texts: How to compile Bitcoin-Qt as an .exe on Ubuntu?

texts:
After struggeling with the dependencies for a while, I finally managed to compile Bitcoin-Qt on my Ubuntu machine. I used the following commandos for compiling:

./autogen.sh
./configure -with-gui
make
sudo make install

Now when I write bitcoin-qt in the terminal, the wallet will succesfully start. However, I am not able to locate bitcoin-qt.exe on my computer. I want to be able to get the .exe and put it on other machines without having to install all the dependencies on them as well. How would I go about creating this .exe?


texts: Does the bitcoin URI message parameter have character limits?

texts: Is there a limit to how many characters are allowed in the message parameter of a BIP21 URI? I tried searching on the subject, but found nothing about it.


texts: Practical way to split a bip39 seed into a 2 out of 3 factor auth?

texts: I want to keep off-site paper-backups of my seed, but that increases the risk of a physical attack. Can I somehow split my Mnemonic Code into three parts that I only need two of to recover my trezor?


texts: Is the RAM or the computing power more important for the hashrate?

texts: I have done my research on the internet and failed to come up with any suitable answer. I asked on a few forums as well, but no results. So my question is, if I have two separate computers, one with 8GB dedicated RAM with a 1.7GHz processor, and another with 2GB RAM and a 3.2GHz processor, which one has the greater hashrate?


texts:
I am developing a program that monitors transactions.
The first question is how can I know there is a new transaction? I can consider the command listtransactions. However, there is a bit of an issue about this command which I posted in another thread. In short, I can't list transactions from all accounts by NOT providing the account parameter.
Even if it works for me. The API says:
listtransactions    [account] [count=10] [from=0]    Returns up to [count] most recent transactions skipping the first [from] transactions for account [account]. If [account] is not provided it will return recent transactions from all accounts.

I ran this command with parameters: "", 1,3. I still got the first 3 transactions.

Does anybody have a better idea about how to get new transactions that have not been checked?


texts: What is the worst an attacker could do with full control over the blockchain?

texts:
Let's assume somebody gains control over 100% of the hashing power and is now free to mine and control as many new blocks as he wants. What would happen?

The attacker still could not include any fake transactions into his blocks, because other nodes could easily detect that the transaction wasn't signed by the wallet owner.

The attacker could include some double spends from his own wallets, but again, this could easily be detected.

So, the other nodes would simply ignore his blocks as invalid. Maybe they would crash and require a fork, or they would recover and wait for the next valid block to be mined and broadcast.

It seems to me that there isn't really anything to gain from controlling the hashing power. Am I msising something?


texts: What is the best way to recover from an accidental double-spend?

texts:
Came across an issue where I was given the message:

"Error: The transaction was rejected.  This might happen if some of the coins in your wallet were already spent, such as if you used a copy of wallet.dat and coins were spent in the copy but not marked as spent here."

It appears that the 2nd amount was deducted from my total balance even though it still sits at 0/unconfirmed status days later even though the unconfirmed transaction has disappeared from the blockchain.

Any suggestions?  I've also installed Python and tried running a script provided by someone else (within Windows 7) and cannot seem to get the script to run properly.

Any help is greatly appreciated.


texts: Creating empty blocks vs creating full blocks

texts:
I've already read many different answers to this topic.

Is it correct that the miner decides on his own if he includes any transactions in his block and how many (as long as the block size is <1MB?)?

What is more beneficial for the miner and why: Creating an empty block, or creating either a block that contains all transactions of the pool/or <1MB? Or is there an optimum?

Isn't it faster for a miner to not include any transactions in order to get the reward? Even more, if a large mining pool did that, isn't there the danger of taking over the network?


texts:
How to generate Zcash address and private key by a mnemonic seed, in nodejs or python?
Is there some lib like bitcore-lib or ethereum-bip44?


texts: How many transaction and btc have been cancelled?

texts:
How many btc have been transferred in orphan blocks, but then never included in any later block? How many btc have been transferred in zero-confirmation transactions that have never been included in the blockchain? How could one find this info?

This would be an upper bound on the amount of fraud done by reversing transactions.

The first is an upper bound on the amount of fraud against people who wait for 1 confirmation, and the second is an upper bound against people who don't wait for any confirmation.


texts: What does the value of bitcoins depend on?

texts:
I've been looking up stuff about bitcoins for some time now and i have two question stuck in my mind:

How is the value of bitcoins so unstable?

And can there be bitcoin inflation?


texts: As the entire blockchain gets much larger, it will be impractical for ordinary users to maintain all of it. Will it be maintained by a diminishing number of powerful systems, and would that create an opportunity for collusion and fraud?


texts: How should I calculate a net value after a BTC withdrawal from an exchange?

texts:
Many exchanges have a withdrawal fee (such as Poloniex, which charges customers in 0.0005 BTC on average) and these fees are mostly for network costs.

Should I consider as a general rule that the net value of a cryptocurrency withdrawal is amount - withdrawal fee - network fee or just amount - (withdrawal fee OR network fees) if an exchange doesn't have these fees explicit?


texts: bitcoin payment processing, using bitcoin uri

texts:
I am interested in processing bitcoin payments in my application.
I read about bitcoin uri, but its unclear to me how to match the payment transaction to a specific 'user id' in my application?
Is it possible to include the 'user id' on the tx? is it recommended?


texts: Does any university accept bitcoin to take course fee?

texts: Which universities of the World accept bitcoins to take their course fee? Can it be done by bitcoins? I need to know it as I am planning to take some courses for higher education from an reported University.


texts: How old should be my bitcoins to send them again without transaction fee?

texts:
I'm making some test for a bitcoin merchant webpage. I want to test different actions without paying transaction fees everytime, but I can't since I use the same few bitcoins for everything.

Sooo how long should I wait for my bitcoins to be transfered wihout fee?


texts: incorrect teredo ipv6 address advertising

texts:
I have an issue with teredo addresses. After network issues or router reconnect the teredo tunneling interface address changes but bitcoind stays still unaware of it and continues to advertise the old (incorrect) ipv6 address.
Should I raise the issue on github on this?
Can somebody check if this exists on regular (not teredo) ipv6 interface?

Thanks.


texts: How do I add two secp256k1 keys together?

texts:
I have two public/private keypairs, A and B. I want to add them together to get a new keypair AB.

I'd also like to be able to add the public keys of A and B to get the public key of AB.

How do I do this?


texts: What is the api function call to access NXT's Data Cloud feature?

texts: If I hosted a few files on the NXT's Decentralized Data Straoge Cloud, how can I access those files via an API?


texts: Why are `update_add_htlc` and `commitment_signed` separate messages?

texts:
BOLT #2 indicates that a node will send one or more update_ messages before a subsequent commitment_signed.
Since it seems like sending a payment over a channel involves update_add_htlc followed by commitment_signed (without needing a response from the peer in between), why do these need to be two separate messages?


texts: Run a full node with multiple IP addresses

texts: I run a full Bitcoin node on a powerful server however rather than setting up multiple I was wondering if it's possible to use multiple IP addresses on one installation and one running process? Without people being able to detect it's the same node (not easily anyway).


texts: How long would it take to break a 32 bit key / encryption

texts:
I was actually wondering...
How long would it take to crack/brute force a 32 bit key/encryption and a 16 bit key/encryptions respectively?


texts:
I am trying to compile litecoind on Ubuntu 15.04 and I stuck here:

/litecoin/src$ make -f makefile.unix USE_UPNP=-
make: makefile.unix: No such file or directory
make: *** No rule to make target 'makefile.unix'.  Stop.

I found some a little bit different ways to compile litecoind, but every time I have problems with "makefile.unix". Can someone help me?


texts: I have/had 31 bitcoins on MtGox; What are my options now?

texts:
After reading the joint-statement on blockchain, and the fact MtGox is down now, I am scared, what are my options? Is there anyone who can help me in my situation? I purchased those coins for 800$.

Edit:
MtGox files for bankruptcy protection. What is the difference between bankruptcy and bankruptcy protection? I don't know, but I don't think that I am going to see anything from there...


texts: Is it possible to run both bitcoind and bitcoin-qt as backend and frontend?

texts:
Multiple instances of bitcoin-qt store the blockchain data separately causing lots of waste of storage and network.

I'm thinking of running bitcoind as a local server which stores the blockchain and each bitcoin-qt as a client that handles only the wallet data and connects to the bitcoind when needed, so that users don't need to wait until the chain is synced whenever they run bitcoin-qt.

Is this configuration possible? Ive read docs saying bitcoind and bitcoin-qt shares common sources but found no further instructions.


texts: Implicit/Tacit mechanisms in Bitcoin Core disclosing Selfish Mining

texts:
I'm referring to the selfish mine attack described by two researchers from Cornell University who describe a "possible" attack with lower than 51% hashing power.

Now it's interesting to know what sorts of mechanisms, changes were implemented into the new versions of Bitcoin Core that detect selfish mining, propagate some alerts, disclose suspicious forks etc.?

EDIT:

Obviously peers get to know about other peers' progress on the blockchain through data messages, in particular through updates via inv messages.
Are there other types of "messages" exchanged - without the knowledge of the node itself - that would give away secrets about a longer private blockchain, in this case?


texts: If newly generated coin disappear, will that affect the total supply?

texts:
When coins are generated they need to go down certain number of blocks to be mature and spendable, if for some reason they disapear, will that reduce the total supply of the currency, since the generation of new coins is the solving of some math and new block has uncovered some coins?

To make my question more clear, I've added this additional explanation:

What happend is that a month ago I found a block with new coins while mineing (in my case I wasn't mineing bitcoin but I think the concept applies also to other cryptocurrencies). I had problem with my internet connection and after a while I lost connection. When I solved the internet connection problem the newly generated coins that poped up were no longer there. If the coin supply is limited to 21M, then those coins should vanish forever as they were generated from the solving of the math problem that allows the creation of new coins. If that is the case then these coins should be lost forever, otherwise it means that every time a block containing coins is lost then another one is generated to keep the "total supply" 21M.In order to say that the total supply is limited there should be a limited number of blocks containig coins totaling the announced supply, in case of bitcoin 21M.


texts:
What is a solid amount of fee for a 100 Euro transaction right now?

I have googled myself but the results were quite confusing to me.

I've had a bad experience with my last payment due to a low fee, so I don't want to go along that road again...


texts: Is there a way to import a private key already protected with the passphrase?

texts:
Let's say I have a hot wallet that has passphrase encryption enabled.  Then let's say a large withdrawal needs to occur but the hot wallet has insufficient funds and a transfer from cold storage is needed.

If that is a spend transaction from cold storage, then those funds cannot be sent from the hot wallet until after one confirmation.  So the withdrawal request isn't served immediately and instead possibly is delayed by tens of minutes.

If I have an address that already has confirmed funds, and import that into the hot wallet then that can be used for spending right away.  But let's say I don't want to transfer the private key unencrypted to the hot wallet.  I'ld like to simply transfer the private key which has already been encrypted and import that.

Is it at all possible to do this?


texts:
Is 12-word seed phrase (as used by Electrum for example) safe enough for generating an offline wallet?

My understanding is this: 2048 words pool make 11 bits of entrophy per word. 12 words in seed make total 132 bits of entrophy.

Is this considered safe enough?

I'm not talking about being quantum-computing-resistent, just being infeasible to crack using brute force given the expected computing power in the foreseeable future.


texts:
When I tried accessing https://www.bitaddress.org with Firefox, I was redirected to https://www.bitaddress.org/bitaddress.org-v2.7.2-SHA1-364542f1ccc5777c79aebb1692a6265cf3e42e7e.html and got a security certificate warning:

The same redirection happened with Chrome, without any security warnings.

Is there a real security problem with bitaddress.org?


texts: How do Lightning channels interact with the blockchain?

texts:
Does opening a channel mean that a 2-to-2 multisig address (3xxxx) is created? And then both parties put money into the address? What if someone pays money to the address on main chain while the channel is open?
Does closing a channel mean that a transaction is made which splits the money based on agreement:

multisig: signature1,2(preTran) redeemscript

outputscript:  pay to A
               pay to B


texts: Private Brain Key Generation and Public Address Not Matching Java

texts:
I am trying to generate a public and private key set from a input string in Java. (Yes I am aware this can be a dangerous practice) I am using bitcoinj for a outside library.

I currently have:

 //public key generation from private key
 static String getPublicKey(byte[] privKey) {

    Address address = new Address(MainNetParams.get(),
        Utils.sha256hash160(ECKey.fromPrivate(privKey, false).getPubKey()));

    return address.toString();

  }

 ///hash string to generate private key from string
 static byte[] sha256(String base) {
      try{
          MessageDigest digest = MessageDigest.getInstance("SHA-256");
          byte[] hash = digest.digest(base.getBytes("UTF-8"));
        return hash;
      } catch(Exception ex){
      throw new RuntimeException(ex);
      }
    }

 //encode private key as string to display
 static String privToString(byte[] hash) {

      StringBuffer hexString = new StringBuffer();

      for (int i = 0; i < hash.length; i++) {
          String hex = Integer.toHexString(0xff & hash[i]);
          if(hex.length() == 1) hexString.append('0');
          hexString.append(hex);
      }

      return hexString.toString();

  }

When I run the following:
Seed String: icecreampaintjob

I get the following:

Public: 1KdoiXMYFn2qa8uGGiNqfrwFRDu3j2qQNA

Private: dba1e3e22415c56af772dee422add21b7382ea35f2af77852a8069d02e47ecf4

Using bitaddress.org to cross verify I get:

Private: 5KV1o7tRK8pNqrPNYyi38nrik9r2Y85sjdgFDttnDiT1uZrQ1fj (DOESN'T MACTH)

Public: 1KdoiXMYFn2qa8uGGiNqfrwFRDu3j2qQNA (MATCHES)

What am I missing?


texts:
I am trying to get my private key out of my Trezor in order to access my Litecoin cash.
I used the following site in order to generate the private key out of my 24-word recovery phrase: https://coinomi.com/recovery-phrase-tool.html

Many addresses get generated out of it. When using any of these keys into the LitecoinCash core wallet (ie. import private key), I am being asked for my passphrase (supposedly word 25th if ever set up, which I did not) and cannot access my Litecoins. I guess I am not generating the correct private key!?

Any advice on how to extract these Litecoin cash out of it?

Cheers


texts:
I'm really looking forward to the Lightning Network and all the efforts being put in by Blockchain.info, Blockstream, and others. But I was wondering if there aren't other options for decentralised scaling besides LN?

In particular, are there are other decentralised+offchain scaling models that have been suggested beside hub-and-spoke?


texts: Bitcoin core does not produce a wallet at all

texts:
I'm reading tutorials on working with bitcoin core like this:

http://bitcoindaily.org/bitcoin-guides/bitcoin-core-tutorial/
and
http://bitcoindaily.org/bitcoin-guides/how-to-recover-bitcoins-bitcoin-core-wont-sync-export-private-key/

Both of which suggest the use of bitcoin core should produce a wallet address of some kind automatically.  Specifically, the second says:

  Bitcoin core automatically generates your first bitcoin address for
  you but you can create as many new ones as you want.

I can't seem to get a wallet address to get started.

Where there is supposed to be a wallet address there is none, and I am asked to enter one, but how do I get one in the first place?

Here is what I see:

There is no address, and I can't just guess one---anything I type in the Address box says it is invalid.


texts: How this is possible to generate blocks with no transactions?

texts:
I found this block in blockchain explorer. It is pretty well confirmed, but it has no transaction inside, except "Newly Generated Coins" one. How this can be possible and what for?

Additional question: If this is so easy to generate such blocks, what stops miners to generate these (lightweight) blocks as many as possible to earn new bitcoins? Thanks.


texts: Bitcoind live wallet backup (by copying wallet.dat)

texts:
Is it safe to copy wallet.dat while the daemon is running, or should the daemon be stopped before doing so?

I'd imagine it would be safe unless addresses are being generated exactly at the same time.


texts: What portion of the mining process does an ASIC perform?

texts:
If ASICs were described as a black box, what would their inputs be?

Obviously, the actual hashing, the churning of the SHA-256 function is performed by the ASIC. Also, they must of course be able to tell when they have succeeded, so they must have a mechanism to store and compare the target to their result.

Yet, how much of the pre-processing steps do ASICs perform? I would assume that they increment the nonce, as it is raced through in less than a second and perhaps the extra nonce? Can they change the timestamp? Do they manage the complete block header? How much of the block header do ASICs vary by themselves?

Do ASICs assemble their own blocks?


texts: How could an LN node acquire inbound liquidity? Is there any systemic risk?

texts:
I once heard that LN could support dual-funded channels. It doesn't seem so complicated, but currently, I don't know any LN wallet which supports creating dual-funded channels.

By the way, I'm also concerned about security: will dual-funded channels introduce systemic risks/attack vectors? For example, if an attacker is already able to do a 51% double-spending attack, could he leverage the inbound liquidity to multiply his profit?


texts: Can I see transactions in bitcoin-qt without downloading blocks? if I have a server with blocks on the local network?

texts:
I have server with bitcoind (synchronized), port 18443 opened. And I tried to connect to rpc server with bitcoin-qt in my mac. With this configuration:
regtest=1
rpcuser=<login>
rpcpassword=<pass>
rpc_connect=<ip to server>

But bitcoin-qt writes that it is synchronizing, and to use the application you have to wait.
Can I use bitcoin-qt without synchronization?
P.S. Sorry for my english


texts:
I did some google searches but I can't really understand much about what exactly is being mined.
I know people use computers to solve problems for others? But what problems exactly? And who pays them? And why don't they just pay in real money or are bitcoins being created out of nothing?


texts: Why is slush pool showing my worker as off?

texts:
I've recently started mining with slush pool, I've also tried antpool yet on both mining pools it shows that the worker is off. I am very experienced with computers and have already setup port forwarding. I realize this is a duplicate question but I feel I need a personalized answer, my hash rate is around 233.2Mhash/s. if this does not meet the minimum requirement, could someone please point me to a pool with a lower requirement. Please let me know if you need any logs or system specs. to solve this problem. (Yes I realize mining with GPU is obsolete although I lack funds to invest in a professional miner.)

Thanks in advance,

Jake


texts:
With the upcoming UASF activation what do I need to do to come out okay? I have my coins sitting on my Trezor in cold storage.

If I just leave them as is, what happens?

If I switch my Trezor to UASF, what happens?

Do I get coins from both chains? Do I need to pick one before August 1st?


texts: RPC call to get unconfirmed balance on a watch only wallet

texts:
We have a bitcoin core client running on a production machine. This machine cannot have the private key so each address is added as watch only.

So far it has worked perfectly, but recently we need to display the btc amount that is waiting confirmation and the amount that is confirmed (at least 1 confirmation)

bitcoin-rpc getbalance * 0 true
bitcoin-rpc getunconfirmedbalance

these are the two methods that I've found online that should work, but they are not working.

getbalance returns only the confirmed amount and getunconfirmedbalance returns always 0

How can I get the unconfirmed balance on a watch only wallet?


texts: HELP BITCOIN SENT CONFIRMED BUT I NEVER RECIEVED BEEN 2 DAYS

texts:
help im not sure what to do i sent from Pax, bitcoin like i have done many times and it shows up as confirmed, but yet i dont see it at all heres the id 7581e42bf71df4b81fdb233542f3e0baeddeb60bd5e11361b1f8cb7ccb3553a5

is anyone able to help me recover this? or is it gone for good?


texts: Allowing Incoming Connection on Bitcoin Core

texts:
Good Evening,

I recently installed Bitcoin Core v0.12.1 on my home server (running Windows 7) and wanted to allow it to accept incoming connections and used the guide found here: https://bitcoin.org/en/full-node#windows-7 to ensure I did everything that was needed.  Unfortunately, it hasn't been showing any incoming connection and when I used the connection tool recommended in the guide (https://bitnodes.21.co/#join-the-network), it says my server is unreachable.

I have already setup port forwarding for port 8333 to both my server's IP address, 192.168.1.105 (wireless) & 192.168.1.129 (ethernet).  I ran a port scan on the following websites and they all indicate that Port 8333 is open:

Ping.eu Port Check
WhatMyIP Port Scanner
T1 Shopper Port Scanner

(I would provide links for the above scanners, but I cannot post more than 2 links)

I also created two rules in Windows Firewall (under Inbound Rules) with the following properties:

Local Port - 8333
Remote Port - All Ports
Scope - Local & Remote IP address set to Any IP Address
Domain, Public, and Private all checked
All programs that meet the specified conditions checked
Set to allow the connection
Rule is enabled

There are two rules with the above settings, one for TCP and one for UPD.  Even with all the above setup, the "Join the Network" tool on Bitnodes website (second link from the top) still says my node is unreachable and the debug window inside the program shows 0 incoming connections and 8 outgoing connections.

I'm not sure what else needs to be setup since I completed everything in the guide and port 8333 is definitely open.  Any help or information with this issue would be greatly appreciated.  Thank you in advance.

Dominick


texts: How will the new Internet Neutrality Act affect Bitcoin?

texts: How do you think the neutrality act that is being talked about as I write this post will affect the Bitcoin community. Not only in transactions, but mining, how will it affect Bitcoin economically with users and miners alike all on the same network? Can someone give the pros/cons to this question. Also, how could this propel bitcoin positively in anyway? This could affect the whole world but I feel like it could have a huge affect on Bitcoin more than what people think.


texts: What happened to the stolen Mt. Gox Bitcoins

texts:
Since the stolen Bitcoins are 850 thousand, so roughly 4% of all Bitcoins, they must be quite noticeable.

Is it known to which wallet addresses they went?

Did they move from those addresses since? Where they sold through an exchange?


texts: Is it safe to delete bootstrap.dat.old? Because my bitcoin-qt is using the internet to synchronize right now ("Importing blocks from disk." stage has finished). But I still am not sure.


texts: I need help on a 24 hr unconfirmed transaction on blockchain

texts: If anyone can please help I transferred $254 worth of bitcoin to my coinbase account and it has been 24 hours now and it still has 0/3 confirmations so my money is just floating out there somewhere. I'm very confused because my first transaction literally took 20 mins and it was for about the same amount. Is everything alright or do I need to worry? I see people saying stuff about raising the miner fee but from what I have seen you can't do that once it has been sent. If everything is ok and I have nothing to worry about then that's great but I'm really starting to worry here. I thought bitcoin transaction were stress free but here I'am freaking out. I can't imagine if it was a big transaction what I would do. Please Help! Has this happened to anyone? Is this normal? How do I avoid this is the future or is this completely normal (because everything I read says 30 mins)? First time poster so please take it easy on me I would appreciate it. Thank You for your time


texts: Why will or will not the bitcoin infrastructure become unsustainable?

texts:
I am new to bitcoins, but as I understand the technology:

All transactions must be downloaded to the client machine (say, Grandma's Windows XP machine from 2003)
New transactions are also sent to all clients

Is that correct?

If 1 billion people adopted Bitcoin as their primary currency, and performed an average of 1 transaction per day each, this would be 11,000 transactions per second every day on Grandma's Windows XP machine.  I think it would catch fire!


texts:
Let's say you have a 15 second block time, and after your first transaction, your wallet's send button is frozen, and you have to wait for 2.5 minutes before you can send another transaction.

Would this prevent somebody from doublespending?

BTW: in case you want to ask how this could be enforced on the send button: Hmmmm maybe with something like scrypt which is timebased.


texts: BIP32 child derivation from another child

texts:
I have a bit of conceptual problem here,
Let's say I have a BIP32 implementation. If I derive two subkeys (1/2/1/2) and (1/2). is it possible to derive (1/2/1/2) from (1/2) with a subkey of (1/2)? I tried with chain_code and some other attributes but couldn't do so. by theory it should be possible to do so.

{
   "BTC_address_uncompressed": "1Pgi2HfASCtdVRNvX9HAtExenob1P5XtND",
   "address_uncompressed": "1Pgi2HfASCtdVRNvX9HAtExenob1P5XtND",
   "chain_code": "2b8efcd0870f61cac59eada4a1134a4f85d6817dc9a3dd7bf05f36e6c441a86c",
   "child_index": "2",
   "hash160": "392c59e21bc90f9c64ecc231db10cb04536277d6",
   "hash160_uncompressed": "f8d53bbd2c19a6ba9e8f35acecea7c37e31f80b1",
   "key_pair_as_sec": "02f9f02c77c6941f6352a2dd0a49964855ca239f008cd3be82532dacda0a3c79cd",
   "key_pair_as_sec_uncompressed": "04f9f02c77c6941f6352a2dd0a49964855ca239f008cd3be82532dacda0a3c79cd3872f468b85780e4bdcf377d8edf489598db1c2599cda0b850485fca2dbfb2cc",
   "netcode": "BTC",
   "parent_fingerprint": "1d6a6638",
   "private_key": "yes",
   "public_pair_x": "113050249498765822977324374771814145675507826911953945709948991807419582282189",
   "public_pair_x_hex": "f9f02c77c6941f6352a2dd0a49964855ca239f008cd3be82532dacda0a3c79cd",
   "public_pair_y": "25532626935404182358748554952372223106065623765752497625888032090220560102092",
   "public_pair_y_hex": "3872f468b85780e4bdcf377d8edf489598db1c2599cda0b850485fca2dbfb2cc",
   "public_version": "xpub6DkSjhJroC5HcnATQeZbdVZ2jFvWFvRqtayUJrc3H7GQeZJkKnn1BzdjDXyfYybctt38hyhz6zCdwWUAV6RnZqPone2ogmbTURBWsEFijgB",
   "secret_exponent": "21957517685205718377964087536472375993731742179518736675030422350744044394236",
   "secret_exponent_hex": "308b83bc8496fba96b299ca060f8c4cd15201aef14319891118facee42fb56fc",
   "subkey_path": "1/2/1/2",
   "tree_depth": "4",
   "wallet_key": "xprv9zm6LBmxxpWzQJ5zJd2bGMcJBE61rThzXN3sWUCRimjRmkybnFTkeCKFNFRCnqUsSAPB6AP38ENJNqzwmi51KxsUpNU5Rns3UwNCNw93VWi",
   "wif": "Kxr5MqcX6p1kCHLYhAtDA8dsuihHC3YJRfQfzrPUi9DZAbv1co8g",
   "wif_uncompressed": "5JBfbdPYk1EJwfbLR49RxYBd1ASthZkLopfttAq96F6ZfSXB2uK",
   "y_parity": "even"
}
{
   "BTC_address_uncompressed": "1CpmMHVTTn49351P4miiJZ6Wmw7rDJbg3z",
   "address_uncompressed": "1CpmMHVTTn49351P4miiJZ6Wmw7rDJbg3z",
   "chain_code": "566d6d36816b37d1bc9f0f926c1bcf48b9bf6c63154f65be05092a7ce0bac35d",
   "child_index": "2",
   "hash160": "387e7a981a85ded4ad332ac22400d542de38a978",
   "hash160_uncompressed": "81b1f48274c505147b5bf587db589062b1b69f5b",
   "key_pair_as_sec": "02c2f7da1cdc57f27e145a9fda472bfdc16cfc5b4ee32ee222413b0d88edc965f1",
   "key_pair_as_sec_uncompressed": "04c2f7da1cdc57f27e145a9fda472bfdc16cfc5b4ee32ee222413b0d88edc965f1a42ae022c788b0979dd88be456fd1c978ff3b0106799bc17de4cd46d17832970",
   "netcode": "BTC",
   "parent_fingerprint": "35a566ae",
   "private_key": "yes",
   "public_pair_x": "88186609208940930858580461894832276236539662740019279303523484605501248464369",
   "public_pair_x_hex": "c2f7da1cdc57f27e145a9fda472bfdc16cfc5b4ee32ee222413b0d88edc965f1",
   "public_pair_y": "74255061673209624574278121782459859935947830070827127273487212667373296494960",
   "public_pair_y_hex": "a42ae022c788b0979dd88be456fd1c978ff3b0106799bc17de4cd46d17832970",
   "public_version": "xpub6AAW9FwEvZaNLKtYTx1vFA1R1dVQv5GwTXwqgCg6GXq7E3fKVz7aaNGLFVcHH9LpWgqUpJ7FRFcibtRWzJ1WegqzZyynr66KxDLUPcpjRNK",
   "secret_exponent": "88370307846732603980165533658065807515286167433444038693954586861070917075377",
   "secret_exponent_hex": "c35fd25e084c54afae5c7a9942f1374780bd2b8a55e4148c5615ea2ed84c81b1",
   "subkey_path": "1/2",
   "tree_depth": "2",
   "wallet_key": "xprv9wB9jkQM6C257qp5MvUut24gTbevWcZ66K2EspGUiCJ8MFLAxSoL2ZwrQEahDCk2EugHxu5w6p5z6cHLdk9yE9bC5axxbaT49Ccs4UUPTzb",
   "wif": "L3mVYhLfDx23vrSRdWYQgk1Myqga4cFXVepcFJ4EQ774e5GRFHXB",
   "wif_uncompressed": "5KJL9zdB282beaQS4jwhFttHY19xyZ17uiCEspN87bTkRJEHtZH",
   "y_parity": "even"
}


texts:
Are there any implemented ways for turning addresses into human-readable word(s)? If not, why? I.e., are there any known technological issues in implementing this?
Thanks


texts: BIP 44 is scanning external chain really enough?

texts:
When reading the BIP 44 proposal I stumbled upon this paragraph about address discovery:

  We scan just the external chains, because internal chains receive only
  coins that come from the associated external chains.

Is it really enough to scan only the external addresses to recover the full transaction history? What if you are using the same wallet simultaneously on another device and it makes a new transaction using the internal (i.e. change) addresses as the only inputs?

Imagine having a new empty wallet and receiving 1 BTC to your first external address and making a 0.01 BTC transaction to somebody else subsequenly. The remaining 0.99 BTC (minus fee) would be sent to your first change address and subsequent transactions to other wallets could and would use as inputs only change addresses, so scanning the history of your external addresses when rcovering the wallet from zero would reveal only the first and second transaction you made with the wallet, not the subsequent ones.

Is it perhaps enforced to include an external address as a change address in the transaction if all the inputs are internal? What am I missing there?


texts: Bitcoin-qt doesn't get a server connection?

texts: I have created a new altcoin, and I run a server on one machine and connect bitcoin-qt on another machine. In this case it's blink the network connection, sometimes it shows one connection and after sometime it will disconnect and again show connected. What is the issue with that and how I can resolve that issue?


texts: Bitcoin public key — why do we have a compressed and uncompressed version?

texts:
My understanding is that the public key can start with 04 if it's uncompressed, or 02 or 03 if it's compressed.
What's the purpose of this?
It appears that you'd have greater entropy if it's uncompressed.
And if this is indeed the case, why would you want a compressed public key?
Wouldn't it be safer to use the larger one?


texts: scriptPubKey consisting of the only hash

texts:
I found out that some transactions have strange scriptPubKey in their outs. They only contain a hash and nothing more. An example can be seen in JSON-view of block 200639:

{
    "value":"0.00000000",
    "scriptPubKey":"7ce73474ecef1936fca45fe7835cca09d1a24f52526c189ab40d371b5f69f4a3"
}

The transaction is valid as the stack will only contain this hash which is not empty and thus evaluates to true. This seems to be a way to save some data in transaction...

Does anyone know for what purpose such scripts may be used?


texts: What is the computational power required for just verifying maybe two transactions

texts:
I want to know the amount of computational power required to verify a just a couple of transactions. No mining included, just verification
can it be done with CPU or maybe even phones?


texts:
After my boss read the websites mining on visits he got the idea to use the entire network we have access to. I have access to 3000+ computers and have been give permission to run a test over the weekend. Some of these computers have GPU's some don't. I would like to run cgminer with the --enable-cpumining flag to allow the cpu to work on the computers without GPU's.

when I use the tag

--enable-cpumining

I get

--enable-cpumining: unrecognized option

I think I am missing something here, any help would be great.


texts: Do pool servers check for duplicate shares?

texts:
Assume, for the sake of argument, that I am a miner and that I am ready to cheat. The (stratum) pool server sends me a notify message and I start mining. I find a valid share. I submit it to the pool server (which, presumably, checks if it is valid). Now, what happens if I re-submit it a little while later, in order to artificially increase my number of accepted shares?

So stratum pool server keep a list of submitted shares and check for de-dups? On large pools, where miners report a share every few seconds, this means keeping about 16kbyte of data for each miner, and scanning through it every time it submits a share. So it seems feasible.

But is it actually done?


texts: How does bitcoin and other cryptocurrencies price the value of the currency? How exactly does this work. Do buyers just set a max price at which they want to buy and sellers a min price at which they want to sell and they are matched? Or is there something more complicated at work? I'm really interested in understanding how this works. Any details would be much appreciated


texts: What is meant by "relaxed standards" for P2SH redeem scripts in Bitcoin Core 0.10.0?

texts:
From the Bitcoin Core 0.10.0 release notes:

  Standard script rules relaxed for P2SH addresses

  The IsStandard() rules have been almost completely removed for P2SH
  redemption scripts, allowing applications to make use of any valid
  script type, such as "n-of-m OR y", hash-locked oracle addresses, etc.
  While the Bitcoin protocol has always supported these types of script,
  actually using them on mainnet has been previously inconvenient as
  standard Bitcoin Core nodes wouldn't relay them to miners, nor would
  most miners include them in blocks they mined.

So essentially the core software will now relay more intricate P2SH Txns which would previously be deemed non-standards transactions.

What are the specific changes which have been made (ie relaxed standards)? Does it only apply to P2SH Txns? Finally, "n-of-m OR y" and hash-locked oracle addresses are mentioned as examples: what does this refer to exactly?


texts: How a transaction is permanently accepted by the blockchain?

texts:
If a miner A creates a block containing a transaction A and a miner B creates a block NOT containing the transaction A about at the same time, then some of the other miners will first receive the block of the miner A and the others will receive the block of the miner B. (Fork)

If the chain of the miner B grows faster than the chain of the miner A, then the transaction A will never be accepted (like it never happened). So, how the user A who created the transaction A can be sure that the transaction A was accepted/verified by the blockchain?

Also, is there a possibility that the transaction A is verified by the blockchain at some point and then in the future another subchain (from a previous fork) not containing the transaction A will grow faster, thus rejecting transaction A ?

Are there any time checkpoints created that all the miners should agree upon ?


texts: How is a node selected to run Smart Contract in Ethereum

texts: A node that runs a smart contract will be paid with GAS. How is this node selected? I guess this node should be trustworthy. Or multiple nodes are running the same smart contract just to make sure somehow?


texts:
An issue I find when I travel is that I would like to visit a cafe that accepts Bitcoin but because I am abroad I usually don't have an internet connection on my phone.
I could use WiFi but what is the best way to transact Bitcoin without internet at a point of sale? i.e low value transactions.


texts: Why won't a transaction with 888/byte confirm after 11+ hours?

texts:
I have this transaction that I can't figure out why it won't confirm.

https://blockchain.info/tx/92b33d498a35d47f03eee14f258cf9b3f015a5d12856eb05e47534e664344239

If I check https://bitcoinfees.earn.com/#delay it says with that it should confirm very quickly.

Thanks.


texts: Have the early mined coins been moved/transacted?

texts:
Has anyone done an analysis of the early coins mined by Satoshi and Hal Finney? Have those coins been moved/spent/transacted?

I wonder whether Satoshi has been cashing in on his collection or does he just let it sit there?


texts: Pay to script hash address transaction not accepted by miners

texts:
I have fixed my initial transactions and have been able to send coins to a p2sh address
Now I want to spend those coins but when I try to broadcast my transactions either the website (blockcypher) accept it and it is then later not accepted by miners or rejected (blockstream) with:

sendrawtransaction RPC error:
{"code":-26,"message":"non-mandatory-script-verify-flag (Extra items
left on stack after execution)"}

I think I have made the the correct ScriptSig for the 2 of 2 multisig (OP_0, sig1, sig2, redeemscript) so I am not sure of my error:

OP_0 3045022100e91708339615eb38326a5c513b5dcc040bf59a1b97faef2c1f59a7b16426519a02200a4ca9d8c9f05ec824c70d1564ae2952650bc0ddc8bce92f081dd7d29d33d7ea01 3045022100ca0e751242a6d33ab2e895a9b1d9e5dce18426f2d11e69009e794ebc1004ba1a0220022a95a3f335fd84b380d6482948c24817a9f021f0dea75689eccf59e1540ae901 2d5214a175b609a7c37011420585f1fcf392fdda9a025414b1e9f0fa01914ff497607f99bf90dbd8a41bd8bb52ae

And here is my full tx:

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

and the code I use to create it:
https://pastebin.com/c0EvKjPH


texts: How does number of transactions in the block affect it's mining time?

texts:
Does number of transactions in the block affect it's mining time?

How and why?


texts: What is the average bandwidth used by the default client?

texts: I am asking it because I'd like to install the client in my work office. Is that safe? I know the first time it take a long time downloading about 2 GB or more, but what is the daily normal activity?


texts: What happens if my transaction is not accepted because I did not pay fees?

texts: I was reading this thread about a client fork that does not force transaction fees and I noticed the big red warning saying that some coins might get lost if I am not careful. What does this mean? What should I do if my transaction is not accepted?


texts: Transaction fees after 0.9 protocol update

texts:
As the changelog of bitcoind 0.9 tells, transaction fees should be greatly reduced. What are the implications of this?

How were transaction fees determined before the change and after the change?
How does this change affect third-party software developers (who do not use Bitcoin-Qt wallet) - do they need to mimic this change?
How does this change roll across the network? Do 51% of miners need to update to the new version before the change starts to be effective?


texts: Missing bitcoin... over 6 confirmations!

texts: Ok, so I sent a vendor 0.0046531 bitcoins using Muun wallet. The address I sent it to is 3LTJzNzbXDBDdzHPxDSQk6sucLDKPW3zmN. The blockchain explorers I have used to track the money says they were received and “spent”, leaving the wallet with a balance of zero. Therefore I still owe the vendor money, but what happened? Is it fraud? I’ve used this vendor for years and something like this has never happened before.


texts: Understanding SPV, pruning and its downsides, as well

texts:
First of all, sorry by not asking an objective question, it's because I can't resume this one and I didn't find information even in the "mastering bitcoin" book. The large texts in this question are also to help people get in the context of what I'm asking.

Suppose I run a bitcoin client in pruning mode. As I understand, it'll download the entire blockchain, verify that the transactions are well formed, don't spend unexistent outputs, the signatures match, and the hashes of the block match. After that, it'll erase everything and just store the Merkle Trees of each block. I understand how a Merkle Tree works, it's a structure made of hashes of transaction IDs. Given a transaction and its merkle path, I can verify if the transaction is in the block or not.

If I just accept blocks from the network but did not previously verify the blockchain, I could be fooled to verify that a transaction is in the mined block, but I would not be able to verify if the transaction is well formed, if it spends unspent outputs, etc. So that's why the entire blockchain must be downloaded and verified before. (even though, it's unlikely that someone would waste hashpower to mine a block with an invalid input, but of course if we rely on unlikely, it would open a port for this possibility).

So, as I understand, an SPV client just receives the latest merkle root of the latest block and verify if a transaction is in it. It then see that very much hashpower was wasted on that block, and then assumes that it should be a valid block. Am I right?

In pruning mode, however, the entire blockchain is downloaded, verified, and then pruned. Now, the client just downloads new blocks, verifies them, and prunes them. As I've read, however, in pruning mode, the client maintains the latest x blocks for some reason. Why?

Also, if I have the entire blockchain in pruned mode, that is, a blockchain made of only merkle trees, given a new transaction and its merkle path, I can verify that it's in some block and I know that this block is valid because I validated it before pruning. However, how do I know that this transaction spends an unspent input? Do I need to ask for the merkle path of the referenced transaction and keep doing that?

In the current model in my head, I don't see how a pruning node could be fooled. Is the only downside of pruning nodes that they don't help the network very much? Because they can't provide merkle paths for those who ask, etc. But if I receive a transaction and I am a pruning client, can I have the same confidence as a full node that I'm not being fooled?

Is there any other disavantage of pruning that I don't know? I'm asking because I'm verfy intersted in this model and I want to run a pruning client.


texts: Generate keys/addresses for all altcoins

texts:
I'm looking for a library or method to generate addresses for as many of the most popular currencies/altcoins as possible. Is there a known library that supports this? Or do I need to use a specific client for each coin?

Thanks!


texts: Building Bitcoin from Source on MAC OSX 10.9

texts:
so I'm trying to get bitcoind running on my Mac and I cloned the source code from github. What I tried doing:

brew install autoconf automake berkeley-db4 boost miniupnpc openssl pkg-config protobuf qt libtool
git clone https://github.com/bitcoin/bitcoin.git
make

But then I get an error:

***No targets specified and no makefile found.

However, I'm looking and I see Makefile.am Any Ideas on what to do?


texts: If I have the hard drive that I mined bitcoins on, can I find the wallet?

texts:
I used to mine bitcoins years ago and I still have the hard drive. I just don't know where to find the wallet or the key or any of it.

Is there any way for me to do that?


texts: Access my wallet using a 16 digit passphrase

texts: I had a wallet years ago on a PC I sold. I mined bitcoin on it and what not. Recently I found a 16 digit passphrase I wrote down for my wallet. That is all I have and probably all I needed. If I only wrote down the 16 digit passphrase that means that's all I probably needed to access it anytime. I'm 99 percent sure I was using bitcoin core but I'm not too sure. What I do know for sure is that I have my 16 digit passphrase. My question is how can I access my wallet with my 16 digit passphrase I got?


texts:
I just downloaded Bitcoin on ubuntu and started as per the instructions in the README file. But, cannot understand the terms "Label", "Address" or any other for adding a new address or sending bitcoins or anything.

Can anyone help ??

Thank You !!!


texts: How do I pick the right cryptocurrency without becoming an expert in cryptocurrencies?

texts:
I live in a country where a certain national currency is used as legal tender. I do not understand how the local money works (e.g. how the national money supply is increased), nevertheless I can easily use it in my everyday life, for example to earn wages and pay for food. One factor that makes the local currency easy to use is that there is no alternative. In most circumstances I cannot pay with another currency.

Being interested in criptocurrencies, I'm faced with a difficult choice: Which currency do I want to use? Being an ignorant fool and unwilling to educate myself on how cryptocurrencies work—

How do I choose a cryptocurrency to use (and support)?


texts: Can the Large Bitcoin Collider project 'break' into offline hardware wallets like the Nano Ledger S?

texts: Let's say the Large Bitcoin Collider manages to guess the private key of a particular Nano Ledger S. Can they then 'spend' or 'steal' the Bitcoins on the Nano or 'send' them to another wallet?


texts: Is it possible to run primecoind as a server and connect other primecoin miners to it, so that they all mine for the same wallet (on the server) in parallel? A kind of solo mining in parallel. I am using v0.1.2.0xpm-hp11-unk-beta


texts: Which Exchanges Allow Short Selling/Margin Trades with USD/BTC or USDT/BTC

texts: I think Bitfinex did. But for example Poloniex has USDT & BTC but does not allow short selling with USDT.


texts: What happens in detail, when Bitcoin Core verifies a block during synchronization?

texts:
Since version 0.10.x, block headers are acquired separately, and therefore download is not delayed until previous blocks have been verified.

Previous questions about synchronization mention that the verification takes the most time: How does Bitcoin Core verify each block? I assume it checks each transaction's script, the merkle tree, and finally the blockhash, but how does that go in detail?


texts: Here is bash script that auto transfers from hot to cold wallet upon threshhold met. Do you see issues?

texts:
The idea is to run this via cron job at some interval and have the excess of funds transfered to cold wallet address.
So, I thought it will be easier to open source it so I can give it to the community and have it reviewed at the same time by more eyes.
It hasn't been tested yet. So, any issues you see?

#!/usr/bin/bash
BITCOINCLI="/set/path/to/bitcoin-cli"
MINIMUM_TO_KEEP=0.1
RECEIVERS_ADDRESS=xxxyyyyzzzbitcoinaddress

echo bitcoin-cli executable is: $BITCOINCLI

tempOutput=$(mktemp)
tempOutputErr=$(mktemp)
#echo "$tempOutput"
#echo "$tempOutputErr"
"$BITCOINCLI" getbalance > "$tempOutput" 2> "$tempOutputErr"

#echo "output file:"
#cat "$tempOutput"
#echo "Error file:"
#cat "$tempOutputErr"

outputsize=$(wc -c "$tempOutput" | cut -f 1 -d ' ')
if [ $outputsize -ge 1 ]; then
balance=$(cat ${tempOutput})
else
balance=XYZ
echo "Error: Could not connect to server. Or some other error while tring to find balance. "
rm "$tempOutput" "$tempOutputErr"
exit
fi

echo Balance is "$balance"

sendamount=$(echo "            $balance  $MINIMUM_TO_KEEP  - p" | tr '\n\r' ' ' | dc   )

#echo comp = "$comp"  x
if [ "$sendamount" > 0 ]; then
    echo "Balance is greater than the amount to be kept, which is $MINIMUM_TO_KEEP"
    echo Sending "$sendamount" BTC to the address "$RECEIVERS_ADDRESS"
    "$BITCOINCLI" sendtoaddress $RECEIVERS_ADDRESS $sendamount > "$tempOutput" 2> "$tempOutputErr"
    outputsize=$(wc -c "$tempOutputErr" | cut -f 1 -d ' ')
    if [ $outputsize -ge 1 ]; then
        echo Error while executing sendtoaddress. Could not send the amount. The error is:
        cat "$tempOutputErr"
    fi
else
    echo "Balance is less than $MINIMUM_TO_KEEP"
fi

rm "$tempOutput" "$tempOutputErr"


texts: What is the "hierarchical" about in Hierarchical Deterministic Wallets?

texts:
So, the advantage of deterministic wallets is that you can recreate all private keys from the initial backup you created.

What's the advantage of having a hierarchy branching out from the master seed, instead of just one line of key pairs?


texts: Possibility of fractions less than 1 satoshi in transaction fees

texts: I know that I can't send even 1 satoshi due to dust transaction prevention, but the question is - might the transaction fee be not e.g. 160 satoshis, but 160.1 satoshis?


texts:
Possible Duplicate:
  What is the status on webminers?

I love Bitcoin mining so far.

However, I need to do it without running a Java applet that I download {see BitMinter for an example of this} and without downloading a program.

Are there any Bitcoin miners that run from a web page and use the GPU? I couldn't find any.

Ideally, something similar to http://www.bitcoinplus.com/ but using the GPU with/instead of the CPU.


texts:
On my current OS I have daemons of bitcoin and other altcoins running in bitcoin there were 5 different addresses lets say

userA
userB
userC
userD
userE

userB has sent some coins to a address generated by him, and this transaction was covered in e.g block number 300 but my bitcoind was synced till block number 250 only. Now if I save wallet.dat and place it in the same folder after reinstalling the OS will this retainn the addresses generated by different users ? and after synchronizing to block 300 will those coins comes into the wallet ?


texts: Can I transfer money from my Deferred Compensation Plan to buy Bitcoin?

texts: I have money in a Deferred Comp plan and want to use it to buy Bitcoin.


texts: Why is Public Key aggregation in MuSig described as a product of the public keys?

texts:
In the the MuSig2 paper, it is described that:

Each signer randomly generates and communicates to others a nonce
Ri=g^ri; then, each of them computes R=∏ni=1Ri,c=H( ̃X,R,m)where
̃X=∏ni=1Xiis the product of individual public keys

I would expect that an operation of two or more points on an elliptic curve would be described as an addition operation, such as the sum of individual public keys {X1...Xn} (not the product of individual public keys). The paper describes the aggregation of public keys and public nonce values as a product. Am I misunderstanding the actual operation occurring here? Why is this the product of curve points?
In other words: my understanding is that adding points on the curve involves the geometric operation of drawing a line between two points and finding the third point that intersects the curve (with flip across x-axis). When it comes to doing things like combining public keys and public nonces, is the same geometric operation still occurring? Isn't this still described as 'adding' points on the curve?


texts: In order to perform a 51% attack someone has to concentrate huge amounts of computing power. Obviously this would be very expensive. But in return the attacker obtains the block reward and mining fees for every block mined during the attack window. Supposed mining is profitable, shouldn't this revenue compensate for the expenses?


texts: How many confirmations does bitpay wait?

texts:
I've made one purchase with bitpay, it has been received by the merchant who is stating "Payment received. Waiting for more confirmations". While this is fine, I find it quite odd I didn't manage to find exactly how many confirmations are they going to wait for.

Is it configured merchant-side, or is a constant for all bitpay transactions? If the latter, how many?

Really quite puzzled I didn't find anything about that in the bitpay site...


texts: After bitcoin-cli -regtest -sendtoaddress "address" That address's balance is always 0

texts:
I'm not quite sure what I'm doing wrong here. I believe I have followed everything correctly but for some reason its still not working? I am using directions from here: https://bitcoin.org/en/developer-examples

bitcoin-cli -regtest generate 101 < This prints that long list of new satoshis

bitcoin-cli -regtest getbalance

50.00000000
Ensuring that the balance is 50

bitcoin-cli -regtest getnewaddress < Make sure I have a new address to send satoshis to

bitcoin-cli -regtest sendtoaddress mviKj9i2zQmoLVUGkLBMuDhwvAwDmfrAmZ 10.00
Attempting to send satoshis. This returns the transaction ID.

bitcoin-cli -regtest generate 1 < Should confirm it

bitcoin-cli -regtest getbalance mviKj9i2zQmoLVUGkLBMuDhwvAwDmfrAmZ

I am expecting this to return 10.00 however it returns 0.00000000

Any ideas on how to fix this?


texts: Multibit: Using the same passphrase for both my wallet and exported private keys

texts:
I have a password-protected wallet in Multibit that I have backed up in multiple locations.

I have exported the private keys from this wallet. The private keys are password-protected using the same password as my wallet.

The password is more than 50 characters (passphrase) with words that cannot be found in a dictionary.

The wallet file and private keys file are stored together.

I don't care if the attacker can see my balance.

My questions:

How (un)safe is this?
If an attacker retrieves these files, can the attacker take a cryptographic shortcut because both files use the same password?


texts: Wallet validation methods (centralized, SPV, etc.) - please clarify for Ledger and in general

texts:
1) ledger: https://bitcoin.org/en/wallets/hardware/ledgernanos/

  Variable validation - Payment validation features are provided by the software wallet you use with this device.

2) wasabi: https://bitcoin.org/en/wallets/desktop/windows/wasabi/

  Centralized validation - This wallet relies on a centralized service by default. This means a third party must be trusted to not hide or simulate payments.

3)  Simplified validation (SPV) - This wallet uses SPV and random servers from a list.

Community, above linked definitions for wallet validation types is taken from the popular bitcoin website. I can understand every type, but the first one called "Variable validation" of Ledger.

Question: Is this technically correct to define Ledger's validation method like bitcoin.org defines it above?
If not, what is from your knowledge Ledger's validation method?

And If yes, I do not understand their definition. Can you explain from technical/censorship standpoint, what it means?  How is Ledger using servers for validation, is it their own servers or what is the difference to a centralized validation method?

Thanks


texts: I just lost 1.36275883 ($313), and I don't know how it happened or how to prevent it again

texts:
I just opened my multi bit wallet, and the  1.36275883 that was in there is now gone. It loaded a brand new wallet, so I don't even have my old wallet with the old transactions or password. I know what my old address was. I checked it on blockchain.info, and sure enough, there is the transaction that emptied it out.

So I can kind of make peace with losing over $300. I'm mad about it. But what I really need to know is, what happened and how do I prevent it from happening again. Can someone help with this issue?


texts: How to add a signature to a transaction which I can broadcast

texts:
I am using ledger and multi sig to sign a transaction I got signature hash where both party signed the transaction. How can I attached this signature to the transaction so that I can broadcast it to network?
any code reference will be welcome. Currently I am referencing electrum code.


texts: How to Connect already running bitcoind in AWS to Insight API in different AWS Server

texts:
Need to create a bitcoin explorer using bitcoind. I am using bitcore and insight API for this purpose.

Currently running bitcoind in AWS Server with all port open. Need to connect this running bitcoind with bitcore and use insight-api and UI in different server.

This my bitcore-node.json file:

    var configuration = {
 datadir: '/home/.bitcoin',
 network: 'testnet',
 services: [
   {
     name: 'bitcoind',
     module: Bitcoin,
     config: {
       spawn: {
         datadir: '/home/.bitcoin',
         exec: '/home/Downloads/bitcoin-0.16.1/bin/bitcoind'
       }
     }
   },
   {
       name: 'web',
       module: Web,
       config: {
           port: 4001
       }
   }
 ]
};

This is my bitcoin.conf

server=1
testnet=1
whitelist=127.0.0.1
txindex=1
addressindex=1
timestampindex=1
spentindex=1
zmqpubrawtx=tcp://127.0.0.1:28332
zmqpubhashblock=tcp://127.0.0.1:28332
rpcallowip=127.0.0.1
uacomment=bitcore

Need to Connect the Insight API to in the A server to Bitcoin in B server.


texts: What are some proposed solutions when Bitcoin block rewards drop below 1 BTC?

texts:
Many proponents state that Bitcoin will not work in the long term when block rewards drop below 1 BTC or even zero and have mining rely on just transaction fees. I never did the math calculations until now, but I can see what they mean when they say you can't rely on the fee market.

Reasoning is the following, when mining rewards reach ZERO:

Bitcoin current max transactions per second is: 7 tps
7 * 600 seconds (10 min) = 4200 transactions per block
If each transaction was worth:

.05 USD = .05 * 4200 transactions per block = $210 block reward

.50 USD = .5 * 4200 transactions per block = $2100 block reward

This is assuming block rewards are ZERO.

Now if leaving a mining machine on and it cost a significant amount of electricity. Many miners won't turn it on anymore, which leads to a much lower difficulty hash rate. From there any big player can come in with massive mining power and cause a 51% attack or even just stall the network by not accepting any transactions.

What are some of the proposed solutions to this supposedly problem in the long term?


texts:
I want to mine Bitcoin using the Bitcoin Core client.

I have followed the steps on https://www.youtube.com/watch?v=Xd4Opw0Upok, but when I type "setgenerate true" in the console, it replies with "Method not found (code -32601)"

How can I mine Bitcoin with Bitcoin Core?


texts: Multisig wallet issue - pair nodes (daemons) wallet.dat and pvt keys

texts:
Intro:
I am having an issue of accessing multisig wallet.
due to previous situation I have mixed up private keys and wallet.dat files
Multisig is 2 out of 3
Multisig works this way:
Synchronize multisig addresses between two running bitcoinds
Connects to both bitcoinds, figures out which one knows all the public keys for the mulitisig address, then tells the other about the address.
I have both seeds/sigs
First seed (sig) is a wallet.dat files (got 3 of those not sure which one I have to use)
Second seend (sig) are 6000 pvt keys (all mixed up)
Problem:
I want to pair first and second sig/seed - to pair wallet.dat on one daemon and pvt keys on other so it could generate access to a wallet where bitcoins are.
This would also generate public keys (3 of those) which will also gain me an access to wallet.
Has anyone had experience with this sort of issue?


texts:
I've read both the Nxt whitepaper and many other resources on the wiki but I still can't seem to understand how exactly the forging process works. From what I understand, there are a bunch of online users with their account "unlocked" (so they can sign the next block if they win). I don't understand how the winner (or the next forger) is decided. Is it random, or is it based on how many nxt coins one has?

For example let's imagine there are three users online with their accounts "unlocked": Alice (has 40 nxt), Bob (has 55 nxt) and Fred (has 13 nxt). The wiki says:

  Your probability of forging a block depends on your share of the total
  number of coins that are active on the network.

If that's true, wouldn't Bob (who has more coins than Alice and Fred) win the block generation every time? But then how is it possible that even accounts with little coins are still able to win at forging? Does it have something to do with the fact that the winning forger has to wait 1440 blocks before they can forge again? Is this what gives a "chance" to the less-rich users to win sometimes?

Also, if Bob is winning every time, couldn't he just go back the last 10 blocks or so and replace them with different blocks?


texts: How do Javascript-based wallets generate random numbers and is this cryptographically secure?

texts: Hybrid wallets and some paper wallet generators create private Bitcoin keys using Javascript inside the browser. Which source of entropy do they use? How do they make sure the PRNG is suitable for long-term security?


texts:
I'd like to install Nxt on Ubuntu (a private node). I am a beginner and have no clue about how to do that. Is there anyone out there that could give me some directions/advices ?

Any help would be wonderful.

Thank you


texts:
I have just installed an Electrum wallet on my Ubuntu machine, and transferred some funds into it.  I wish to back up the wallet, so if my computer is dead or stolen, say, I will be able to install Electrum again and restore the wallet.

(In fact, it would be best to be able to restore the wallet from other software, not necessarily Electrum, if that's possible).

My wallet has a name (btc1) and a password. After opening it, in the wallet menu, I have the seed option grayed out. I am able to export private keys, however. If I understand correctly, the wallet itself is located in the file ~/.electrum/wallets/btc1. If I copy that file, say, to a different machine - then the wallet is also there?

I'm a bit confused about all of that.


texts:
I am trying to generated the checksum for the mnemonics (BIP39) but can't get the correct value.

I used 3 resources

This explains the mnemonic generation https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki#Generating_the_mnemonic
This contains test vectors
https://github.com/trezor/python-mnemonic/blob/master/vectors.json
This is the word list
https://github.com/bitcoin/bips/blob/master/bip-0039/english.txt

I can't get the first test vector to work out.

I SHA256 0x00000000000000000000000000000000 into 374708fff7719dd5979ec875d56cd2286f6d3cf7ec317a3b25632aab28ec37bb

The first four bits, which are the checksum bits, are 0b1101

That makes the last 11 bits of seed + checksum 0b00000001101, the last word of the mnemonic. Corresponds to 13 or index 12 "accident". However in the test vector it's index 4 "about".

I get the wrong word for every test vector. Probably a silly mistake. Thanks.


texts: Confused About Hash In Satoshi Nakamoto Diagram

texts:
In Satoshi Nakamoto's diagram:

Consider the Hash block in the first transaction block above:

How is that Hash value calculated? I see arrows from an Owner's Public Key and another arrow, so it's confusing. Is the arrow coming from the Owner's Public Key saying that the Hash is encrypted with the owner's public key? If yes, then what is the other arrow? Is that involved during the encryption with the public key? In other words, does the previous transaction's hash get somehow combined with a new hash before being encrypted with the public key? What exactly is going on here?

Thank you.


texts: How can someone mine bitcoins at billions or trillions of hashes per second when the nonce is only 2^32 in size?

texts:
According to another similar question on Bitcoin Stack Exchange, https://en.bitcoin.it/wiki/Block_hashing_algorithm shows how the mining algorithm works for Bitcoin.  The problem is, it shows the nonce as being not larger than 2^32.  When someone has gone through all the values the nonce can have, it seems the time changes and the search for a proper nonce begins anew, as even changing the second by 1 is enough to warrant testing the nonces again in the hashing algorithm.

As it relates to the actual mining algorithm/software, with all this in mind, how can mining hardware provide billions or trillions of hashes per second when each second only provides ~4.3 billion different nonces and requires a new "second of time" to change the time so as to begin anew with the nonces?  It seems as though in the most extreme circumstances, even having the "merkle root" changing due to the addition of a transaction to the block would not occur frequently enough for the most powerful ASICs to always have work to do.

To the extent that it is possible I am seeking a potentially elaborate yet easy to understand answer.


texts: Altcoin: Send/receive transactions between nodes have high failure rate

texts:
I've noticed that an unusually high number of my attempted send transactions between my nodes (which is currently only 6 at most, but never less than 4) will not broadcast regardless of the amount of time I wait. I end up having to eventually abandon them to return the funds from the wallet I am trying to send them from. I have noticed no specific correlation between sender and recipient  (like a single node always being unable to send or receive) and have noticed that every successful transaction is broadcast and appears in the memory pool pretty much immediately after sending.

Is there any specific cause for this? Maybe the fact that I'm currently limited to such a small # of nodes?

Have used getnewaddress to generate every address that has successfully and unsuccessfully received coins so I find it difficult to believe the actual addresses can be the problem as they should all have been derived from valid keys.

Schwifty


texts: Which notable Bitcoin-related sites offer referral rewards?

texts: TradeHill used to offer a referral bonus when you got other people to sign up with your link, and there are a couple other sites that offer similar rewards for referrals. Which notable Bitcoin-related websites offer such rewards?


texts: which cloud backup files do I need to keep

texts: I just installed Multibit HD, did a few transactions, and I already have 15 .zip.aes backup files?  Do I have to keep all of these forever, or only the most recent one?


texts: Where can I find market volume data with greater resolution than 24hr periods?

texts: I have scraper that pulls data from coinmarketcap for all coins for all historic periods (down to 15min intervals) however, the only volume info available is 24hr volume. Does anyone know if it's possible to get 15m/1hr volume data (historic) from coinmarketcap? Failing that, any reasonable approach for converting the 24hr data to 1hr/15m? It would only be a rough estimate, I know. I don't know why they don't provide hourly volume data as well.


texts: What is the difference between the txsize in mempool and mempool dynamic usage?

texts:
There is a table for the txsize in mempool and dynamic memory usage of mempool on statoshi.info's mempool overview?
The default size of mempool defined in Bitcoin is 300MB, so is this default size the total txsize or the dynamic memory usage?


texts: Best practices for service/merchant handling bitcoins

texts:
Possible Duplicate:
  Best way to safely host a high volume online transactional wallet?

There have been numerous incidents where bitcoin services have been hacked and large amounts of bitcoins have been stolen. There was even an exchange that accidentally deleted its only copy of its bitcoin wallet.

Which best practices should a service or merchant follow when handling bitcoins?


texts: How to fetch all UTXO from a SPV wallet using bitcoin-filter.js (or other lib)?

texts:
I am using bitcoinjs-lib to create private key (WIF), addresses and sign the transactions.

I would like to fetch all transactions (UTXOs) associated with a wallet. I found these libs:  bitcoin-filter  and bitcoin-net .

But I didn't understand the code below:

var filter = new Filter(peers)
filter.add(new Buffer('818895f3dc2c178629d3d2d8fa3ec4a3f8179821', 'hex'))
filter.add(walletObject)

What parameters does filter receive ? Are they the addresses ?
If so, how can I find all the used addresses of a HD wallet ?


texts: Can you delete / remove / update a decentralized asset in the NXT Asset Exchange?

texts:
I made a mistake when creating a nxt asset on the asset exchange. How do I delete it or just update the description?

If I can't do neither, how do I get it delisted if its even possible.


texts:
As I understand, when Bitcoins are created the beneficiary's Bitcoin address is made public. Likewise, when Bitcoins are transfered, both the source and destination Bitcoin addresses are made public.

From the above, it seems that the balance of every Bitcoin address can theoretically be inferred from the public logs. Is this true? Moreover, are there lists of all Bitcoin addresses with a non-zero balance, together with the associated balances?


texts: Lightning Network: can I create a channel from a preexisting channel?

texts: If I open a channel with myself for 0.01 BTC, with one end having all, and the other having none, could I create an updated contract, or state, to send 0.001 BTC to an address owned by Alice, even though this address would not be in the blockchain, whereby she now has a valid channel with 0.001 BTC, and I have 0.009?


texts: What is fTestnetToBeDeprecatedFieldRPC seen in chainparams.cpp?

texts: fTestnetToBeDeprecatedFieldRPC is a bool type variable set to some values in the main, testnet and regtestin chainparams.cpp. What is the use of this value ?


texts: Ripple's gateways are only opened to financial institutions like banks and credit card processing companies or anyone who is willing to invest into Ripple's infrastructure ?


texts: Bitcoin Testnet Trouble with bitcoin-ruby

texts:
I am having trouble with the bitcoin-ruby gem. I get the following error when trying to send money to another address I have on the test network:

  /var/lib/gems/2.2.0/gems/bitcoin-ruby-0.0.7/lib/bitcoin/protocol/txout.rb:76:in
  pk_script=': undefined methodbytesize' for nil:NilClass
  (NoMethodError)

I am generating a private key with:

def new_address
 Bitcoin::generate_address
end

And getting details for the private key with:

def key_details(prikey, pubkey)
  #returns prikey, prikey_hash58, pubkey_hash58, pubkey_uncompressed, address as a hash
  my_key = Bitcoin::Key.new(prikey, pubkey)
  { prikey:prikey,
    prikey_base58:my_key.to_base58,
    pubkey_58:my_key.hash160,
    pubkey: my_key.pub_uncompressed,
    address:my_key.addr
  }
end

The code I have to send money to myself is as follows:

require 'bitcoin'
require_relative 'utilities.rb'
require 'open-uri'

Bitcoin.network = :testnet3

def build_transaction(prev_tx, prev_out_index, key, value, addr, message)
  include Bitcoin::Builder

  new_tx = build_tx do |t|
    t.input do |i|
      i.prev_out prev_tx
      i.prev_out_index prev_out_index
      i.signature_key key
    end
    t.output do |o|
      o.value value
      o.script {|s| s.type :address; s.recipient addr }
    end
  end
end

def prev_tx(prev_hash, network)
  if network == "testnet3"
    prev_tx = Bitcoin::P::Tx.from_json(open("http://test.webbtc.com/tx/#{prev_hash}.json"))
  else
    prev_tx = Bitcoin::P::Tx.from_json(open("http://webbtc.com/tx/#{prev_hash}.json"))
  end
end

def key(publ_key, priv_key)
  key = Bitcoin::Key.new(priv_key, publ_key)
end

def bin_to_hex(s)
  s.unpack('H*').first
end

#transaction inputs
priv_key = "private_key"
publ_key = "public_key_long_format"
address = "address"
previous_tx = "previous_tx_hash"

# generate tx info off inputs
key = Bitcoin::Key.new(priv_key, publ_key)
prev_tx = prev_tx(previous_tx, "testnet3")
prev_out_index = 1
tx_value = prev_tx.outputs[prev_out_index].value

# build new tx
tx = build_transaction(prev_tx, prev_out_index, key, tx_value, address, "hello")

#
# puts tx.to_json
puts bin_to_hex(tx.to_payload)


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

texts:
Are there any online or open source (i.e., free, or at least cheap) accounting systems that do multi-currency so that I can record revenues and payments made using BTCs in the same system that I use for USDs?

If not, are there any suggestions for how best to do this?


texts: gcminer with ATIRADEON HD3600 on ubuntu 12.04 64bit headless won't detect GPU

texts:
I am following this guide: http://rdmsnippets.com/2013/03/20/bitcoin-mining-with-ubuntu-12-04-tls-and-cgminer/

But it won't work on my server (Specification's are in the Subject-field)

I get this error:

koen@gorgabal-Server:~/bitcoinmining$ ./cgminer/cgminer -n
 [2013-06-23 15:03:51] CL Platform 0 vendor: Advanced Micro Devices, Inc.
 [2013-06-23 15:03:51] CL Platform 0 name: AMD Accelerated Parallel Processing
 [2013-06-23 15:03:51] CL Platform 0 version: OpenCL 1.2 AMD-APP (1113.2)
 [2013-06-23 15:03:51] Error -1: Getting Device IDs (num)
 [2013-06-23 15:03:51] clDevicesNum returned error, no GPUs usable
 [2013-06-23 15:03:51] 0 GPU devices max detected
koen@gorgabal-Server:~/bitcoinmining$ sudo aticonfig --lsa
* 0. 01:00.0 ATI Radeon HD 3600 Series

* - Default adapter

I can't switch to windows because of several reasons, does anybody have an idea of what I am doing wrong?

Thanks in advance!
ps: I have used linux for several years now, so I know my way around. This is a fresh server installation.


texts: How many txid gets added to mempool per second?

texts:
I am trying to get the txid using json/rpc and trying to find out how many tx_id gets added to memory pool ?

i think it comes down to how many bitcoin transaction are possible per second ?

is there any fixed number ? or maximum number ?


texts: API: keeping account balance positive (+knowing in advance the transaction fee)

texts:
I'm using the json API. I need to keep all the account balances positive: I call getbalance first, check if it has enough bitcoins to proceed, and then move or sendfrom.

This approach causes two problems.

Problem 1 is that this is not an atomic operation, so after the first getbalance the balance could actually be changed.

Problem 2 only happens with sendfrom: there might be a transaction fee, hence if the user sends his entire balance, he'll have a negative balance due to that.

Solution to Problem 2 would be to know in advance the transaction fee: I noticed (though I didn't try) I can set it with settxfee, but I found no call to get it, is there?

While I could implement some external lock mechanism to solve Problem 1, I'd rather use a bitcoind native method, though I get it does not exist, does it? Hacking the sendfrom function to have it check the balance before sending would be enough, I guess?


texts: How to share your wallet key/seed in case you are hit by a bus

texts:
This very useful answer says:

Share overlapping parts of your private-key or seed phrase with several family members with instructions on what to do if you are hit by a bus this afternoon.

This sounds like very good advice, but the details of doing so seem like a complicated balance of trust and chance of dying.  For example, I may trust my spouse most, but they are likely to be in the same car as me.  My parents next, but they are old and frequently in the same car driven by an old person.  My siblings next, but there are not many of them.  My friends somewhat, but there are lots of them and they do not all talk to one another.
Has anyone devised an algorithm to split up your private key or seed such that you can balance these considerations?  Perhaps something like allowing you to specify that any one of these sets of people are sufficient to access funds:

spouse and one sibling
both parents and one sibling
All siblings
7 out of 15 friends


texts: generating a zprv from a base58 rootKey with bitcoinjs-lib

texts:
var bitcoin = require('bitcoinjs-lib');
let bip32 = require('bip32');

let rootKey = 'xprv9s21ZrQH143K32CfqoCQHtbKiEb5BqFazXX6jCtNCnuty3gUjxS4CsXWi9rcNyHdjDVPiC6P1bnyEZr2ioouRq56h6HAdwejeTty1BsSEtL'
const node = bip32.fromBase58(rootKey, bitcoin.networks.bitcoin);

//legacy account extended private key
console.log("LEGACY: " + node.derivePath("m/44'/0'/0").toBase58())
//xprv9y7nL2k2diLdA9bmop94K8Pec2WdL998PLdvTraxj5jiQ36gnLmhVJG4bY8FzgqZPaBM5HDBi9sgRK1ZCi14n5j4Pk1o6d3j4Y6T9NS4nA6
(works as expected)

//segwit account extended private key
//trying to get a segwit extended private key (zprv) using the same inputs as above.

I want to get a segwit/bech32 extended private key using the same root key as above. How can I do this using bitcoinjs-lib? BIP84 only works for mnemonics IIRC.


texts:
Considering how large the total blockchain is relative to average download speeds, why were the blocks never data compressed before being sent?

Why could this not be implemented on a new alt?


texts: What mathematical property links the Armory chain to the public/private keys?

texts:
According to the Armory site the Public Keys needed for the Bitcoin addresses can be generated without having access to the Private Keys, which ideally are stored on a completely different computer.

What mathematical property allows public keys to be generated without having the matching private keys? I take it they are seeded by the chain code somehow, so the chain code is the stored in the watch only copy of the wallet, while the chain code + root key make up the private wallet, right?


texts: How to recover coins from a wallet that uses BIP32 Deterministic Keys?

texts: Say I am using an online wallet that uses BIP32 deterministic keys and the site goes down. I have a backup of my seed (passphrase). Is there a github repo that I can download, run on an offline computer, present it with my seed, present it with the BIP32 Path: m/44'/0'/0'/0/2 and recover the private key associated with that seed/path so that I can transfer the funds out of it?


texts: Can I get all block header data like the SPV node?

texts:
It hasn't been long since I studied Blockchain.
I only need header data, not all block data, for study purposes.
As far as I know, the SPV node stores only the block's header information.
Can i get all block header data in python?


texts: Can I use Electrum on my everyday computer?

texts: Or do I have to use a computer that has never used the internet?


texts: Blockchain.info wallet payload strange format

texts:
Our situation:
Blockchain.info wallet Password lost/broken after update.

Account(wallet) was created in September 2016 in mobile app on iPhone

We use 2FA

We have:

BCI account (wallet) ID
Working e-mail and connected phone number
Password, we sure (only digits)…
Remember of the wallet addresses
+Now we have some payload from response of server on login attemp

Have NOT:

We haven’t save any Seed recovery phrase and private keys

We make all operations with mobile app, but after on of the iOS (or application) update in April of 2017 BCI application was reset or something else wrong with saved password..
We trying to login and get «error wallet decryption» phone/desktop

While I was trying to log in with desktop, confirm by e-mail and phone, I’v got some part of response with such a payload

{\"pbkdf2_iterations\":5000,\"version\":3,\"payload\":\"AAAAAAAAAAAAAAAAAAAAA(here is numbers and digits)\»}»
          }

It’s very strange payload starting with AAAAAAAAAAAAAAAAAAAAA…

Trying btcrecovery util, but no result (use this response part as wallet.json and some password tokens).
(python btcrecover.py --wallet pl.json --tokenlist pass.txt)

May be our password was reconverted some way during the BCI updates, iOS app updates?

May be need change iterations count?

May be old version was initially and 5000 liter v3 is wrong?

What version of the My Wallet was in the beginning of 2016? V2 or V3?

What iterations 5000 or 10000?

Probably, we can try to brute force seed someway as we have one of the wallet addresses?

Experts, please, help us!
Probably @ChristopherGurnee can give us some tip?


texts: >50% crash induced by stakeholders of current financial systems

texts:
This is a though I had a few days ago.

There are stakeholders of our current financial systems who would like to secure their wealth. If these stakeholders sense bitcoin as a threat to their wealth, they would want to stop it. In this case they would want to stop it with a >50% attack.

I have read the Bitcoin Papers and found the following:

  The incentive may help encourage nodes to stay honest. If a greedy attacker is able to
  assemble more CPU power than all the honest nodes, he would have to choose between using it
  to defraud people by stealing back his payments, or using it to generate new coins. He ought to
  find it more profitable to play by the rules, such rules that favour him with more new coins than
  everyone else combined, than to undermine the system and the validity of his own wealth.

Since the current financial systems won't get undermined, a >50% attack still makes sense from their point of view.

How big are the efforts to induce a >51% attack? (DDoS / hack Pools + provide own hashing power)
Could the crashed BlockChain get recovered? (after implementing attack prevention code)


texts: Can unupgraded nodes that accept zero confirmation be fooled after SegWit?

texts:
Considering the following scenario:

  After deployment of SegWit, there remain two old clients (with software that is unaware of SegWit) A & B.
  A funds a transaction to pay B using a SegWit output which appears to both as ANYONE_CAN_SPEND.
  Upgraded nodes ignore this transaction, as it obviously isn't signed correctly under the rules of SegWit. (Perhaps even ban old nodes that relay this "invalid transaction" to them?) However, among old nodes the transaction gets propagated as valid.

In the case that B gets notice of the transaction, would it display an "incoming unconfirmed transaction"?
Could people get fooled that way if they accept Zero Confirmation (which I'm aware isn't safe)?


texts: Why is the longest block the one that gets accepted by all the nodes?

texts: I'm confused about one of the core principles of Bitcoin.  When various nodes are confirming transactions, why does the longest block win out?  That is, why doesn't the system allow whoever confirms a transaction or group of transactions first be the block that all the other nodes accept?  I realize there has to be some logic in the situation where two nodes submit confirmations at the same time, but what problems would get introduced if the node that confirmed a group of transactions first, regardless of the size of the block, win?


texts: why is bitcoind daemon occasionally stuck at `Opening LevelDB in .../.bitcoin/chainstate`despite clean shutdown

texts:
My bitcoind daemon sometimes takes an hour to go past Opening LevelDB in .../.bitcoin/chainstate

After googling a bit, i thought it was simply an unclean daemon stop causing a leveldb corruption. But then this happened again this week despite having been stopped correctly (as indicated by Shutdown: done log entries). I was using systemctl stop, not bitcoin-cli stop if that makes any difference.

$ journalctl -u snap.bitcoind.daemon --since "1 week ago" | grep -B1 -E "Opened LevelDB successfully|Shutdown: done"
...
Nov 12 02:09:34 localhost bitcoind.daemon[13878]: 2019-11-12T07:09:34Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/blocks/index
Nov 12 02:09:34 localhost bitcoind.daemon[13878]: 2019-11-12T07:09:34Z Opened LevelDB successfully
--
Nov 12 02:09:39 localhost bitcoind.daemon[13878]: 2019-11-12T07:09:39Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/chainstate
Nov 12 02:09:39 localhost bitcoind.daemon[13878]: 2019-11-12T07:09:39Z Opened LevelDB successfully
--
Nov 12 02:28:16 localhost bitcoind.daemon[13878]: 2019-11-12T07:28:16Z scheduler thread interrupt
Nov 12 02:28:17 localhost bitcoind.daemon[13878]: 2019-11-12T07:28:17Z Shutdown: done
--
Nov 12 02:28:18 localhost bitcoind.daemon[14353]: 2019-11-12T07:28:18Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/blocks/index
Nov 12 02:28:18 localhost bitcoind.daemon[14353]: 2019-11-12T07:28:18Z Opened LevelDB successfully
--
Nov 12 02:28:25 localhost bitcoind.daemon[14353]: 2019-11-12T07:28:25Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/chainstate
Nov 12 02:28:25 localhost bitcoind.daemon[14353]: 2019-11-12T07:28:25Z Opened LevelDB successfully
--
Nov 12 06:57:36 localhost bitcoind.daemon[14353]: 2019-11-12T11:57:36Z scheduler thread interrupt
Nov 12 06:57:37 localhost bitcoind.daemon[14353]: 2019-11-12T11:57:37Z Shutdown: done
--
Nov 12 06:57:39 localhost bitcoind.daemon[18691]: 2019-11-12T11:57:39Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/blocks/index
Nov 12 06:57:39 localhost bitcoind.daemon[18691]: 2019-11-12T11:57:39Z Opened LevelDB successfully
--
Nov 12 06:57:51 localhost bitcoind.daemon[18691]: 2019-11-12T11:57:51Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/chainstate
Nov 12 06:57:52 localhost bitcoind.daemon[18691]: 2019-11-12T11:57:52Z Opened LevelDB successfully
--
Nov 17 13:27:36 localhost bitcoind.daemon[18691]: 2019-11-17T18:27:36Z scheduler thread interrupt
Nov 17 13:27:38 localhost bitcoind.daemon[18691]: 2019-11-17T18:27:38Z Shutdown: done
--
Nov 17 13:31:00 localhost bitcoind.daemon[18236]: 2019-11-17T18:31:00Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/blocks/index
Nov 17 13:31:00 localhost bitcoind.daemon[18236]: 2019-11-17T18:31:00Z Opened LevelDB successfully
--
Nov 17 13:31:11 localhost bitcoind.daemon[18236]: 2019-11-17T18:31:11Z Opening LevelDB in /root/snap/bitcoind/common/.bitcoin/chainstate
Nov 17 14:32:53 localhost bitcoind.daemon[18236]: 2019-11-17T19:32:53Z Opened LevelDB successfully

This delay coincides with a spike in memory usage that i only experience in this situation. Otherwise, the daemon runs happily with 512M RAM and no swapping, albeit slowly of course.

# swapon --show=NAME,USED,PRIO
NAME        USED PRIO
/dev/vda2 511.2M    1
/dev/dm-2 441.4M   -2

It is not a tragic situation since the daemon eventually starts. But I'd like to understand whether this is happening because of something I'm doing wrong. I'm happy to enable debug logs to provide more info if needed.


texts: What makes the block time of a certain coin shorter than the other?

texts: What are the factors that impact the block time of a certain coin? Is a shorter block time always better or there's a trade off?


texts:
I've just setup GUIMiner, I have two graphics cards, and they are both running. However, one is getting ~400 Mhash/s, the other is getting ~10 Mhash/s.
The monitoring of the GPU's also shows one running at 95%, the other at ~5%.

Is there an obvious reason for this?


texts: How can the blockchain keep only one version of the ledger equal across all nodes

texts:
Lets say miner A is working on block X, while miner B works on block Y.
Both miner A and B find the hash for their blocks almost at the same time, and as such, they start broadcasting their results to other miners, so a consensus can be reached.

Are all the miners on the network needed to reach such consensus?

If such, what happens if a group of miners is working to reach a consensus on a block, and some other group is working on some other block (given that the broadcast to every node takes a little bit of time)?

How do they decide what block gets added first to the blockchain?

Note that I'm pretty new to this, and still trying to learn how the blockchain works.


texts: Naming Convention In Bitcoin Source Code

texts:
Is there specific reference for naming conventions in Bitcoin Core source code?
I see regularity in class naming with prefix "C" (Chain, CInv etc.) or pointer naming with "p" (pprev, pnode etc. ) and am wondering if there's more to my list of prefixes or other conventions.

Is there a Bitcoin-specific naming convention at all?


texts: What else can bitcoin inventory vectors be used for?

texts:
As described in the protocol specification bitcoin nodes respond to the inv command, which queries a node's knowledge of one or more objects, with an inventory vector. According to the bitcoin wiki, inventory vectors can either be of type transaction or type block. What else could be stored in a bitcoin inventory vector?
https://en.bitcoin.it/wiki/Protocol_specification#Inventory_Vectors


texts: is transaction malleability a threat to my local wallet?

texts: I have a local Bitcoin-QT wallet. Can transaction malleability be used to steal my horde of tens of thousands of Satoshis?


texts: What is the network mempools unconfirmed transaction expiration time?

texts:
I sent a bare $1000 multisig transaction using sendrawtransaction with a too low fee.
When I create a new transaction with a higher fee, I m getting txn-mempool-conflict error, and when I use the bumpfee command, I m getting Transaction is not BIP 125 replaceable.
So given I sent it yesterday, in how much time I would be to access the money again?


texts: Does anyone have an idea of where can I find a copy of the bitcoin source code. I mean doesn't it supposed to be open source, where is the open source project for bitcoin so I can read the code.


texts:
I accidentally sent Bitcoin Cash from my Coinbase wallet to my wallet at Vaultoro. The problem is it didn't show up because Vaultoro only takes Bitcoin.

Can anyone give me a step by step on how to retrieve this? I tried to get Vaultoro to help but they didn't seem to care.

Please help.


texts:
I've been interested in Bitcoin for a while. I've been thinking I'd like to give it a go and see if I can make my own cryptocurrency, just to see if I can.

I run my own small web hosting company, the main reason why I don't want to accept Bitcoin is its price volatility. I mean, at one point it was worth $1000 and now its worth $315.

I was wondering, from purely an economics standpoint, would a currency in which all payments, transactions etc ... where decentralised work if one key part was centralised.

I'd like to make all clients download a text file once a week. In the text file would a number, and that number would tell all of the transaction verifiers how many new currency units can be created in any 24 hour period.

I would like to use this file to control the rate at which new currency units are created, there would be no overall limit like Bitcoins 21M. The value would be controlled by controlling the number of currency units that can be created in any 24 hour period.

So since I know nothing about economics I was wondering, would this work?


texts: Receiving payment in Lightning Network is a big problem?

texts:
There are some requirements to receive Lightning funds. According to here,

  Nothing can be received immediately after creating a new payment channel, as ‘room’ for incoming funds has to be made by spending some funds first.

I would like to be able to receive LN payment on online shop. In order to do this and in my understanding, I have to either

wait until my customers fund channels to me, or
find a node that already has many channels and get it connect to me with an ample amount of cap.

The former way does not make sense because users have to open another channel to my node if they've already opened one. The latter way might work if a big cap node thinks my business would be great and users would come along. Receiving in LN is very difficult and a big problem for merchants. Thoughts on it? Or if my thought above is wrong, please educate me.


texts: I have a wallet with 100 addresses in MultiBit. From what I've gathered, bitcoins are linked to a specific address. Is there a way to see in MultiBit how much of my balance belongs to each address?


texts: How Cross border Crypto remittance apps work?

texts: I want to develop an app that allows people to send money cross border using crypto currencies, I am trying to understand the services my app will need to achieve such? Interms of  for example, how do the two individuals involved in the cross border remittance buy and send crpyto and how it's converted to local currency? Is this achievable and effective to reduce current charges of cross border payments, I have been doing some research for some time and would love to be lead in the right direction, thanks


texts: BFGMiner + CGMiner solo mining, how to specify payout address

texts:
I am currently trying my luck at solo mining a few types of crypto-currencies. My question is why does BFGMiner require a --coinbase-addr- argument for solo mining to know where to payout rewards to and CGMiner does not?

I am because today I found a block with BFGMiner in Terracoin mining and it seemed to not have payed me even though I specified a coinbase address. I want to make sure that if I am so lucky to find a block again that I actually get paid.

https://bitcointalk.org/index.php?topic=309486.new#new


texts: Bitcoin library - how to check number of confirmations

texts:
when I use bx fetch-balance I get this output:

  $ bx fetch-balance 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa

  balance {
      address 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa
      confirmed 1538241483
      received 6538241483
      unspent 6538241483 }

it doesn't show the number of confirmations.

how can I check the number of confirmations using bx command?


texts:
I'm conscious that Bitcoin's script is not turing complete, as multiple answers point out (e.g., this answer and this one). But I'm wondering if script can express the language of a PDA or equivalently, of a context-free-grammar.

I think it should be so, because of script's stack, but I'm not sure and therefore I ask for some clarifications/confirmations.


texts:
How can I get this value, as I understand this complexity

https://github.com/bitcoin/bitcoin/blob/master/src/test/pow_tests.cpp#L55

0x1c0168fd


texts: Does the node count reflect the mining power support of different Bitcoin versions?

texts:
In the current Bitcoin blocksize debate, xtnodes.com shows a pie chart of nodes running different implementations of Bitcoin; Classic, XT and Unlimited, etc.

Does this node count in any way reflect the mining power behind each Bitcoin version?


texts: transferring Bitcoins between two exchange

texts:
I transferred my bitcoins from Binance to Yobit. The BTC are gone from Binance but it is not coming on Yobit.net.
I also transferred Litecoin from GDAX to yobit. They are also not showing in Yobit. What should I do?


texts: I sent BCH to a segwit btc address, how can i get it back?

texts:
I accidentally sent bitcoin cash  to a segwit bitcoin address, please can anyone help me on how i can get it back. i tried using this recovery service, https://bch.btc.com/docs/help/bch_segwit_recovery
but they never replied me or responded to my email, please what can i do?


texts: I don't know whether the graph is wrong, or I'm interpreting it wrong, but it appears to say that if I had converted a dollar ten years ago (I didn't), I would have received 20.0 XBT, and if I didn't lose it, I could today convert it to more than twenty thousand dollars.  Seems hard to believe.  Is it actually true?  The answer will not benefit me financially, but I'm extremely curious.  :-)


texts: Bitcoin sent to a defunct address - what happens to it?

texts:
I got the address for my account on a site and wrote it down. As I had had a huge hassle buying my bitcoin that morning due to problems with the vendor's site (and which they denied was at their end for 3 or more hours, nearly drove me spare) I was flusterred quite badly.

Anyway, for some reason that is still not apparent to me I clicked on a button saying "generate new account". However, as the site kicked me out due to poor connectivity and it flagged me that "your request could not be processed", I sent the bitcoin off to the address I had written down.

Some hours later I went to the site to check my balance...my funds were not there. There was A NEW ADDRESS for sending bitcoin to in my account details.

So, it would appear that I have sent my bitcoin to a valid address that is now redundant.

What will happen to my bitcoins? Will they bounce around for a few days before coming back or will they just disappear into the ether?