefer not to since it would be boring as hell to just do that and there's simply nothing that I can be proud of.

I've seen a step by step guide, forking from Litecoin. But I kinda want to do it blindly. (Meaning doing something that I don't understand at all).

I've learned Java and VB but I don't think it's even used a single bit in Cryptocurrency.


texts:
Reason - Due to unconfirmed inputs.
Can someone please explain what this means and could the sender do this intentionally. In other words to scam someone.


texts: I had a couple of bitcoins in a iPhone “Bity” app wallet.  I hadn’t accessed that wallet in a few years. After hearing the recent bitcoin value, I decided to get into my wallet to see how many bitcoins I have. Well the Bity app is gone and so is my private key.  I can only “watch” my bitcoins with my public key.  Is it possible to import a private key that’s attached to those bitcoins?


texts:
How does one log all an Antminer's statistics (temperature, hashrate, etc.) to a file?

I can log in to an Antminer via SSH, so I should be able to turn on some option for cgminer to log everything, no?


texts: unknown output script in a sample bitcoin pcap file

texts:
I start working on bitcoin protocol to extract output addresses from scripts in tx structures. Now in can produce some valid bitcoin address but some scripts are not familiar in op_code lists introduced in bitcoin wiki(script).

for example, the hex stream value of output script in first tx structure of my sample pcap is like this:

410498361908359fec5adaa624428484e7d117f36f811c7c471f4f1c7dd8184c20b32f0e2590c8d70906ebd585da2ae14ea942e4088891139379b434a26173754750ac

and no op_code is present with 0x41 value.

can anyone explain this matter?


texts:
As the wiki article says,

  Given just those fields, people would frequently generate the exact
  same sequence of hashes as each other and the fastest CPU would almost
  always win. However, it is (nearly) impossible for two people to have
  the same Merkle root because the first transaction in your block is a
  generation "sent" to one of your unique Bitcoin addresses.]1

Who generates the coinbase transaction?


texts: Can a miner's hashrate be derived from shares submitted at a given difficulty?

texts: Trying to generate useful stats about client activity in a pool. If a quantity of submitted (timestamped) shares is known, and the difficulty of each share is known, how can the client's aggregate hashrate be determined?


texts: I made a transaction on March 13th, transferring .88 BTC from my desktop wallet to another account. I have a Mac and am using Bitcoin-Qt version v0.8.1-beta. The transaction did not go through, my wallet is "out of sync", and I do not have the .88 BTC in my wallet anymore. I have scoured the internet trying to solve this problem and have not found anything yet. Any help is MUCH appreciated!


texts: I recently downloaded the Armory Wallet for my Mac. It appears to work great, but is there any way I can purchase Bitcoins via an exchange on the wallet interface itself? If not, what should I do?


texts:
Can anyone alter the data after OP_return?

My question needs to have more characters, so I insert an example, that doesn't hurt:

"vout" : [
    {
        "value" : 0.00000000,
        "n" : 0,
        "scriptPubKey" : {
            "asm" : "OP_RETURN 636861726c6579206c6f766573206865696469",
            "hex" : "6a13636861726c6579206c6f766573206865696469",
            "type" : "nulldata"
        }
    }
],


texts: How to properly update a forked masternode coin

texts:
I have a BitcoinCore/Dash Fork I've gotten to run successfully.  I have it mining correctly in the Wallet, also have 1 Full node, and 2 master nodes setup.  All have been working perfectly fine, I ended up mining up past 1000 block.  The problem I am running into mentally is how do I properly update the core code and push out updates without disrupting the whole network?  How does the network know that my node I push code to, is the correct one it should be receiving updates from?

Also, is my first "full node" (which is just a node, not an actual masternode) ever goes down, does the network still continue forward?  When I bring my full node backonline with new updates does it just resync with the other nodes for the blockchain?

The reason why I ask this is because I just tried to do an update and I had taken down my 2 masternodes and my full node, plus my QT wallet, then when I went to update everything and get back online everything got stuck in a "out of sync" since 4 hours had past.


texts: To create a channel on the Lightning Network, do you have to execute an actual transaction?

texts: I'm trying to better understand the Lightning Network.  I was reading this article -- https://medium.com/coinmonks/lightning-network-how-does-it-work-ceeeda8ad21e .  My question is, when two parties create a channel and one or both commit funds to that channel, is the committing of those funds an actual transaction on the Bitcoin network?  That is, can the two parties involved only start using the channel when that transaction has been settled on the Bitcoin network?


texts: Account system is deprecated. Now, how can we set a "from account" when using the "sendmany" function?

texts:
Currently I have been faced with a problem from the update of Bitcoin Core. As you may know, in the recent update, Bitcoin Core deprecated the concept of account belonging to each node. Hence, I cannot set the parameter of 'from account' or 'from address' for the coin flow tracking any longer, when I use the Bitcoin Core API methods (i.e. sendmany, sendfrom, sendtoaddress) to control Bitcoin cryptocurrency assets. The problem stems from here.
I have been implementing a service as a sort of Bitcoin escrow system, operating an individual Bitcoin Core node within it. Each user of my service takes each address, and the user addresses belong to each individual account, and the accounts belong to the Bitcoin Core node of my service. But, as the account got deprecated in the recent update, now I may not specify a certain user address under my service node and manage the asset therein. The problem is, for instance, when I call sendmany method to send BTC 1 out of my service node, the asset distributed in the user addresses of my service would be randomly reducedand the total reduction volume should be BTC 1. In other words, I cannot extract the BTC 1 certainly from the targeted user address whose owner should have used our service to pay for something worth BTC 1, and the burden of BTC outflow shall be shared for all. Furthermore, as the sendfrom method has been also deprecated, I cannot specify a user of my service to manage his or her BTC asset stored in the given wallet address.
The solution I'm considering now─and temporarily using─is, setting a database system to manage the inflow and outflow of the node and the user asset. i.e., I can specify and manage each user and his or her asset in the wallet address only via the database (e.g. mySQL), and when another participant out of my service finds our small service network, it would only be identified as a single node, controlling an asset package stored in one storage. I mean, my service node shall be a minimized Bitcoin bank for the service.
However, I want to ask your help, for me to find another way to identify each user and manage the asset in terms of each address. I don't want to let my little database be the only dominator to manage the user information, as the implementation of such database might result in a serious security problem. I want to identify each user, the address, and the existing asset therein only via Bitcoin Core protocol and the API defined in RPC.

Please give me some advice if you have any.

Sincerely,


texts: One Code, Two Different Compilations (One Dirty Version of BitCoin)

texts:
Right now i'm developing an AltCoin based on BitCoin Cash.

I have one code, which i compiled in two different servers (A and B).

The A server, compiles the Bitcoin as "Bitcoin ABC version v0.16.3.0--g2vdf00a68", but the B server compiles the Bitcoin as "Bitcoin ABC version v0.16.3.0--dirty".

Right now the nodes are visible as peers, between the servers.
But the mining has been impossible.

I think it may be related with the difference between versions, on the compilation of the SAME CODE.

Here it's the compilation output of the dirty version:

https://pastebin.com/P8A2Ydk3


texts:
As of April 16 2018, there have been 518563 blocks (e.g. https://blockexplorer.com/api/status?q=getBlockCount). Is anyone aware of a way to get the number of transactions in each of those 518563 blocks?

There is a page that provides the average per day of the number of transactions per block (e.g. https://blockchain.info/charts/n-transactions), but I want the raw data that went into those averages.

There is another page that provides the list of all blocks, and clicking on a block gives you the number of transactions in that block (https://blockchain.info/blocks), this is what I need, but I will have to click more than 0.5 million times.

Is anyone aware of a way to get the raw data of the number of transactions in each of all existing blocks?


texts: How can I programmatically use several different (isolated) wallets?

texts:
I want to use several different wallets (as if one wallet = one account), and want to make sure the spending and receiving activities are exclusive to one wallet at a time.

How can I interface with multiple wallets?  (through a program or script)
How can I access multiple wallets at the same time?


texts: Can you use bitcoin to transfer money from US to Japan and what would it cost for approximately $10,000 usd?


texts: As far as i know that online wallets as Blockchain.info is a Bitcoind instance that gives each user an Account and each account related to multiple addresses through JSON-RPC calls, how blockchain.info backup wallet of individual account ? i imagine that all accounts are stored in a single wallet.dat ! or does blockchain.info has wallet.dat for every account ?


texts:
A few days ago I transferred bitcoins from www.blockchain.info to the Bitcoin Core - Wallet, but the bitcoin did never arrive, I made a Request and the address was: 15Yw9RpFY28cN1fjwQPQfqvxjGg9TXRLmB then I send the bitcoin to that address from blockchain but they never arrived.
My Bitcoin Core - Wallet is still synchronising with the network, it is 3 years and 21 weeks behind, is this the problem they didn't arrive?

Thanks,


texts:
My experience with PHP is not the best, but it's good enough to learn and expand. I wish to create a Bitcoin eWallet for my website where it automatically creates a Bitcoin wallet for users. This wallet will also do other stuff, such as generate a new Bitcoin wallet every 24 hours or so.

I read through the running bitcoin but didn't understand much of it. I know many websites such as Blackmarket Reloaded have what I need but my website is no way related to drugs or that stuff, I'm just using their eWallet and escrow as an example of what I need.

I checked out many websites that provide APIs like this (such as StrongCoin) but all their APIs and files are too old or deleted.

How can I go to making this come true? Any steps?


texts: How to generate a native Segwit address and P2SH Segwit address from a standard WIF?

texts:
Can I have the steps to generate a native Segwit address from a standard WIF? And the steps to generate a P2SH Segwit address from the same WIF?

How do these two formats differ and why are there two? I've seen that the P2SH version is compatible with older clients, are native Segwit addresses not?


texts: What's relationship to each address other in Bitcoin Core?

texts:
I just made two and more address in Bitcoin Core wallet.

Is there any relationship to each address? Like based on seedphase? or Just literally making 'random' address?
If so, an attacker can hack the other address if knows one of private key?

Thank you for your answer.


texts: Can you mine more bitcoins on amazon aws than it would cost to operate the servers?

texts:
Read title.

Creating a soft of self sustainability if you will. It might not be possible?


texts: Is there a way to estimate the price based on the blockchain?

texts: Suppose I need a rough estimate of the current value of BTC in USD, is there anything in the blockchain that could be used for that? For example, is there some kind of correlation between block difficulty vs price, number of transaction vs price, etc?


texts: Importing 24 word mnemonic to bitcoin-qt

texts:
How can I import my 24 word mnemonic seed into bitcoin-qt?
I think that I will have to convert it to some other format but I don't know how to do that nor what format to use. BIP 39 does not work.


texts: The logic of exchange services of bitcoin

texts:
As we know,it takes at least 10mins to transfer bitcoin to other accounts.therefore I guess they actually don't transfer any bitcoins except when their users try sending to others they want.

So do you think what I guess is right?


texts:
It seems that some transactions, although having "prev_out" field in their "inputs", does not have "addr" in the "prev_out", i.e. they do not have input address. What is this kind of transactions for?

e.g. transaction hash: 38d4154f800cbbce0ac39772dd88d338424be21ba36ccb6a11110a029e6b5a1e


texts: Electrum server full node bitcoin core wallet- how to block all outside access?

texts:
i have read that with an EPS electrum server, other nodes in the network  can "ping" your port , i believe the port no. was 8333. How can I for sure and for any situation block such accesses? The EPS should be isolated, only interact with my full node and should not participate in any other communication within the network.

Can you please guide me through the steps which settings I should change, and where?

Thanks


texts: From what I understand (which is not much), private key is like id/password for your wallet. So lets say, I have random number generator and I generate random number, is it possible that generated number could be key to someone elses wallet?


texts: CPU Mining with a large EC2 cluster - worth the effort?

texts:
I'm relatively new to Bitcoin, and am playing around with pool mining for fun.

I have access to a fair amount of EC2 instances - c1.mediums - between 30 and 50 on a given day.

I already have the 'minerd' CPU miner working on a single instance, connecting to a mining pool service.

Two questions about this setup:

First, would running 50 c1.medium instances, each running 2 threads of 'minerd' at ~ 750 khash/sec/thread be worth it?

Second, I assume this type of mining is allowed in a pool against a single account, but maybe it's not? I am thinking the 50 instances would all work together to increase my account's work load, but I may be misunderstanding a fundamental part of Bitcoin mining.


texts: Is bitcoin just one long block chain or are there multiple chains?

texts: Is each block found just a link in the same long chain, or are there multiple chains?


texts: How to transfer bitcoins from one Currency to Another from Brazil

texts:
I want to send money from real BRL to euro EUR. I live in Brazil.

How can I use bitcoins for that? And How would I make the bitcoins available for the person to spend in Euros?

Thanks.


texts: Is the `addmultisignature` API call dependent on order of public keys in the array? Or is it lexicographically sorted?

texts:
Say Alice and Bob are part of a partnership business that accepts Bitcoin. They store all their main funds in cold storage until the end of 3 months, when they cash out and use a new address. This cold storage is in a single address.
Both Alice and Bob have full nodes, running Bitcoin Core. They use the console feature to generate a 2-of-2 P2SH multisig address, using addmultisignature.
They exchange each other's public keys, and input them as arguments.
If Alice used the following syntax:
addmultisignature 2 '[<alice's key>,<bob's key>]'
and Bob used:
addmultisignature 2 '[<bob's key>,<alice's key>]'
Will they end up with the script hash and address?
Follow up questions:
Can you give certain keys more "weighting" by specifying them more than once?
Does the same logic apply to SegWit (P2WSH) multisigs?


texts: Script to import multiple priv keys in Electrum

texts:
DuckDuckGo turns up nothing of interest. How to import multiple priv keys in Electrum from a file using Electrum console or shell script, for all derivable valid BTC addresses? (1,3,bc1)

Eventually I would like to pipe the output of one script directly into an import script.

The file is in format:

BTC Pattern: <pattern>
BTC Address: <bitcoin address beginning with one>
BTC Privkey: <bitcoin address beginning with five>
...


texts: How do I know when my mining GPU has been worn out?

texts:
How do I know for sure when my mining hardware (GPU in particular) has failed?

How can I be certain that my card is at fault and not my software or overclock settings?

  Example: On my rig one of my card's hashrates updates the hash/sec display very slowly and after about 5 minutes of mining phoenix miner will crash and refuse to start up a new instance.

Thanks


texts: Does calculating how many bitcoins I have take longer as time goes on?

texts: I have read that the blockchain is a series of transactions that record one person giving bitcoin to another.  Please correct me if this assumption is wrong as it is the basis for my question.  So, over time, doesn't it take an increasingly long time to figure out if you can accept Bitcoin from someone because you will have to go through every transaction in the history of the blockchain to validate that the person giving you Bitcoin does indeed have that Bitcoin in the first place?


texts: Can a Bitcoin address be traceable to a crypto exchange?

texts: If a Bitcoin address was created upon the opening of a Binance or Coinbase account, is there anything in the address itself, or its activity, that can give clues to whether it was in fact created on Binance or Coinbase? So that the tracer can approach that exchange and complain about that account's activity?


texts: How do I switch from MultiBit to Bitcoin-QT?

texts:
Okay, so I have seen the questions on how to go from Bitcoin Core to MultiBit, but I want to go the other way.

Really, I downloaded and started using the wrong wallet.  I wouldn't even mind MultiBit if it wasn't for that the default folder can't be moved (I dislike having a cluttered home folder) - I asked, and the location is hardcoded.  Considering I use the default clients for the altcoins, I'd rather go with Core.

I'd transfer my little funds to Bitcoin Core and suffer the fee, but I have less than the threshold (0.006 something).

Is there a way to make my wallet active in Bitcoin Core, preferably without tearing my hair out?  Or should I (groan) keep mining altcoins next winter (too hot out right now for my poor PC cranked up), build up my Bitcoin balance by exchange, then transfer wallets the easy way?

Details are appreciated.  Thanks.


texts: What was the intended benefit of truncating the Target?

texts:
I'm thinking about how the Target value is truncated to and later compared to the SHA-256hash of the Block Header.

Given that

The maximum target (lowest possible difficulty) is
0x00000000FFFF0000000000000000000000000000000000000000000000000000
and the current target is
0x00000000000004985C0000000000000000000000000000000000000000000000
                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (4bits * 32 = 128)
                                  This part is always zero due to truncation

Question:

Is it simply there to make coding and evaluation easier?
Does this make the mining operation faster (more efficient comparisons)?
Are the efficiencies of the previous bullet endian-specific?
Are there statistical benefits or drawbacks to making it non-zero? (fractionally easier to find a block?)

I haven't seen a thoughtful explanation of why the decision was made, and I don't want to infer anything on my own.