texts: Slushpool Miner Hashrate always Lower than Local Hashrate

texts:
A Short Story

There is an Antminer server farm I provide support for with over 100 BC servers—mainly S9 and T9 models. There are three specific S9 miners that are side by side right next to each other on the rack which continually show lower than normal hash rate in Slushpool.

When I check these servers in Slushpool they all three fluctuate often ranging from 11-13 TH/s but the web interface and command line RT and AVG hash rates are always normal with no fluctuation. Every time I check Slushpool though, it's almost always lower than normal and I've checked up to nearly a hundred times in one day just to ensure I was being thorough.

Question

Is there anything common or something someone else determined that could cause a miner hash rate to always show lower in Slushpool than what it shows from the local server?

  Notes

  I've checked both command line and web interface on all these and see the same thing; normal realtime and normal average always
  every time I check but with Slushpool, it almost always shows it is
  hashing lower by 1 or 2 TH/s.
  Typically when other miners in this farm have a lower than normal Slushpool  hash rate, the local servers have a value that correlates much closer to that hash rate so I'm
  trying to understand if there's something I don't understand here
  which may explain this.


texts: When do I get paid when mining with eligius?

texts:
So, i'm trying out mining with a mac and i'm not asking whether mining is possible, my question is is it actually even possible to make a minimal amount of bitcoins. I hear people saying that mining with bitcoin has now become "competitive" and I wonder if that means if we are fighting over who completes a block? I'm using eligius because they are one of the few pools that let people mine with gpu. When will I get paid? Do I need to keep mining for a few hours? Any help will be appreciated. thx. BTW: here is a my console log, is this correct?

[2017-05-24 13:58:39] API running in IP access mode on port 4052

 [2017-05-24 13:58:39] API running in IP access mode on port 4052
 [2017-05-24 13:58:39] Selecting poclbm kernel
 [2017-05-24 13:58:39] Error -30: Clearing output buffer for goffset test kernel (clEnqueueWriteBuffer)

 [2017-05-24 13:58:39] Error -30: Clearing output buffer for goffset test kernel (clEnqueueWriteBuffer)
 [2017-05-24 13:58:39] Initialising kernel poclbm.cl without bitalign, 1 vectors and worksize 256

20s:15.38 avg:39.71 u: 0.00 Mh/s | A:0 R:0+0(none) HW:0/none
20s:24.76 avg:39.65 u: 0.00 Mh/s | A:0 R:0+0(none) HW:0/none
20s:29.70 avg:38.93 u: 0.00 Mh/s | A:0 R:0+0(none) HW:0/none
20s:33.60 avg:39.14 u: 0.00 Mh/s | A:0 R:0+0(none) HW:0/none
20s:35.92 avg:39.23 u: 0.00 Mh/s | A:0 R:0+0(none) HW:0/none
 [2017-05-24 14:00:29] New best share: 2
20s:36.92 avg:39.11 u:71.49 Mh/s | A:0 R:0+0(none) HW:0/none
20s:38.17 avg:39.26 u:91.92 Mh/s | A:0 R:0+0(none) HW:0/none
20s:38.54 avg:39.24 u:80.43 Mh/s | A:0 R:0+0(none) HW:0/none
20s:39.22 avg:39.36 u:71.49 Mh/s | A:0 R:0+0(none) HW:0/none
20s:39.15 avg:39.32 u:64.34 Mh/s | A:0 R:0+0(none) HW:0/none
20s:39.01 avg:39.28 u:58.49 Mh/s | A:0 R:0+0(none) HW:0/none
 [2017-05-24 14:02:33] New best share: 2
20s:39.55 avg:39.37 u:71.49 Mh/s | A:0 R:0+0(none) HW:0/none
20s:39.51 avg:39.38 u:82.48 Mh/s | A:0 R:0+0(none) HW:0/none
20s:38.38 avg:39.18 u:76.60 Mh/s | A:0 R:0+0(none) HW:0/none
20s:35.81 avg:38.68 u:71.49 Mh/s | A:0 R:0+0(none) HW:0/none
20s:36.02 avg:38.54 u:67.02 Mh/s | A:0 R:0+0(none) HW:0/none
20s:36.92 avg:38.53 u:63.08 Mh/s | A:0 R:0+0(none) HW:0/none
20s:37.48 avg:38.52 u:59.57 Mh/s | A:0 R:0+0(none) HW:0/none


texts: Why would Bitcoin Core freeze my computer when syncing? And is it supposed to take this long?

texts:
24 hours ago, I finally bit the bullet and dug up my old computer, set it up physically, installed Linux Mint (with full disk encryption), installed Bitcoin Core through its software manager, started it, immediately selected "pruned mode" in the settings (kept it at default 2 GB since I have no idea if it's good or bad to increase/decrease it), closed it and started it again, to let it sync from scratch to 100%...
When I went to bed, it seemed awfully unresponsive, with mouse movements taking several seconds before they showed up on the screen.
When I woke up just now and looked at the progress, it was still at 21%, with "10 weeks left". It now would not at all react to any attempts to close it or click on anything. I had to "hard-cut" the power to the machine and restart it. Now I'm again running Bitcoin Core and so far, it seems very responsive and says "10 days".
It's connected directly to 100/100 Mb/s fiber, and the hardware is 3 GB RAM and a 2011-era Dell CPU. Dual core something. The HDD is 250 GB and mechanical. (Which is why it was not a choice to store the entire blockchain and I had to use pruned mode right away.)
I don't know what to make of this. My guess is that it was not actually doing any work during the entire night, instead having somehow "hung". I sure hope it's not some hardware issue or something, because that machine is the only practical means for me to have a decent chance of setting up a secure new wallet for cold storage.
Others online seem to be talking about "hours" to sync, but this seems like it at best will take at least four days, if everything goes perfectly and progresses exactly like it has so far, minus the hanging. And again, the program itself is talking about "10 days"... nope. Now it says "6 days". I just looked over at the screen.
Basically, I have no idea what's going on.


texts: Creating a multisig wallet with bcoin and receiving transactions

texts:
I am trying to create a multisig wallet from two externally generated xpubs. The process I am taking is to create two multisig wallets with the two xpubs, add each others keys as shared keys and generating the multisigscript using keyrings. However, when I send testnet coins to the base58addr that I generate in the end, I do not see it coming to either of my wallets. Could someone kindly help me figure out where I am doing wrong? This is my code:

const wallet1_accountKey = "tpubDCe8iQEHFMvcm9WZsYZEd8h9dNvoDidS3y9EVkDzZZr59NcNF2n8ecfZWQkttDp6PWujaCUcXrptSoTKUuYjXp8fMKsz3wJvYpnpxsMQUbD"
const wallet2_accountKey = "tpubDDQHqrK6Xj7A9tfW2zkiZiBPs475QJ8EQ5obViboBxgA1BG5Ai1BnPqBWKTVf6ecEi8XoKK9WQP7GK5jYgdjaoegqBH1EvhVCx2PLc3Zgru"
const type='multisig'

const options_wallet1 = {
    ...
};

const options_wallet2 = {
    ...
};

const result1 = await walletClient.createWallet('wallet1', options_wallet1);
const result2 = await walletClient.createWallet('wallet2', options_wallet2);

// ADDING SHARED KEYS
const wallet1 = walletClient.wallet('wallet1');
const wallet2 = walletClient.wallet('wallet2');

const wallet1_account = await wallet1.getAccount('default');
const result3 = await wallet2.addSharedKey('default', wallet1_account.accountKey);

const wallet2_account = await wallet6.getAccount('default');
const result4 = await wallet1.addSharedKey('default', wallet2_account.accountKey);

// GENERATING P2SH WITH KEYRINGS
const wallet1_address = await wallet1.createAddress('default');
const wallet2_address = await wallet2.createAddress('default');
const ring1 = KeyRing.fromJSON(wallet1_address);
const ring2 = KeyRing.fromJSON(wallet2_address);
const pubKeys = [ring1.publicKey, ring2.publicKey];

const multiSigScript = Script.fromMultisig(m, n, pubKeys);
const base58addr = multiSigScript.getAddress().toBase58('testnet');


texts: Bitcoin QT wallet crashed. Recovered using Bitcoin Core. Now password rejected!

texts:
My encrypted Bitcoin QT wallet crashed years ago but I have backup copies.
It was an earlyish version of Bitcoin QT wallet, first transaction on it is 09/2012.
I have loaded the backup into Bitcoin Core v0.14.1 (64-bit)
Full transaction history is there, wallet has synced.
The password is rejected.
I wrote out the password exactly for safe keeping so I know it is correct and never changed it. There are a number of send transactions so it seems I must have used the passphrase a few times.
Have entered in every imaginable variation.
Could it be because of the upgrade from QT to Core?


texts: Bitcoin Withdraw and the deposit address timed out

texts: I brought Bitcoin on Bitbuy and I made a withdrawal after that to send the money to my forex broker and the broker had a limit of 30min on the deposit. 30min passed and I didn't receive anything. Now, I don't have the bitcoin in my Bitbuy account, it just says pending on the transaction. Can you please clarify what should I do?


texts: What prevents miners from mining more bitcoin after 21million btc?

texts: What prevents miners from mining more bitcoin after 21million btc was mined?


texts:
Does anyone know how to use multiple GPU's with oclvanitygen? I have these two:

Available OpenCL platforms:
0: [Intel(R) Corporation] Intel(R) OpenCL
  0: [Intel(R) Corporation]       Intel(R)
  1: [Intel(R) Corporation] Intel(R) HD Gra
1: [NVIDIA Corporation] NVIDIA CUDA
  0: [NVIDIA Corporation] GeForce GT 630M

What would be the command for using both of them if I want an address that starts with 1MYbtc?


texts: I want to launch my own simple sidechain pegged to bitcoin for testing purposes. Can it be done?

texts: I've been reading about Blockstream and Liquid but I was under the impression that sidechain was something that would require changes to the Bitcoin Core platform. Is that correct? I mean, is the bicoin blockchain already supporting a "peg" to another sidechain? Can I already launch my own sidechain like Blockstream did?


texts: Constructing a P2WSH address from the BIP173 spec

texts:
The BIP173 specification defines how to create Bech32 Segwit native addresses.

In the examples section a public key is given: 0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798.

Based on that key it is somewhat easy to generate a P2WPKH address, one hashes the key with SHA256, then with RIPEMD160 and use the hex decoded result as the witness program (first two commands are simple CLI and the last is from the Dart bech32 library):

$ echo 0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798 | xxd -r -p | openssl sha256
(stdin)= 0f715baf5d4c2ed329785cef29e562f73488c8a2bb9dbc5700b361d54b9b0554

$ echo 0f715baf5d4c2ed329785cef29e562f73488c8a2bb9dbc5700b361d54b9b0554 | xxd -r -p | openssl ripemd160
(stdin)= 751e76e8199196d454941c45d1b3a323f1433bd

Segwit('bc', 0, HEX.decode("751e76e8199196d454941c45d1b3a323f1433bd"))
// bc1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3qccfmv3

Generating a P2WSH involves the script key OP_CHECKSIG followed by once SHA256 hashing. I'm at a loss how to construct said script. The opcode OP_CHECKSIG is encoded as 0xac. But appending that to the key seems silly (and doesn't work). Besides the CHECKSIG opcode requires two parameters. What do I hash?


texts: Why is 'script' used in a transaction instead of the output address?

texts:
I see transactions contain script for each output, but this "script" seems to be deterministically derived from the address associated with the output.

Why does the bitcoin protocol opt for the use of this script-derivative in the transaction instead of just using the output address plainly?


texts:
Hi my configured jsonrpc is following

maxconnections=200
maxuploadtarget=20
rpcuser=someusername
rpcpassword=somepassword
daemon=1
keypool=10000
walletnotify=curl "https://someurl.com/walletnotify?transaction_hash=%s"
blocknotify=curl "https://someurl.com/blocknotify?transaction_hash=%s"

I am getting notified on both wallet notify and block notify but the problem is the transaction is not the same for both. For Example I get f793d590bacffce8efd37c1b1e3db254950e925dd5bbd7f3a92c1db142f4dc37
from wallet notify and

00000000000000000038ffec8f035d54558a78e94ae1138ac5bdf1470fb0863f

from block notify. Please help what have I missed or done wrong here?


texts: Intermittent error "min relay fee not met" even with decent fee and custom Electrumx+Bitcoind

texts:
I have an automated system that sends BTC payments via Electrum for a client.

Now, it happens again and again that payments keep failing with "min relay fee not met" (RPC call failed: {"code":-32603,"message":"Server error: File \"/home/ubuntu/.local/lib/python3.6/site-packages/electrum/network.py\", line 871, in broadcast_transaction | electrum.network.TxBroadcastServerReturnedError: min relay fee not met\n"}) for minutes or hours, and later it will work again.

A few facts:

The fee is taken from Electrum's getfeerate with fee_method: 'eta' and fee_level: 1 (this is already increased from the previous value), and it's actually afterwards inflated by another 20% by my code.
At first I thought it's an issue with Electrum servers. Now I'm using my own ElectrumX instance, and it happens there as well (I didn't find any way to set a fee limit). I then read that it is related to custom settings of Bitcoin nodes, but I'm now using my own Bitcoin node with default settings.
An example of a failing transaction would be this one: https://www.blockchain.com/btc/tx/d45a03bade61a2306994afa52cfd0f7cac18ec6965ec0425ae2010937f3afbad << this is when the transaction was successfully sent a few hours ago, but previously, around 12 hours ago, it kept failing - with the same fee: 45.853 sat/B - 11.463 sat/WU - 225 bytes

If I look at bitcoinfees.earn.com I see the "normal" fees around 20 sat/B, yet the 45 sat/B TX didn't go through. Even if the fees had jumped a bit, it's not logical that I see transactions like this one being successfully broadcasted at a similar time at which mine continued to fail, with only 3 sat/B...

Do you have any ideas what I could do about this problem? Of course I could react on this error by increasing the fees incrementally but this would cause trouble with my calculations and also it doesn't seem logical that I would have to pay a fee of 100+ sat/B when there are TXs with <10 sat/B at the same time...


texts: why a website for buying bitcoins is asking for my CVC code

texts:
I am trying to create an account on coinbase to buy bitcoins (in france). But coinbase is asking for my cvc number while creating the account, not for a purchase.
I am afraid for security issues, as I have been told to not give the cvc to anyone.
Can any one explain please?
Is there a way to avoid that?
Thank you in advance...


texts: Is there an easy-to-use tool for creating and signing offline transactions?

texts: From what I understand, signing a transaction offline means I don't have to ever expose my private keys to a web-connected computer. From what I've found, the only program that allows something like this with WIF keys is sx, are there any other tools that perform something like this? Or is sx the only way do accomplish this?


texts:
Has anyone experience using the Bitcore API for Escrow purposes with node.js?
I assume, you'd need to create a new a address, then somehow create a new transaction using the newly created address, the probe that address for it's balance until its fulfilled.  I've had a look over the docs, but couldn't find anything.  Currently you can run bitcoind on a server and connect to this using RPC, but I'd like to try using Bitcore instead but achieve the same result.
Thanks.


texts: What to do if my BitCoin Address is only 33 digits?

texts:
I noticed that BitCoin addresses usually are equal to 34 digits and/or characters.
I decided to get an extra address and was a bit hesitant to use it since it's 1 digit or character short, is this usable or should I just get another address instead?


texts: cant see bitcoin after restore of backup

texts:
I made a backup of my Qt wallet. The blockchain never got completely downloaded and i was sent a bitcoin that i never saw in my wallet as the downloading of the blockchain never caught up with the transaction. I placed this backup file into another Qt wallet that was fully up to date with the blockchain, thinking that i would see the bitcoin but I only see my bitcoin address.
Can anyone please tell me how this is?


texts: How to access bitcoin wallet on an android that became unresponsive?

texts: My Galaxy S4 mini suddenly stopped working for no apparent reason. It won't turn on via any recommended action or new battery, recovery software from the laptop can't seem to connect as a result. I had bitcoin wallet installed on it with bitcoins inside. How do I access/recover the wallet - or at least coins? Thank you!


texts: Does Ripple use an RDBMS? If so, which one?

texts:
Do Ripple servers use RDBMS?

If so, which one?

I think I remember reading that Bitcoin uses some sort of file database.  Same for Ripple?


texts: Micro-payments definition and ideal platform

texts:
Have developers come close to reaching a consensus on either:

The definition of micro payments?
Whether micro-payments ideally belong on the main chain or side chains?


texts: Need sample compressed and uncompressed Public / Private key pairs for BigInteger

texts:
I am testing a different version of BigInteger that has different endian formats and the native implementation likes to add or remove zeros from the final output.

Can anyone provide some sample public and private keys  (not just addresses)

Compressed
Not compressed
Leading one or more zero (some implementations of BigInt mess with this) for pub and priv
Trailing one or more zero (some implementations of BigInt mess with this) for pub and private
Anything that might look "negative" when BigInteger converts an array into it's two's compliment version

A compressed version of the above would be greatly appreciated... leaving me with 8 tests.

Anyone with data that might be interpreted as a twos compliment for BigInteger, exposing bugs in the code, would be appreciated as well.

I'm doing this so the ported version of the QT client will prevent me from creating unspendable addresses.

Whomever posts the test vectors for this will likely also assist developers on other platforms (Javascript, Java, C#, etc) and their native versions of BigInteger


texts: How does Bitcoin read from/write to LevelDB

texts: I know that Bitcoin Core uses LevelDB since 0.8 version. However, I couldn't find detailed explanation about how Bitcoin stores and retrieves from LevelDB. E.g. If B transaction uses an output from previous transaction A as input, how does Bitcoin lookup this transaction and see if it's spent? After transaction B is spent, how does this transaction get updated?


texts: how can i track a bitcoin sent to someone claiming not to have seen it

texts: i transfer bitcoin to account 3CcKWXXC1BXvctthfaFyeWYXG8mZWT1HUU and he claim not to have seen it for 2 days. i have tried to look for the causes of this but i can see that it has been deliver to him just pretending not to have seen it


texts: What happens when a request expires in Electrum, then I am paid?

texts: I just bought bitcoin from the bitcoin website, and it is taking a lot longer than I expected to process my information and my request and actually send BTC to my wallet.  I set the "expire" setting to 1 day when I was requesting in my BTC wallet.  What happens if I am paid after the request expires?  Is the address no longer used by my wallet?  Does the BTC go somewhere else?  Or does it go no where at all?


texts:
My understanding of the double spending problem is as follows:

Suppose account A has 1 Bitcoin and sends it to account B and  then creates another transaction which sends the same Bitcoin to account C. Some nodes may be notified about the first transaction first while other nodes may be notified of the second transaction first, leading to a conflict regarding which transaction actually occurred first and is the legitimate one.

If I understand correctly, mining solves this problem by forcing each miner to choose between one of the two transactions. But what happens if two miners receive two distinct transactions (A -> B  vs. A -> C) and produce a hash at exactly the same time  - won't each one still record a different sequence of events?

On a similar note, what happens if miners disagree about who produced the hash first? What happens if two nodes produce a hash at exactly the same moment? Some nodes will say miner x mined earlier others will disagree so how is this issue resolved? How does it end up that all nodes eventually agree unanimously and we don't constantly end up with different versions of the block chain?


texts: Can I see all transactions not included in a block yet?

texts: I'm running bitcoind and would like to see which transactions I've received but haven't been included in a block yet. Is that possible, or do I need to run special mining software to see that?


texts: I just sent moneygram to zipzap to go to btc-e but my money is not showing up. It shows on zipzap's site that my payment slip was paid but I can't figure out where my money went. Can anyone help?


texts: Low fee Electrum wallet transaction disappeared, now when I increase the fee it seems to be rejected as a double spend

texts:
Can anyone tell me what is happening with my transactions ...

First I move some small amount and didn't see that fee was set up to low so it was "low fee" after that I've made another one and It get status "parent ....". I've read about fees and all that stuff so only thing I could do is wait, after 24h those two transactions disappeared and my balance went back to what it was before those two transactions.

I thought that they where cancelled so I made another one with higher fee. After that when I've check it at blockchain it had "double spender" tag and in electrum was "unconfirmed". After another 24h once again that transaction disappeared and my balance went back. Today I've tried to move my btc to another wallet .. made transaction with high fee and is still unconfirmed and I'm unable to see it in blockchain. Can anyone tell me what I'm doing wrong? My previous 15 transactions went without any problems ...


texts: How does Bitcoin verify that a user owns the bitcoins he/she spent?

texts: I'm making my own blockchain based currency for a school project and kind of hit a roadblock. I have a wallet class which initializes with zero coins. What prevents the user from just sending a transaction, if he doesn't own the spent coins. Bitcoin is anonymous, so it doesn't save the balance of each account, right? So you could just reprogram a wallet to not subtract the spent amount from your balance? How does Bitcoin prevent this? Thanks in advance.


texts:
In the main.cpp bitcoin code, there are a few different functions for managing blocks.

ProcessNewBlock()
AcceptBlock()
CheckBlock()
ConnectBlock()
DisconnectBlock()

What is a good summary for what each of these methods do, and the differences between them?


texts: Is Bitcoin's value the same, country to country? If not, which valuation is correct?

texts: Does a bitcoin have the same value in every country? Is it not like real money that we use in real life? Does it have a different value in every country?


texts: Multi-signature and "pay to script hash" vs "pay to pub key hash"

texts:
If I understand correctly, there are two methods to perform a multi-signature transactions in Bitcoin. One is "pay to pub key hash", which is a method commonly used to send standard single signature transactions. The other is "pay to script hash", as specified in BIP 16.

If you use "Pay to pub key hash" , any senders to the multisig address need to specify all the public keys involved in the multisig address, which can be cumbersome. If you use "pay to script hash" , the sender only needs to know the hash of the script , which is equivalent to the length of a single bitcoin address.  Obviously, "pay to script hash" fits better with the various infrastructure already setup around the standard transaction.

Are there any other advantages or disadvantages between the two methods?


texts:
Perhaps an ignorant question, my background is in finance not cryptography.  After a transaction is made and "signed" with the sender's private key, how can other nodes verify it without knowing the private key?

It seems in all the videos / text I've reviewed in trying to better understand Bitcoin & blockchain tech, people quickly gloss over the transaction verification piece and don't really explain how it works.

Thanks.


texts: To what extent does asymmetric cryptography secure bitcoin transactions?

texts: Is there a specific attack or bug which asymmetric cryptography prevents during bitcoin transactions?


texts:
What is meant when the nodes select the chain with the highest cumulated PoW?
How is the highest highest PoW calculated? I thought the concept itself is called PoW.


texts: When I review sites like fork.lol and they speak of Mining Profitability of BTC and BCH, how are these calculated? I am trying to figure out how mining profits change between these two coins and how someone determines which one is more profitable, and why the highest profitability switches between BTC and BCH?


texts:
Apart from running a private testnet-in-a-box there are also the public testnet instances. You can use this instead of the regular (production) bitcoin network by setting testnet=1 in your bitcoind configuration file. However, the fact that there are multiple instances and not just one testnet can be confusing.

Is it my version of bitcoind that determines which testnet I am on, or something else?

How can I see which testnet I am using?

Is it possible to switch testnet? If I was on testnet 2 and wanted to use testnet 3 would it require upgrading bitcoind? Would upgrading bitcoind automatically bring me over on the new testnet, deleting all my old blocks, transactions and coins from the old one?

Are there other bitcoin clients that support testnet and if so which one(s) do they use?

If I want to use blockexplorer or something similar, do they only support the "latest edition" testnet?


texts: How is a NXT account address generated? Why do we need to send out a transaction in NXT to secure the address?

texts:
I'm setting up an account and noticed:

The recipient account is an unknown account, meaning it has never had an incoming or outgoing transaction. To submit this request you must supply the recipient public key also.

Please correct me if this is right or not. So when setting up my first NXT address, it creates a public + private key on my local machine. Now the public key is used to generate my NXT address like this:

NXT-XXXX-XXXX-XXXX-XXXX

So does this mean my public key which is a 64 character like this: 18c6e5c1840d044243434dc352672c0b889e332249f240600149baaf978d8870

used to generate the shortened NXT address? (ex. NXT-XXXX-XXXX...)

Is this the reason why even if I gave my NXT address to someone, it wouldn't work since I never sent a transaction out with my public key which also broadcasts my NXT address to show it exists?

I'm still very confused in the fact of why I have to send out a transaction to secure my NXT address. In bitcoin we don't have to do that and I want to understand why this is the case. Was it meant to make it easier to type out? Why didn't NXT just stick with using just the public key as the address?

It seems like its a 2 step process as we have to first generate a public+private key then use those keys to generate a NXT address, and then broadcast this NXT address to the network to register it saying "this NXT address belongs to this public key". Right?


texts:
I am attempting to make Bitcoin-RPC commands in the Windows 10 terminal using Bitcoind from the Bitcoin Core. However, whenever I start C:\Program Files\Bitcoin\daemon>bitcoind the terminal hangs and doesn't print anything. I've waited several hours and the terminal keeps loading and doesn't allow any input. I've also tried typing C:\Program Files\Bitcoin\daemon>bitcoind -daemon but -daemon is not valid Windows command.

I've also tried querying Bitcoin-cli with C:\Program Files\Bitcoin\daemon>bitcoin-cli getinfo but I get the error:

C:\Program Files\Bitcoin\daemon>bitcoin-cli getinfo
error: couldn't connect to server: EOF reached (code 1)
(make sure server is running and you are connecting to the correct RPC port)

So, after researching and reading other Stack Overflow questions I decided to check my bitcoin.conf file. I didn't have one, so I created one and placed it in the C:\Users\User\AppData\Roaming\Bitcoin directory. My bitcoin.conf file looks like:

rpcuser=user
rpcpassword=pass
rpcallowip=127.0.0.1
rpcport=8332
rpcthreads=10
server=1

But i'm still getting the same errors. Does anyone have any idea on what i'm doing wrong?

Update:

I typed in tasklist into the windows terminal and bitcoind.exe and Clientcore were running. Then I typed :C:\Program Files\Bitcoin\daemon>bitcoin-cli -rpcuser=user -rpcpassword=pass -rpc
port=8332 getinfo, but got another error:

error code: -28
error message:
Verifying blocks...

Update:

I tried C:\Program Files\Bitcoin\daemon>bitcoin-cli -rpcuser=user -rpcpassword=pass -rpc
port=8332 getinfo again a couple minutes later and it worked.

I opened one terminal and ran bitcoind, and another terminal I make the getinfo command and everything works


texts: Why is DiabloMiner using so much CPU now?

texts:
DiabloMiner uses about one 50% of CPU on my system (distributed among 2 cores). I could have sworn that it used almost no CPU (1-2% max) in older versions, but I'm not really sure if I should report this as a bug or not. So, is it normal, or am I correct in remembering that GPU miner should not use more than 1-2% of CPU while mining?

Link: Possibly related question.


texts:
Originally posted to StackOverflow but with no response. Thought I might have better luck here.

I've successfully created a Bitcoin transaction in C# according to the protocol specifications. Here's the transaction in binary:

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

I know the transaction is solid because the BTCs were transmitted properly. Furthermore, pasting my transaction above into this validator indicates the correct values.

What's stumping me is how the official transaction ID is generated. Everything on the Bitcoin and StackOverflow StackExchange sites indicate that it's generated by hashing the transaction bytes twice. I tried to do so as follows:

const String txHex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

SHA256Managed sha256Hasher=new SHA256Managed();
Func<byte[],byte[]> doubleHash=(bytes)=>{
    return sha256Hasher.ComputeHash((sha256Hasher.ComputeHash(bytes)));
};
String txidHex=Utils.ToHex(doubleHash(Utils.FromHex(txHex)));

Utils.ToHex() and Utils.FromHex() are helper functions copied from StackOverflow which convert between byte[] and a hex string.

The code above yields a txidHex value of 27E6C3EF18D14FB49CBAC182BBDB47FC9D6F79DA65C101873207B60A957852A7 but searching BlockExplorer.com for that particular txid yields no results.

I mentioned earlier that my transaction did execute properly. It turns out that it did so using a txid of 11172aed3a61fe64ae82cb02e886757d352a4452f956a0703d0809880538ba58. If you paste that txid into BlockExplorer you'll see my transaction.

Which leads me to my question: Given a valid transaction byte stream (byte[]), how does one correctly compute a transaction ID?

Thanks.


texts: Encoding my Bitcoin Address with Base58 encoding

texts:
I am trying to convert my Bitcoin Address with BitcoinJ in order to look like a normal address such as this:
1J7mdg5rbQyUHENYdx39WVWK7fsLpEoXZy.

I haven't found anything exept for the Base58.encode() which takes the getPubkeyHash() of my ECKey and returns something like this:
5ahorsFsHTcG3f662evowc5c9zf.

Which means that encodes the given bytes in base58,no checksum is appended according to the API.But i want my address to look like the above one.

Is there any algorithm in java  for encoding address_byte_string (consisting of 1-byte_version + hash_or_other_data + 4-byte_check_code)?

according to this:https://en.bitcoin.it/wiki/Base58Check_encoding


texts: Possible to get Blockchain bitcoins over to Stripe or Paypal?

texts: I'm new to the Bitcoin world. I accepted a Blockchain transfer over the weekend as payment for something. I'm wondering if it's possible to get my Blockchain Bitcoins (well, fraction of a bit coin) over to my Stripe account or PayPal account?


texts: What is meant by "Maintenance" of a Crypto Currency Wallet?

texts:
I have invested in AltCoin XtraBYte XBY on c-cex.com exchange. My account now as XBY funds frozen because the XtraBYte Wallet status is on "Maintenance".
see https://c-cex.com/?id=ws
Where maintenance is a pretty straightforward word that is clearly understood in English, it remain another thing when we are talking about a cryptocurrency wallet. What exactly do we mean by an account on maintenance? What does it involve? Why a wallet would need to have maintenance? Why would users account be frozen because of a currency under maintenance?
Thanks for your help


texts: How might Bitcoin be made impervious from attack by large monied interests that could atttack with a brute force majority hashrate hack?


texts: Blockchain.info API: How to cancel callback notifications

texts:
Regarding Blockchain.info's Receive Payments API V2:

The 'Generating a Receiving Address' feature requires a callback_url, to which they send a notification of EVERY confirmation. For every transaction, potentially thousands of notifications will be sent to the callback_url.

When I use the 'Generating a Receiving Address' feature, can I receive a new address WITHOUT specifying a callback_url?
If I must specify a callback_url:
a. Is there any way to cancel the callbacks?
b. Can I limit the number of notifications that are sent?


texts: ScriptSig (coinbase) structure of the Genesis Block

texts:
From original bitcoin c++ source code:

// Genesis Block:
        // CBlock(hash=000000000019d6, ver=1, hashPrevBlock=00000000000000, hashMerkleRoot=4a5e1e, nTime=1231006505, nBits=1d00ffff, nNonce=2083236893, vtx=1)
        //   CTransaction(hash=4a5e1e, ver=1, vin.size=1, vout.size=1, nLockTime=0)
        //     CTxIn(COutPoint(000000, -1), coinbase 04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73)
        //     CTxOut(nValue=50.00000000, scriptPubKey=0x5F1DF16B2B704C8A578D0B)
        //   vMerkleTree: 4a5e1e

...

txNew.vin[0].scriptSig = CScript() << 486604799 << CBigNum(4) << vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));

We could see that scriptSig is: 04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73

Let's see closer:

04 - ?

ffff001d - 486604799 aka 0x1d00ffff

010445 - ?

5468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73 - The Times 03/Jan/2009 Chancellor on brink of second bailout for banks

I don't understand what are 04 and 010445. How can I get them?
At wiki page of Genesis Block (https://en.bitcoin.it/wiki/Genesis_block) in ScriptSig line there is nothting about 010445.


texts: What am I doing wrong when calculating the BitCoin Base58 Private Key?

texts:
I have this:

const crypto = require('crypto')
const bs58 = require('bs58')

const a = crypto.randomBytes(32)
const b = crypto.createHash('sha256').update(a).digest('hex')
const c = '80' + b
const d = crypto.createHash('sha256').update(c).digest('hex')
const e = crypto.createHash('sha256').update(d).digest('hex')
const f = c + e.substr(0, 4)
const bytes = Buffer.from(f, 'hex')
const address = bs58.encode(bytes)
console.log(address)

Which was inspired from this. But when I do this:

 bitcoin-cli importprivkey "<key>" "foo"

I get this:

error code: -5
error message:
Invalid private key encoding

What am I doing wrong?


texts: Purchased a Bither bitcoin machine and can't figure out how to work it.  I keep getting bitcoins but don't know how to send them to my Coinbase wallet and therefore exchange them for cash.  Help


texts: Now that the hard fork is coming Will replay attacks if not dealt with destory the coin's value?

texts:
As we all know there's a hardfork coming our way this November.
My question is now that the hard fork is coming Will replay attacks if not dealt with destory the coin's value?
Because if this issue won't be fixed and fast and people could make this so called "Replay attacks" there won't be any point of making a bitcoin transaction since it won't be as "safe" and one coin could lose it's entire value.
Are prices going to drop? and what's the possibilty of these attacks to actually being a reality?

Thanks.


texts: Has anyone written an utility or something able to search/identify which Derivation Path an Address belongs? For example, giving a mnemonic like "unaware open elite rabbit grunt spread session exotic legal satoshi trend electric" and Address "12rfNtgHFjLoK1y58S3gHijmGHV8t8iteT", the program should return its Derivation Path "m/44'/0'/1'/2/6".


texts: What backward compatibility testing is done on Bitcoin Core?

texts:
The unit and functional tests of the latest release of Bitcoin Core obviously test the codebase of that release.
What backward compatibility testing is done to ensure the latest release passes previous releases' versions of the unit and functional tests?
And conversely what backward compatibility testing is done to ensure previous releases pass the current unit and functional tests?


texts: Bitcoin-qt -how does it choose the address to take money from when sending btcs

texts:
I don't have any bitcoins yet, but I have the the wallet program called bitcoin-qt. I am wondering about the send feature. It does not seem to let me choose which address to deduct the coins from. How does that work?

Let's say I have 5 addresses and one coin in each and I want to send 5 coins. Does it automatically take 1 coin from each of the addresses? What if I want to take coins only from specific addresses?

Actually now looking at it more closely it doesn't even show which address contains coins and which one doesn't. Isn't this a bit oversimplified?


texts: Transaction unconfirmed after almost 2 day! Help!

texts:
I tried to send a bitcoin transfer Wednesday evening and it is still unconfirmed. It says "fees 0" but I have my block chain account set to "use recommended fee" by default. Can anyone help me get this confirmed? If greatly appreciate it!

Here it is: https://blockchain.info/tx/f054dbba378cea1b82168214cf28771f60c7cc30be0963b0b38498c7a0ec9166


texts: Pending transaction and it been 8 day, anyone can help me here and here 3MPTn2ZwQiydkvKZKRgAVUQawA9ShjLJVh , need help


texts: Can we transfer cyptocurrency to anyone so long they  hold an e-wallet, even in different part of the world?


texts: HOw to convert BItcoin to cash or bank transfer

texts:
I am in India and 1 of My US customers wants to pay me in Bitcoin.. so my questions is:

can i take Bitcoin? If Yes then what is the procedure of that?
Client is asking for the Account in which he can transfer it. Where and how to open that account?
How can i convert the Bitcoin in INR (Cash or bank transfer)

Please help.


texts: How do I handle the risk that my hard disk crash?

texts:
I have good back up system. Can my wallet be backed up?

Can I access it anywhere?

If so how do bit coin system know that I am the one accessing it?


texts: Block messages with transactions hashes instead of full transactions

texts:
When a bitcoin node has the blockchain in sync, most transactions in incoming block messages may have been already received as standalone tx messages before.

With a block message with only transaction hashes, the receiving node could try to reassemble the full block with its unconfirmed transactions and just request the missing transactions to complete the block.

Since this way to save bandwidth looks too obvious, I'm guessing there must a reason to always include the transactions in block messages, even after downloading the blockchain.


texts:
I have been scammed 6 months ago.
Now someone is calling me from BTC REFUND DEPARTMENT. He said that I have under my name the bitcoins that have been scammed. But the way to take this amount is to synchronise my wallet with the address that the amount is under my name. The issue is that he is asking for 10% of the amount to be added in the wallet and send the new bitcoins to blockchain and then after 15 minutes all the funds will be in my wallet.
Has anyone had a similar experience? Is this true or is just another scammer?


texts: How can I use PSBT in a JavaScript project?

texts:
I am trying to use PSBT in a Bitcoin project.
The idea is to generate keys and sign transactions client-side.
I am already familiar with bitcoinjs-lib but I find the API rather complicated.
It would be great if I could use bcoin which is usually more clear and straight forward.
I checked the bcoin docs but I found no mention of PSBT.
Is there a way to use PSBT in bcoin?
If not, is there any elegant workaround?


texts:
Bolt #11 defines a "tagged field," n, which identifies the payee by a public key, but it isn't required.  It also requires a signature which can be verified only if the public key is known.  When tagged field n is not included, something called "signature recovery" is required.  How does that work?

I ask because I was thinking that if I get two invoices, I should be able to determine if they indicate the same payee.  I thought tagged field 'n' would be great for this, but it might not be supplied.  So how can I compare the two invoices to see if they came from the same node?  If signature recovery is built in, I guess that means I can get the public key even if tagged field 'n' is missing.  But how would I do that?


texts: Are there any properties of cryptocurrency that can help prevent accumulation of wealth by a few individuals?

texts:
Over time there seems to be a trend towards consolidation of wealth to a small number of individuals in human society.

Are there cryptocurrencies with any properties that could help prevent that happening?

Or, are there any properties a cryptocurrency could have that would achieve that aim?

Some years ago, there was a cryptocurrency called Freicoin that had built in demurrage, where the value of currency held by an individual would decrease over time. I understand this was intended to encourage spending rather than saving.

Possibly the concept of demurrage is a valid one even if the Freicoin cryptocurrency project was essentially unsuccessful in remaining viable. I suspect that due to the nature of demurrage, it may require people to choose to use the currency because they thought it was good for society rather than as a way to earn wealth with little work.

To be clear, I'm not asking this question to raise a discussion, I'm asking it to learn out about any discussions that have occurred or concepts that have already been considered.


texts: dumpwallet lists HD keys in seemingly random order

texts:
I was curious when you do a dumpwallet in the default bitcoin client the output file gives you an xprv and then followed by WIF keys, corresponding address, and the hdkeypath.
I noticed the order of the keys are not sequential with the keypath. For example when I did a dump of a test wallet with no balances I get:
hdkeypath=m/0'/0'/390'
hdkeypath=m/0'/0'/489'
hdkeypath=m/0'/0'/779'
hdkeypath=m/0'/0'/48'

Is there a method behind the order or is it all random?


texts: Are really all transactions (the whole blockchain) stored on every client?

texts:
I've read through some explanations saying that every client in the network knows every transaction because when someone wants to perform a transaction, he sends that informationen (how much, to whom and his own address) to everybody he knows and everybody they know and every.... and so on. Until it gets confirmed by everybody in the network. Then the transaction can take place. So everybody in the network knows that this transaction happens, and add the new block to their chain.

Does REALLY everybody have the whole history of transactions (a.k.a one HUGE chain of blocks) stored on their (lets say) computer?

Really all? Isn't this amount of bytes too much for normal hard disks (in my computer, smartphone, ...) considering ALL transactions which have ever happened and happen?


texts: Build a wallet for Android and iOS for a self-made cryptocurrency

texts:
I've built a cryptocurrency of my own using this video guide. I did the first 4 steps out of 6, as the 5th level is about building a wallet for Windows platform.

I have started creating this cryptocurrency so it would be able to trade using it only on mobile devices running Android and iOS. Right now I would like to start to develop it for Android platform.

My question is how can I create a wallet for Android using Java that will support my self-made cryptocurrency? By wallet I mean to store the coins, send and receive them, and ability to open new wallets.


texts: Can I download the blockchain blocks from torrent and paste them?

texts: Currently my Bitcoin Core client was stopped syncing at 40.73%.  It was not progressing any more.  I've downloaded the Blockchain from https://getbitcoinblockchain.com/ .  Can I just copy these blocks and paste these downloaded blocks to my Bitcoin > Blocks ?  Will everything be fine ?  Will the Bitcoin Core client accepts the downloaded blockchain ?


texts: Does sending coins to someone incur fees?

texts:
Some noob questions.

If I send someone coins, will it incur fees?
If it incur fees then is it true for all other coins too?
If it incur fees then can I set fee for the transaction?
If I can set fee for transaction then what will be its impact if the fees is low or high? What if I set no fee at all?


texts: What's the best Android wallet client for bitcoin?

texts: There are many bitcoin wallet clients on android market. What is the best considering security, interoperability and usability?


texts: Is extranonce sometimes necessary for blocking?

texts: Is extranonce ever necessary to find a block, e.g., in cases where exhausting the regular nonce range fails to block? Is this the rationale behind extranonce?


texts: Upgrading Bitcoin Core (from a rather old version) and pruning at the same time?

texts:
I have an old Bitcoin Core wallet (v0.15.1) with 500 GB of blockchain on my computer (A new-ish mac - stupidly just copied the same bitcoin core version over when I upgraded my computer rather than downloading the latest version).
I'd like to upgrade to the latest version (0.20.1) so I can use it again, but want to make sure I'm not doing anything stupid! The wallet has an existing balance, although according to the blockchain the address on the wallet is missing a transaction that must have come through after it was created - it's a backup of a wallet from an old computer that is out of commission. I've backed up the wallet again using Bitcoin Core's backup feature. The original wallet.dat file was from about 2014. I only have about 100 GB left of space on this hard drive, and would ideally love to be able to prune the blockchain stored as I'm upgrading.

Is it possible to upgrade from v15 - v20 directly by just installing the new version?

How can I prune the insanely large blockchain as I'm upgrading? Will the new version try and add to the size of the blockchain stored already if I don't do anything? I don't have enough room for two 500GB blockchains! I could just delete the old Core wallet (keeping a couple of backups of course!) but that just makes me nervous.

Many thanks!


texts: I'm trying to understand Bitcoin a bit more and I'm struggling to find an answer for this scenario. Say for example I have access to a wallet and I have give a person on the other side of the world access to the same wallet (both using bitcoin core wallet and bitcoin-cli sendtoaddress). We are on our phones and we both have the exact same balance and are at the exact same block height. How does bitcoin prevent the scenario where I send money to one address and a person with access to the same wallets sends money to another address at approximately the same time?  Does the first transaction to hit the network win and the later one just never get confirmed? How does the  decentralized network decide?


texts: Is the asymptotic performance of bitcoin O(n) relative to the block chain length?

texts:
If I want the latest information (ie. account balance) of account A do I have to traverse the entire block chain to get that info or is the relevant information store in the latest block or some other companion data structure?

If I have to traverse the entire block chain, is there going to be scalable problem as block chain grows?


texts: Why doesn't Alias register on IGNIS blockchain when using the setAlias API?

texts: I am trying to create an Alias on the Ignis child chain of Ardor. Everything seems to work properly the using the setAlias API in the Ardor API Console. I see the transaction for a brief time in my dashboard and it disappears without registering my Alias.


texts: How to setup, sync, backup en restore blockchain when using bitcoin-qt

texts:
I am trying to setup a Bitcoin client using Bitcoin Core and Armory.

Synchronization with the network seems troublesome. The blockchain is +120GB and corruptions can easily occur. I have tried twice already. Both attempts failed, first at 80%, the next at 28%.

The first became corrupted when I started Armory using the Bitcoin data directory.

On the second attempt there was some unknown error and the blockchain was again corrupted.

Such corruptions seem to require complete new download of the blockchain.

Of course, without a good and synchronized blockchain, Bitcoin Core and Armory will not work.

Is there a instruction somewhere that explains in detail how to setup, sync, backup, restore blockchain data properly?


texts: Auto formatting data into sendmany command

texts:
Apologies for the newb question.
But what's the best way to convert data on spreadsheet (lists of addresses and corresponding amounts to be sent), into a format suitable to be entered as a sendmany command into bitcoin console with the minimum amount of steps?  Ideally would handle any amount of addresses and amounts.
Thanks in advance if anyone can help out at all!

ie

from

1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XZ     0.01
1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz     0.5

to this

sendmany "" "{\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XZ\":0.01,\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\":0.5}"


texts: Novice has bitaddress.org-generated wallet with .08 BTC in it... how can i exchange them for a fiat currency?

texts:
I have the wallet ID and the private key. My wallet contains a fraction of one bitcoin from a single transaction in 2014.
I made an account at blockchain.com, but I'm unable to import my wallet into that account. ("Invalid Wallet ID")
If I wanted to sell, for example, what would I need to do?


texts: To be more energy efficient, wouldn't be a consensual fork - right now - without the reward of new mined btc for each block helpful?

texts:
As the reward is lower, less effort is spend in mining new bitcoins. How the transactions fees will evolve would be quite crucial the get the miners activity down (and their energy consumption). I would assume that the transactions fees would stay at very low levels, because every miner has always an incentive to add any transaction with a positive fee.
Additional question: For sure there are some cryptocurrencies which reached that state (of no mining new coins). How did the transaction fees evolve after mining the last coin?


texts: What were the previous Binance coin burns as stated in the white paper before 2018 April?

texts: What happened to the price prior to the Binance coin burn as stated in the white paper? How high did the coin go in terms of BTC prior to the burn and after?


texts: Does anyone know where this transaction was sent to?

texts: I made a transactions in 2018 9/19 I was wondering if you can figure out where it went to. I'm assuming it was to a trading site. 3MgJe2W6mY7JM2YeXUyAbC2xAAoboi2y5u


texts: Checking pending (not yet in the blockchain) transactions

texts: Is there a service (like Blockexplorer) that shows pending transactions that have not (yet?) been included in the block chain?


texts: How does bitcoin manage the money supply?

texts: All currencies are expanded when institutions begin loaning currency. How will bitcoin limit this growth? In economics there are several definitions of money such as M2, M3, etc.


texts: Sending fund to an existing bitcoin address

texts:
BTC address1 has 2 BTC
BTC address2 has  4.5 BTC
Assume the address is reused, the fee is zero.
Address2 sends 1.5 BTC to address1.
Thus, BTC address1 has 3.5 BTC and BTC address2 has 3BTC
Since BTC address1 is receiving fund, it does not need to sign anything.
The transaction
Input: 4.5 BTC address2 , output: BTC address2 : 3 BTC (return change), BTC address1: 1.5)
How does the blockchain know that BTC address1 got 3.5 BTC?


texts: Are sipa's standardized schnorr signatures incompatible with blind signatures?

texts:
Here, sipa proposes a standardization of schnorr signatures: https://github.com/sipa/bips/blob/bip-schnorr/bip-schnorr.mediawiki

For example, sign() returns Sig{R,s} which can be encoded with 64 bytes (R.x || s) where R.y can be disambiguated via quadratic residue.

After implementing sign() and verify() according to that document, I attempted to implement blind signatures.

However, verifying my unblinded signature fails 50% of the time because of the line return false if jacobi(R.y) !== 1 in verify(), enclosed below.

Here's my pseudocodey impl:

type Signature = { Rx: int, s: int }
type Unblinder = { alpha: int, Rx: int }
type BlindedMessage = { challenge: int }
type BlindedSignature = { s: int }

fn blindMessage(nonce: Point, signer: Point, message: bytes): (Unblinder, BlindedMessage) {
    R = nonce
    P = signer
    alpha = rand()
    beta = rand()
    R' = R + alpha*G + beta*P
    // challenge
    c' = int(hash(R'.x || P || message)) % curve.n
    // blinded challenge
    c = c' + beta
    return (Unblinder(alpha, R'.x), BlindedMessage(c))
}

fn blindSign(signer: privkey, nonce: privkey, blindedMessage: BlindedMessage): BlindedSignature {
    c = blindedMessage.challenge
    x = signer
    k = nonce

    s = k + c*x
    return BlindedSignature(s)
}

fn unblind(unblinder: Unblinder, blindedSig: BlindedSignature): Signature {
    Rx = unblinder.Rx
    s = blindedSig.s + unblinder.alpha
    return Signature(Rx, s)
}

// implemented according to sipa's spec
fn verify(pubkey: Point, message: bytes, sig: Signature): bool {
    pk = pubkey
    m = message
    P = pubkey

    (r, s) = sig
    e = int(hash(r || P || m)) % curve.n
    R = s*G - e*P

    return false if isInfinitePoint(R)
    return false if jacobi(R.y) !== 1 // <-- Fails 50% here
    return false if R.x !== r
    return true
}

Here's the test that will fail 50% of the time:

noncePriv = rand()
signerPriv = rand()
noncePub = noncePriv * curve.G
signerPub = signerPriv * curve.G
message = hash('my message')

// blind
(unblinder, blindedMessage) = blindMessage(noncePub, signerPub, message)

// sign
blindedSig = blindSign(signerPriv, noncePriv, blindedMessage)

// unblind
sig = unblind(unblinder, blindedSig)

// verify
verified = verify(signerPub, message, sig)

assert(verified)

The spec's sign() uses nonce = jacobi(y) === 1 ? nonce : curve.N - nonce to force a quadratic residue y, and I would assume my test fails because 50% of the time it generates a non-residue y. However, I was unable to figure out where and how to apply this in my blind-related code. None of my efforts had an effect on my 50% pass rate.


texts: Are there minimum transaction fee, and is it based on the number of input transaction (UTXO)?

texts:
I know probably everyone give an extra transaction fee, but are there minimum transaction fee that one must pay, and is it based on the number of input transaction (UTXO)?

And I have read that wallet developers tries to eliminate small UTXOs when preparing a new transaction. So is there harm for having too many small/dust UTXOs?


texts: What is the difference between kH/s, MH/s, and GH/s?

texts:
I started mining on a friend's computer and it shows 300 kH/s. But when I research other peoples' hash rates I usually see MH/s. Are these speeds the same as kilobytes and megabytes?

Also, when I say 300 kH/s does that mean 300,000 Hashes generated per second?


texts:
I have a desktop, laptop, tablet, and phone.  I want to be able to send and receive payments from all these devices.

How do I go about doing that?  Do I have to create a unique wallet on each computer?


texts: Help needed with PyWallet and wallet dump using MacOS

texts: Could anyone please give me some guidance on how to perform a wallet dump using PyWallet on a MacBook (macOS 10.12 Sierra)? I’m not very savvy with this stuff at all. Have an old wallet.dat file from 2011 that I want to check all the keys from and was reading that doing a wallet dump would be an efficient way to do it without having to wait for the entire blockchain to sync on Bitcoin Core. Having a really hard time trying to figure out how to do it with almost no computer programming knowledge. So far I have Python 2.7 downloaded but am pretty stuck after that. Any help would be greatly appreciated. Thank you!


texts: Where can I get a visual example of the entire bitcoin network starting from physical network to the overlay network

texts:
*Note I am not a technical person so excuse any misunderstandings on my part here.

I am looking to get a sense of how the entire system looks like as a whole starting from the physical hardware (such as miners and full nodes) to overlaying networks (node transaction relays maybe?) to mobile clients omitting and receiving transaction data.


texts: Is there any way to experiment with the Bitcoin technology without having to buy actual bitcoins for use on the larger bitcoin network?

texts: So, I'm just a curious person at this point, I've only just decided to look into Bitcoin and see how it works and what it does. But I'm not sure if I want to try out things on the larger bitcoin network, where there's real money of real value at stake. Is there a way I can setup a local bitcoin "network", with its own blockchain, etc. for testing purposes?


texts: How does bitcoin handle unspent outputs from fresh transactions?

texts:
I read that Satoshidice uses one of the outputs from the bet transaction to fund the response transaction.

Can anyone provide explanation/reference to how bitcoin handles such transactions.
What is the rationale of allowing such transactions?
If the protocol did not allow unconfirmed unspent outputs to be used, would that make bitcoin unusable?


texts: Does the private key of Bitcoin change everytime the address changes?

texts: I have read from many sites that an address should change every time a Bitcoin transaction is made. Does the private key change along with the Bitcoin address. How is the address obtained from the public key? Is it the same method of deriving the public key from the private key?


texts: How do I find out what the latest protocol version is?

texts: How do I find out what version Protocol specification is describing?


texts: Would first-seen prevent a double spend attack?

texts:
It takes approx. 8 seconds for a transaction to propagate through the entire Bitcoin network. If we got rid of the concept of replace-by-fee and replaced it (no pun intended) with a first-seen approach wouldn't this significantly reduce the likelihood of a double spend?
Even if an attacker is running another wallet on the other end of the planet and broadcasts an identical transaction right near the winning mining node, such a double spend transaction would still reach the merchant within < 16 seconds.
Would a merchant be able to simply listen out for a double spend transaction and conclude with a reasonably high level of confidence that it is very unlikely for a double spend to occur in this case?
Note: This SE question does not address my particular concern as a merchant would be waiting 16 seconds to rule out a simultaneous transaction.


texts: Bitcoin Core full node download crashes all the time

texts:
I'm downloading the full blockchain for the first time, and have only got a couple of laptops with i5 and 8gb ram and a couple of external hdds. The download has run for a long time on one of the hdds (five nights), the other one I started yesterday. The first have reached 58% the other 61% (in one day). The other one, I realized, were downloading it to the internal ssd, so I had to move it because is ditn't have more space. After I moved the download to the hdd it's moving as slow as the original one and at a speed that won't get finished because of continual crashing.

I'm considering continuing the download to an extarnal ssd of 250gb and then copying it over to the 500gb hdd and trying to do the last part on that, but when on hdd it crashes all the time, so I haven't got very high hopes.

Does anyone have any suggestions for me? Is the only bottleneck the hdds or can it be someplace else?

Would it be possible to download the second half only to the internal ssd and them combine them on the hdd somehow?


texts:
Is there any part of the Bitcoin protocol that established a limit on the maximum number of op_codes in a script.

Recently I have hit the limit for the bitcoin core client. In:
https://github.com/bitcoin/bitcoin/blob/ce56f5621a94dcc2159ebe57e43da727eab18e6c/src/script/interpreter.cpp
in line 276 you find:

   if (opcode > OP_16 && ++nOpCount > 201)
        return set_error(serror, SCRIPT_ERR_OP_COUNT);*

I interpret this line as saying that, outside standard type of transactions, there is a limit to 201 operations beside pushing a number from 0 to 16 to the stack.

Is this defined in any part of the protocol or discussed in any BIP?

I know there are limits for multiscript transactions:
https://github.com/bitcoin/bips/blob/master/bip-0016.mediawiki#520byte_limitation_on_serialized_script_size
and that the number of signatures should be limited to avoid certain attacks, but for lightweight operations (OP_ADD and the like) I cannot find any explanation on the limit and the exact 201 value.

P.S: I found the error when trying to spend the offending script. Curiously, I was allowed to send the transaction. It is when the client tries to verify the data for the next transaction when there is a problem.


texts:
I'm trying to setup pushpool + bitcoind.  However, when I connect to pushpool with cpuminer I receive this error:

[2013-04-21 12:47:47] json_rpc_call failed, retry after 30 seconds
[2013-04-21 12:48:17] JSON-RPC call failed: {
   "code": -2,
   "message": "upstream RPC error"
}
[2013-04-21 12:48:17] json_rpc_call failed, retry after 30 seconds

I see this error in the pushpool server log:

root@ip-10-28-79-184:/usr/local/sbin# ./pushpoold --debug=2 --stderr --  foreground --config=/usr/local/sbin/server.json
[2013-04-21 13:26:28.319949] Debug output enabled
[2013-04-21 13:26:28.333064] Forcing local hostname to localhost
[2013-04-21 13:26:28.456350] Listening on host :: port 8336
[2013-04-21 13:26:28.456477] Listening on host 10.28.79.184 port 8334
[2013-04-21 13:26:28.485367] initialized
JSON protocol request:
{"method": "getwork", "params": [], "id":1}

About to connect() to 127.0.0.1 port 8332 (#0)
   Trying 127.0.0.1... * TCP_NODELAY set
 connected
 Connected to 127.0.0.1 (127.0.0.1) port 8332 (#0)
 Server auth using Basic with user 'username'
 POST / HTTP/1.1
Authorization: Basic dXNlcm5hbWV2YXN5YTpwYXNzd29yZHZhc3lhMTQ=
Host: 127.0.0.1:8332
Accept: */*
Accept-Encoding: deflate, gzip
Content-type: application/json
Content-Length: 45

 The requested URL returned error: 500
 Closing connection #0
[2013-04-21 13:26:31.743119] HTTP request failed: The requested URL returned error: 500

bitcoind config:

testnet=0
server=1
rpcuser=username
rpcpassword=password
rpctimeout=30
rpcallowip=*
rpcport=8332
rpcconnect=127.0.0.1
gen=0
keypool=256
paytxfee=0.00

pushpool config:

{
    "listen": [
        {
            "port": 8336
        },
        {
            "host" : "server_ip",
            "port" : 8334,
            "protocol" : "http-json"
        }
    ],
    "database": {
        "engine": "mysql",
        "host": "localhost",
        "port": 3306,
        "name": "bitcoin",
        "username": "mysql_username",
        "password": "mysql_password",
        "sharelog": true,
        "stmt.pwdb": "SELECT `password` FROM `pool_worker` WHERE `username` = ?",
        "stmt.sharelog" :  "INSERT INTO shares (rem_host, username, our_result, upstream_result, reason, solution) VALUES (?, ?, ?, ?, ?, ?)"
    },

"pid": "/tmp/pushpool/pushpoold.pid",
"forcehost": "localhost",
    "log.requests": "/tmp/pushpool/request.log",
    "log.shares": "/tmp/pushpool/shares.log",
    "auth.cred_cache.expire": 75,
    "rpc.url": "http:// 127.0.0.1:8332/",
    "rpc.user": "username",
    "rpc.pass": "password",
    "rpc.target.rewrite": true
}

I have tried to change ports, and even rebooted the server,  nothing helps.


texts: How would you store a very large amount of crypto currency

texts:
I have Litecoin, Bitcoin, Ethereum and NEM. In recent times, I've become a very lucky boy indeed!

I usually download and install the "official" wallets that download the entire blockchain but this is getting impossible now, especially for Ethereum Mist wallet which just plays up all the time causing me to delete chain data and force a so-called "fast sync".

If you were in my position, having this very large amount of coins, how would you go about storing/protecting them? For each of the above which wallets would you use and how would you split things so as to not put everything in one basket?

Many thanks


texts: How does the thunder network work? And how does it keep things decentralized?

texts: How does the new thunder network work? How does it keep things decentralized?


texts: Private key only wallet for Bitcoin Core regtest

texts: I'm running a private regtest network on GCP. I generated a list of 2000 vanity testnet addresses ordered sequentially from prefixes mooo1 to n2ooo with their respective pub/priv key pairs, and to prevent complications, I want to only have one private key for each node (change in outgoing transactions are sent to the original address). Because there's no security concern in my setting (it's just a performance test, no money or attacker is involved), I want to make each bitcoind instance only use a single private key for all transactions, and not generate new addresses through an HD wallet. This is because viewing transactions is much more streamlined. I can tell which node is sending bitcoins to which other node, and diagnose issues more easily. Is there an option in bitcoind to only use a single private key?


texts: What is the daily transaction limit for Bitinstant?

texts:
I know that bitinstant limits individual trades to 3 digits or $999 per transaction, but they make no mention in their FAQ about the size of the daily limit they impose.

I was wondering if anyone knew the exact number?

Note: I think this number may vary depending on where your sending money from, however I'm specifically interested in the limit regarding sending money from mtgox to bitstamp and vice versa.

Update: I emailed them and they confirmed that the limit is in fact $2000 per day.

Update: Since this question bitinstant has updated their service. You can now be verified by sending in a photo idea and have your limit upped to $10,000 per day.


texts: Running multiple BTC nodes on separate VMs on the same host machine?

texts:
I've got a server running 24/7 with lots of resources left. I want to run a full Bitcoin node, but actually, I thought of running a few virtual machines on it (using virtualbox) and running a full Bitcoin node in each of them.

Obviously they'd all need to use different ports (which are to be forwarded to the particular VM LAN IPs by my router).

Will that work, i.e. would they be on different 'metric locations' in the Bitcoin network? (even though they have the same physical location and same IP of course)

Reason for this endeavour: being 'as connected as possible' to different parts of the network simultaneously, just as if I had multiple nodes running on different physical locations throughout the world.


texts: What would it take to track dollars like bitcoins?

texts:
Watching an ATM from a large US Bank accept a cash deposit makes me wonder - what would it take to track dollars like bitcoins?

Said another way, what would a blockchain for fiat cash look like?

When I deposit cash into this ATM, it scans each banknote.  It uses Optical Character Recognition to classify the banknotes by value.  I imagine that the ATM could recognize the serial number from the bill as well, and publish a corresponding transaction to a USD blockchain.


texts:
what is base58Prefixes[SCRIPT_ADDRESS] ? when we use it ?
 base58Prefixes[SCRIPT_ADDRESS] = std::vector<unsigned char>(1,5);

How to generate value  base58Prefixes[SECRET_KEY], base58Prefixes[EXT_PUBLIC_KEY], base58Prefixes[EXT_SECRET_KEY?
 base58Prefixes[SECRET_KEY] =     std::vector<unsigned char>(1,128);
 base58Prefixes[EXT_PUBLIC_KEY] = {0x04, 0x88, 0xB2, 0x1E};
 base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x88, 0xAD, 0xE4};


texts: How exactly trading of Bitcoin does? Is it just like a trading of shares of any company listed on stock exchange? Can anyone explain its transaction in detail?? Is there any Transaction fees or trading margin like stock exchange?


texts: How can a sender know receiver's public key when creating "Pay To Public Key" tx?

texts:
When you create a "Pay To Public Key" transaction, you need to know the receiver's public key. How can we know receiver's public key?

You can get public key hash from address like this, but I'm not sure how to get public key.

FYI: scriptPubkey in P2PK
scriptPubKey:  OP_CHECKSIG


texts: Am trying to start mining litecoin with litecoin-qt

texts:
I have downloaded the litecoin-qt, since I read on a forum, with that I could start mining directly.
But in my screen, there is not a button for mining.

Have downloaded the cpuminer and have placed the file 'minerd' next to the litecon-qt programm in applications. They are together in one folder.

Not sure I have understood it well.

Is there someone that could give some ligth on this matter?
Would be very much appreciated.

thnx Adithya!


texts: How to get bitcoin address from the pubkey_hash using bitcoin-abe or something else?

texts:
I'm using: https://github.com/bitcoin-abe/bitcoin-abe to import the blockchain into a mysql DB it is almost done after 5 days. So I started looking at the data and didn't see any addresses. I know the BTC client doesn't use those, but it still would be nice to have them in another table. I was looking around at the code and found this:

def hash_to_address(version, hash):
    vh = version + hash
    return base58.b58encode(vh + double_sha256(vh)[:4])

In: https://github.com/bitcoin-abe/bitcoin-abe/blob/3004fe4bad6f64d4c032c735ee23bf9f052d825b/Abe/util.py

When I run a pubkey_hash through that function I don't get the expected result of an address. For example taking the following pubkey_hash: 62E907B15CBF27D5425399EBF6F0FB50EBB88F18

I should get: 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa

But instead I get: 6GEZdxx5UiTk3U3LaLfsWwRaFAvXEpPNS5R4mqsJDXVJcTNNngTyB5i9S76MLTq

The script I created is:

import util
hash = '62E907B15CBF27D5425399EBF6F0FB50EBB88F18'
print util.hash_to_address("00", hash)

Any ideas?


texts:
I'm running a ripple node on my own server, and try to conduct some analysis to the balance of all ripple accounts. Thus I need to synchronize the ledgers and analyse them.

Currently, my server has been running on the consensus ledger, and I found the browser /rocksdb. However, I don't know how to extract the data from that browser. It there any GUI tool or example code to do so?


texts: What does bitcoin actually do with these problems?

texts: I understand this might be a simple question but what do cryptocurrency companies do with these problems when you mine. I know you get reward for solving a problem but what will bitcoin do with that?


texts: Why bech32 address always starts with bc1q?

texts:
I understand that it starts bc1.

But 'q' is not what I understand. Can someone explain to me?


texts: How to get the private key in hex from the output of dumpprivkey

texts:
I am trying to create raw transactions according to the excellent answer of runeks here:
How to redeem a basic Tx?

But there he starts with a private key in hex format
18E14A7B6A307F426A94F8114701E7C8E774E7F9A47E2C2035DB29A206321725

and I have one in base58 given by bitcoin-cli dumpprivkey:

bitcoin-cli dumpprivkey 154G5oUywHU3pESNy4oBBpkmAGqRZiYxBk
KzRVLwCuCi2tH2PpSNZnwUqPwg6gaqXAM2LWobUurzAsNdC5JesE

How do I get it in hex in the right format?


texts: Do you have to download the entire bitcoin blockchain for bitcoin core pruned mode to take effect?

texts: I've read that you need to download the entire bitcoin blockchain before you can set it to bitcoin core pruned mode to reduce space. But what if I don't have 100gb+ free on my hard drive? Is there a "pruned" blockchain file I can just download so I can skip needing to downloading the entire blockchain?


texts: What compatibility issues might be expected when using the MegaCoin wallet on Wine?

texts:
Installing a wallet under linux is sometimes difficult without an up-to-date tutorial for users who are not familiar with linux.

I found that it is pretty easy to install wine on Ubuntu 12.04.4 instead and then installing the windows wallet.

I have been using this approach for Megacoin, Darkcoin, and Dogecoin for a month now and have not met any issues so far.

I am still wondering, whether one should expect negative consequences or compatibility issues when running wallets through wine?


texts: Bitcoin Core Update from 0.13 to 0.15 and still verifying block, descending "new best chain"


texts: New Node User Opening Channels Through Zap

texts:
I recently set up my first node and connected through Zap. I currently have one channel open which is funded on my local side and on the remote side for a small amount. I was told that my node is not public and I cannot find it on 1ml. Does anyone know what I need to fix this?
I used the Strike app to create the remote funding by sending my Strike account some BTC from Zap. Ideally I would like to have a channel with about $500 capacity with the end goal of using Strike to buy BTC. To do this would I send $1000 of BTC to my Zap wallet, fund the channel on the local side with $500 worth, then send the other $500 worth to my Strike account - creating $500 local and remote funding on that channel?
An additional question I have: How do I set up a smaller channel that is fully public and will see activity so I can participate in the network and earn lightning fees?
Appreciate any help.


texts:
Can anyone recommend a domain registrar which will both accept BTC and allow anonymous registrations?

I'm aware of this list:

https://en.bitcoin.it/wiki/Trade#Domain_Name_and_DNS_Hosting

But was looking for recommendations as much as information.


texts:
I'm trying to convert a scriptsig into bytes so that I can better extract R & S values, but when I try and convert, I'm missing some of elements that should be there, like x30 for example.

scriptsig = '473044022015d8e1ba1d7fa0bd065f3da2d91d71d12890ff4d9a655161783504714c8b06a3022007d71d93d79039d73fc47ab9787128b7a6d7449e72688f0cf6dc175cfa90755d0121037ab79af7f21e54e03297fc9447952bfacedc57dcebd802eb19ba75636ad1fd5e'

import binascii
bytes1 = binascii.unhexlify(scriptsig) #doesn't work
bytes2 = scriptsig.decode('base64') #doesn't work

The output:
bytes1
'G0D\x02 \x15\xd8\xe1\xba\x1d\x7f\xa0\xbd\x06_=\xa2\xd9\x1dq\xd1(\x90\xffM\x9aeQax5\x04qL\x8b\x06\xa3\x02 \x07\xd7\x1d\x93\xd7\x909\xd7?\xc4z\xb9xq(\xb7\xa6\xd7D\x9erh\x8f\x0c\xf6\xdc\x17\\\xfa\x90u]\x01!\x03z\xb7\x9a\xf7\xf2\x1eT\xe02\x97\xfc\x94G\x95+\xfa\xce\xdcW\xdc\xeb\xd8\x02\xeb\x19\xbaucj\xd1\xfd^'

bytes2
'\xe3\xbd\xf4\xe3\x8d6\xdbMyw\xc7\xb5m\xad]\xed\xf6\xb4m\xdd:\xe5\xfd\xddkg}\xd5\xde\xf5w]\xbc\xf7G\xdf\xe1\xdfZ\xeb\x9eu\xeb^\xfc\xdf\x9d8\xef^\x1c\xf1\xbd:k}6\xdbM;w\xbd]\xf7w{\xf7M\xfdw\xbd\xdfs\x8e\xdao\xde\xfc\xef]\xbco\xb6\xbaw\xbe8\xf5\xee\xf6\xeb\xcf\x1f\xd1\xc7\xfau\xcd{\xe5\xc7\xda\xf7N\xf9\xe5\xdd5\xdb]7\xed\xa6\xfb\xf5\xa7\xfb\x7fm^\xe7\x87\xb4\xdfo{}\xcfx\xe3\xbfy\xd9\xb7\xdaq\xe7\\\xe7\xb7\\y\xb7|\xd3g\x9b\xd7\xd6\xda\xef\x9e\xb7\xe9\xa7u}\xde^'

Once I got the right format I was going to use asn1decoder to parse for x30 and then extract R and S


texts: Improvements that could be made to how bitcoin propagates its transactions and blocks?

texts: As of 2018 what are the known improvements that could be made to how bitcoin propagates its transactions and blocks?


texts: Spending own generated unconfirmed change in the v.0.9.0 era

texts:
Reading about spending own generated unconfirmed change some time ago I stumbled upon this reddit thread  that convinced me that doing so is a really bad idea and could prove catastrophic for any business that allows it.

Now in the bitcoin core 0.9.0 release notes there are some fixes regarding the infamous malleability issue (search for text: "Transaction malleability-related fixes").

My question is pretty straightforward:

Is it now safe to spend unconfirmed change generated by my own txs, after the 0.9.0 upgrades?
If not, what is considered to be a safe number of confirmations for this change before I can use it as an input for another tx?


texts: Offline wallet (Electrum) + Trezor not signing transactions

texts:
When I want to make a transaction I follow these steps

Create order in the ONLINE computer
Copy transaction to a USB
Plug USB to OFFLINE computer
Load transaction from file
Plug TREZOR
Sign transaction

But during the signing process an error popups with a message similar to "Unable to connect to servers ". In my opinion it makes no sense, it is supposed to be an offline wallet. There is no need of a server to sign the transaction. ¿Am I wrong?

As far as i know, both computers use the same Electrum version (2.8.3)


texts:
There are many explorers which allows to dissamble a transaction back into opcodes.

But what about scripts which aren’t broadcasted yet like this redeem script :512102974ffd58d960908d6f2930fbcc4aa288580d05b35a70869e9a8ada3d080acf392103ef884166c7bd20324fd7f959dc680989a6a8b0d62c348defa900fcd4d31200f152ae ?


texts: Is it possible to mine using Asics on AWS?

texts: As title says, I would like to know if mining with asics on aws is possible and how to do it? I don't mean profit because I don't really care and only do it for fun. Thanks!


texts:
How are fees charged when I initiate a trade?

Are they subtracted from my order's volume? Are the fees applied separately from my account's balance? Can I set the currency I want my fees to be charged in?

I have provided the Answer below, including the information given in a support ticket I sent to Kraken Support.


texts: How does OpenBazaar differ from NXT decentralized marketplace?

texts:
I'm contemplating if I should use openbazaar or the nxt marketplace. both a decentralized, but I have a few questions regarding openbazaar:

What incentive does hosting a openbazaar node give? I understand that the nxt marketplace is built into the coin's blockchain so there's the incentive of mining coins while it also hosts the marketplace.
How does openbazaar / nxt marketplace handle fees? Or is there any fees at all? There has to be some sort of fee I'd imagine or else there would be alot of spam.
Can you upload images/pics to openbazaar/nxt ? How do they handle the bloat?
How does user ratings work?


texts: Are there statistics on how Bitcoin holdings are spread among addresses?

texts:
I'm aware an address can belong to multiple people, and one person can have multiple addresses. Still, I'd like to assume the number of accounts per person is O(1) on average.
Are there statistics on how much the bitcoin holdings are spread between different addresses - in other words, on whether a few addresses hold a large portion of the bitcoins, or rather is it spreading out slowly?
Ideally I'd like to see a graph of this "measure of spread" over time.
Related Questions
Is it possible to estimate the Gini coefficient for Bitcoins and if the trend is increasing or decreasing?


texts: BIP deterministic seeds, number of words and compatible wallets

texts:
I like to have a list of Bitcoin wallets that accepts various types of deterministic seeds. I have read that some seeds can not be imported in e.g. Electrum of other.
So a list with following columns would be ideal for me:
BIP type | word count | compatible wallets

Can someone assist me here please?


texts: Bitcoin Address Workflow on Spend Leftovers

texts:
I need to understand the correct Bitcoin address workflow for transactions. I created an address a while back with a common wallet and sent some coin there. The address is at segwit m/49'/0'/0'/0/0. I then spent some coin from that. When I looked up the address on the blockchain, I noticed that the balance was 0. The transaction that occurred had two output addresses. The funds were sent to two addresses. The second is the non-segwit address of the person of who I sent the funds to. The first was segwit m/49'/0'/0'/1/0 (address from my wallet). It appears that the wallet moved my funds to a new address in my wallet. I.e. m/49'/0'/0'/0/0 -> m/49'/0'/0'/1/0.

Should a wallet always move the left over from m/49'/0'/0'/0/x to m/49'/0'/0'/x/0? Is this logic standard practice? Or is this specific to the wallet I used? Is there a recommended practice? I need to know because I am developing a wallet, and I need to follow standard practice.

What should happen when I transfer the funds from m/49'/0'/0'/x/0 to another address, and there are leftovers? Where should the new address for the leftovers be moved to? m/49'/0'/x'/0/0?


texts: Is it possible to create smart contracts on Graphene?

texts:
I can't found any article on this, is it possible to create smart contracts inside the BitShares' blockchain Graphene?

This is my necessity:

I have to allow my users to purchase my products via SmartCoins.
Users must wait for a confirmation (bank signature needed)
Issuance of certificate of ownership


texts: How many throws of a dice are necessary to defeat a brute force attack?

texts:
At bitaddress.org I have decided to use "Brain Wallet" and create my own physical randomness using dice. (I understand that dice are more effective than entering dozens of random keys on the keyboard.)

How many throws are necessary to create a passphrase which would defeat a brute force attack on my keys?


texts: I just launched a bep20 clone, but transactions looks confusing

texts: I have made a clone but my transactions does not read the same way as the original contract that I cloned from. Every sell transactions is divided into 3 sections, and it shows 8 tokens being transferred. How can I make this look like any other normal transaction?


texts: which address do I use to receive and which one to transact and sell/trade?

texts:
in localbitcoins we have address to receive bitcoins.

In Coinbase we can create multiple addresses for bitcoin.

Now which one do I use to receive and which one to transact and sell/trade?

because the address in localbitcoins is shown as invalid at some free bitcoin generation sites/ while the coinbase addresses work


texts: When a node receives a transaction, what steps does it do to verify that transaction?

texts: I know that it verifies the block hash by calculating each hash of the contiguous blocks in order, but does it verify the balance of each wallet sending the transactions as well? And does it do the block hash calculation every time, or does it just do it when it starts up?


texts: Where's the bug in this unsigned transaction?

texts:
When I apply the JSON-RPC method decoderawtransaction to this unsigned transaction it returns {"result":null,"error":{"code":-22,"message":"TX decode failed"},"id":"t0"}:

01000000
02
0f7404441d85118286dbb8e2937fad174d76b834b91705e7fb6b42d57cbe54d3 01000000
14 23376070c7b24da64b435c71613053800494ab1c ffffffff
d6d62745bb4d15d3ef8ff1aaecef5bc7a794e77f3257516edd3ebe5ada659ae4 01000000
14 23376070c7b24da64b435c71613053800494ab1c ffffffff
02
40420f0000000000
1a 76 a9 c8a73488183dd49f63a11dea0a3b242ae70942d2 88 ac
10ae220100000000
1a 76 a9 23376070c7b24da64b435c71613053800494ab1c 88 ac
00000000
01000000

I removed the whitespace characters before sending it.

Here's the transaction in a more friendly format:

{
 :version=>1,
 :in_counter=>2,
 :inputs=>
  [
   {:previousTx=>
     "0f7404441d85118286dbb8e2937fad174d76b834b91705e7fb6b42d57cbe54d3",
    :index=>1,
    :scriptLength=>20,
    :scriptSig=>"23376070c7b24da64b435c71613053800494ab1c",
    :sequence_no=>"ffffffff"},
   {:previousTx=>
     "d6d62745bb4d15d3ef8ff1aaecef5bc7a794e77f3257516edd3ebe5ada659ae4",
    :index=>1,
    :scriptLength=>20,
    :scriptSig=>"23376070c7b24da64b435c71613053800494ab1c",
    :sequence_no=>"ffffffff"}
   ],
 :out_counter=>2,
 :outputs=>
  [
    {:value=>0.01,
    :scriptPubKey=>
     "OP_DUP OP_HASH160 c8a73488183dd49f63a11dea0a3b242ae70942d2 OP_EQUALVERIFY OP_CHECKSIG "},
   {:value=>0.1905,
    :scriptPubKey=>
     "OP_DUP OP_HASH160 23376070c7b24da64b435c71613053800494ab1c OP_EQUALVERIFY OP_CHECKSIG "}
 ],
 :lock_time=>0,
 :hash_code_type=>"01000000"}

Here is the Blockchain.info page for the sender address.

Are there any obvious errors in the friendly format? Or did I make a mistake converting it to hex?

Is there any way to make BitcoinQT provide more informative error messages?

Update: I was able successfully verify another unsigned transaction that I found here:

01000000
01
eccf7e3034189b851985d871f91384b8ee357cd47c3024736e5676eb2debb3f2
01000000
19
76a914010966776006953d5567439e5e39f86a0d273bee88ac
ffffffff
01
605af40500000000
19
76a914097072524438d003d23a2f23edb65aae1bb3e46988ac
00000000
01000000

The four bytes at the end as well as the script-sigs for the inputs are temporary data required for signing. In the working example above they are also present.


texts: How OP_CHECKSIG knows the source of sig in pay to pubkey hash transaction

texts:
https://en.bitcoin.it/wiki/Script#Standard_Transaction_to_Bitcoin_address_.28pay-to-pubkey-hash.29

The last step of pay to pubkey hash transaction is to check the signature of the previous transaction tx hash  and pubkey .

But how the script interpreter knows the sig is the signature of the previous transition hash, what if the sig is the signature of some other content?


texts: How to build coinbase transaction from bitcoin core?

texts:
I am coding a program that connects to bitcoin-qt as local server. For building the blockheader i need the merkleroot, to build the merkle root, i need the coinbase transaction (which is not provided when connecting directly to bitcoin-qt) i understand that i must use createrawtransaction to build it manullay as below:

createrawtransaction '[{"txid":"00000...000000000000","vout":0}]' '{"BTC ADRESS":6.5}'

My question is: In BTC ADRESS i put any adress that i choose from my bitcoin-qt wallet?

And if i double hash the given hex result returned to me, without adding any other transaction, this can be the merkleroot (with only the coinbase transaction) and use it to build the blockheader?


texts: Why are the results of the Coinish Bitcoin calculate so grim?

texts:
I am currently investing into a new gaming PC with a Radeon HD 7990. According to objective reviews (e.g. ExtremeTech Review) this card outperforms many the competitors on the market, especially when it comes to bitcoin mining.

When I played around with the expert settings of the Coinish Bitcoin calculater, I quickly realized, that even with my cheapest energy provider (~0.1$/KWh) I will not be able to break even, considering the price of the card.

In addition I tried the same calculation with the values of high-end asic devices that I found available online, similar results.

Is this calculator too pessimistic or is it really not possible to expect a solid ROI with high-end hardware (GPU or asic) at the moment (End of 2013).


texts: How to import say 1million bitcoin privkeys in bitcoind / bitcoin-qt?

texts:
I was wondering if there are ways to automate / mass private key import into the bitcoin client. Anyone knows of a command or has a script or an idea to share?

thanks.


texts:
I have a question about the security of digital currencies, however still I have find a clear answer for that. No matter what is the currency, e.g bitcoin, monero, ..., at the end of the day, I have to go to somewhere and change the digital money to physical money. Isn't that?

For example, I have 20 XMR. I need to change that to Dollar. So, I have to tell somebody (a bank or someone else) to take this 20 XMR and give me some money. At this point the identity is revealed.

Specifically, I have to first transfer the digital money to the person in the other side and then take the physical money.

Can someone explain that?


texts: in bitcoin core, how to use Tor for broadcasting new transactions only?

texts:
I have set up a full node with bitcoin core running on the internet.  I have also set up a wallet running on a private machine that communicates to the full node to broadcast new transactions.
To enhance privacy, I plan to enable Tor on the full node.  However, it is not clear to me how to use Tor only for broadcasting new transactions from my wallet.
Many tutorials tell you how to use Tor exclusively for everything.  That is not very good, because it wastes bandwidth, is slow and does not help bitcoin community.
Some other tutorials talk about using both Tor and IPv4/IPv6 at the same time.  However, with this setting it is not clear whether new transactions from my wallet are sent out via IPv4/IPv6 or not.  If they do, then you don't have much privacy after all.
Appreciate any pointers on this.


texts:
I don't know what to do about this transaction it have been send for days now and today i got message saying "Transaction rejected by our node. Reason: Transaction was previously accepted but has been pruned from our database"

tx hash:  414514d02b33b80fefce96669680d3e8e54d656d432958211dc632260b26f239

I don't know what do to about this


texts: In the case of a notice at 0 confirmations, I'm seeing the transaction end up on blockchain.info a lot faster than bitcoind is calling the walletnotify callback - about 10 minutes faster. Is it possible to speed this up?


texts: want to study the Satoshi (bitcoind) code

texts: Is there any blog or document that gives a basic "tour" or "overview" of the Satoshi code?  I could just dive in but it would help to read an introduction first.


texts: How can I calculate the breakeven price for buying and reselling on cryptocurrency exchange?

texts:
Assume that one side of the position will be charged the TAKER fee (0.25%), and the other will be charged the MAKER fee (0.10%).

I have tried using this formula, but when selling at the break even price, the result does not sum to zero.

Marking up the MAKER & TAKER fees:

Break Even Price = Buy Price * 1.0035.


texts: What would UTXO consolidation look like in the public ledger with Schnorr signatures?

texts:
I am excited about the privacy and optimisations involved with moving from ECDSA to Schnorr signatures. One of the privacy improvements, as I understand it, is that you can aggregate signatures so instead of revealing the keys involved in a multisig transaction you would only see one key / signature as an input which is the sum of multiple inputs.

But how would this appear in the UTXO set?

If, for example, I have UTXO-1 and UTXO-2 and wish to consolidate them: when I construct the transaction with Schnorr, would UTXO-1 and -2 'disappear' from the UTXO set and the new aggregate signature just appear as an input?

How would this appear in a block explorer?


texts: I bought BCH from Bitcoin.com and provided an Electrum Wallet Address. The money did not arrive and Simplex, who arranged the transaction, advised that Electrum Wallets are only BTC even though the app does not mention this. Simplex sent me a link comprised of a http address on Bitcoin.com's website and the wallet address I originally provided which takes me to where my BCH is sitting but I do not know how to regain control of it and send it to a new BCH wallet. Bitcoin.com do not respond to emails. Can anyone help?


texts: Is it possible to send BTC out of an exchange account, in order to bypass the private key management system

texts:
Inspired by this other question, I wanted to ask a question related to how the private keys are managed by the different exchanges.

The question is: do any of the exchanges allow the sending of bitcoins to external wallet addresses?

(My reason for asking this is that I was thinking it would allow the user to send bitcoins to an address controlled by himself and then get around the enforced private-key management system.)


texts: Why is Bitcoin better than other cryptocurrency?

texts:
If there too many types of such kind of currency, will them be very cheap?

I have 4 BTC and since the current BTC price waves a lot, I am wondering this.

Thanks,


texts: I’m wondering if Liquid network supports arithmetic operations with integers larger than 32-bits.


texts: help problem to synchronize bitcoin wallet core

texts:
I have about 20 usd trapped in an old version, it is version 0.9.3 of the bitcoin kernel.
I urgently need them to pay a significant debt.
Every time I want to pass them to a stock exchange, the wallet freezes my PC and an error appears to synchronize first someone knows or someone who keeps his wallet synchronized. please, help or any other user that exists in this version, where I can get the bootstrap of utorrent
I try to synchronize it normally it stays stuck a week probe adding nodes and it does not work anymore I do not know what to do
Please help. Bitcoin is all I have left to pay my debts. I lost all my assets.
help I believe in the future with bitcoin I believe in satoshi nakamoto help please


texts: I am new to bitcoin, and GUI miner won't work on slush's server

texts: I am new to using bitcoin, and I don't have any mining hardware, just my computer. I got GUIminer, and set the server to other, and the host name to http://api.bitcoin.cz, port 8332. I entered my username and worker name, and it's now mining (very slowly, as expected) but still mining, however, it says on slush's server that i don't have any active workers and I'm not mining, anybody know what the problem is? I also have 1 stale share, what is that, and how did i get it?


texts: Bitcoin client from command line without blockchain

texts:
Any bitcoin client used on linux plateform to send bitcoin from address to another one without using blockchain or full node like bitcoind ?

Thank you


texts: How do I implement a blind multisig protocol?

texts:
I'd like to implement a 2-of-3 multisig protocol such that:

Three parties generate private keys
The private keys are never physically combined on one system - each private key never leaves its system of origin
X Bitcoins are sent to some combination of these private keys
It takes 2 parties to send the bitcoins to a new address
None of the parties gains any information about the stored bitcoins, in particular the value of X or any related addresses
However, two parties working together can gain complete information.

Motivation: You don't trust yourself to hold your bitcoins, and you want to rely on two of your friends to make it very hard on an attacker to steal your bitcoins (he'd have to compromise all of your systems). Still, you don't want to tell your friends information like how many bitcoins you have and where they are stored.


texts: Where did Bitmain get the "Antminer" name from for all their ASIC miners?

texts: Does anyone by chance know? Can't seem to find this anywhere and this question popped into my head.


texts: Bitcoin Orphan blocks - short question about the "time lag" factor and proof-of-work "size"

texts:
"However, it is possible that two miners produce a block at a similar
  time. This situation occurs because the acceptance of the blocks into
  the blockchain by the nodes of the blockchain network does not happen
  instantaneously.

  This time lag in accepting a block may lead to another miner solving
  for the same exact block. But only the block with the larger size of proof of work gets accepted into the blockchain."

This is the background of how orphans are produced and handled.

Can you please explain in short

1) What is this "time lag" ? I would like to understand (detailed) what happens during this time lag, what are the full nodes exactly doing during this time until they decide to accept the block into the blockchain? Is this maybe the moment where the nodes check for all the bitocin protocol rules (refering to https://en.bitcoin.it/wiki/Protocol_rules)? Or sth else
2) What is the "size of the proof of work" exactly? Is it maybe the number of leading "zeros" in the proof of work hash, or the "nonce" number, or sth else? On which parameter must you look to know which block was the result of a more "complex work"?
3) Above mentioned protocol rules: When exactly are the nodes (or the network) checking for them, at which exact step of the bitcoin transaction/consensus cycle?: Before miners receive the transactions, after miners receive the transactions but before they start to work on the PoW hashing puzzle, or after they solved the puzzle and broadcast the block to the nodes?

Thank you


texts: Law / country specifics to start Ripple Gateway

texts:
There is requirement in https://ripple.com/wiki/Gateway_Integration_Manual
Gateways should comply with the BSA, have AML policies and require KYC information.
As i understand this requirements can be accomplished only by banks, funds or other financial institutes, am i right?
if so, what is the minimum starters level of capital need to make own gateway?