texts: How is the "N" in PPLNS chosen? 2xDiff appears to make no sense - OR - Why are Scrypt share difficulties off by a factor of 65536?

texts:
while my example in the following question is using the altcoin "Bitconnect", I believe it is actually a general question which fits here - if not, let me know.

I am struggling to understand PPLNS (I need to implement it in a pool). I know in general how the system works, but what is a mystery to me is where the N comes from.

I read on many places on the Internet that N = 2 * difficulty is a good value, and that this would mean that on average a miner will earn rewards from two blocks for the same shares.

However, it simply does not add up for me.

Practical example: BitConnect pool. Let's say BitConnect's difficulty is currently ~900,000.

An AntMiner L3+ submits a share at difficulty ~150,000 (which counts as a share value of 150,000 then) every ~15 seconds, so in 3 minutes, that one AntMiner has already filled the whole "N" of 900,000x2=1,800,000. That would, in reverse, mean that I would expect to mine a BitConnect block every 90 seconds on average, with one AntMiner, which is of course not true.

100 AntMiners running on our pool gave a share value of 230,000,000 in the last 5 minutes, which would have been more than 100 times the whole "N" already!

So something can't be right here, and I don't understand what. Should I not multiply the submitted share with the work difficulty? But then a small miner would get the same reward as a large one which makes no sense. Or is the whole Internet wrong about the 2*diff for "N", and that it's based on the assumption that it takes on average a value of shares equal to the difficulty to find a block? Doesn't sound likely.

On average, it takes 2^32 hashes to find a valid share at difficulty 1, right? And on average, it takes X shares to find a share at difficulty X, hence why you increase the difficulty at the pool for your miner if the miner is powerful (it will then less often submit a share), right...? But the last point starts to make less sense already, together with the fact that you need a share at difficulty Y to find a block if the currently coin block difficutly is Y... And the pool software counts a share with difficulty X the same as X shares with difficulty 1. At the end I'm left confused how it all works together and how I can arrive at a value for "N" which actually results in a miner getting on average two rewards for the same share...!

Please help me understand what is wrong.

EDIT: I found that all calculations differ from reality by a factor of 2^16. Then I found this: https://bitcoin.stackexchange.com/a/11816/62320
This would suggest that for Scrypt, pools use a scaled "share difficulty" value by exactly that factor, but the reported block difficulty would not be scaled. This would explain everything but it's the only place I found this on the Internet (and it would mean that I need different calculations depending on the algorithm I'm handling) - can anyone confirm this?


texts: What format is the time of a Bitcoin transaction stored in?

texts:
This may be a very simple question to answer, but I haven't been able to quickly find it.  Regardless, if you were to deconstruct a transaction in the blockchain, and pull out the time value of the transaction, what format is the time stamp in?

In other words, if you were to pull out the draw time value, how can I convert it to a meaningful value?


texts:
I'm implementing my own blockchain reader but I'm stuck validating transactions.

I can validate a common transaction checking the UTXO and executing both scripts, but... how do I validate generation transactions? AFAIK there's no flag that lets me detect generation so I can ignore the input.


texts: Recommendations on how to buy Bitcoins with limit orders

texts:
I live in the US, have US bank accounts, and would like to buy Bitcoins, but with limit orders, e.g. place a limit order for 1 BTC = US$500 or less, and wait for several weeks to see it fulfilled.

What are reasonable options for me?  I know that Mt. Gox offers such limit orders, but to get money to them requires expensive and time consuming international wire transfers.

An ideal solution would enable to me to place a limit order to buy Bitcoins with a transfer from my US bank account.  I can easily transfer USD from my US bank account with ACH or a US wire transfer.  However, I am open to any reasonable solutions.

Any suggestions are appreciated!


texts: Name of attack where you pay a high fee to block others

texts:
Is there a name for an attack where someone with a lot of capital makes loads of transactions with a high fee, just to prevent other transactions from taking place?
This seems like a moderately cheap way of preventing 99% of all transactions. Is this a real vulnerability, and if so what is its name?


texts: Is there any protection against receiver's address masquerading attack?

texts: How does one verify that the address of, say “Foodmart”, which the sales person is telling me to send the payment to is actually the address of “Foodmart” not that of that salesman himself? To be specific, how does the blockchain prevent address masquerading attacks?


texts: Does LN require an on-chain "emergency lane" to mitigate systemic risks?

texts: According to LN social slides, a fee market (in other word: "congested mempool", to my understanding) is good. But, there's systemic risks around penalty mechanism, so some sort of on-chain scaling (which looks like an emergency lane to my understanding) is still needed to mitigate them.


texts: Is it OK not to sort transactions at all?

texts:
According to Mastering Bitcoin. Mining - Transaction Age, Fees, and Priority, miners sort transactions, using special parameter, called priority, which looks like

Priority = Sum (Value of input * Input Age) / Transaction Size

If the priority is greater than 57,600,000, it means that transaction is high priority and it will be written in the first 50 kb.

The question is: Is priority really necessary? I mean, if I'm a miner and I have e.g. 1000 unconfirmed transactions, is it ok to randomly choose 100 transactions and put them into the block just as it is? Without sorting by priority or fees?

Will it work out or I'll get reject message or something?


texts: What kind of random numbers source does getnewaddress in Bitcoin Core API (bitcoind) uses?

texts: Is it an internal PRNG? Is it fed  from /dev/random or /dev/urandom? How secure is it? If I have a hardware (TRNG) plugged in feeding my /dev/random will this source of entropy get used by bitcoind?


texts: how to import my wallet from blockchain.info into bitcoin-qt?

texts:
I have read the related discussions about how to import a wallet and though they are close, the answers does not help with this problem so I'm asking it here and now.

I have my bitcoin public address which was given to me by blockchain website when i registered, and the secret 12 words passphrase, and the blockchain wallet ID and my password for blockchain website. I can't login to the blockchain website because it sends a 2FA key to an old email for which I lost my password a long time ago. I have been asking for blockchain support because I can easily prove I am the account owner but I got no answer so far.

So, I'm looking to solve this problem. I'm running Linux Mint and I would like to import by bitcoin wallet into bitcoin-qt client. I know I need to use importprivkey into the debug console but I don't know how to get my private key since I can't login to blockchain website.

Many thanks for any help.


texts: Why are my bitcoin transactions going to 2 addresses

texts:
Here is my transaction:
https://blockchain.info/tx/3ddd5a173a73fc82bb0e1eb4361b8c36eb65919e2bfb9ee78fe2c6b5ff3f2307

I only sent .003 BTC to 1 address (35iR3hnFqmkHswRm8PmZgTKxYm7GfucNZJ), but the transaction shows BTC being sent to 2 addresses. This is exactly what happened to me one month ago with another transaction:
https://blockchain.info/tx/672744cd9a355b908fbf256680726e96279c13a8c39770a30a472c25371c6798

Since you guys tend to be pretty cynical (meaning you're smart) I have attached a screenshot as proof that I did not try to send the transaction to 2 addresses.


texts: How can I find out if a transaction used a specific vout as its input?

texts:
I want to know if a certain output is spent. I am not using bitcoind, I do not have a gettxout RPC call available. How can I learn if a vout is referenced as an input somewhere in the blockchain or accepted mempool?

I don't mean just for my wallet, I want to know if an output has been spent on the network somewhere.


texts: Are there any online wallets available for Litecoin?

texts: Are there any litecoin wallets available on the internet right now? I have a mac and the mac version software is very confusing.


texts: How many bytes long should nSequence be?

texts:
When I look at the following raw transaction from: https://blockstream.info/tx/a175425ee2f3c01acc97ef32ab1082db14eaa94e5af4c54f02f3b01dec72558e?expand

020000000001018e5572ec1db0f3024fc5f45a4ea9ea14db8210ab32ef97cc1ac0f3e25e4275a100000000**00cf050000**01d2ddbc0000000000160014b82d832b2e5c0d80c771b06ce0da50fbccf12f3e0347304402204a54d94068512c22847cc07fa85f2b93feaf758411920a9b20ce9b85831e8aa5022005924cb82c331c5173e21477a4d8298eb25c0d967ace065b883455f2537c3d0a01004d632103f96d73ffe138690f032e97408af933a71782ad27a28df66a750b48c56b2d7fa96702cf05b275210304f332f50363cd01b679d9fb50fb8691fb0fb638737867bd02f06850c6191a2268ac00000000

When I parse it manually, specifically at this section: a100000000**00cf050000**01...

a1 is the last byte of the input tx (in little endian),

00000000 is the output index (4-bytes),

and at the end the 01 is the tx_out_count.

But that would make the sequence number 00cf050000, which is longer than 4 bytes? What am I missing here?


texts: How to migrate bitcoin node from one computer to another

texts:
In my old computer some addresses have bitcoin and it is showing on blockchain.

When i am trying to get balance of the same addresses in my new computer where i have synced bitcoin full node ,I surprised addresses showing zero balance.

I am very confused, how can i backup bitcoin wallet from old computer to another


texts: Will a Schnorr soft-fork introduce a new address format (i.e. not bech32)

texts: When we (hopefully) soft-fork to Schnorr signatures will the address be indistinguishable from bech32 addresses?


texts: How do i list my ICO token created on Stellar to an exchange?

texts: I believe stellar has a built in exchange called stellarterm for tokens created through their platform. My question is am I able to list my token on another exchanges or are we limited to only stellarterm?


texts: If bitcoincore.org goes down how can I access it? What can I do to help others access it?

texts: bitcoincore.org is a trusted resource for information on new Bitcoin Core releases and soft fork upgrades. How do I access it if it is taken offline? How can I help others access it if it is taken offline?


texts: How to configure a bitcoind instance solely designed to contribute to the network?

texts:
I'd like to run a headless bitcoind instance on a server, in order to contribute to the network. Are there any specific configuration options that are recommended for that purpose?

My intention was primarily to make the network more secure by providing one more "good" node, though since I'm not familiar with some of the maybe more subtle aspects of the protocol, I'd welcome advice on other ways a single node would or could contribute.

I was not necessarily planning to run a miner.


texts: binance on site data and api data doesnt match

texts:
When I collect say 1 minute historical kline data through the API, I see differente close times to what I see on the site checking the same time's candle. (I am matching data to UTC time that is not a factor here.)
Do you have any tips what might be the cause?


texts: Is it possible to spend partial amounts from a paper wallet?

texts:
Okay, so I create a paper wallet from blockchain.info and have it printed out with the public/private keys. Now I loaded it with some bitcoins. In my blockchain.info account it shows it as watch only.

Now my question is can I spend them partially or do I have to spend them in full by scanning the private key portion of the paper wallet?


texts: Why is it dangerous to hard fork the Bitcoin network?

texts:
In the blocksize debate it is often stated that hard forks are dangerous. This is sometimes supported by the claim that "people may lose money and must be protected". And that it's impossible to prepare for a hard fork in a few months.

What are the dangers of a hard fork?
How would people lose money due to a hard fork?
Why is it necessary to give more than a month time to prepare for a hard fork?


texts:
I have the issue that my node's synchronisation is very slow. I am 14 weeks behind and it estimates to take 12 weeks to get synced. The synchronisation rate per hour is only 0,01%.
I have a fast broadband connection and no other issues with this PC. It should be able to download the whole blockchain in a few hours. However, the average transfer rate is about 0,5 KB/s.
Any idea what the issue might be?
I am running v0.14.2 and the number of outgoing connections is 3.
I have already changed cache memory to 800 MB but that didn't change anything.


texts: Multisignature technology in bitcoin - math and code

texts: I am interested in the math and code behind bitcoin multisignature technology. I've been looking for actual code that creates a multisignature address/pub key, and verifies transactions/digital signatures; that can be executed in one go. I didn't find anything in bitcoin core maybe because I dont know where to look. Does anyone know where I can find the actual code that creates a multisignature adress and verifications. I would also like to know if there are any m of n schemes written in code and the math explanations behind adress /pub key creation and signature verification.


texts: How cryptocoin trade engine works? Is there any open source project available other than buttercoin. I want to build a simple trade engine in ruby on rails for cryptocoins. what are the essential parts needed other than API?


texts: Can I have one wallet for all types of coins?

texts: I am new to trading. I want to trade BTC, LTC and ETH. If I don't want to keep the coin on the trading website, do I need 3 wallets for my coins?


texts:
I am using this website for cloud mining cryptocurrency for free. I was reading about How the Cloud Mining/Hashing Works when I came to this point in which says

(Cloud SHA-256) SHA-256 algorithm, 1.0 GHS per 1.0 cloud instance owned.
(Cloud Scrypt) Scrypt algorithm, 1.0 MHS per 1.0 cloud instance owned.

Could you explain these points in an easy way so I can understand it?


texts:
I am trying to retrieve my private key by debugging the address that was used for sending bitcoins to my wallet in the Bitcoin Core App. However, when trying to import this private key in another app it does not recognise it.Do you know where the problem might be?
(Another thing is that I do not have enough space to sync my wallet, can this cause the issue?!) Thanks for help.


texts: How to read the asset quantity list of open asset protocol?

texts:
I'm studying open asset protocol, however I have no idea how to read asset quantity list.

The Open Assets Protocol documentation tells that data in marker output

0xac 0x02 0x00 0xe5 0x8e 0x26

means

The asset quantity list:
                                   - '0xac 0x02' means output 0 has an asset quantity of 300.
                                   - Output 1 is skipped and has an asset quantity of 0
                                     because it is the marker output.
                                   - '0x00' means output 2 has an asset quantity of 0.
                                   - '0xe5 0x8e 0x26' means output 3 has an asset quantity of 624,485.
                                   - Outputs after output 3 (if any) have an asset quantity of 0."

Could you tell me how they calculate quantity of assets by the marker output?
I thought that 0xac is 13(c)*16^0 + 10(a)*16^1 = 173, but it seems the idea is not correct.


texts: How much hashpower is needed to double-spend? Is >50% a minimum?

texts:
How much hashpower is needed to double-spend coins?

Some worry only about one entity getting over 50% of the hashpower, while others are complaining (at the time of writing) about an entity having more than 33%. What is the importance of 50%? Can a double-spend be done with less?


texts: Have 10 of 12 of my mnemonic along with the BTC address, how can i automate recovery?

texts:
So I wrote down my mnemonic on a piece of paper and somehow the last 2 words got ripped off and I cannot find where it went. I do have 10 out of the 12 word phrase still (along with the order, they are 1-10), along with the last address that coins were sent to on it.

My question, is there a way to automate finding the last 2 words? I found various examples online for finding 1 out of 12 but nothing about situations with 2 out of 12 missing. Given that theres only 2048 words in the dictionary for it and each word in the mnemonic can only use certain ones from this dictionary, I'd presume this wouldn't be too difficult of a task. Preferably, Id like to find a way to not only generate the phrases but also check them for a balance in the blockchain if possible. Anyone know how I should go about this given what I have?


texts:
My goal is to understand the bitcoin internals.

Here is what i have done:

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

I have launched the bitcoind daemon. Everything seems to work because i can generate addresses with bitcoin-cli.

My first question is: When and How my private/public key was generated ?
I had nothing to do for that and i am wondering when this operation was done.

My second question is: I know this is not a good practice but if i only know my private/public key in clear format (not encrypted): Is there a way for me to "import" this public/private key into my bitcoin wallet.
In other words, can i say if i know my public/private key, i know everything.

Thanks


texts: Is it possible to get the standard private key from a too long private key?

texts:
We know the private key should not be longer than 256 bits.
But if I choose one longer key X, for example 300 bits key, and use it generate a pub key and address. Can I use X to generate the standard private key Y to signature the address properly?


texts: Why does the wiki say that green addresses are "generally considered a bad idea and not advisable to implement."?


texts: Will a channel be automatically closed if there's a expiring HTLC that doesn't have its own output in the commitment transaction?

texts:
When routed Lightning payments are smaller than some amount they don't get their own HTLC output in the commitment transaction. Instead the funds reserved to it are directed to transaction fees.

When there's an actual HTLC it makes sense for the sender to close the channel and claim it back when it's expired, but it makes no sense to do the same when there's not a real HTLC in there. The same applies to the receiver.

But still, will a channel close in these circumstances?


texts: How to find details about very first block mined for any crypto?

texts:
Hi is there any resource or site where we can see details of the very first block mined like its time-stamp and other details . I have been asking around in groups for last 3 days no answer .

I did find some details about bitcoin but would like to find for other crypto coins too.


texts:
I just found an old backup of a bitcoin wallet on a USB stick containing 4 folders:

key-backup - empty
rolling-backup - contains a .wallet file stamped with a date from 2014
wallet-backup - empty
wallet-unenc-backup contains a .info file and a .wallet file

The info file includes this

multiBit.info,1
walletVersion,2
property,walletDescription,Your%20wallet%20description
property,walletBackupFile, *path to the .wallet file*

Is it possible to recover this wallet? I've tried downloading multibit, but the new version needs a phrase (which i don't have) and one of the older versions needs a .key file


texts:
I have set up a full node on my server. Now, I want to make use of HD wallet methods?

How I generate an address for admin - Master address

How I generate addresses for customers - Child address

When I receive the deposit on child address, how it can be viewed on Master Address?

Do I need to transfer to the master address?

As I want to move all amount to my Cold wallet address so to do so I need to have a balance on my master address?

Please help


texts:
There are currently many cryptocurrencies based on PoS (Proof of Stake). All these PoS algorithms differ from each other. Some or maybe all of them (I don't know) implement some kind of random election of nodes who participate in the "bookkeeping-process"/"block-forging-process" via having some amount of stake.

How can a random election work in an trustless decentralized environment?


texts: Can my transactions be traced back to me even if I do this?

texts:
I installed the wallet from Bitcoin's official website on 4 computers each running Microsoft Windows 7.

Moreover on each of the 4 PCs, I installed OpenVPN client, meaning each of the computers access the internet via VPN.

Suppose I do not use an online Bitcoin mixer to further anonymize my transactions.

Instead I transfer my Bitcoins from one computer to another, all the while making sure that the VPN gateway/exit node is located in a different country.

Question: can my transactions be traced back to me?


texts:
I'm currently working on a system that provides payouts to users from a bitcoin address as they 'burn' other assets on the site (think something like ShapeShift, where you pay someone BTC to get some other cryptocoin, and you pay this coin back to get BTC).

I'm using public apis to build and send raw transactions using bitcoinjs. However, I have the issue that I sometimes need to wait for previous transactions to confirm before I can send more out. This will often involve bitcoins that will - no matter the result of the confirmation - be mine.

Here's an example. I have 10 BTC, and I have posted a tx to User 1, sending him 5 BTC and 5 BTC back to myself. Now I am sure that I have 5 BTC in my account (regardless of whether the tx confirms) - but this isn't easy to confirm for me, especially when multiple such txs get chained and a lot more inputs and outputs get involved. How do I check and design a transaction so that I can send 3 BTC to User 2?

Can I chain unconfirmed transactions? I understand this would be dangerous if any of the transactions failed (insufficient fee, corrupt data, etc). Setting this aside, would there be a possibility that the transactions aren't mined in the order they are broadcasted - or that a latter transaction is discarded because a former one does not exist in the chain yet?

Finally, is there a better way to do this? For an outgoing bitcoin account that only makes payments to users, what would be the best practice? Would it be useful to split the account into multiple sending accounts - how is this done on existing systems like exchanges?

I understand there is a similar question here, but it does not discuss transaction ordering, and my concern is primarily about setting up an outgoing Payment system by which I can send multiple outgoing transactions per block as payouts.


texts: what is the difference between eatch coins wallet address,what is the coin public id/salt?

texts:
i looked at the link: http://brainwallet.org/

witch generate offline wallets for all major coins,
i noticed that the same Passphrase generate different  [Private Key&Address] pairs for eatch coin type, witch means eatch coin has a public shared id (or salt) added to the mix of the hash, am i right?

so how can i get that public coins key? and how can i edit the javascript  to support other scrypt coins?

eatch time i change coin in the menu a function is called,
i got that code of the page:

  PUBLIC_KEY_VERSION = parseInt($(this).attr('data-target'));
  PRIVATE_KEY_VERSION = (PUBLIC_KEY_VERSION+128)&255;
  ADDRESS_URL_PREFIX = $(this).attr('href');
 ....
    var eckey = gen_eckey;
    var compressed = gen_compressed;
    var hash_str = pad($('#hash').val(), 64, '0');
    var hash = Crypto.util.hexToBytes(hash_str);

    var hash160 = eckey.getPubKeyHash();
    var h160 = Crypto.util.bytesToHex(hash160);
    $('#h160').val(h160);

    var addr = new Bitcoin.Address(hash160);
    addr.version = PUBLIC_KEY_VERSION;

    $('#addr').val(addr);

when addr is the wallet address....

and the data-target  for the links are:

bitcoin : 0x00
dogecoin: 0x1E
litecoin: 0x30
namecoin: 0x34
.
.
.

is this is the uniqe identifire of the coin? is if possible?
it's just a single byte...

if not than what is?, and if yes how can i get the identifier of other coins, not listed (any way to extract it from the network/wallet software)?

thanks


texts:
I read ScriptSig content during signature (quadratic hashing) discussing quadratic hash problem.

Quadratic hash problem is the issue that signing (or verifying) transaction time grows with the square of the number of inputs (O(n^2) where n is the number of inputs).

Why is that so? I reason the following:

For each input you construct different template. O(n)
This template must be double-SHA-hashed. - Double-SHA-hash duration is dependent linearly on the size of the template?
Double hashed template (of fixed length) is then signed. - as the leght is fixed this step is of fixed duration

As step 2 is dependent linearly on the size of the template, thus it is linearly dependent on the number of inputs, giving final time dependency relation O(n^2)?

More precisely O(n^2+m) where m is the number of outputs (as this contributes in step 2)?


texts: In what scenarios can the blockchain size decrease for bitcoin?

texts:
I am running a private bitcoin network for which I changed the target time between two blocks to 12 seconds and the difficulty adjustment to 25 blocks interval. I ran the network for about 4 hours with 50 nodes. In one of the node's logs I observed that the blockchain height increased up to a maximum of 181 and then started decreasing, all the way to 38. what could be an explanation for such a strange behaviour.

Please refer to the log below:

2015-11-04 01:58:47 receive version message: /Satoshi:0.11.99/: version 70011, blocks=181, us=0.0.0.0:0, peer=2, peeraddr=127.0.0.1:44117
2015-11-04 01:58:47 UpdateTip: new best=0000005265ca4ce01ad0d06f45cf475bf303de3d64e942c5cf1177e00f346c78  height=180  log2_work=37.083283  tx=30941  date=2015-11-04 01:53:17 progress=1.000000  cache=0.0MiB(1tx)
2015-11-04 01:58:47 UpdateTip: new best=00000052a34cedf3c5ddbeb46d36644654523db855c4cce984d2623e840dd219  height=179  log2_work=37.082953  tx=30940  date=2015-11-04 01:53:10 progress=1.000000  cache=0.0MiB(2tx)
2015-11-04 01:58:47 UpdateTip: new best=00000030fd7652affb883f05fe0c98e7fe3fbc3cfd74808e061ed05ec61c22e6  height=178  log2_work=37.082623  tx=30939  date=2015-11-04 01:52:55 progress=1.000000  cache=0.0MiB(3tx)
2015-11-04 01:58:47 AddToWallet c32bcbd8102c602a5e71ee717232e204435f331dce6fbfb9eb5d552698faa95b
2015-11-04 01:58:47 AddToWallet 1c91517aeadd12bcbcfdf4a1423b671d405543ae9abfbd87078969ce1971663f
2015-11-04 01:58:47 AddToWallet b11f9c2e3b1ab3d3983da63783bb95903d89405243d0716ea88272a9261b7a33


texts: Has anyone ever gained control of the blockchain?

texts:
I've heard discussion that if you have 51% of the network's hash power, you can effectively accept or reject any changes to the blockchain (and therefore create undeserved gain for yourself).

Has anyone ever accomplished this? It's theoretically possible, but has it been done?


texts: Is it possible to identify what online wallet service a Bitcoin address belongs to?

texts: Given a Bitcoin address or a record of a transaction between two Bitcoin addresses and a website like blockr.io to explore it, is it possible to identify what online wallet service a Bitcoin address belongs to? For example, is it possible to say that a transaction was send from a Blockchain.info Bitcoin wallet to a Coinbase Bitcoin wallet?


texts: How frequent are side-chain reorganizations of various lengths?

texts:
I'm wondering if anyone has collected statistics on how often reorganizations of side-chains with length 1 happen in comparison with lengths of 2, 3, or more.

Related: What is the longest chain reorganization that has ever happened?


texts: HD Wallets - Generating P2SH-P2WSH Addresses from a ypub-type mpks in PHP?

texts:
I am writing a webapp in PHP that needs to generate Bitcoin addresses from their mpk.

I have successfully done it for P2SH addresses (starting with a 1, with a xpub mpk) using the BitWasp php library, roughly using the method outlined here.

I wanted to do the same for P2SH-P2WSH addresses (starting with a 3, with a ypub mpk) to make use of SegWit, but I always get the same error, using the same method (using the 49' derivation path instead of 44'):

HD key magic bytes do not match network magic bytes.

I have checked and this library can generate P2SH-P2WSH addresses, but so far, I have only been able to generate them from the raw public key (following Bitwasp's examples).

So I was wondering, could I be pointed towards a method to generate the P2SH-P2WSH addresses from their ypub using PHP only?


texts: How can I use a vanity address as my main address

texts:
I obtained a vanity bitcoin address (1MonkeyQWbMzny7BNTA66W9wv6KaCFFAB7) along with its private key. I would like to be able to use this as my main address.

Sites like BlockChain.info allow you to import the bitcoins with a private key, but is there something where I can enter the address and private key and be able to view how many bitcoins I have, and send them from THAT address (not import them to another one, like BlockChain.info does)?


texts: Why was 'extern' used in the noui.h file?

texts:
When I review the Bitcoin Core source code, I see the noui.h as a header file, but the method noui_connect has been declared with the keyword extern. I think there is no need to do this.

extern void noui_connect();


texts: Is there an asset tracking software that supports Bitcoin? (Better than GnuCash)

texts:
Possible Duplicate:
  Any multi-currency accounting ledger that lets me use BTC?

I'm looking for a way to manage all of my assets. I have various assets in multiple currencies & investment instruments.

I think I would like to try using a software that works with double-entry bookkeeping. I'm trying out GnuCash so far, and it seems to do a decent job:

It can easily track all Fiat currencies and has automatically updated prices.
Can be made to work with Bitcoin using the XXX custom currency code.
Is a tad complicated to begin with, but I think over time it's worth it.

Frankly, the one thing I'm missing is integration of an Mt. Gox price feed and the ugliness of writing XXX instead of BTC.


texts: How to send & receive bitcoin using bitcoinjs-lib?

texts:
First I create HD Wallet using BIP32 using mnemonics.

Now I want to generate new child addresses with private key using xpub & xpriv for every receive.

Then for example, I received BTC in 2 child addresses, i.e. 1 BTC & 2 BTC.

Now, I have to send 3 BTC to someone, then How can I send it as I have 3 BTC but in separate account with utxo.

How can I manage these accounts & transaction, and also how can I show the total balance to the user?

I thing it is insufficient to call the api to get balance for all accounts, as for HD wallet user can have thousands of addresses.

So, I understood this theoretically, but don't know how to implement this using bitcoinjs-lib, BIP32, HD-key.


texts: Do mining pools centralize the Bitcoin network and make it less secure?

texts:
A mining pool with a significant percentage of the hash rate could allow double spend attacks by the pool manager. There are a number of pools that approach this level. However, most people say that a compromised pool would be easily detected, and the attack would be insignificant.

However, isn't this issue not about a single pool but the combined centralizing effect of pools? A moderate-sized attacker could easily compromise more than a few pool managers with a rubber hose attack, or pose as legit pools for a while until they obtain nearly complete control of the block chain.

The attacker would be able to double spend a lot of bitcoins (that it generated for itself with its pools in the first place), and regardless of any monetary advantage it could destabilize and destroy confidence in bitcoin. Easily within the capabilities and motivations of a government. A well-planned attack could happen far quicker than anyone could notice and pull their miners from the pools.


texts: Are market prices listed by exchanges weighted by transaction size?

texts:
Suppose I buy 0.0001 BTC for $1.23 on some hypothetical exchange. Does that mean that the market price on that exchange at that time is $12,300?  The reason I ask is that there is a huge difference between the willingness of buyers to pay inflated prices for miniscule fractional amounts of BTC and the willingness of buyers to pay $10,000 or $15,000 for a "whole" bitcoin.

Do exchanges, as a rule, weight their calculation of market price by the size of the transaction, or do transactions involving fractional units of BTC count the same as large transactions involving whole units of BTC?


texts: What stops an attacker from crippling the Bitcoin network?

texts:
An individual (or government) who wants to bring down the Bitcoin network could conceivably broadcast a ton of junk/illegitimate transactions to the network thereby consuming the bandwidth and processing power necessary for the network to deal with legitimate transactions.
I understand Bitcoin has two protocols in place to address this vector of attack:
1) First and foremost it has each node verify all information received before relaying it to its peers. As such, an attacker would barley get past first base (i.e, legitimate node 1) to be able to cause catastrophic damage to the network at large
2) banscore (which effectively computes how bad a node is behaving. Once it reaches a certain critical threshold a neighboring node will stop receiving connections from that node/IP for a period of time)
My main question is: considering the fact that the government (or a government run entity) controls IP allocation isn't this solution completely reliant/dependent on a centralized entity to work effectively?


texts: Need help to recover blpckchain.info wallet, my wife forgot her password and the brute force with btcrecover is not catching the password

texts:
I used btcrecover to extract the wallet file (wallet.aes.json) from a blockchain account and I have been running btcrecover with dictionaries of my making but it has been going on for weeks and I am running out of ideas on how to permutate what my wife and I think the password could have been.  Is there a way to just manually transfer the btc from the old wallet into a new wallet we do have access to or is there any way to extract the password or private keys directly from the wallet file?

We have: the phone with the original wallet app installed, the wallet file pulled using btcrecover, access to the email to allow authorization to access, the wallet identifier that was sent to her email when she first signed up, the phone which has the wallet, the pin that was used for the wallet, and we know how much btc is in the account.

We do not have: The private keys, a backup file downloaded from the blockchain api, a recovery phrase (it was never set-up), 2fa enabled on the account, access to the wallet file on the phone (as the phone was not previously rooted and the files are hidden somehow).

I had a blockchain wallet on my phone and when I knew I was going to switch phones I had my wife make a wallet on her phone in advance so I could keep our btc in her wallet during my transition.

The day came and I transferred the btc to her phone. It made her feel special to have it on her phone so I let her keep it there for a while....until I needed it to make a purchase with a visa card I have linked to another account and I took her phone and used the pin to unlock it except....it didn't unlock. I was sure I was using the right pin because it was the same one she always uses but thought perhaps I just mistyped something. I tried a total of three times and then it said I was locked.....that was annoying so I brought the phone back to my wife to open it with her password and she said she used a different pin this time to be more safe but that she didn't remember which password she had used to set it up.....

we tried numerous different passwords manually with no success and then we reached out to the blockchain wallet customer support with a back and forth conversation that ultimately led to them saying they can not help and we should just keep trying passwords.

I have worked with a few friends tried have so far been able to successfully use btcrecover on a test wallet to download a wallet file and then use the brute force features on a dictionary file to discover the password (which is easy because I already know that password).

But now that I am trying it on my wife's wallet the dictionaries were taking too long so I rented virtual computers online which are faster than my own pc and then I was returned with "password search exhausted" now I am trying new dictionaries but I am worried that we may not get it.  the more wildcards I put in the dictionary the longer it takes....

Also pywallet does not seem to be able to read the wallet file that comes from the blockchain wallet. I couldn't get it to work on any of my test wallets and so I have never tried that program with my wife's wallet.

Can anyone help!?


texts: Could miners create a cartel to raise transaction fees?

texts:
Could miners with enough mining powers (say >95% of all blocks) form a cartel where they demand absurdly high transaction fees? Of course, I still could could hope for a miner not in that cartel to relay my transaction for a lower fee, but in that case I couldn't be sure when my transaction gets paid to the adressee.

Is this a plausible scenario?


texts: Given the bitcoin difficulty information in https://bitcoinwisdom.com/bitcoin/difficulty, determine the bitcoin difficulty on April 1, 2019 and April 1, 2020. State any assumptions made in this determination.


texts: in the white paper you have 2 sides : attacker and honest node

texts:
What does it mean that there is either the attacker or honest node.
This means that within 10 minutes either attacker or honest node mines a block but what about neither OR another side ? How could this be interpreted ?

Does it make sense or what is interpretation of neither attacker nor honest node succeed in finding a block ? What would that mean for the consensus rule that there is a third side ?


texts:
Whenever a news article is written about bitcoin, it has this "physical" gold/brass coin with detailed circuitry on it as an article picture.

For examples see here and here.

Does this really exists? Who makes them and where can I buy one? Is it from gold? I am specifically interested in the coin with this "detailed circuitry" like the two on the pictures I linked. I was able to find some sellers of physical coins, but they are not as detailed/precise.

What other physical coins "of bitcoin" exist?


texts: Making a read-only Linux SD card, where are the security loopholes? (offline key generation and signing)

texts:
I have already identified a way to make an SD card truly read-only on HackaDay.

So let's consider this situation:

A third party have used dd to transfer the Linux image to an SD card
The PERM_WRITE_PROTECT bit is set and can not be changed
There is a hash of the image that will be checked on booting from the card
The developer have signed the hash with PGP and this is clearly stated online

The purpose of this card is to be able to boot a computer you already own and to know that what was intended to boot is actually running. Could uEFI or BIOS in a computer be compromised?

Security should enable the user to:

Generate a paper wallet
Print the wallet with a USB connected printer
(Other actions needing high security precautions)

To do this with confidence, both the SD card and the code to generate the keys must be verified (hash and PGP signatures) by the user. What am I missing? Are there any loopholes in this combination of hardware and software?


texts: How do I install a second independent C-lightning node on the same machine as one with an already operational node?

texts: I have followed the steps to install a C-lightning node on my Ubuntu machine.  I wanted to know if I could install configure and make a second node on the same machine where both could run in tandem?


texts: How to download blk.dat files from a specific block number?

texts:
I want to download blk.dat of a specific block number, How can I do this ?

Note: I'm only interested in specific blocks, I only want to download blocks for example that are numbered between 100 and 200,etc...


texts: How to add a second user with SSH access to my Ubuntu PC running Bitcoin Core?

texts:
I have a friend who is interested in learning Bitcoin CLI, and I told him I would look into giving him access to my node - in a non-destructive way - perhaps testnet only ?

Totally trust this person, we work together closely on many projects, and he's interested in learning about the network but doesn't have the means to set up a full node himself. I tried lots of searching but couldn't find a clear response.

I want to preserve the integrity of my node, not give him access to my user account, but let him use it for educational purposes.

Any kind souls have a guide on this process?


texts: What is the best way to generate bitcoin wallet?

texts:
I am trying to create a cold storage, and I'm becoming so paranoid about everything on software and hardware (also afraid of myself forgetting/losing the wallet) related to the setup.
I have read some information online about cold storage setup, and I have come up with these questions:

What is the safest way to generate bitcoin wallet? From the existing software such as bitcoin-core? electrum? (I thought of writing my own codes to generate bitcoin wallet, but there are so many types of bitcoin wallet BIP32, BIP39, etc which makes me think that it's not a good idea to do so)
How are we sure that bitcoin-core and electrum is generating a safe wallet? (not pre-seeded)
Which standard is the safest way to generate bitcoin wallet? BIP32, BIP39?
Does bitcoin-core uses BIP32 to generate the wallet? if not, which one does it use?
Does electrum uses BIP39 to generate the wallet? if not, which one does it use? (I read that electrum is using an extended BIP39.
I also read that bitcoin-core is not using BIP39 because it is not sure, but why BIP39 is still used in many wallets?
Is it possible that a hardware (CPU, motherboard, SSD, old computer that has been used by me before) is infected with a malware (from previous use or even from the manufacturer)? This malware might be able to mess with the entropy and create something like a pre-seeded wallet?

Thank You


texts: I am on a pool that asks you to select a difficulty for your miner. How can some shares be harder than others if they are just a hash?


texts:
I wanna setup a dnsseed for a crypto currency using sipa/bitcoin-seeder on my VPS.
The server is hosted at NetCup and running the software as root, and also listening on port :53 UDP.

My domain is hosted at GoDaddy and got those records:

dnsseed.machinenode.de  1800     IN     NS  ns01.machinenode.de.
ns01    1800     IN     A   SERVER_IP

However, if I use dig -t NS dnsseed.machinenode.de I just get NXDOMAIN as status and no namserver returned.

Is anyone familar with setting up a dnsseed and able to help?

Thanks and friendly regards

Nico

EDIT:

After switching my servers OS from CentOS 7 to Ubuntu 16.04 things started working.


texts: cannot decode block 0 to find the output address. I can decode much higher blocks. what am i missing?

texts: Can you please decode block 0 output transaction manually showing me how to get the output address namely: 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa


texts:
List of nodes blockchain.info is connected to...

Total Connected: 0

Link on blockchain.info

This service is temporarily unavailable?


texts: Where is Australia's second bitcoin ATM machine?

texts:
Last ABC1's 7:30 ran a balanced Bitcoin story.

http://www.abc.net.au/7.30/content/2013/s3926368.htm

In it they showed a Bitcoin ATM being use in Melbourne.

They also said "One way to buy Bitcoins is using Melbourne's first Bitcoin machine. It's one of just two nationwide".

I haven't been able to google up where the second machine is. Possible places mentioned online are Melbourne (different provider), Sydney and Nimbin.

Anyone know were this second AMT machine is?


texts: How to obtain your nodeID (QR code) in eclair-mobile?

texts: I want someone to open a direct (no hops between us) channel to me in lightning (she will be the funder, I'll be the fundee). How can I get the QR code of my node in my eclair wallet to show to the funder? I don't find the UI/setting for it.


texts:
what is bitcoin-cli command for checking how many transaction per block ?
Thanks you


texts: can I create addresses based on what I want to look like?

texts: Hi I am completely new to bitcoin. I was wondering if it is possible to create addresses based on how the final outcome you would like to be. For example, I dont like something like that 1L5gu6zJHxtAiDM74heP7wW84PYQ5Ltc9o as it is extremely difficult to remember. Could it be possible to create something like that eg., 1L5a5a5a5a5a...c9o i.e. decide the final letters or an approximation?


texts: State of privacy-preserving light clients

texts:
Currently, it is trivial to operate a SPV wallet in Bitcoin at the cost of a lot of privacy due to the necessity to connect to full nodes that offer SPV services.

Neutrino, currently being worked on by the lightninglabs team is one of the few privacy-preserving light clients in Bitcoin. But how does it work?

What theoretical solutions exist that can solve SPV privacy problems?


texts: What is a Stratum "mining.set_difficulty" command for?

texts:
On the Stratum protocol the server may issue the following notification:

{ "id": null, "method": "mining.set_difficulty", "params": [2]}

What is this difficulty used for? from my understanding the the difficulty is sent with the mining job as an encoded difficulty.

Source:
https://slushpool.com/help/manual/stratum-protocol


texts: How much inflation does Bitcoin have, year by year?

texts:
What's the M0/MB inflation rate of Bitcoin?

Note: I'm asking about multiple years in order to make this question less likely to go out of date.


texts:
After connecting to a busy lighnting node such as 03c856d2dbec7454c48f311031f06bb99e3ca1ab15a9b9b35de14e139aa663b463@testnet-lnd.htlc.me the number of channels my own lightning node knows about becomes very large.

Is there a way to get the lightning-cli listchannels command to apply a filter and list only the channels my node is directly participating in?


texts:
I am attempting to sync from scratch a full node (v0.15.1) on a linux machine (Linux Mint running Ubuntu precise 12.04.1 LTS).
The sync grinds to a halt on block #338818.
From examining debug.log I can see the issue is the next block #338819 being deemed invalid. Here is an excerpt from debug.log demonstrating that:

2018-02-02 16:36:52 ERROR: AcceptBlockHeader: block 0000000000000000159e7d66c954312bccb5f12de808f2991b3859205665c442 is marked invalid
2018-02-02 16:36:52 ERROR: invalid header received
2018-02-02 16:36:52 ProcessMessages(headers, 162003 bytes) FAILED peer=217

bitcoin-qt continues to ask peers for the block header and keeps rejecting it as invalid, even though this block seems to be valid as part of the main chain, at least according to all known nodes that I checked (e.g. blockchain.info, blocktrail and several others).

I googled for this block # and found nothing, so I assume nobody else has this problem. What is going on? What should I do to continue with the sync?


texts: Correlation between business cycle and BTC price

texts:
I would like to know if there is a correlation between business cycle and Bitcoin price, whether it is negative or positive.

I am wondering because Bitcoin is deemed as commodity in my country's law, and commodity prices tend to have strong correlations with business cycles. (i.e. gold, oil, ...)

Any suggestions or evidence?


texts: Compiled version of bitcoind 0.18.1. "Could not connect to the server 127.0.0.1:8332"

texts:
When I use the official installed bitcoind 0.18.1 everything works fine. I can use the bitcoin-cli with any comands and don't get any errors.
After that when I compiled 0.18.1 myself I can't use any bitcoin-cli comands and I get:

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

I use bitcoin-cli without any options, just a: bitcoin-cli.exe getbalance or bitcoin-cli.exe stop

Here is my simple bitcoin.conf which I use with the both versions:

server=1
rpcuser=username
rpcpassword=password
rpcallowip=127.0.0.1
rpcport=8332
datadir=F:\BitcoinData

I compile it with MinGW-w64-i686-posix-sjlj on Win7 target platform and with boost 1.57, libdb 4.8.30, openssl 1.0.1, libevent 2.0.22 as a dependent libs. I tried to compile 0.16.1 verion with the same stack but error is a similar:

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

What is wrong with compiled version? I can't realise what I missed. The compilation went without any errors. May be I missed some ./configure options?


texts: Can Bitcoin be recovered from a child key alone?

texts:
I have a question regarding BIP-32 and keys.
Imagine a scenario in which a user creates a new Bitcoin wallet with a seed phrase. He then generates a new address and sends 1 BTC to this address.
Under the covers, my understanding is that a master private/public key will be created from the seed phrase. Then, a child key is created under the parent key for the address.
Now, suppose this user completely loses their seed phrase / master keys, BUT they somehow have a copy of the child key pair that contains their Bitcoin.
Is it possible to recover their Bitcoin from that child key alone? If so, what is the process? Are individual child keys just the same as normal (non BIP-32) key/pairs?
Thanks!


texts: My blockchain.info wallet was hacked. How can I create a double send to foil the attacker?

texts:
This is the transaction.

https://blockchain.info/address/1F8EP97jgQx8QD6XMRg2bCHHrJrZEMUTRt

Which is still unconfirmed.

I am trying to use https://coinb.in to create a double spend transaction with a higher fee but I am getting several errors such as:

18: txn-mempool-conflict OR
16: mandatory-script-verify-flag-failed (Script failed an OP_EQUALVERIFY operation)

How can I create a double spend transaction using https://coinb.in to block this attack?

In particular what goes in the transaction id field and the script field.


texts:
I'm looking for a program or something to run from the terminal in mac.
That does the same thing as the program found here. http://www.blockchain-basics.com/HashPuzzle.html?nonce=221

What I'm looking for is the ability to check how many times a hash using the same hash- Noucing up has two leading zeros. I want to be able to list each hash for 20 hashing of two leading zeros.

Eg. "HI 183" hashed has two leading zeros
Eg. "HI 2121" hashed has two leading zeros.


texts:
Since the output can be spend only once, I am confused by transactions containing multiple recipients. For example, if Alice transfers 5 BTC to Bob and 5 BTC to David in the same transactions. In the future, Bob refers to the Alice's transaction, also David can refer to the same transaction. I understand that outputs are numbered in Alice's transaction to Bob and Eve. Therefore the output number and transaction id Tx id uniquely determines whether there is double spend happening or not.

Am I correct? Is the UTXO associated with output and Tx id?


texts: How much will be the fee after all bitcoins are mined?

texts:
Because mining is every time harder, and hence more expensive, right now is profitable because the btc is rising, but what will happen when btc price is stable and miners won't get any extra reward, only the fee.
If the fee is high then we will end in a worst scenario than current transactions with banks :(
Is there any approximation about this fee? (In btc because we won't know the price in usd)

EDIT
similar question (but too old, without answer):
How much will transaction fees eventually be?
Maybe this could be a good approximation
How many BTC are transferred per day (daily volume)?: 750.000 BTC (source: https://coinmarketcap.com/currencies/bitcoin)
How many BTC are mined (generated as reward) every day?:
1800 BTC (source: https://www.bitcoinblockhalf.com/)
How much is paid in fee every day?: 34 BTC (source: https://blockchain.info/stats)

So right now the fee is 34 / 750.000 = 0.0045%
But if we mined everything, then we need to pay the 1800BTC to miners in fees to compensate so will be (1800+34) / 750.000 = 0.25%
If this is the case I think is cheaper than current bank transactions fees...

But I'm not sure if this is a valid approximation, fee seems to change a lot (not sure why or even how to read this graph either): https://bitcoinfees.info/


texts: What is the meaning of "Position in mempool" for a transaction?

texts:
I am using Electrum as my wallet and when I am receiving a transaction, I see an attribute with the name "Position in mempool" and the value is "8.61 MB from tip". Since the transaction is still unconfirmed, I understand that this value gives information of how close this transaction is to being included in a block but I am not sure how to read it and did not find answers in the documentation or other sources.
Does anyone know how to understand/read that value?


texts:
I am trying to figure out when the ASIC mining era began. A Bitcoin magazine article from January 23rd 2013 announces the imminent arrival of the first batch of Avalon miners in early February.

Is there more accurate information: What day did the first ASIC miner become operative?


texts: Difference between coinbaseaux.flags vs. coinbasetxn.data?

texts:
After reading through most of the protocol, and trying to piece everything together, I'm still at a loss as to how some things work. For example, the difference between coinbaseaux.flags and coinbasetxn.data.

With coinbasetxn.data it makes sense, because it's already built, and we can use that data to modify the coinbase data if needed and then add to transactions for merkle root. The coinbaseaux.flags data on the other hand doesn't make much sense to me. I couldn't find any mention of the flags option.

Below are 2 transactions - one using coinbaseaux and the other coinbasetxn. If anyone could explain how coinbaseaux can be used to build the coinbase transaction, or if it's for something else, that'd be greatly appreciated!

{
    "result":{
        "version":2,
        "previousblockhash":"00000000000000075f2f454573766ffae69fe41d6c7ccfcabbf8588fcd80ed52",
        "transactions":[
                  {
                        "data":"0100000001cba672d0bfdbcc441d171ef0723a191bf050932c6f8adc8a05b0cac2d1eb022f010000006c493046022100a23472410d8fd7eabf5c739bdbee5b6151ff31e10d5cb2b52abeebd5e9c06977022100c2cdde5c632eaaa1029dff2640158aaf9aab73fa021ed4a48b52b33ba416351801210212ee0e9c79a72d88db7af3fed18ae2b7ca48eaed995d9293ae0f94967a70cdf6ffffffff02905f0100000000001976a91482db4e03886ee1225fefaac3ee4f6738eb50df9188ac00f8a093000000001976a914c94f5142dd7e35f5645735788d0fe1343baf146288ac00000000",
                        "hash":"7c90a5087ac4d5b9361d47655812c89b4ad0dee6ecd5e08814d00ce7385aa317",
                        "depends":[],
                        "fee":10000,
                        "sigops":2
                  },
                  ...
            ],
        "coinbaseaux":{
            "flags":"062f503253482f"
        },
        "coinbasevalue":2501100000,
        "target":"0000000000000026222200000000000000000000000000000000000000000000",
        "mintime":1379549850,
        "mutable":[
            "time",
            "transactions",
            "prevblock"
        ],
        "noncerange":"00000000ffffffff",
        "sigoplimit":20000,
        "sizelimit":1000000,
        "curtime":1379553872,
        "bits":"19262222",
        "height":258736
    },
    "error":null,
    "id":"curltest"
}

VS.

{
 "error": null,
 "result": {
   "coinbasetxn": {
     "data": "0100000001000000000000000000000000000000000000000000000000000000
0000000000ffffffff1302955d0f00456c6967697573005047dc66085fffffffff02fff1052a01
0000001976a9144ebeb1cd26d6227635828d60d3e0ed7d0da248fb88ac01000000000000001976
a9147c866aee1fa2f3b3d5effad576df3dbf1f07475588ac00000000"
   },
   "previousblockhash": "000000004d424dec1c660a68456b8271d09628a80cc62583e5904f5894a2483c",
   "transactions": [],
   "expires": 120,
   "target": "00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
   "longpollid": "some gibberish",
   "height": 23957,
   "version": 2,
   "curtime": 1346886758,
   "mutable": ["coinbase/append"],
   "bits": "ffff001d"
 },
 "id": 0
}


texts: How does Bitcoin avoid splitting into multiple p2p networks?

texts:
So since Bitcoin is completely decentralized what stops multiple p2p networks from being formed?

And what happens with the block chain when two separate P2P networks eventually reach each other? Will all the nodes just agree to use the longest block chain?

Wouldn't that mean that a bunch of transactions would be lost?


texts:
What happens when I put a deposit into my wallet, while my computer is offline?

Lets say for example, I automatically deposit btc from a pool to the wallet on my computer, but I shut my computer down for a week/month/ or whatever.
Will the Bitcoins be in some kind of "cloud" until my computer/wallet is online again?
How does this work?

Thanks!

-Kevin


texts: Is this brainwallet approach safe enough?

texts:
Let's suppose I derive a private-public keypair from a passphrase like this :

long_and_complex_enough_but_yet_easy_to_remember_passphrase

Now I wish to generate 100 more keypairs using same passphrase, so I append consecutive numbers :

long_and_complex_enough_but_yet_easy_to_remember_passphrase_001
long_and_complex_enough_but_yet_easy_to_remember_passphrase_002
long_and_complex_enough_but_yet_easy_to_remember_passphrase_003
...
long_and_complex_enough_but_yet_easy_to_remember_passphrase_100

Is this safe enough to do, as long as the initial passphrase is enough complex one, or maybe the consecutive numbers add any vulnerability ?


texts: How can I get the transaction history of a bitcoin address?

texts: Lets say that I have a bitcoin address that is not owned by me. Is it possible to get that address's full transaction history (send/receive addresses and amount), and if the owner bought bit coins using a credit card will I be able to see that and possibly the card number? If not, what can I see with just a random bitcoin address, and who can see that credit card number?


texts: Relation between bitadress and blockchain

texts: When i create a wallet at bitaddress.org i could see my balance at  https://www.blockchain.com/explorer . If bitadress.org is a client sided page and shouldn't send any information to outside world and I haven’t shared the wallet address with anybody, how does the blockchain.com/explorer page know if an address is included in a wallet?


texts: When will the official client support partial blockchain downloads?

texts:
Are there concrete plans for the official client to be able to download just a portion of the blockchain?

By concrete I mean what's the issue tracking this on github, is there a planned version for it?


texts: Can I buy Litecoin with Paypal or a credit card?

texts: I've been looking into Litecoin Lately and couldn't find any easy option to buy it using a credit card or my Paypal account. Am I missing something or is it just not possible ?


texts: Connect a mobile client to wallet on remote Bitcoin Core

texts: I run a Bitcoin Core node on my computer and have a Windows tablet. My wallet is on the computer and I want to keep it there. Is there a way to have my tablet create a new Bitcoin address for my wallet by telling my node to do it and sending me the result, thus keeping my private keys and wallet off my tablet?


texts: How to view a specific unconfirmed transaction with an online service?

texts:
Is there a web service out there that could show mempool transactions based on a specific filter (eg. arbitrary destination address)?

Note: I expect a bitcoin client such as Electrum can do that

Especially those days when bitcoin transactions are especialy difficult, this kind of tools must exist


texts: How can low latency and high scalability be achieved with increased block size in BTC?

texts:
One of the solution to address low latency and high scalability in BTC is to increase block size.
A single block takes 10 min on average for proof-of-work. Increased block will also take same time for proof of work and network latency will be increased.
A transaction when recorded in Blockchain will become valid only after proof of work is validated through consensus. I fail to understand how will increased block size decrease time for transaction to become valid and recorded in ledger. At max, It will just allow more number of transactions in any given block.


texts: What happens with a valid block which contains a transaction which was already included in previous blocks? Is such a block accepted by other nodes in the network or discarded?


texts: Can a bitcoin transaction hold an arbitrary string or strings for reference?

texts:
I'm not too sure how I can expand on this.

Let's say that you want to tag the actual transaction with 'Rent' or 'Bill'.

Is there a field where I can insert a string for the other party? Note that this doesn't need to be hashed, it can be clear text.


texts: How to specify number of threads for bitcoind?

texts:
What field in config file or flag should I use to run bitcoind -daemon e.g. on 100 threads? Now I have 23 threads, but I want to increase this value.

$ ps aux | grep bitcoind
pavlovd+  1258  2.3  1.7 2682460 916020 ?      Ssl  Aug05  43:22 bitcoind -daemon
$ ps -o nlwp 1258
NLWP
  23


texts: Is there actual economic value in trading crypto currency?

texts:
When you invest in a stock, you're helping the company to raise capital.

It seems like trading crypto currency is nothing more than putting money into a pool (market cap) and trying to predict when other people will put more money into the pool. No economic productivity happens here except for money changing hands. Is there actual any value in trading coins or is it just money changing hands?


texts:
Is it possible to send 100% of the funds from one account to the exact same account?

Essentially, such an operation would be a NOP, but could be used as "proof of ownership" (e.g. by adding a comment with the transaction in reply to a proof-of-ownership challenge).


texts:
I've just installed the electrum wallet accordingly said by every other website but wasn't able to find my wallet address under the receiving tab or anywhere as mentioned over the internet.

Also what are these multiple addresses stated under addresses tab; difference between receiving and change address? Why have so many receiving addresses, have to manage the private key for each.


texts: How do faucets/micropayment-based services avoid/minimize transaction fees?

texts:
Sites like bitvisitor or cointube give away very small amounts of bitcoins (I actually got a payment as small as .0000035 BTC when testing).
I am in the process of creating a service that awards users small amounts of bitcoins in exchange for doing some trivial work (akin to Amazon's Mechanical Turk). When experimenting, I tried using bitcoin-qt to send .0001 BTC to an address and it automatically added a .0005 fee onto it. Using Electrum, I couldn't get it to send until I set the fee to .0001 as well.

I highly doubt a fee like that was paid for the .0000035 BTC I received earlier), so how are these services eliminating or minimizing their fees? I know it's common to gather multiple "inputs" into a single transaction. Is it possible also to have a transaction with multiple outputs so that I can gather a hundred of these .0001 BTC payments into a single transaction and thus minimize the size (in kb) of the transactions and therefore the fees too?

EDIT
Sites like BitVisitor do indeed combine these payments (see here). So assuming there's no better way to minimize fees, how are they able to do this? I see no options in bitcoin-qt or Electrium for this.


texts: Is there a command I can type into Bitcoin-Qt to see the total number of bitcoins that have been created?

texts:
I know how to obtain this information from other means, I specifically want to know if it's possible for me to obtain this information using the Bitcoin-Qt client alone.

I am running it on Windows Vista and I don't have a miner set up.

Thanks.


texts: Solo mining: gen=1 needed when using minerd?

texts:
I'm guessing maxcoind follows the same conventions as bitcoind. I've read up most everything except the actual source code but it seems that's the only place to find my answer!

Anyways, so when I go ./maxcoind getmininginfo - I get hasheshpersec = a fraction of what's pumped into it by ./minerd.

When I go ./maxcoind setgenerate false, hasheshpersec drops to 0... while minerd still happily spits out a huge KH/s rating per thread.

My question is thus: Does the wallet daemon (maxcoind/bitcoind) need generation to be set to on in order to mine solo with minerd?

And why doesn't those hashes show up in hashespersec?

As I understand gen=1 makes bitcoind/maxcoind mine... and that makes sense, seeing as that the hashrate reported is basically equivalent to the hashrate per thread I get from minerd. So if that is so, where do I see the total hashrate fed in by minerd?

And also, can I push multiple minerd instances on many PC's into the same wallet daemon?

Thanks so much for explaining all this!


texts: When I specify wallet in bitcoin.conf for testnet3, it gets ignored

texts: I have a question about specifying wallet for testnet3. My bitcoin.conf file is located in the root of the Bitcoin folder with the line 'wallet = receiving.dat as well as testnet=1. Whenever I run 'getwalletinfo' tho it still shows no name for the walletname and if I delete the default wallet.dat, it autoregenerates. This is on version 0.18.0.


texts: Is there a way to point bitcoin-qt from inside linux to the blockchain i downloaded in windows?

texts: I duel boot and would like to point linux to the blockchain i downloaded in windows rather than download it again.


texts: Is the idea of color coins/open assets still alive? Are there any interesting projects ahead on this way?

texts: Since Ethereum has taken the way for smart contracts, it seems to me that the color coins projects have been abandoned in favour of the Ethereum ecosystem. But I might be wrong. Are there any interesting projects still for this approach?


texts: Why, when sending BTC to my pruned node's generated wallet, the BTC aren't showing there?

texts:
:) I'm starting development on a PHP project that involves creating a Bitcoin server, creating and managing wallets, etc.

I've created a selfish-node (550 MiB of the blockchain) on Ubuntu 14 with bitcoind and bitcoin-cli and it is live according to https://bitnodes.21.co/ => response: (162.243.145.144:8333 /Satoshi:0.14.2/)

My bitcoin.conf is as follows

prune=550
maxconnections=10
maxuploadtarget=10
rpcuser=fakeusername
rpcpassword=fakepassword
daemon=1
keypool=10000

and bitcoin-cli getinfo outputs

root@b:~/.bitcoin# bitcoin-cli getinfo
{
  "version": 140200,
  "protocolversion": 70015,
  "walletversion": 130000,
  "balance": 0.00000000,
  "blocks": 367670,
  "timeoffset": -1,
  "connections": 8,
  "proxy": "",
  "difficulty": 52278304845.59168,
  "testnet": false,
  "keypoololdest": 1505160918,
  "keypoolsize": 10000,
  "paytxfee": 0.00000000,
  "relayfee": 0.00001000,
  "errors": ""
}

I've created a wallet via bitcoin-cli on this node: 17Jn1VYpwknwjuVxLMYvqc8iHJ6QsP8xDo and have sent this address 0.00000547 bitcoin as a test from an Electrum wallet of mine.

The tx: ee65b8201e0e26827430b34872f6dd961f318e0c1e4c5266a6bcf8a8fa22a2ce

According to the blockchain, it has over 10 confirmations at this point (it is confirmed).

But when I execute commands to verify this from within my server, it does not show any such transaction and it does not show that I have received any funds.

root@b:~/.bitcoin# bitcoin-cli getreceivedbyaddress 17Jn1VYpwknwjuVxLMYvqc8iHJ6QsP8xDo

Outputs

0.00000000

and

root@b:~/.bitcoin# bitcoin-cli gettransaction ee65b8201e0e26827430b34872f6dd961f318e0c1e4c5266a6bcf8a8fa22a2ce

Outputs

error code: -5
error message:
Invalid or non-wallet transaction id

Is this because I am not running a full node? Can anyone shed some light on this?


texts: What does "peer sent transaction already received" mean?

texts:
This is  my output from p2pool.

2013-07-10 16:06:29.543000 P2Pool: 17383 shares in chain (17388 verified/17388 total) Peers: 11 (5 incoming)
2013-07-10 16:06:29.544000  Local: 0H/s in last 0.0 seconds Local dead on arrival: ??? Expected time to share: ???
2013-07-10 16:06:29.544000  Shares: 0 (0 orphan, 0 dead) Stale rate: ??? Efficiency: ??? Current payout: 0.0000 BTC
2013-07-10 16:06:29.544000  Pool: 1074GH/s Stale rate: 17.1% Expected time to block: 23.7 hours

Problem - Why are there '???'s replacing all the values?

Question 1 - What does the 'Peers: 11 (5 incoming)' mean

Question 2 - What does the following line mean? It shows up a lot with different strings of numbers and letters:

2013-07-10 16:10:01.362000 Peer sent entire transaction 59900f72264267f0fbff2041ea50d9b72ba44448aa2244429e855f5372ba2bca that was already received

Thank you for your time.


texts: What software should I use to open the .dat flles

texts:
I've just downloaded the Bitcoin Core for Windows.

I can see several .dat file. What can I use to open them. i.e. Is there a way to view them in plaintext?

Also, which file is the blockchain file?

Thanks!


texts: How to choose between so many open-source bitcoin pool software

texts:
I am now in the venture of finding and setting up a bitcoin pool company. However, after some research, I found out that there are plenty of bitcoin pool software. There are:

CoiniumServ

Cryptonote Universal Pool

MPOS

NOMP

Bitcoin Pool
etc.

I am actually quite confused about the differences of all these mining pool software. Can any kind soul help to explain the differences?
Thanks in advance!


texts:
Where is stored a full data set of bitcoin blockchain?

Is ../blocks/ dir contains a full data for blockchain work?

I know that ../chainstate/ and other files truly contains service information, include hashes, UTXO data set and others. But is it true that the full information already is in ../blocks/ dir?


texts: I want to create a fork/ new chain of Bitcoin which I can mine and have a wallet to send to another address to learn more about how Bitcoin works. Is there a very easy way to do this? Like can I just fork the github repo and change some lines and compile it all? Or is it a more intensive process? Thanks for the help. A lot of the tutorials no longer work because they are very old.


texts: Hash that defines previous block in Blockchain vs mathematical solution

texts:
Is the hash that defines the previous block (block A) in a new block (block B), the same as the hash the miner calculated to submit block A?

As far as I know, you need to find a nonce so that the hash of the entire block A starts with zeroes. If you find a fitting nonce is this hash with the zeroes used by the next miner in his block b when he links to your block with the previous hash?

To clarify, if person A found a nonce so that the hash of his block is 000231 is the hash in the previous field of the next block also 000231?

Thanks


texts:
I always struggle here and tried both ways plenty of time

i use the rubygem "moneytree" and electrum 3.3

@master = MoneyTree::Master.new
@master.to_bip32(:private)

this will give me tprv8ZgxMBicQKsPe8hnfLVQdtZk2qMKnnDQs2ZKLgoJQBhedKQ5vB7srAb6Tk2iUYNkhaacTjNP9WzkbjCqPjk8ExUFGECbiR1Z8tZDs76jytn

however, i can't import this in electrum. the next button is just non active.

i tried the other way around and created a wallet with seed fabric body bright coffee special music virus raccoon side double shield shrug and exported the master public key which will gives me xpub661MyMwAqRbcGq54zC5FfD3rTjgcAGd36JvtW6r4RGheQjSdUVqAS9Q1DLAvzyvvxdYziZced4Y6kHLCqo73vuB4gGSpt6tJwtCWYm8zsBb

now i'll run the following

master_pub_key = "xpub661MyMwAqRbcGq54zC5FfD3rTjgcAGd36JvtW6r4RGheQjSdUVqAS9Q1DLAvzyvvxdYziZced4Y6kHLCqo73vuB4gGSpt6tJwtCWYm8zsBb"
$bitcoin_root_node = MoneyTree::Node.from_bip32(master_pub_key)

i = 0
20.times do
  p $bitcoin_root_node.node_for_path("m/0/#{i}").to_address
  i+= 1
end

all generated addresses will look like this

mpQPcBLyTqPPCw9dhdXYm3Dvnnn58Y4dwA
mt6UdprJNAuJUtG3BYWTy3dZrST7nZTwtZ

starting with a small M

however, in electrum all the addresses are starting with 1xxxxx

what am i doing wrong?


texts: Buying bitcoins with a credit card without the charges being applied as a cash advance

texts: How or where can I buy bitcoins with a credit card without it being applied to the card as a cash advance? I read the company selling the bitcoins (Coinmama, Coinbase, etc) lists what type of transaction is being made and that's how the type of transaction is determined (i.e. regular purchase or cash advance). Is that true and if so could the bitcoin company control what the transaction appears as? In other words is it possible at one website (for example Coinmama) the purchase would appear as a cash advance and at another website it would appear as a regular purchase?


texts: What parallel, distributed computational techniques can be used for Bitcoin mining?

texts: As far as I have read, I haven’t found a parallel algorithm to speed up Bitcoin mining. Are there any techniques that involve parallel or distributed algorithms, architectures that speed up Bitcoin mining ?


texts: What is more effective than ASIC mining?

texts:
Considering that mining progressed from CPU, to GPU, to FPGA, and now ASIC mining... have we finally hit the end of the road for technological advancement?

What future optimizations can occur after ASICs are widespread?


texts: How does one document Bitcoin investments for tax and other legal issues?

texts:
If Bitcoins are used as a store of value or investment vehicle, what legal documents should the investor require/keep? To date, no jurisdiction has special laws concerning cryptocurrencies, but investors may want to implemented best-practices to avoid later hassle.

Personally, I'd expect a receipt for any fiat-BTC transaction indicating

full name and address of the other party or exchange,
amount in BTC and fiat currency, and
any fees and taxes incurred.

Is this reasonable? Do larger exchanges, Mt.Gox or Bitcoin-central, issue a printable document with this information?


texts: Bitcoin core -trying to open my watch adress with private key- unsolvable

texts:
First of all, please bare with my ignorance. When i bought btc 5 years ago i did not know more than i know today, which is very very little.
However, after retrieving my private key for an crashed hdd, i then created a new wallet in bitcoin core, i downloaded the whole blockchain, wrote -impprivkey in console followed by the private key connected to my old adress, where me btc had been resting for 5 years.
However, after a long scan it shows up in my wallet as unspendable. It shows only as a watch-wallet. Ok, i then write listunspent in console.
I get that the coins are
Spendable - false
Solvable - false
Safe- true
Now what can i do? What may have happened? I do have the private key. I have tried to sweep the coins into an electrum wallet, but since they are unspendable - aint gonna happen.
Any suggestions, anyone?
Thx and have a great day!
Edit:   I am looking at this as a lost case. But however it would be interesting to know what went wrong. Because when i did impprivkey in bitcoin core and waited the numerous hours for the rescan, the bitcoin did show up, but in the form of a watch adress and unspendable. The fact that -listunspent gave me : solvable - false,
Im curious to understand in what was it is unsolvable and why.
Thx again for any answers


texts: Want to write my own solo cpu bitcoin miner

texts:
I just want to understand how this mining process works (from the developers point of view from very start to end). Can someone guide me towards a doc or a open source code (I am newbie here so a VERY BASIC one)?
Thanks in advance


texts:
MtGox Streaming API is down or is something wrong with the code.

I used this example https:// bitbucket.org/nitrous/mtgox-api/src/004c254993963baeb239ac7ac7f676b5024fc93f/socket/ws.client.html?at=master

You can see the example here http://atc.leadsoft.eu/test.html

I entered the server url (https://socketio.mtgox.com/mtgox) and click connect, but most of the time it writes only Connected or Connection timeout and freezes.


texts: How Bitcoin mining contributes to confirmations?

texts:
Based on my knowledge I know (maybe wrong) when a miner is doing hash, he is inputting any arbitrary values, in order to get a value that can be hashed into something with certain preceding zeros. When he got that value, he put that value into the blockchain and generate a new block.

Then how is this contributing, or say, relating to the confirmations? Since the miners are just guessing arbitrary values to get the 0000000 preceded hash.

I think I must have some misunderstanding. I want to know how the hash-guessing is related to confirming the transactions.


texts: Setting up node, no connection when announce ip address to peers

texts: I want to announce my host name when running node. When I set nxt.myAddress=hostname or IPaddress, there are no connection to peers. But when I keep it empty everything is fine.


texts: base58 cannot get 34 chars results (as Bitcoin address does) but 68 chars

texts:
I am trying to convert public key hex to Bitcoin address.

From this website http://gobittest.appspot.com/Address, I can do some test.

For example, I have this public key:

04b4d653fcbb4b96000c99343f23b08a44fa306031e0587f9e657ab4a2541129368d7d9bb05cd8afbdf7705a6540d98028236965553f91bf1c5b4f70073f55b55d

According to the website, the address should be:

1DU8Hi1sbHTpEP9vViBEkEw6noeUrgKkJH

which is the base58 encode of 0088C2D2FA846282C870A76CADECBE45C4ACD72BB655DA1216.

However, if I do Base58 encoding directly on 0088C2D2FA846282C870A76CADECBE45C4ACD72BB655DA1216 on this website https://www.browserling.com/tools/base58-encode, I will get:

bSLwwticQjhNvEtqTMZXbn3dLmFrPvNrDGE4hmHsfADpHWb3b2ruh3XqtNzv8ESS8V6V

which is totally different from the 34-char Bitcoin address.

Anyone knows why?


texts:
Is there a way to display on a website of mine, a new address for every transaction?

e.g., I have a wallet, and every time it receives a donation, displays a new address on my website that corresponds to the address my wallet will recognize, so that no address ever receives two transactions?

thanks!!


texts: I want to create new own wallet without using ready wallet. But there are random generator that create random number and then private key builds from it. How I can realize that there is no two equal private key in the world?


texts: How would SPV proofs be verified when moving assets back in 2-way pegged sidechains?

texts:
I've seen similar questions posted all around, but haven't found an answer I can comprehend.

Ok, so the process of 2 way pegging is:

I move some coins to OP_SPVPROOFVERIFY on the parent blockchain.
I wait for some time (e.g. 1 day)
I get coins on the sidechain, transact.
Now, I want to move some of those coins back to the parent/main blockchain.
I send them to a special address on the sidechains, and they are now locked on that chain.
... magic magic
Now I can "SPV prove" that the coins are done with on the sidechain and are now free for transacting on the main chain.

How does step 6 work?

Assumptions

Only a subset of the parent chain miners & spv & full nodes are aware this sidechain even exists
The sidechain may use completely different proof of work, block format, address scheme (Or rather: what can a sidechain change compared to Bitcoin, and what is fixed?)

Under these assumptions, how can a full node running the parent chain recognize that the coins really vanished from the sidechain (of which they are not explicitly aware)? Remember, the parent full node isn't aware of the type of proof of work (if any) that happens on the sidechain, address scheme, really it only knows and speaks the language of Bitcoin, not the sidechain. So how does step 6 work?


texts: Problem of colored-coins/assets and other coins with a parent/child relationship of paying for fees with only the parent currency

texts:
I've looked into building out my own coin, but it was best to just piggy back on top of an existing blockchain like how colored coins and counterparty is doing it. But when going on this route, I run into the problem of having to pay the fees of using the blockchain in the native currency.

Say if I was to create a game token based off of the bitcoin blockchain on top of counterparty, I still have to pay the fees in Bitcoin. Which my users will not have even if I distributed my game tokens to them. Now they will be stuck with the game token without being able to send it anywhere.

One solution was to monitor these addresses, and just fund them a small amount of btc just for them to pay for the fees. Is there a service out there that does this?

This issue is also apparent in other coins like ethereum and nxt. They give the ability to create your own child coins within their blockchain but you are stuck with the coin unless the holder has the native currency.

How are others solving this problem?


texts: bitcoind systemd service: forking or simple?

texts:
When creating a systemd service file for bitcoind (for example https://github.com/bitcoin/bitcoin/blob/master/contrib/init/bitcoind.service), does it matter if Type=forking or Type=simple? What is the implication of one or the other in the light of how bitcoind starts and runs?

All other coins based on bitcoin share the same behaviour on this matter, or is this something that is likely to be modified by coin devs?


texts: Is there a (potential) "Blockchain size problem", and what solutions are available?

texts:
As more and more Bitcoin transactions are produced, the growth of the Blockchain may well, one day, become a problem for systems which want (need?) to store the whole blockchain.

Storage usage
Client startup time
First-time synchronisation

This answer to "Are there any studies into the size of the blockchain scaling over time?" suggests that Simplified Payment Verification is a good solution, but SPV, as far as I understand it, requires a degree of trust in individual peers that may not be to everyone's taste.

Although I don't really understand the blockchain well enough even to know if this is sensible, the sort of thing that occurs to me might be a mixture of SPV with partial blockchain caching (least frequently used?), where the client keeps a small piece of the blockchain.

Is this really a problem, and is there any work in progress to solve it?

Alternatively, if this isn't a problem, please help me to understand why.


texts: Once SegWit is implemented, could updated miners still choose to ignore SegWit transactions?

texts: Regular transactions can be ignored. What about SegWit transactions?


texts:
I have the Bitcoin Core client installed on my desktop, and I have encrypted it and backed up the wallet. I rarely, if ever, go into it. I just thought I would bring it up today and it now shows a 0 balance (instead of what was in there).

The last transaction was a series of small debits, that I didn't initiate, that appears to have wiped my account out. What happened? What can i do? Anything?

I have a transaction ID, but no mention in the program of where they went.


texts: need advice for Python interaction with bitcoin-core wallet

texts:
I've read about a few Python libraries that performs JSON-RPC calls to bitcoind. However, not many are actively developed/maintained, nor are they widely used in production environment. Since bitcoind evolves over time, these hard-coded Python functions may not work well with all the different versions of bitcoid -- some new functions are added while others may get deprecated.

And for any general purpose JSON-RPC library, we basically need to write all the wrappers of the function calls. It shouldn't be hard, but itself is another project.

I could've just use bitcoin-cli and let Python do subprocess calls, then the problem comes with parsing those stdout. Most of the time, they are just JSON format, except when they are not ...

Question: can anyone recommend the best solution for Python program to interact with bitcoind?


texts: Is there a Trading API that spans multiple independent sites, preferably from open source websites?

texts:
To experiment a little with automatic trading I'm looking for a trading api (like mtgox has) which is used on multiple independent websites so that if one goes under that I then don't have to redo my whole program. If possible one from open source bitcoin trading websites so that I can setup one in a vm and use that to test against.

I'm currently running my tests against Mt.Gox but that can be a bit expensive when the script doesn't perform too well.


texts: Reuse air gapped Raspi used for seed generation?

texts: Would it be wise for an air gapped RasPi used for seed generation be used again online with a new micro SD card? Am i missing anything?


texts:
I want to spend 1 bitcoin, And I can reach this amount with 3 inputs.

for example:

1 input = 0.5 btc
PB mypubkey_1
PK mypkkey_1

2 input = 0.4 btc
PB mypubkey_2
PK mypkkey_2

3 input = 0.15 btc
PB mypubkey_3
PK mypkkey_3

which private key use to Sign this transaction?

I will use mypkkey_1,mypkkey_2,mypkkey_3 or parent private key or something like that?


texts: Is possible especify the keys rather how many in multisignature wallets?

texts:
I search about multisignature wallets, but it seems very limited. Far I understand, we can create a wallet with N keys, and specify how many keys is needed to create a transactions.

So, I can create one wallet with 5 keys (K1, K2, K3, K4, K5) and I can specify how many keys (but not which keys!) are needed, so is possible to say: “you need 3 of 5 keys”. However, it makes a K1 + K2 + K3 and K5 + K4 + K2 a valid signature.

It’s possible to specify that which keys are needed rather than how many?

Imagine that have three people (K2, K3, K4) and have a server (K1). Only with K1 + (K2 or K3 or K4) will be valid. It means that K2 + K3 or K4 + K3 can’t be able to create a valid transaction. To be a valid signature we need two signatures, but one of that two need to be the K1.

It’s possible?

One alternative is creating a multiples multi-signatures wallets. I mean, create three addresses one with (K1 + K2), another with (K1 + K3) and so on. But, it will have multiples address, it is what I'm trying to avoid. Another solution is need all keys (4 of 4), but it will need the signature of the three clients, but it’s not easy and will need to wait everyone sign it.

For the background of the history, I trying to use the OP_RETURN. Everyone can access one single address and view all the information, about the three clients. The OP_RETURN value will be generated by the server (K1) and need to be signed with one of the client (K2, K3, K4). But, the client itself can't be able to create a transaction alone, so K2 + K3 need to be an invalid signature.


texts: What will happen to bitcoins stored at segwit outputs pre-BCH-fork?

texts:
If I understand correctly, P2SH-P2WPKH outputs are simply anyone can spend outputs in BCH.

What would have happened to BTC stored in such SegWit outputs BEFORE the fork, assuming that those addresses had sent several transactions also BEFORE the fork.

In this case, anyone can scan the blockchain and "steal" the bitcoins, despite there being no fault of the person who had those bitcoins.


texts:
Trying to request private data on GDAX but keep getting bad request. Cannot figure out what I am doing wrong. Please help.

private static JsonObject getAuthenticatedData() {
        try {

            String accessSign = getAccess();
            System.setProperty("http.agent", "Java Client");

            URL url = new URL("https://api.gdax.com/accounts");
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setRequestMethod("GET");

            con.setRequestProperty("CB-ACCESS-KEY", "accesskey");
            con.setRequestProperty("CB-ACCESS-SIGN", accessSign);
            con.setRequestProperty("CB-ACCESS-TIMESTAMP", ""+System.currentTimeMillis() / 1000L);
            con.setRequestProperty("CB-ACCESS-PASSPHRASE", "passphrase");
            con.setRequestProperty("Content-Type", "application/json");

            con.setConnectTimeout(5000);
            con.setReadTimeout(5000);

            String status = con.getResponseMessage();
            System.out.println(status);

            BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
            String inputLine;
            StringBuffer content = new StringBuffer();
            while ((inputLine = in.readLine()) != null) {
                content.append(inputLine);
            }
            System.out.println(content);
            in.close();

            con.disconnect();

        }catch(Exception e) {
            e.printStackTrace();
        }
        return null;

    }

And this:

public static String getAccess() {

    //Set the Secret
    String secret = "secret==";
    //Build the PreHash
    String prehash = Instant.now().toEpochMilli()+"GET"+"/accounts";
    String hash = null;
    try {

        Mac sha256_HMAC = Mac.getInstance("HmacSHA256");
        SecretKeySpec secret_key = new SecretKeySpec(secret.getBytes(), "HmacSHA256");
        sha256_HMAC.init(secret_key);

        hash = Base64.encodeBase64String(sha256_HMAC.doFinal(prehash.getBytes("UTF-8")));
         hash = hash.replace("\n", "");
        System.out.println(hash);
       }
       catch (Exception e){
           e.printStackTrace();
       }
    return hash;
}


texts: How to solve Blockchain 20 address gap-limit problem?

texts:
We currently offer Bitcoin withdrawals and deposits on our website. Blockchain API is used to handle all operations.

Only problem is Blockchain Receive API's 20 address gap limit, as mentioned here: http://bitcoinx.io/news/articles/blockchain-info-updates-receive-payments-api-version-to-address-edge-cases/

Now we get a lot of curious users who click on Bitcoin deposit button and commit to it without actually sending any transaction, which easily build up to 20 addresses. What are some ways of removing this limitation? I have few ideas but they are rather bulky and some require complete re-write of code and replacement of Blockchain API. Can you guys offer any insight and/or advice? How can this problem be solved in elegant and efficient way?


texts:
I have a BigInteger that represents a private key. How can I get that private key as a base58 encoded string? The following pseudo code does not work properly:

base58.encode(bigInt.toByteArray)
// yields a string that differs from given bigInt's private key

UPDATE

def fullDoubleSha(bytes: ArrayOfByte) = {
  val digestSha = MessageDigest getInstance "SHA-256"
  digestSha digest digestSha.digest(bytes)
}

def getPrivBytes(key: BigInteger) = key.toByteArray match { case keyBytes =>
  val res = if (keyBytes.head == 0) keyBytes drop 1 else keyBytes
  new Array(32 - res.length) ++ res
}

def privBytesToWif(vs: ArrayOfByte) = {
  val rawPrivKey = Array(0x80.toByte) ++ vs
  rawPrivKey ++ fullDoubleSha(rawPrivKey).take(4)
}


texts: If I send bitcoins from my wallet to an address I created in my wallet, will I get more than 1 confirmation eventually?  And do I have to wait for all the block to be downloaded to my wallet so I can get coins sent to me?


texts: My OMG wallet on Yobit.net is in maintenance. I get this message when I try to withdraw or lodge to the wallet. Why is this so?


texts: Will 64-bit miners work on 32-bit machines?

texts:
I want to distribute some miners, but I prefer not to distribute 2 versions of everything (32-bit and 64-bit).

According to Microsoft, most 32-bit programs run on 64-bit systems. I'm not concerned with that as much as an efficiency drop; will 32-miners be half the optimal speed on a 64-bit system? Additionally, many miners (cgminer/cudaminer) require drivers to be installed; these would obviously have to be 64-bit.

So, should I distribute only one version of the CPU miner (minerd.exe) or will that cause problems or a lack of efficiency?


texts: bitcoind: How to generate new address and broadcast?

texts:
I have my own server running bitcoind. Could you tell me how to generate new bitcoin address, sign and broadcast? My goal is that I can see the generated address's balance on Blockchain.info. As for you, my question may be very easy but I am looking for the way for a long time...

bitcoind's version is 0.9.2.

$ bitcoind getinfo
{
    "version" : 90200,
    "protocolversion" : 70002,
    "walletversion" : 60000,
    "balance" : 0.00000000,
    "blocks" : 335538,
    "timeoffset" : -1,
    "connections" : 21,
    "proxy" : "",
    "difficulty" : 39457671307.13873291,
    "testnet" : false,
    "keypoololdest" : 1418654127,
    "keypoolsize" : 101,
    "paytxfee" : 0.00000000,
    "relayfee" : 0.00001000,
    "errors" : ""
}


texts: Is there a central repository that states a country's latest policy on bitcoin?

texts: The legal status of bitcoin changes from country to country, to include a wide range of policies from acceptance to outright banning it.


texts:
I know this would not be possible but in-case someone just decided to try it out or accidentally put a high transaction fees (more than 12 bitcoin), so what will it happen?

Will the block reward increase or the remaining fees removed or will it not even send to the block?


texts: What are the drawbacks (if any) of encrypting your wallet with Bitcoin-Qt?

texts: Basically, is there any reason not to encrypt your wallet? The only drawback I can think of is forgetting your passphrase and losing access to all your bitcoins.


texts: Configure esplora to point to the bitcoind servers ip address

texts:
I have 2 servers running:

Ubuntu 18.04 running bitcoind daemon (v0.18.1 full blockchain synchronized)
Ubuntu 18.04 running esplora (the local single page website works, but it has no data from the local blockchain)

Both servers are on the same network.

How do I configure esplora to point to the ip address of the bitcoind server?  I would like to use my own full blockchain and explore it with esplora, aka a personal blockchain explorer.

The bitcoind server is already configured and working.  So the only part remaining (I think) is to configure esplora to point to the bitcoind server.  I can't find any clear instructions on how to do that.


texts: Is it possible to "unmine" particular coins?

texts: Imagine that a government seizes a large amount of bitcoins in a raid such as with "Silk Road". Is it possible to invalidate those particular coins and send them back to the "pool" to be re-mined so that that government cannot profit from the seizure?


texts: What are the implications of a decreasing trend of MtGox "ask" depth compared with "bid" depth?

texts:
The "Mt Gox Order Book Depth" chart at the bottom of the page at http://bitcoinx.com/charts/ currently looks like this:

Since mid May the red line on the chart ("Ask sum") has a strong decreasing trend, whereas the blue line ("Bid sum") has stayed steady.

What the implications of this?


texts:
Folks, I've been mining with a locally setup p2pool setup using bitcoind v0.9.0rc1-beta, p2pool version 13.4-14-g7aa75ce-dirty and bfgminer on another host. Been mining for about 7 months with 6GH which paid about 80m overall.

In the past few months, the global pool has grown to an insane 3.2 Peta and the payout dropped to nothing at all. I did upgrade to about 65GH a couple weeks ago which obviously is still a drop in the water. There has been zero payout over the past 2 months even though the local DOA is low (mostly less than 5%, typically 4). The point is that in 7 months, there's been 28 total shares found with 3 orphaned and 5 dead.

There are plenty other articles here talking about p2pool not being best for "low" hash rates. Can anyone recommend fair alternatives? There's another post here that explores a patched version of p2pool with adaptive difficulty and there are other pools which claim to remain decentralized (eligius and bitpenny).

Would anyone care to share their luck (or lack thereof) with p2pool and or other alternatives?


texts: Building cryptocurrency exchange behind TOR

texts: quick question, I don't have much experience with TOR(actually nothing), is it reasonable to build a mobile cryptocurrency exchange, which servers are behind TOR, so that's hard to attack for hackers ?


texts: Can miners reject transactions from an address?

texts: It is alleged that the stolen Bitstamp coins are in this address. In theory, could miners agree to reject all transactions from this address? And if so, would all miners need to agree or just more than half?