texts: Ripple paper wallet: is "ripplepaperwallet.com" safe?

texts:
I've been reading on the internet and I have found several websites for generating Ripple paper wallets: ripply.eu, bithomp.com, gatehub, etc. I'm not sure if these websites are official Ripple websites and trustworthy for generating paper wallets.

So, I'm wondering whether https://www.ripplepaperwallet.com is an official and trustworthy website for generating wallets.

I'm using Windows 8.1 and the latest version of Google Chrome.


texts: what happens to low-fee or forgotten transactions

texts: If a transaction has a fee that is too low then it is possible for the transaction to either age out of the mempool (14 days) or get removed because the mempool reaches its max size. So what happens to that transaction? At some point the transaction is "forgotten" so the sender has the funds available to him again. But how does this happen? Since each miner has its own version of the mempool, is it possible for the transaction to still be in one miner's mempool but not other miners' mempools? How does the network of miners "decide" that the transaction is forgotten so that the sender now has the funds available to him again? And could that person resend that same transaction or does the sender have to create and send a new transaction?


texts: Found old ?BIP39 phrase - how to restore wallet

texts:
I recently managed to recover what I believe to be a seed phrase for an old bitcoin wallet.  I am, however, unsure what my next steps should be.  Years ago, I used (if I can remember correctly) bitcoin core and armoury to manage my small crypto wallet.
How do I restore my wallet with just the 18 word phrase?
I may be able to find the public address of the wallet in my files somewhere - will this be of any help?
In a similar file to my 18 word phrase, I found a similar (18 word, 5 line) set of 4 character words (jibberish) but that was created at exactly the same time - could this be of any help?
Sorry I am totally stuck here now.
I've tried installing bitcoin core, armoury and electrum, but I do not understand and cannot work my way through the options to try and restore my wallet.
Any help you can provide would be great
Many thanks


texts: hello im hungarian i need help why blockcain stil me unconfirmed 4 day i have problem no can get block hash

texts:
how much days need wait when get confirmed

https://blockchain.info/tx/6bc53b5a388c9de4b5460afb7e1d54d44c2eb2001f879f871056207c6b9b0b39


texts: What does a Bitcoin transaction consist of?

texts:
I gather that 2400 transactions fit into a 1 MB block.
That's 436 bytes per transaction record.
But what's in a transaction record?

Is there a good Powerpoint presentation that describes how Bitcoin transactions work?

Thanks.


texts: Cannot Find Transaction from Blockchain Explorer

texts:
I just withdrew some Bitcoin (BTC) from FreeBitco.in to this address:
1FCFLjBDk3BGbp2vtEPRNLcbGisZRUWfbV
My withdrawal was confirmed by the website an hour agao, and I received an email from FreeBitco.in showing this link to view the transaction.
However, that link does not show any transactions at all. From my experience and all other information available online, FreeBitco.in seems legit. Why cannot I see the transaction from blockchain explorers? Is that because of the recent drop of hash rate?


texts: What pressure prevents alternate currencies from completely diluting bitcoin?

texts:
Looking into LiteCoin a bit makes me wonder: if LiteCoin were to gain transaction, what's stopping a 3rd, 4th, and 5th currency from gaining traction as well? Wouldn't this effectively eliminate bitcoin's ability of being a "deflationary currency" because other equivalent currencies can be created without end?

The mere fact that nothing else has approached the same popularity as Bitcoin leads me to believe that there is some sort of pressure preventing an explosion of multiple digital currencies.

I know there already are several alternate currencies, so why don't they have the effect of diluting bitcoin as I expect they would?


texts: Why must the entire chain be included in calculations if it's already been validated. Why can't the validated portions be archived to save energy?

texts: I'm new to this so don't laugh.  If all of the previous transactions in a blockchain have been validated as authentic, why does the entire chain have to be carried forward in the calculations?  Why can't the validated portions be hashed and archived to save energy costs from handling so much historical data.  When accountants calculate the current years income, they don't go back to when the company started and add up every income and expense item, they just add the current years results to the archived past totals.  What am I missing.


texts: Transaction sent to me stuck in processing status

texts: Money sent to my Bitcoin address has been confirmed, but is still in the processing status. For 2 weeks now. Does this happen often? Is there any action i can take?


texts:
I'm trying to put up a simple system for some penetration tests.
I have an Ubuntu server 16.04.1 with apache2 and bitcoin.
all running "Hiddn service" through tor (and bitcoind proxied 127.0.0.1:9050).
Now, using easybitcoin.php , the apache shows getinfo, send receive, all good.
but using bitcoin-cli nothing works! "couldn't connect to server"..

my bitcoin.conf is:
server=1
listen=1
proxy=127.0.0.1:9050
rpcuser=myuser
rpcpassword=mypassword

Any ideas why bitcoin-cli can't connect?


texts: How do I calculate expected earnings when mining a cryptocurrency?

texts:
If I have access to currency-specific variables/datasets for any cryptocurrency of choice (see below), how would I calculate which cryptocurrency (out of a fixed set of say 3-5 altcoins -- SHA-256 and Scrypt only) would be most profitable to mine at a given time?

Given: difficulty, hash rate (network), block count, block time, block reward, exchange rate, and exchange volume.

To be more specific, I'm wondering what math would go into calculating Expected Earnings/(MH/sec) for each cryptocurrency with this data? I'm not not necessarily asking for something like http://www.coinwarz.com/cryptocurrency/ that takes your own device's hash rate and power consumption:power cost ratio to determine individual profitability, I'm talking about a general calculation where the output is in the units 'Expected Earnings/(MH/sec)'

(I'm not sure how complicated a calculation like this is, so I'm not asking for exact math or anything just where/how to start with a problem like this)


texts: Which MuSig scheme is optimal? Classic MuSig or this new MuSig-DN scheme?

texts: Now we have two competing MuSig schemes which is better? Classic MuSig or MuSig-DN? Which use case(s) might choose classic MuSig over MuSig-DN and vice versa?


texts: I have been mining for over 24 hours @ 97.3 Mhash/s. Shouldn't I have at least obtained .01 bitcoin by now? How do I verify the mining that I am doing is transferring into my Wallet?


texts: Deeper understating of blockchain forks.

texts:
Ive spend the last 8 months digesting everything and I have a lot more to learn. Is it possible to use Dogecoin on Litecoin network without converting  through an exchange? I assumed  you could since their both  Scrypt and one is a fork.

Also,  I’d like to go learn more.  I’ve done G code programming for CNC machines but that’s it .  So much info out there,  What would you recommend for learning the basics.
Thanks


texts: Trying to calculate the strength of a brainwallet created with a custom diceware

texts:
I want to create a brainwallet using a custom diceware since I don't like the original one. Instead of 7776 words it has 46656 because I use 6 dice for each word instead of 5.

So this is what I got so far, please tell me if I made a mistake:

2 ^ (log2(46656) * 5) / (1 * 10^15) / (60 * 60 * 24 * 365) = 7 years

2 ^ (log2(46656) * 5) is the entropy for a brainwallet of 5 words
1 * 10^15 is 1 Phash/s, which is the hashing power I'm assuming for this attacker. I don't even know if this makes sense, because an attacker doesn't need to start over for each brainwallet he wants to crack.
60 * 60 * 24 * 365 represents a year in seconds


texts: Is there a limit to how long a wallet can be offline?

texts:
I have a wallet file I backed up June 2011, and has been offline for over a year now. When I copied it back into where the files are stored with the official client, it says my balance is 0, with no transactions.

Does it take a long time for my balance & transactions to get updated correctly, or is my wallet considered corrupted, and the coins lost forever?


texts: Lightning Node Daemon hangs at "Initializing btcd backed fee estimator"

texts:
I have been trying to connect to my btcd backend on an external server but when I run:

lnd --bitcoin.active \
    --bitcoin.mainnet \
    --debuglevel debug \
    --btcd.rpcuser myuser \
    --btcd.rpcpass mypass \
    --externalip X.X.X.X:xxxx \
    --btcd.rpccert=rpc.cert

I have also tried including --btcd.rpchost=X.X.X.X:xxxx in the command above

I am faced with this output:

2018-07-30 18:04:13.863 [INF] LTND: Version 0.4.2-beta commit=
2018-07-30 18:04:13.863 [INF] LTND: Active chain: Bitcoin (network=mainnet)

Sometimes I would get more output and would be prompted to input the password for my wallet yeilding me an input that looks like this:

2018-07-30 18:31:52.781 [INF] LTND: Version 0.4.2-beta commit=
2018-07-30 18:31:52.781 [INF] LTND: Active chain: Bitcoin (network=mainnet)
2018-07-30 18:31:52.781 [INF] CHDB: Checking for schema update: latest_version=3, db_version=3
2018-07-30 18:31:52.796 [INF] RPCS: password RPC server listening on 127.0.0.1:10009
2018-07-30 18:31:52.796 [INF] RPCS: password gRPC proxy started at 127.0.0.1:8080
2018-07-30 18:31:52.796 [INF] LTND: Waiting for wallet encryption password. Use `lncli create` to create a wallet, `lncli unlock` to unlock an existing wallet, or `lncli changepassword` to change the password of an existing wallet and unlock it.
2018-07-30 18:31:58.391 [INF] LNWL: Opened wallet
2018-07-30 18:31:58.450 [INF] LTND: Primary chain is set to: bitcoin
2018-07-30 18:31:58.453 [INF] LTND: Initializing btcd backed fee estimator

After around 20 minutes the connection would time out and LND would give me this:

unable to create chain control: dial tcp 127.0.0.1:8334: connect: connection refused

I have verified that the credentials in btcd.conf and btcctl.conf on my external server are the same

My server is definitely running because I can call the btcd server with this command:

btcctl -u myuser -P mypass -s X.X.X.X:xxxx getpeerinfo --rpccert=rpc.cert

Also, btcd isn't giving me any authentication errors when I'm trying to connect to it to LND. It probably doesn't even know my daemon exists.

Does anyone know why I can't connect to my server?


texts:
I am a bitcoin newbie. I am testing solo mining (I know it is not financial feasible in general). I installed bitcoind on Debian and it ran okay as far as I could tell. I've experienced a couple of problems. The size of the bitcoin data directory is still growing when I use:

du -ks .bitcoin/

I ran

./bitcoind getinfo

and got information like this:

{
    "version" : 80600,
    "protocolversion" : 70001,
    "walletversion" : 60000,
    "balance" : 0.00000000,
    "blocks" : 225436,
    "timeoffset" : 0,
    "connections" : 9,
    "proxy" : "",
    "difficulty" : 4367876.00084220,
    "testnet" : false,
    "keypoololdest" : 1389424771,
    "keypoolsize" : 103,
    "paytxfee" : 0.00000000,
    "errors" : ""
}

When I ran

./bitcoind getbalance

I got 0.000000000

The problem is sometime,

./bitcoind getinfo

simply freeze and I have to use Ctrl-c to kill it.

Another problem is I cannot connect to bitcoind using

./minerd --url http://127.0.0.1:8332 --userpass username:password

The result I got is:

[2014-01-12 20:54:03] Binding thread 0 to cpu 0
[2014-01-12 20:54:04] Binding thread 1 to cpu 1
[2014-01-12 20:54:05] 2 miner threads started, using SHA256 'c' algorithm.
[2014-01-12 21:01:36] HTTP request failed: The requested URL returned error: 500
[2014-01-12 21:01:36] json_rpc_call failed, retry after 30 seconds
[2014-01-12 21:02:15] HTTP request failed: The requested URL returned error: 500
[2014-01-12 21:02:15] json_rpc_call failed, retry after 30 seconds
[2014-01-12 21:02:56] HTTP request failed: The requested URL returned error: 500
[2014-01-12 21:02:56] json_rpc_call failed, retry after 30 seconds
[2014-01-12 21:03:35] HTTP request failed: The requested URL returned error: 500
[2014-01-12 21:03:35] json_rpc_call failed, retry after 30 seconds

Again, I had to use Ctrl-c.

Any information is appreciated.


texts: How to get the generator G point for any new curve?

texts:
I have this bitcoin curve:

y^2 = x^3 + 7

but the finite field Fp is modified to be:

n=115792089237316195423570985008687907853269984665640564039457584007908834675927

1-What is the G point?

2-how to get the Y coordinate for any X value?

I'm using this C# code to get Y from X
but it works with original bitcoin curve only.

    public BigInteger mod(BigInteger num, BigInteger by) {
        BigInteger res = num % by;
        if (res < 0) { res += by; }
        return res;
    }

    public BigInteger EC_GetY(BigInteger x, bool modIt, BigInteger n) {
        BigInteger n_OVER_FOUR = (n + 1) / 4;
        BigInteger alpha = mod(BigInteger.Pow(x, 3) + 7, n);
        BigInteger beta = BigInteger.ModPow(alpha, n_OVER_FOUR, n);//SqRtN
        BigInteger Y = beta;

        if (!modIt) { return Y; }
        Y = n - beta;
        return Y;
    }


texts: What will happen if all bitcoin nodes are pruned?

texts:
Does Bitcoin handle the case where all nodes are pruned?

How a new node would get the full Blockchain?


texts: Multiple public keys - Total received funds

texts:
If I create a new public key (Bitcoin Address) for every transaction I'm receiving, is there some way to find my total balances of my wallet/private key?

And are there any downsides with creating unique addresses for every transaction?

Just to make it clear. I'm not talking about total balances in the wallet's GUI. I'm asking if there is some way for thirdpart who is watching transactions on blockchain.info to calculate my total balances in the wallet.


texts: How should one manage the Bitcoin blockchain on a Linux laptop with limited storage?

texts:
I want to run Bitcoin-Qt on a laptop that has limited storage (it has an SSD and is used for many purposes that all require a bit of hard drive space). Assuming these hardware limitations, what would be a good way to manage the blockchain?

So, to be clear, I cannot store the blockchain on the laptop and I want to be able to make regular transactions portably on the laptop.


texts:
I've got certain amount of mBTC from a person I don't know well (we've never met in person, although we chat online from time to time), in the form of them giving me the key for getting access to the wallet. They say, it's just a Christmas gift; and I don't see any obvious signs of scam here (they don't ask me to do anything in exchange and say that I don't owe anything).
But I'm still anxious, as in my world people don't give away money like that. I have only basic understanding of Bitcoin. Is it possible, that I'll run into trouble here? Like, if this person got these money through some illegal activities, could the trace lead now to me instead of them? What else should I look into? (besides our local laws regarding using cryptocurrency and paying taxes, I'm looking into it now)


texts: What happens to .blk files on disk when the Bitcoin daemon switches to a longer chain?

texts:
I’m interested in writing a program that will (1) parse the .blk files that my full-node Bitcoin daemon writes to disk and (2) write them to a relational database in an incremental fashion (i.e., keeping tracking of which .blk files I’ve already seen to avoid duplicating work). But it seems that this approach could lead to problems when my Bitcoin daemon says “uh-oh, another chain is bigger than the chain we currently have, let’s switch to it.” Specifically, I could imagine two possibilities:

The Bitcoin daemon goes back into an existing .blk file and deletes the blocks from the old chain. If that’s what happens, my program would need to keep track of the mtime of the .blk files on disk and overwrite the parsed data that was sourced from those .blk files when the mtime changes.
The Bitcoin daemon never modifies “finished” .blk files (i.e., block files other than the latest one that’s currently being written to), but rather knows that some of the blocks inside the .blk files could correspond to rejected blockchains. If this is the case, my program would need to query the daemon for this information and update the destination database appropriately.

Which (if either) of those possibilities is correct?


texts: Recovering Bitcoin / Litcoin wallet with partial PyWallet recovery

texts:
My wallet disappeared over a year ago with 200+ LTC in it, possibly due to me running CCleaner for Mac over my machine (which looks for and deletes .dat files as part of its sweep as far as i can tell). I have made several attempts to locate my wallet including using Photorec and dumping the existing wallet.dat, but to no avail. I am going for one last chance attempt to recover it before giving up and moving on.

I am attempting to use pywallet to recover the wallet from my machine by issuing the following,

sudo ./pywallet.py --datadir=/Users/patrickquinn/Library/Application\ Support/Litecoin/ --recover --recov_size 121.3Gio --recov_device /dev/disk0 --recov_outputdir /Users/patrickquinn/Desktop/Looking --otherversion=48

which returned

Read 121.3 Go in 58.5 minutes

Found 0 possible wallets
Found 0 possible encrypted keys
Found 1640 possible unencrypted keys

and left two files, recovered_wallet_1388812907.dat and pywallet_partial_recovery_1388812907.dat in the specified 'Looking' directory.

Can these unencrypted keys be recovered or am I snookered?


texts:
Obviously for the Bitcoin system to work, we need an information network on a global scale such as the Internet.

I am sorry if this is a stupid question.

What exact information protocol is being used? Obviously something that sits on top of TCP/IP, but what exactly?

It is these first levels of software that on top of TCP/IP that I am interested...


texts:
Blockchaininfo has datahere on the confirmation times for transactions. Unfortunately it is unclear how  they collect the data, nor if one could get similar data from say Namecoin.

I'd like to include that data in a research paper or collect similar data myself. However,  without their methodology, I cannot use their data or  nor can I duplicate the techniques.The trivially obvious solution of sending test transactions and measuring how long they take to be confirmed would seem to offer a rather incomplete picture.


texts: this transaction spends an input which is unconfirmed ~ 2 hours now

texts:
So i've been waiting 2 hours for this;
https://blockchain.info/tx/df1d61ba4248d502bec5ff542c19eee6cbe7c88d607af89ff5ab485ec1f3800f?currency=BTC

I bought something with blockchain wallet via a site that had bitpay and when i sent it said success but its not confirming its been 2 hours now? i


texts: Storing my bitcoins on an offline computer

texts:
I have a mac that I never use, would storing my bitcoins on a wallet on that laptop and then only connecting it to the internet when I am ready to transfer money be safe? Is there any reason not to do this? That way I don't have to worry as much about viruses infecting it and stealing my bit coins?

Also, what happens if I back up a computer, load it onto a new hard-drive, then open up that computer and run it's wallet, then open the original computer and run it's wallet.. now I have two duplicate wallets on two separate computers? Would I get an error from the P2P network or would I have duplicate coins (I'm assuming the second is obviously not the case)


texts: How to generate specific private keys from 12-word backup and wallet address?

texts:
A single seed can lead to billions of addresses. Some wallets are unable to scan and find all used addresses.

Is it a way to infer the private key from 12-word backup and wallet ID / (public key).

It seems the only way to restore my balance is based on private key.


texts:
Should I make a Dogecoin wallet addresses encryption?

If yes, what are the pros and cons and how it is made on linux - Ubuntu 13.10?


texts: How to transfer BTC between paper wallet and an exchange?

texts: I am new to the paper wallet, and have a few questions about how to use it. Concretely， I am following the instructions here (https://walletgenerator.net/) to generate a paper wallet for BTC, but I am wondering 1. How can I transfer BTC back and forth between my paper wallet and the GDAX exchange, and 2. Is there any fee to do such transfer? Thanks!


texts: Is there a central repository of bitcoin conferences?

texts: I currently use CoinDesk to remain abreast on events and conferences. Any other websites I should utilize?


texts: Are there other ways to have more than one address involved in a SINGLE transaction input or a SINGLE transaction output?

texts:
Full question:
Except for the case of multisignature, are there other ways to have more than one address involved in a SINGLE transaction input or a SINGLE transaction output?


texts:
I want to understand Bitcoin data structure. So i try to understand a raw transaction in json format.
When i checked the blockchain.info API documentation, i see that input structure is defined for transactions like this:

"prev_out":
{
    "hash":"a3e2bcc9a5f776112497a32b05f4b9e5b2405ed9",
    "value":"100000000",
    "tx_index":"12554260",
    "n":"2"
},
"script":"76a914641ad5051edd97029a003fe9efb29359fcee409d88ac"

But when I query a transaction from blockchain.info, it seems differently:

"prev_out":
{
    "spent":true,
    "tx_index":8845778,
    "type":0,
    "addr":"1CfD77hupeUvFwBPxZ2fA8iyWmVwQY22oh",
    "value":10212000000,
    "n":1,
    "script":"76a9147fe34b97aeff4ab754770be5c8f12e2e95332fd488ac"
 }

Is there any document that clearly explains these data fields?

My current wonders:

What is the spent field?
There is no hash field at queried transaction, there must be i think?
What is type field?
Which fields are signed? The signature is generated by which fields hash?


texts:
I mine bitcoin testnet blocks and I find some blocks with difficulty 1.

Some examples: I mined these blocks:

Block 1
Block 2

Why must generated coins mature 120 blocks before they can be spent?


texts:
Moneropedia defines "ring signatures" as:

Ring signatures make sure individual transaction outputs on the blockchain can’t be traced. A ring signature is a group of cryptographic signatures with at least one real participant, but there is no way to tell which in the group is the real one as they all appear valid, while the key image prevents double spends. When sending a transaction, you select some random transaction outputs on the blockchain and mix those with your own “real coins”. Mixing of coins is enforced across the network, making all coins “equal”. Because every transaction output has plausible deniability on their state (spent or unspent), there are no fungibility issues with monero
To read how Monero gives you a privacy by default (unlinkability), see stealth addresses.
A group of cryptographic signatures with at least one real participant, but no way to tell which in the group is the real one as they all appear valid.

It sounds like Moreo's ring signatures are basically a way of building mixing right in. So, is Monero effectively the same as Bitcoin+mixers?


texts: Whats the public key required for in a transaction?

texts: In figure 1 of the original paper by satoshi, why include the public key of the next owner in the hash?


texts: Who is for SegWit and who is against? And what is the consensus?

texts:
I am a little lost in the whole political landscape of implementing SegWit, I understand that Bitcoin Core is for SegWit but are the miners against it? If not then who is against it and what is their proposal?

I have tried googling to no avail.


texts: How do I recover an encrypted bitcoin wallet to which I don't know the password?

texts: My husband died recently.  He had a Bitcoin-Qt wallet with some bitcoins.  I don't know the password and the wallet is locked and encrypted.  Is there anyway to regain access to the wallet?


texts: Can a miner just introduce a block full of valid predetermined transactions in the blockchain and get rewarded?

texts:
My question is - let's say a miner has control over a certain number of bitcoin addresses. He creates a block containing small transactions to and fro from these accounts ahead of time in advance and also calculates the golden nonce for that block should it be introduced in the chain in the future.

Can he introduce this block in the chain at a particular instant of time and get the mining reward, considering that he can determine all the variables that would affect nonce calculation in advance. Also my understanding says that this block won't be rejected by other nodes as all the transactions will be valid with proper signatures(the miner controls all those bitcoins and will only try to spend them at that particular instant). What would prevent such a situation from happening? This way miners could make bitcoins for themselves out of thin air. What am I missing here?


texts: Execute multiple transactions atomically on Ripple

texts: I would like to execute two transactions, e.g. one from account A to account B and one from account B to itself, atomically, i.e. either include both transactions in the ledger or none of them. This is easily possible on UTXO based blockchains, like Bitcoin, as we can have multiple inputs in the same transaction. But this is not the case on account-based blockchains, like Ripple. Is it still somehow possible?


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

texts:
I am looking at starting a business that will send and receive a large amount Bitcoins in a semi automated manner using API's. I was wondering what is the best way to do do this in a secure way to limit my exposure to hacking? My initial thoughts are as follows:

1) Clearing Wallet: have a clearing wallet that holds say 10% over my expected daily amount of bitcoins that will be used for sending and receiving bitcoins. Any time this wallet contains more than my 10% configured amount, a bot will move the excess bitcoins to another offline wallet.

This wallet will be backed up on 3 USB drives using double encryption and be hosted at blockchain.info (two factor authentication will be used to access this wallet at blockchain.info)

2) Emergency Paper Wallet: This is a paper wallet and will be used to hold an additional days worth of bitcoins. If for any reason I need to top up my Clearing Wallet this will be used and then discarded. (one time use only)

3) Cold Storage Wallet: This is were the excess coins from my clearing wallet will be forwarded to and keep offline. This wallet will be created using a bootable USB/CD OS to ensure the machine it is created on is not compromised. This wallet will then be used to make a number of Emergency Paper wallets that will be used to top up the clearing wallet if funds are ever running low. (this wallet will only ever be accessed using a fresh bootable OS)

Is this a good way of ensuring I have a low exposure to being hacked or is there a better way of doing this?


texts: A technical question on MBHD gap limit. Afaic the gap limit (GL) is to warn a user to not create a too large gap between the last actively used address and newly (unused) addresses. Now, suppose I'm sharing the same wallet on two different devices (eg. mobile phone and laptop). Both of them will use the same GL. Isn't there a chance that both will start to use the same address at the same time? Suppose that I hit the request payment on both my mobile device and laptop on more or less the same time (within a second). How do they know that they are not using the same address? Is that information maybe shared via MB servers? Or is using the same address on multiple devices not a problem as they are both owned by me anyway


texts: Where can I access a NXT public testnet node?

texts: Was wondering where can I access a public NXT testnet node?


texts: I've been using lightning network daemon (LND). In an effort to have a balanced node with somewhat equal amounts on both side of my channels, I've sometimes opened channels with the command lncli openchannel Xdest_nodeXX local-amt push-amt and specify push-amt to be approximately 50% of the local-amt. Over the last year or so I've opened and subsequently closed numerous channels in this way. This discussion on stackexchange indicates the funds are irretrievably send to the other node and my funds are lost! Is that true?


texts: Are there any well-curated directories of Bitcoin mining hardware manufacturers?


texts: Would a professional ASIC-machine holder eventually become a bank-like character?

texts:
As we know, one of the concepts of Bitcoin is to be "decentralized". When individual miners, even with ASIC miners, become unprofitable, will the system become more centralized to those several superb professional miners?

Would that finally affect the willingness of users to accept Bitcoin and lead to its collapse?


texts: In my country of Norway online gambling is legal, but the banks are not permitted to transfer money to online gambling companies. So all transfers of money to online gambling sites are done thru third party. is it possible to set up a system using bitcoins to allow people to transfer money to and from a online gambling site?


texts: My firewall blocks all ports except 80 and 443.  Are there any pools that accept inbound connections on these ports?


texts: In HD Wallet recovery how does the wallets know which addresses to recover

texts:
I have been reading the BIP32 proposal explaining how HD works but it didn't mention on any point how one wallet in one phone can recover from a simple mnemonic seed.

Does it just try all possible addresses related to that seed's master key by doing the entire blockchain look up for addresses at the same time ? (This seems impractical imo).
Are there standards on the max nth of address to generate from the wallet side ?


texts: How could the Bitcoin protocol be modified so that pruned nodes could still participate in BIP 37 SPV?

texts: According to Jameson Lopp (https://www.coindesk.com/spv-support-billion-bitcoin-users-sizing-scaling-claim/), allowing pruned nodes to advertise that they support BIP 37 would be impossible without "extensive protocol changes." What changes would make this possible?


texts: would 10 x 2TH/s machines give me the possibility to mine solo

texts: Would 10 X 2TH/s machines give me the a heads up on pool mining or go solo mining obviously using different addresses on each machine, or one address prone to redundant work?


texts: sp20 jackson vs Bitmain Antminer S7 for personal bitcoin mining

texts:
Background:
I am thinking about getting some bitcoin mining hardware. I am hoping to make some money (at least what I spent on the hardware), but mainly I am doing it to learn about bitcoin mining.
Specific info:

I live in Seattle. Energy costs are about 13.0 cents per kilowatt hour
I am planning on putting this in a semi-small room in my basement. There is no AC in this room, but I would be happy to invest in it if it is necessary.
I am planning to spend less than $5,000 on this.

My question:
I am considering two different pieces of hardware, and I want to know what you think would be better. Also, I would love to know if the calculations of the website that I am using are accurate.
Scenario one:
I buy 21 SpondoolieTech SP20 Jackson's for $3,999. These should run at 1.3 TH/s, according to this website that means I would make around $452.05 a month - or $5,424 a year.
Scenario two:
I buy 6 Bitmain Antminer S7 for about $2,400. These should run at 4.7 TH/s. According to the above website, they should make around $466 a month - or $5,592 a year.
The obvious choice seems to be the 6 Bitmain Antminer S7. Is this correct? Or is there something that I am overlooking?
Thanks!


texts: Calculate the amount of Primecoin(XPM) mined/created so far

texts:
According to Wikipedia:

http://en.wikipedia.org/wiki/Primecoin

the reward given for finding a block is 999*(difficulty**2). So does that mean that you need historic data on the difficulty in order to calculate how many coins there are?


texts: Question on getaccountaddress, getnewaddress, getAddressesByAccount

texts:
I would like to get some feedback. I am new to the bitcoin development and I don't want to misunderstand something important before I start designing the application. I am working on bitcoin online-store integration. We are planning to show btc payment instructions to customers after order acknowledgment page so that they can send the payment from their private wallets.

We want to create one address per transaction. (take Transaction No = "abc"). My plan:

First call getaddressesbyaccount("abc"). If it returns blank address
list, then call getnewaddress("abc") to create new address for this
order. (Then create QR code and show to customer with expected
amount).
Otherwise, if the getaddressesbyaccount("abc") returns an address,
use that returning address.

This page says "getaccountaddress will return the same address until coins are received on that address; once coins have been received, it will generate and return a new address.".

I am planning not to use this function because if we expect 1 btc from the customer and he sends 0.5 btc, I don't want to create a new address. This is just to keep things simplified (1 address per 1 account). getaddressesbyaccount function returns a list of addressess associated with the account "abc".
I find getaccountaddress redundant for my needs. Is there any benefit to "getaccountaddress" creating new address if the current address has balance on it? Do you see any pitfall with my logic. Your feedback is appreciated.

Thank you,


texts: Why mining pools miners need to choose their difficulty?

texts:
I read this and this.

It said: "The traditional method involves assigning members a work unit comprised of a particular range of nonce, the number that blockchain miners are computing for. Once the pool member completes the work on the assigned range, he places a request for a new work unit to be assigned."

From what I understand, the nonce range is the same for all miners and in order to proof their work, miner need to send the share with the difficulty fixed.

So I don't understand the interest to increase the difficulty for a miner. If he keep the minimum difficulty, why would he reduce his lucks to proof his work with a higher difficulty?


texts: Mining Bitcoins on PC - Experiment, looking for advice or simple instructions

texts:
I am absolutely new to Bitcoin and mining, I know that mining at home using a PC is not worth even the time and takes years to get any income out of it.
The thing is I need to mine at home using a PC for experimental purposes and education, so basically i just want to make something even like 0.0000001 bitcoin, and only bitcoin no other crypto currency.
I downloaded the Bitcoin Core wallet and downloaded all the years transactions to be up to date, where to go from there i have no idea, i found several miners but they are all confusing, I can't even find my address to start using the basic miners, so please could you give me a guide or a step by step instructions on how to proceed please? I need to do this alone not within a group (pool) of miners as most sites suggested.
Thank you


texts: Recently the Bitcoin Friday event was announced. What is it all about?


texts: How can I generate a Dogecoin address from a Litecoin private key?

texts:
I'd like to do the following:

I use dumpprivkey to get the private key from Litecoin wallet.
I import this private key into Dogecoin wallet
Which will generate a new Dogecoin address. Both will share the same private key.

The most related post I found is: What happens if you send Bitcoin to a Litecoin address?

However, when I try to directly import, it will give me  the
error:
{"code":-5,"message":"Invalid private key encoding"}

So now, how can I dump the private key and decode into hex and move the prefix from "L" to "D" and regenerate a WIF for dogecoin?

Is there any existing solution for it?


texts: Is there any altcoin with improvements in blockchain download time?

texts:
Let me introduce my idea.

Given:

sizeof( Blockchain ) = 16Gb
Downloading of one avi film 16GB from the pirate bay ( 5mb/s ) = 2-3 hours
Downloading of bitcoin's blockchain ( 5mb/s ) = 2-3 days
One day = 6 * 24 = 144 blocks.
Drag - cryptography.

Task:

Accelerate boot of fresh client to the torrent speed. Similar to Bootstrap.

As I can see, downloading of blockchain is the same hard as mining, because there is every time recalculation of hash, comparing, checking of signs, etc...

What if client will only download this 144 blocks for a day and one super block with 144 hashs of the last valid blocks, thereafter only compare current wallet's addresses with addresses in this 144 blocks without any calculation of its hash.

Is there any alt-coin with such accelerator?

E.g. this super blocks might be archived into another ultra-block for a month. Than we have similar to sha(sha(text)) cascade shield against bruteforce attack.

Downloading of blockchain should takes at max the same time as downloading of 16GB avi from the pirate bay. Say, 5mb/s internet channel + p2p / 16 Gb = 2, may be 3 hours ( in the no peers case ), but I spent 2 - 3 days, and I see that this is no internet speed reason, it is CPU + harddisk very very hard job.


texts: What can make an unconfirmed transaction (0-conf) an invalid one other than Double-spend?

texts:
It's obvious that inputs that already been spent will make the transaction invalid (pure double-spend scenario), but is there's anything else that could make a tx invalid?

Invalid inputs?
Invalid signature or other data?

For example, if I have a program that manages a wallet (keypairs are exclusively managed by it, and not by any human, and it's source is public) and it sends payments, can the recipient be insured that even 0-conf tx will be eventually valid and processes?


texts: Am I screwed? Transferred USDT from Polinex to USD dollars in Coinbase and now it's gone

texts:
I've seen others post where they transferred their USDT to a bitcoin address and it got lost.  I specifically clicked on my USD instead of BTC and it provided me with an address to send it to.  However, the same thing happened where it says it's pending and only .0000273 getting transferred.  I transferred a decent chunk of change.

So here's where it's interesting, if I going to omnichannel and type in the address where the USDT was sent, it shows the full amount still available.  I know it's there and the omni wallet shows it but it doesn't let me get access to it.  If I try to import a private key and add an address on to my omniwallet, it let's me put in the TXID associated with the transaction but pulls up zero as the balance.

Any ideas or options out there?  I know the amount is still out there but I can't seem to get it.  I've heard something about importing private keys but I don't know how to find it.  Or am I just plain ole screwed and will have to learn my lesson.  Thanks for the help.


texts:
I have an Android backup that I am sure I am using the right password. I have exported the file, and trying to decrypt it with openssl:

openssl enc -d -aes-256-cbc -md md5 -a -in ./backup_carteira_2017

or

openssl enc -d -aes-256-cbc -a -in ./backup_carteira_2017

I fill in the password when prompted and it seems to decrypt as I don't get a "bad decrypt", however the output is not readable at all. Any password different from the right one throws a bad decrypt error.

Am I missing anything here?

The backup has been generated in Jun, 2017, not sure if this matters.

Regards,


texts: Is it possible to use bitcoin as interplanetary money/store of value?

texts:
Let's say humans have finally made a successful colony on Mars, how useful would bitcoin be to transfer value between Earth and Mars?

And if it won't work with the current implementation, what would need to be changed in order for btc to be used interplanetary?

Assume there is no Mars cash or any monetary system, they just decided to use bitcoin for everything. It however has to be on the same blockchain that Earth is using.

Possible problems to consider:

how would mining work? Lets say a miner on Mars and a miner on Earth both solve a block at the same time, because of ~8 minute delay between the two planets who would get the reward and how to deal with such a problem?

NOTE: I will be updating and modifying this questions to make it more concise and to the point.


texts: wallet.dat from 2014 shown as empty with latest client 0.18

texts:
I have bitcoin wallet from 2014. I have saved it encrypted.
Since then I haven't checked it, until now.
I did sync the whole bitcoin block-chain and when copy my wallet.dat and re-scan wit the client, the wallet got shown as empty. My wallet.dat is 88kb.
Bitcon core Client dump of the wallet shows addresses only from 2019 and wallet keys dump from the client returns error.
Any help is appreciated.


texts: any faucet that can give even 1 satoshi of BTC immediately?

texts: Is there any faucet that can give even 1 satoshi of BTC immediately without waiting til you have some amount, and without faucethub account?


texts:
I have read that entire bitcoins received in one transaction have to be spend in other transaction. The actual amount to be transferred is deducted from the total bitcoins and the change is returned back to sender's bitcoin address.

Suppose, David Sends Alice the amount in form of two outputs, output0: 10 bitcoins and output1: 20 bitcoins in the same transaction. Now Alice wants to transfer 5 bitcoin to Eve. Does Alice has to spend entire 30 bitcoins, by transfering 5 to Eve and remaining 25 to herself?

Or can she choose any of the output e.g. output0: 10, transfer 5 bitcoins to Eve and change 5 bitcoins to herself? If this is the case, how is this tracked, as the hash of the David's transaction can be used to spend the output1: 20 bitcoins.


texts: Cache the Bitcoin Datadir to Improve Performance? Increase Bitcoin DB Cache Size?

texts:
Bitcoin is very disk-intensive and that slows it down. It seems to flush data to disk often thus preventing proper caching. With the datadir on a RAMdisk it is much faster.
Is it possible to increase the db cache size or do something else to improve cache performance.
Of course it would be nice to keep the wallet and important data saved but I would not mind the blockchain to be heavily cached.
I'm asking mainly about Windows OS.


texts:
Some people believe that hoarding hurts the Bitcoin economy.
But are they really right?
As long as corresponding goods vendors and services will be here to stay and reinforce people's faith in Bitcoin, hoarded bitcoins simply do not take part in daily business and do not hurt anyone.
Quite the contrary, they will decrease the supply of bitcoins in active circulation, thus increase the demand for bitcoins, and thus raise their over-all value, right?
Update: This question also comes with a premise or insight that Bitcoin "power users" have savings and spendings wallets or similar setups, and that those two forms of wallets will not tend to "compete" with each other so much. The bitcoins in the spendings wallets will rather compete with the fiat money that respective users will use to buy for goods and services. The bitcoins in the savings wallets will rather compete with more traditional forms of assets and investments.


texts:
How come some algorithms are better for GPU mining vs CPU mining?
From what I know (that may be wrong) most Ethereum miners use GPUs?
And bitcoin miners use CPU and ASIC mining?
What are the different algorithms out there Sha256, Scrypt, what others are being used?
And why some are better to mine with GPUs other's with CPU?
If one is to create a new PoW coin isn't there the danger that someone with a lot of ASIC mining power currently for bitcoin can just switch to your network and easily do a 51% attack and bring down your project?
How can one defend against that? Are there any algorithms that are not good to mine on ASICs?
Should a new Proof-of-Work coin use a new algorithm that most popular coins don't use?


texts:
My btc-e account was hacked (or my passwords stolen from my computer). I was able to make screenshots while they were withdrawing my bitcoins. So i have the btc wallet adress where the money went to and I have the ip adress of the thief.
Is there really nothing I can do? Can I find and contact the owner? how?

The ip is: 21211716315

The wallet is: 15M9rP1GshzBfMbqnHL77iqVcvmgbzVa4S


texts: How would advancement in ASIC manufacturing process affect mining?

texts:
What's the expected performance improvement with the advanced ASICs? When advanced semiconductor manufacturing processes provide high hash rates by consuming low power, and older processes makes mass production cheaper, I'd like to know when approximately, newer ASICs will be able to make older ASICs obsolete.

Following is the semiconductor manufacturing process timeline, from wiki.

  45 nm — 2008 32 nm — 2010 22 nm — 2012 14 nm — est. 2015 10 nm — est.
  2017

http://en.m.wikipedia.org/wiki/14_nanometer


texts: how to get realtime new transaction data in nodejs from bitcore

texts:
I want to run a private node, and use it to receive realtime unconfirmed transactions data into my nodejs script.

How do I go about this?


texts: Get available exchange rates of Ripple's built-in exchange

texts:
I'm not hundred percent sure I got the whole principle of Ripple right. But as far as I could understand it is possible to deposit a currency into my ripple account/wallet via a gateway (e.g. USD via snapswap.com) and then send that currency to another wallet/ripple account and get it exchanged automatically.

For example I want to deposit 1 USD via snapswap.com into wallet1 and then send 1 USD worth of EUR to wallet2. This way, the owner of wallet2 receives my payment in EUR.

My first question would be:

Did I get this right, that it is possible to exchange a currency within the ripple network? Or is it that you have to convert your currency before you deposit into your wallet? In my example convert USD to EUR then deposit into wallet1 and send EUR to wallet2.
Is there a way I can see the exchange rates the ripple network can offer my for any currency pair? e.g USD / EUR.
I want to know if there is a way to get the exchange rate at which my USD will be converted to EUR, before I send the USD / EUR to wallet2. Or, do I have to send my money haphazardly?


texts: Which exchanges still accept USD wire transfers? (Oct 2012)

texts: Are there any exchanges left accepting USD wire transfers? I heard mention of sending to Dwolla and then transferring to Intersango, but only for U.S. citizens.


texts: Today's threshold difficulty at 3,9 what would a miner need to go solo

texts: What i am asking is a relative threshold on the minimum Hash rate needed to mine solo, taking into account todays difficulty,could it be an ASIC of 1TH/s or 5TH/s so as to compare with pool mining


texts: How to manage externally created addresses?

texts: In my application the private keys are created and stored on a HSM. When a new private key is created on the HSM, it returns the corresponding public key. With this public key I create a bitcoin address. Since these externally generated addresses are not part of a wallet, I'm unable to get the UTXOs of this address. Now my big questions is: How can I get the UTXOs of this address without importing it into a wallet?


texts: Proving to a title agency a bitcoin transaction occurred?

texts: What is the best way to prove to a title agency that a particular bitcoin transaction has occurred and that the addresses do indeed belong to the parties exchanging the title?


texts: G++ Trouble compiling litecoin on ubuntu server AMD64 (Version 16.04 Xenial)

texts:
I've been trying to compile litecoin for some time but keep getting an area that reads

(/home/User/Downloads/Litecoin/src/leveldb/libleveldb.a: error adding symbols: Malformed archive
collect2: error: ld returned 1 exit status
makefile.unix:193: recipe for target 'Litecoin' failed
make: *** [Litecoin] Error 1)

All help will be greatly appreciated!


texts: Can a blockchain from the future be synchronized today?

texts:
If one or a few computers with blockchains from a future time line were connected to the Internet today, what would happen? This other question in Worldbuilding focus on possible consequences, but with this one I am trying to focus on the technical details that would allow or prevent a synchronization to happen. Here are a few sub-questions/ideas I would like to focus on:

Would Bitcoin reject a future blockchain (a.k.a. FBC) immediately?
If a larger number of computers (surpassing any other collective group) with the same FBC connected now at the same time to the Internet, would others be forced to synchronize to that blockchain?
If multiple different FBCs connected, would any of them be synchronized? Which ones and why (furthest or closest to the current time)?
Is it possible to simulate an FBC? (e.g. by creating transactions in a future timestamp and synchronizing them)
In the event of a full synchronization with an FBC would transactions be possible? What would be "new blocks"?

I am new to crypto-currencies and to this SE site, and I only found this question with some resemblances to mine, but if you have suggestions which add further details/examples or improve this question, please let me know.


texts: How does the blockchain know if its block hashes have been tampered?

texts:
I'm dealing with some problems to finally understand how implicit consensus works and I've come across with one question. Suppose the following:
A malicious miner proposes the following block to be included somewhere in the middle of the blockchain. If he just copies the value of the previous block's hash pointer in the new block's header, and recalculates the following blocks hash pointers till the end of the chain, by coping the same header in each block in the original chain, wouldn't this blockchain be as valid as the original, considering that the new hash pointers match with the content of each previous block?
A way of trying to clarifying myself and answering to the question was to think of the implicit consensus. Could it be that the other well-behaving nodes will deny this proposing block by storing a copy of the previous state of the blockchain and comparing the old blockchain with a new one?


texts: What is it about a Trezor that means it can't be infected by malware?

texts:
The Trezor testimonials include that

  TREZOR ... cannot be infected by malware

What is it about a Trezor that means it cannot be infected?


texts: How to calculate the risk-free rate of cryptocurrencies?

texts: For a conference, I need to show the Sharpe ratio's of Bitcoin portfolios using different trading strategies. To calculate the Sharpe ratio, I need Bitcoin's risk-free rate. The risk-free rate for normal stock markets is usually taken from Treasury documents. But cryptocurrencies have no central government and are not affiliated to any country. So how to determine the risk-free rate for, for example, Bitcoin? Is it simply 0?


texts: Representation of coordinates in signature. OpenSSL

texts:
I want to calculate the v-value from the signature obtained using the OpenSSL ECDSA_do_sign function. I found that this value is calculated using the parity of y-coordinate of r. Here I also found that the parity of y is equal to the parity of r. I want to understand whether it depends on the implementation. Can anyone tell exactly how the coordinates x and y are stored inside r in OpenSSL. I can't find it in the code.

edited:
  I understand how v is calculated. My question is how to get the y-coordinate of r in the specific implementation of ECDSA in the OpenSSL library.


texts: How Does Bitcoin Core Client Keep Track of Longest Chain/Strongest PoW Chains?

texts:
Bitcoin Core stores blocks in files in local disk. And it uses LevelDb to form an index on top of block storage to make it faster to retrieve a block (basically a simple key-value pair db). See this for more details.

Also Bitcoin Core stores all the blocks that are not that are not in the main chain in case a fork happens and one of them becomes part of the main chain.

How does Bitcoin Core scan the local storage to find the chaintip of the main chain which have most number of blocks? Does is keep a list of heads in memory? It would be extremely nice if you guys can redirect me to the location in the Bitcoin Core source code that handles that process.


texts: Possible attack vector of BIP32 HD wallet

texts:
I've been reading about BIP32 HD wallet and it's implementation and came across a few questions regarding the possible known "attack" vector of leaked private child keys and known xpub parent key leading to the discovery of the parent private key.
Given the following path of an HD wallet:

m/b/p/c

Where m is the master node derived from a seed, b, p, c being indexed nodes in different depths.

Imagine that a server is watching and creating receiving c addresses from p's xpub. If one of c's node's private key gets leaked and the server gets hacked, thus revealing xpub to the attacker, the attack could now generate p's xpriv and with that, all of c's node's private and public address could be derived by the attacker (hardened c nodes included).

First question: If p was a hardened node, could the attacker still calculate its private key from it's xpub and a child's private key ?

Second question: Could the attacker "climb up" the depth (calculate parent's xpriv) from p all the way over to m after calculating p's xpriv from the leaked c key and p's xpub ? Would a hardened b or p make a difference here ?

Third question: If a private key from c's depth was leaked and the attacker knew m's xpub, could the attacker calculate m's private key or does the exploit only permits calculating the direct parent of a leaked child ?

Bonus question: Could anyone give actual use cases for using one or more hardened nodes in a path ?


texts: Where can one find the Bitcoin Dominance chart index?

texts: Is there a chart where it shows how much market cap is bitcoin compared to the rest?


texts: As the question I asked before, I wanted to make an altcoin. The block height in main.cpp allows you to choose which block gets different rewards. If it does, do txNew.vout[0].nValue =  depend on the first block or the normal block reward


texts: How are paths found in Lightning Network?

texts:
I understand now how multihop payments can work in LN, but how do we discover payment paths in Lightning Network in the first place?  Obviously you'd need to take into account the available capacity of the route, and you'd want to discover the cheapest path.

There shouldn't be a payment channel directory, so would it rely on a peer-based search?


texts:
Seems like the interest to work on sidechains has died in favor of Lightning and Segwit ( I might be wrong about this, that just seems to be the vibe I get from social media and seeing what kind of things people are working on and excited about). There doesn't seem to be much interest in the required soft fork to get side chains working ( See also this question where it was predicted that this would be done in 2016, well now its 2018: Is it likely that side-chain support will be added to Bitcoin? ).

Some Core developers like Peter Todd have also expressed serious concerns about the potential downsides ( https://soundcloud.com/mindtomatter/ltb-e104-tree-chains-with ). There also seems to be political obstacles to enabling side chains because it is not clear what benefit it would give to Bitcoin itself.

The only people seriously interested in getting sidechains to work seems to be RSK project and the Drivechain project.

So what kind of progress/work is being done on sidechains and will sidechains ever see the light of day?


texts:
Running on Ubuntu 18.04, I have built Bitcoin Core from source, but the version is 0.18.99, and I would like to be running 0.18.0. I checked out v0.18.0, and went through the build steps again, yet it is still running 0.18.99.

What do I need to do to run 0.18.0?


texts: How do I recover/use an old wallet from 2011/2012

texts:
I heard about Bitcoin from the Security Now podcast back in 2011 and downloaded and started playing with the Windows client at the time from Bitcoin.org.  I think I updated the client a few times, but never really did anything with Bitcoin.  I did get a few partial Bitcoins from the old FreeBitcoins.appspot.com website and from others.  It looks like the last Bitcoin client I might have ran was v0.8.3 and my wallet is backed up from February 2012.

Can I somehow import this wallet (wallet.dat) into a current Windows client? I gather that the blockchain(s), etc. will need to sync up and it will take a lot of time.  I'm a newbie and haven't stayed involved in Bitcoin over the years.  So, I need a serious point in the right direction.

Thanks in advance for any/all help.

-0.NRG


texts: Does Litecoin have a higher chance of address collision than Bitcoin?

texts:
I assume Litecoin has different rules of generating addresses with Bitcoin, since all Litecoin addresses are 34-characters long which is different than Bitcoin.

Given that the rules for generating addresses are different, does Litecoin have a higher chance of address collision than Bitcoin?


texts: Possible to use BlockChain.info and Bitcoin-QT synced?

texts: I've used both BlockChain.info and Bitcoin-QT. Is it possible to use the same addresses on both? I don't have a incredibly large amount of bitcoins, so I'm not worried about it getting hacked into, however I am worried about it getting corrupt as it will be used in two different wallets. Is it possible for them to get corrupt by doing this? If not, how would I import the key to Bitcoin QT from BlockChain?


texts:
can i customize my address start through getnewaddress?

for example instead the address start with 1asdjIOAWJRA

i write getnewaddress 1xxxx then it continues as it wish

also what's the difference between addresses starting with 1 and addresses starting with 3?

can i choose from bitcoin-cli to get my address starting with 1 or it must be random and can be started by 3 while i dont wish that?

the reason of the need to customized addresses to make sure that it really creates this offline addresses instantly and is not in a hidden database installed while installing the bitcoin-cli


texts: How can I mine Monero or other altcoins using Azure Cloud Services?

texts: Is there any way by which I can mine Monero or other altcoins using Azure Cloud Services.


texts: What is the largest number of blocks a transaction has ever waited for confirmation?

texts:
What is the largest number of blocks a transaction has ever waited before eventual confirmation?

Please exclude:

Transactions with no fee
Transactions delayed because of unconfirmed inputs
Transactions that were signed but never broadcast to the Bitcoin network
Transactions that were never confirmed

Transactions with very low fees and or/are dust amounts acceptable. Please link the txid if available


texts: What are all the payment channels implementations?

texts:
I know the Lightning Network (which Electrum wallet experimentally supports) is an implementation of a payment channel, but Mastering Bitcoin (2nd ed.) ch. 12, § "Routed Payment Channels (Lightning Network)" says:

The Lightning Network was first described by Joseph Poon and Thadeus Dryja in February 2015, building on the concept of payment channels as proposed and elaborated upon by many others.

What are the "many others"? Is the Elements Project's "pegged sidechains" "building on the concept of payment channels" too?


texts: How do I retrieve the funds on my Core wallet when I can't synchronize the blockchain?

texts: I have about $200 in bitcoin but my wallet (Core) won't synchronize the blockchain (it's been doing this for days) since for some reason it got corrupted (As it tends to do say every other month) and now I'm unable to retrieve my money. I want to transfer it to a lightweight wallet so this won't happen anymore but I don't want to lose the money I have locked in there. How do I transfer this money when I can't synchronize to the current state of the blockchain?


texts: I have bitcoins in Poloniex. How do I get them to CANADIAN dollars?

texts:
Coin base doesn't allow transfer to a CANADA account and Kraken's authentication is down.
it looks like I can get money out of Quadrigacx?? but how do I transfer my bitcoins from Poloniex to Quadrigacx
am I totally off and there is another way? I'm ready to cash out and would like my bitcoin in cash!

Thank you!!


texts: What is the useful work done during the mining of Bitcoin?

texts: What is the work that the computer performs while it does Bitcoin mining? Is it useful work in any case?


texts: Set a public node to auto forge / mine / stake in NXT / Ardor without login via the gui?

texts: Installed nxt/ardor on my public server and would like to have it auto mine / stake with an account. How can this be done without having to login to the gui?


texts:
I want to run my LND instance (again) and have some trouble with connecting to bitcoin's ZMQ.

Here is what I do:

$ bitcoin-cli getblockcount
575704

$ lnd --bitcoin.mainnet --bitcoin.active --debuglevel=debug --bitcoin.node=bitcoind --bitcoind.rpcuser=tepo --bitcoind.rpcpass=**** --bitcoind.zmqpubrawblock=tcp://127.0.0.1:28332 --bitcoind.zmqpubrawtx=8332

after unlocking lnd wallet I get:

2019-05-12 18:33:03.842 [INF] LTND: Version: 0.5.2-99-beta commit=, build=production, logging=default
2019-05-12 18:33:03.842 [INF] LTND: Active chain: Bitcoin (network=mainnet)
2019-05-12 18:33:03.842 [INF] CHDB: Checking for schema update: latest_version=8, db_version=8
2019-05-12 18:33:03.853 [INF] RPCS: password gRPC proxy started at [::]:8080
2019-05-12 18:33:03.853 [INF] RPCS: password RPC server listening on 127.0.0.1:10009
2019-05-12 18:33:03.853 [INF] LTND: Waiting for wallet encryption password. Use `lncli create` to create a wallet, `lncli unlock` to unlock an existing wallet, or `lncli changepassword` to change the password of an existing wallet and unlock it.
2019-05-12 18:33:10.105 [INF] LNWL: Opened wallet
2019-05-12 18:33:10.204 [INF] LTND: Primary chain is set to: bitcoin
unable to create chain control: unable to connect to bitcoind: unable to subscribe for zmq tx events: dial tcp 0.0.32.140:0: connect: invalid argument
2019-05-12 18:33:10.207 [INF] LTND: Shutdown complete
unable to connect to bitcoind: unable to subscribe for zmq tx events: dial tcp 0.0.32.140:0: connect: invalid argument

bitcoin.conf:

server=1
txindex=1
daemon=1
rpcconnect=127.0.0.1
rpcport=8332
rpcuser=tepo
rpcpassword=****
dbcache=1024
rpcallowip=0.0.0.0/0
rpcthreads=4
rpctimeout=300
zmqpubrawblock=tcp://127.0.0.1:28332
zmqpubrawtx=tcp://127.0.0.1:28333

lnd.conf:

Application Options]
debuglevel=info
#debughtlc=true
#listen=0.0.0.0:9735
externalip=188.167.56.214
#rpclisten=0.0.0.0:8332
alias=axon
color=#ff9200
maxpendingchannels=10
restlisten=0.0.0.0:8080

[Bitcoin]
bitcoin.mainnet=1
bitcoin.active=1
bitcoin.node=bitcoind

[Bitcoind]
bitcoind.rpchost=127.0.0.1:8332
bitcoind.rpcuser=tepo
bitcoind.rpcpass=****
bitcoind.zmqpubrawblock=127.0.0.1:28332
bitcoind.zmqpubrawtx=127.0.0.1:28333
#bitcoind.zmqpath=tcp://127.0.0.1:18501

$ ldd /usr/bin/bitcoind | grep -i mq
    libzmq.so.5 => /usr/lib/libzmq.so.5 (0x00007f9ce53c1000)

if I missed something to show you, please tell me.

Help appreciated


texts: Bittrex websockets: How to get the order history?

texts:
Using the Bittrex websockets API I am able to get the summary updates for all markets and also the exchange updates for specific markets.

However, I am not able to receive the order history (as opposed to updates).

The market exchange updates are regularly received after invoking the hub method: "SubscribeToExchangeDeltas".

I am trying to get the order history via invoking the hub method: "QueryExchangeState".

But this does not seem to work and I don't get an error either ... ?

Does anyone have experience with this or has the same problem or knows a nifty trick, please let me know!

The code I am using is like so:

import pprint
from requests import Session  # pip install requests
from signalr import Connection  # pip install signalr-client

def handle_received(*args, **kwargs):

    print('\nreceived')
    print('\nargs:')
    pprint.pprint(args)
    print('\nkwargs:')
    pprint.pprint(kwargs)

def print_error(error):
    print('error: ', error)

def main():
    with Session() as session:
        connection = Connection("https://www.bittrex.com/signalR/", session)
        chat = connection.register_hub('corehub')
        connection.start()

        connection.received += handle_received
        connection.error += print_error

        for market in ["BTC-MEME"]:
            chat.server.invoke('SubscribeToExchangeDeltas', market)
            chat.server.invoke('QueryExchangeState', market)
            pass

        while True:
            connection.wait(1)

if __name__ == "__main__":
    main()


texts: How do LocalBitcoin's merchants prevent volatility risk?

texts: For example, how does a Bitcoin merchant (someone who buys and sells Bitcoin as a business type deal to make commission) prevent the losses induced by the volatility in the market? I.e., say you buy a Bitcoin on an exchange worth $10,000, and then list it on LocalBitcoins, and the price of Bitcoin drops to $9,500 in the mean time. Now your say 2% commission doesn't cover the cost of the price drop. Do traders just eat these losses and par them off as luck, or is there a way to peg their movements so that they are unaffected by this volatility?


texts: I accidentally sent bitcoins twice to the same address

texts:
Accidentally, I have transfered BTC from my one wallet to another twice on the same address. First transaction was successful, but in the second case the BTC got deducted from one of my wallet but not credited into my other wallet.

Help how to get my bitcoins back?


texts: How can I obtain a better understanding of the P2P messages between my full node and its peers?

texts:
I am interested in how my full node interacts with its peers, what messages it exchanges (e.g. gossip about other nodes on the network, transactions, blocks) and why my full node disconnects with certain peers (is it my full node making the decision to disconnect or the peer?).
I know there is an open PR from Troy Giorshev (also covered in this Bitcoin Core PR review club) to make some of this possible to do within Bitcoin Core. What insights will I be able to garner from using this tool? For example will I be able to work out why a peer disconnected (e.g. because it went offline, because my full node was asking for too much information/too demanding, because I sent it transaction(s) it wasn't interested in?) What is possible currently with this PR and what is possible for future improvements of this tool?
(Also will playing around with this tool let me answer this question on falling back unnecessarily on DNS seeds?)


texts: Relationship of R/S signature in between signed message and DER signature

texts:
this time is difficult for me to explain problem i was facing. i realize that R/S signature in DER signature is not match to the 1 in bitcoin signed message? Ok below is my say signed message.

-----BEGIN BITCOIN SIGNED MESSAGE-----
c4ca4238a0b923820dcc509a6f75849b
-----BEGIN SIGNATURE-----
1BxqqjVC29fvCWin4qBuqZhBy4V7Ncdxby
        IPnTEOU713+XclrBrUEfTLeP0A7QIR4lObzQjBjyxGQExPwkalrQK1JOggIWk4xrfWIjHEC0RKGv3vtguDfto0o=
-----END BITCOIN SIGNED MESSAGE-----

my working way is $decoded_content = bin2hex(base64_decode(IPnTEOU713+XclrBrUEfTLeP0A7QIR4lObzQjBjyxGQExPwkalrQK1JOggIWk4xrfWIjHEC0RKGv3vtguDfto0o=))

then i manage to get R/S signature from $decoded_content. after that, i use R/S signature to generate DER signature. I realized that this DER signature is fail in signature verification.

shortly to say,

my program check valid signature using function in https://github.com/tuaris/CryptoCurrencyPHP/blob/master/Wallet.class.php#L225

if another party send me DER signature, how do i convert it into base64_encoded string? so end up i am able to use function i mention just now.

I try alot of methods but no luck, are R/S signature in both signed message and DER signature means to same?

please help


texts: Overview of solo mining with no GUI's and with GUI's, short explanation.

texts:
So I recently have gotten into bitcoins and bitcoin mining am enthralled with the idea of the whole system. I even went out to buy a POS Evga 610 GT to start mining the day I found out about it. (currently at a blazing fast 12.7Mh/s)

I am using electrum, guiminer, under slush's pool and have made something like 3cents (.006 BTC ?) in the past week.

So I plan to, here in the near future, build my PC/mining rig and wanted to start my solo mining career. I am happy to be in a pool but I love the idea of the lottery.

So I was wondering if someone could give me a quick run down of the options for solo mining on a windows machine. Preferably with GUI's such as guiminer and without GUI's.

I have found this guide
http://www.newslobster.com/random/how-to-get-started-using-your-gpu-to-mine-for-bitcoins-on-windows

Which tells you how to get it running but not the methodology and logic behind it. Could someone explain the steps I would need to take pro-grammatically to write my own miner?
Such as

Create transaction
Build a block object
Hash till good hash found or someone else says they found a hash
Repeat

But obviously more indepth. Aslo please forgive me for my current lack of knowledge, still learning!

** I have a good knowledge of the BTC system, its logic, and how it works abstractly but have not gotten into how nodes communicate and keep the network running. Which is what I would like to know.

Here is me learning the calculation process abstractly
https://bitcointalk.org/index.php?topic=143329


texts: Bitcore full node list with Wallet service enabled?

texts:
Is there any Bitcore full node list out there? I wanted that in order to use the Wallet Service while not being dependant on only one server.

edit: quote on their website:

  You should now be able to run your own Wallet Service for your users.
  Now you can have ultimate control over your wallets without trusting
  random SPV nodes on the Internet.

I want just the opposite. If it's possible I want a very long list of bitcore nodes.

edit2: (from comments)

I know bitcore is based on bitcoin core. but I want to know if there's a directory for bitcore nodes running wallet service. nodes can discover each other through p2p protocol but afaik they don't specify, in the bitcore case, which services they are running.

Like the directories for nodes running Electrum protocol. It would be awesome.


texts: Why would a Tx's inputs not be assumed to be owned by a single service?

texts:
From question 3 in a project titled Blockchain: CSI (in what looks like a very cool class, run by University of Virginia!):

  Problem 3. The Heuristic 1 (Section 4.3) used to detemine sets of public addresses owned by the same entity is based on the assumption that all inputs to a bitcoin transaction are controlled by the same entity. According to the paper, “the sender in the transaction must know the private signing key belonging to each public key used as an input, so it is unlikely that the collection of public keys are controlled by multiple entities (as these entities would need to reveal their private keys to each other).” Explain why this is not actually true. (A good answer will consider in more detail what is needed in the unlocking script to spend each input.)

How is this a flawed assumption?


texts:
I use a blockchain wallet, and I tried to transfer some bitcoin from my blockchain wallet to my paxfull wallet, but its been stuck for like 3 days now. I used the recommended fee, I don't know why it takes so long.

Transaction: https://live.blockcypher.com/btc/tx/731f8f345f008a0d5f777bc92752603bf7ef5360d6963efd2a08f8f81de2a634/

Today I looked up the transaction again, and the 'received time' restarted - its only 17 hrs now even though its been three days already. Anyone knows whats up with that?


texts:
I am having a hard time locating the estimated shipping time for the S9 miner. Estimated shipping dates are listed on the website but delivery times by country are not. How long does shipping take to each of the Group of Eight territories?

https://enshop.bitmain.com/product.htm


texts: Bitcoin API - createmultisig - what is redeemScript?

texts: The Bitcoin API call of createmultisig returns two parameters - address and redeemScript. What is the latter used for?


texts: Statement: for an attacker to change history, they must solve computational puzzles at a faster rate than the rest of the participants combined

texts:
I'm new to cryptocurrency and blockchain. I just started reading the textbook Bitcoin and Cryptocurrency Technologies by Narayananm, Bonneau, Felten, Miller and Goldfeder.

The statement in the title is given in the introduction to the book (page 17 in the pre-publication draft for anyone interested)

I'm assuming it is accurate and that it is connected to the architecture of the bitcoin blockchain. However, I don't quite understand why this is the case. Is it because in order to change history you need to change the entire chain up to the block you want to change? And why do you need do be faster than all others combined?

Any explanation would be greatly appreciated!

Edit: Later, on page 33:

  as long as we store the hash pointer at the head of the list in a
  place where the adversary cannot change it, the adversary will be
  unable to change any block without being detected.

Does this mean that if the head pointer is unalterable (the genesis block) the statement is false?


texts: Most efficient way to store Segwit Address in a database

texts:
This is not a duplicate of What is the most efficient way to store bitcoin addresses in a database? but it's the same question except I need a segwit answer.

Let's say I wanted to store every standard BTC address in an SQL database.
The most space efficient way is to extract the HASH160 address by converting to base58 then slicing away the checksum. This will allow you to store a BTC address in 20 bytes.

Until segwit blocks come.

Is there a way to get to the hash160 address from:
bc1q34aq5drpuwy3wgl9lhup9892qp6svr8ldzyy7c

If not, could someone tell me the most space efficient way to store this address in a database?

I have no need to convert it back to original string, but only ensure its identity.

Thank you


texts: How often does a node connect to a random node?

texts:
I'm trying to understand the likelihood that a node would connect to a sybil attacker, and the critical piece to this that I don't understand is: how often does a bitcoin node connect to a random node that might be part of a recently-created fleet of sybil attacker nodes.

A node has a number of ways it finds addresses to connect to. Nodes have some seed addresses (IP and DNS) hard-coded into the software. Nodes that have never connected before will connect to some of those hard coded addresses and request more addresses. Nodes that have connected before will attempt to connect to addresses in its database.

My first question is: for any given outgoing connection, what is the approximate likelihood a node is able to connect to an address in its database vs one from a hardcoded address (which are presumably sources of more "random" addresses)?

My second question is: how often are random addresses added into a node's database, and how often are address entries removed from a node's database?

The larger question I'm trying to get an estimate to is: what is the average minimum age of a peer that a node connects to? By "minimum age" I mean, for any given peer, how long must that peer have been around in the network in order for a node to connect to it with a given method. For example, an address entry in a node's database will at least be as old as the database entry. Also, addresses obtained from the hardcoded DNS seed have some average minimum age.

Does anyone have any information that would illuminate some of these questions?


texts:
I'm trying to parse the file fee_estimates.dat.
What is the format of the binary data inside fee_estimates.dat ?
I didn't find any information about it in the dev documentation of Bitcoin.

This is the result of the hexdump command for the first 10 lines :

0000000 498c 0002 bf84 0002 bf6d 0007 0000 0000
0000010 0000 0000 00be 0000 0000 8f40 0040 0000
0000020 0000 9068 0040 0000 0000 913a 0040 0000
0000030 8000 9216 6740 6666 0666 92fe 2040 eb85
0000040 2051 93f1 2f40 9db2 61ef 94f0 7e40 3261
0000050 66d5 95fc c540 db4c d25f 9715 0240 d977
0000060 5017 983d f640 0abc 9419 9973 cf40 b1ac
0000070 5b80 9ab9 0d40 ba8f 6ce0 9c0f 0140 c3e3
0000080 98b8 9d76 c140 3414 b9f5 9eef 4c40 54f1
0000090 db3a a03d c340 0c63 bfca a10d c040 f368

I tried to read the code of the file fees.cpp but I'm not an C++ expert.

This is my python script :

# version required to estimate fees
version_r = f.read(4)
# actual version of my node
version_c = f.read(4)
# best block parsed ??
nFileBestSeenHeight = f.read(4)
# first block with historical fees data ??
nFileHistoricalFirst = f.read(4)
# best block with historical fees data ??
nFileHistoricalBest = f.read(4)

After parsing (little endian and bitcoin version decoding) I get :

version required: 0.14.99.00
version client: 0.18.01.00
nFileBestSeenHeight: 507757
nFileHistoricalFirst: 0
nFileHistoricalBest: 0

I have tried to parse the next bytes without sucess.
Any ideas ?


texts:
I'm using rpcminer-cuda to have a play around mining some bitcoins.  I have 2 NVidia cards, and I understand this is not ideal for any profitable mining.  I would however like to have them both working at the same time.  Presently the output from rpcminer-cuda when it starts up is:

rpcminer-cuda.exe -url=myurl -user=myuser -password=password

Client will start 1 miner threads
2 CUDA GPU devices found
Setting CUDA device to first device found

How do I make it use both cards at the same time?  Do I need to tell it to start two threads or is there some other commandline switch I need to use?  I've tried adding -gpu=2 but it seems to be ignored.


texts:
I would like to create a cold storage with Glacier protocol but calling create-deposit-data script fails.
Following this tutorial: https://glacierprotocol.org/docs/deposit/generate-cold-storage-data/
Do you have any idea what is wrong the the script / Python?
glacierscript.py create-deposit-data -m 2 -n 4

Kukoda-MacBook-Pro:~ kukodajanos$ python /Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py create-deposit-data -m 2 -n 4
Are you running this on a computer WITHOUT a network connection of any kind? (y/n)?y
Have the wireless cards in this computer been physically removed? (y/n)?y
Are you running on battery power? (y/n)?y
Are you running on an operating system booted from a USB drive? (y/n)?y
Is your screen hidden from view of windows, cameras, and other people? (y/n)?y
Are smartphones and all other nearby devices turned off and in a Faraday bag? (y/n)?y
Traceback (most recent call last):
  File "/Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py", line 871, in <module>
    deposit_interactive(args.m, args.n, args.dice, args.rng)
  File "/Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py", line 635, in deposit_interactive
    ensure_bitcoind_running()
  File "/Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py", line 311, in ensure_bitcoind_running
    bitcoind_call("-daemon", "-connect=0.0.0.0")
  File "/Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py", line 143, in bitcoind_call
    _, retcode, _ = run_subprocess("bitcoind", *args)
  File "/Users/kukodajanos/Downloads/GlacierProtocol-0.94-beta/glacierscript.py", line 108, in run_subprocess
    pipe = subprocess.Popen(cmd_list, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, bufsize=1)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 394, in __init__
    errread, errwrite)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1047, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory


texts: Linking libsecp256k1 as shared library to Bitcoin Core

texts:
I'm not sure if this question is better suited in the context of Autotools, but since it's about Bitcoin Core, I'll try to ask it here.
I am trying to Compile/Link libsecp256k1 as a shared library with Bitcoin Core.
configure.ac is calling configure of libsecp256k1 but just removing "-disable-shared" isn't engough
https://github.com/bitcoin/bitcoin/blob/7ff64311bee570874c4f0dfa18f518552188df08/configure.ac#L1637
And here it looks like it is static compiling.
https://github.com/bitcoin/bitcoin/blob/7ff64311bee570874c4f0dfa18f518552188df08/src/Makefile.am#L61
Could someone point out to me if this is even possible in a simple way and if so how.
Thanks a lot


texts: How does the lightning network solve double spending?

texts:
This is probably obvious to some of you on here, but I'm a beginner. I recently read the lightning network whitepaper and its very unclear to me how the lightning network addresses the double spend problem without broadcasting transactions to the public blockchain. Can someone explain this to me?

To use the example in the white paper, if Alice and Bob are sending BTC back and forth to each other through a secure payments channel, I agree this provides Byzantine fault tolerance in a two-person economy of just Alice and Bob. Moreover, I agree this solves for scaling issues currently present in Bitcoin. My understanding here is that the net result of Alice and Bob's transactions are posted to the network at some later date, which is what solves the bitcoin scaling issue. That said, if the transactions of Alice and Bob are not immediately broadcasted to the network, then why can't either of Alice and Bob double spend with another party, Cindy? Provided that either of Alice and Bob transact with Cindy before the wallet states of Alice and Bob are broadcast via the blockchain, then there is no way for Cindy's wallet to be "aware" of whether Alice / Bob's wallet state has sufficient bitcoin for a transaction with Cindy. For this reason, I don't understand how double spending is avoided and why Cindy can be sure that Alice / Bob aren't cheating Cindy in a transaction.


texts: ETC vs ETH how do I know the difference?

texts: How do I know if Ethereum is ETH or ETC, when the exchange just offers "Ethereum"


texts: Remote node signature for HTLC-success and HTLC-timeout transactions

texts:
According to BOLT #3, when constructing a HTLC output in the version of the local node (both received and offered HTLC), it requires that the payment to the local node is locked with CHECKMULTISIG opcode that requires both localhtlcsig and remotehtlcsig in order to spend it.

As far as what I have seen, nodes do not exchange their htlcsignatures (although we can derive the htlc public keys through basepoint).

So the question: suppose after I receive an HTLC from a node and I successfully pass it to the other nodes, the node that sent the HTLC to me became unresponsive. Now I will need to broadcast my version of the commitment transaction to the Bitcoin blockchain so that I can claim the funds that are locked with the payment_hash (when I receive one). But, in order to spend that output, my witness stack will need to have 0 <remotehtlcsig> <localhtlcsig> <payment_preimage>. Now, if the remote node is offline, how will I get my hands on the remotehtlcsig in order to get back the funds locked in the HTLC?

Just to provide additional details, below is a local node version of the received HTLC output according to BOLT #3

# To remote node with revocation key
OP_DUP OP_HASH160 <RIPEMD160(SHA256(revocationpubkey))> OP_EQUAL
OP_IF
    OP_CHECKSIG
OP_ELSE
    <remote_htlcpubkey> OP_SWAP OP_SIZE 32 OP_EQUAL
    OP_IF
        # To local node via HTLC-success transaction.
        OP_HASH160 <RIPEMD160(payment_hash)> OP_EQUALVERIFY
        2 OP_SWAP <local_htlcpubkey> 2 OP_CHECKMULTISIG
    OP_ELSE
        # To remote node after timeout.
        OP_DROP <cltv_expiry> OP_CHECKLOCKTIMEVERIFY OP_DROP
        OP_CHECKSIG
    OP_ENDIF
OP_ENDIF


texts: How can I install a bitcoin wallet on Kali Linux?

texts: I got Kali Linux installed on my laptop and I want to install a good bitcoin wallet to store my bitcoins offline.As I know,top 5 best bitcoin wallets would be Bitcoin Core (the first offline wallet),Multibit (lightweight),Electrum,Blockchain Wallet and Hive.I would like to know how to install one or more of these,or at least another wallet,but if it's one that I haven't listed,I'd also want some basic information about it and obviously the installation guide.Thanks!


texts: where is the specification for bitcoin block-chain mining?

texts:
1.) Who wrote the rule book and where is it stored?

2.) Is it stored in a block chain?

3.) Who said bitcoin could hard-fork?

4.) What if some bitcoin holders don't want a hard fork?


texts: Is it possible that a virus could be included in the block chain or even spread out to computers as miners are trying to mine?

texts: I'm new to BitCoin and curious about a lot of things about it, and about the mining network. So is it safe for everyone to mine and not get their PC or other machines get hit by a virus if it goes along the transfer of information? How safe are we from this scenario as users?


texts: Error unlocking bitcoin core wallet with JSON RPC

texts:
I can't get bitcoin core wallet to accept my wallet passphrase so I can get my private key out. The password is correct, as I have tried it to send out and it accepts it, but when I try on the debug it will not. Is it because of the way i write it in e.g. walletpassphase(........)600 or is it
<...........>600 or is it some other way? Please help. It has come up with -32601 and parsing JSON and syntax.


texts: Are there any countries which currently block or plan to block Bitcoin? If anyone has enough reputation to edit this, maybe add "censorship" or maybe "freedom" as a tag because i can't.


texts: Suppose, A and B are malicious attackers. Both want to send unlimited fake transactions to each other. I know that the transactions won't be accepted in the blockchain. In fact, they don't want their transactions to be mined. But, is there any way to take a countermeasure against A and B? And, what will be the cost?


texts: How to Bitcoin Core daemon start automatically each time your reboot your computer.?

texts:
In the official document of bitcoin.org, they ask to use an init script instead of cron job, see the init scripts directory in Bitcoin Core’s source tree.

But the link is not working
Bitcoin Core’s source tree

Cron Job option

  @reboot bitcoind -daemon

I wanted to know the init script to restart a daemon


texts: Are high-s ECDSA signatures forbidden in segwit witnesses?

texts:
I must have looked that up five times by now, but did segwit actually forbid high-s ECDSA signatures in witnesses, esp. in standard single-sig constructions such as P2SH-P2WPKH or P2WPKH? Or are high-s signatures still only non-standard even in segwit inputs?
(I'm aware that the transaction malleability problem due to low-s/high-s is mitigated by moving the signature into the witness, that's not my question.)


texts: Creating watch wallet from master public key at command line?

texts:
I know that by electrum -w WALLET_PATH create a usual wallet can be created.  I'm now looking for way to create wallet file from master public key.

Question

Given I have master master public key, e.g. xpub12345...ABCDE, how can I create its watching wallet file?


texts: How do I make my first purchase of cryptocurrency?

texts:
I'd like to get started in cryptocurrency.  Be it Bitcoin, Dogecoin or something else.
I'd like to keep my own wallet and not use a Coinbase type of service.
How do I start?  Who would I send money to?  And how do I know what I get is of real value?


texts: Is there a guide to uninstall bitcoin core ? Installation mess

texts:
Hi i'm wanting to do a full uninstall of bitcoin core and to follow a book that i've recently bought on programming on the bitcoin blockchain.

I've tried removing all the data and running:

sudo systemctl disable bitcoind

however BC still starts on startup and the above command does not work

Failed to disable unit: No such file or directory

My installations are probably a mess i've got the normal bitcoin core install pulled down and running as well as the github project all build and installed also therefore i'm not sure exactly whats running.

Please can someone provide some help.


texts:
Was there ever a stated reason for the giveaway?

Was this in response to the ridiculous criticisms they received such as "centralization" and concentration of wealth?


texts: What stopping miner from altering value in transaction to increase transaction fee?

texts:
I'm learning bitcoin through this book "Mastering Bitcoin, 2nd Edition by Andreas M. Antonopoulos". I'm at Chapter 6 "Transactions".
Here is my doubt:
Example there is node A, received transaction like this below

{
  "version": 1,
  "locktime": 0,
  "vin": [
    {
      "txid": "7957a35fe64f80d234d76d83a2a8f1a0d8149a41d81de548f0a65a8a999f6f18",
      "vout": 0,
      "scriptSig" : "3045022100884d142d86652a3f47ba4746ec719bbfbd040a570b1deccbb6498c75c4ae24cb02204b9f039ff08df09cbe9f6addac960298cad530a863ea8f53982c09db8f6e3813[ALL] 0484ecc0d46f1918b30928fa0e4ed99f16a0fb4fde0735e7ade8416ab9fe423cc5412336376789d172787ec3457eee41c04f4938de5cc17b4a10fa336a8d752adf",
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 0.01500000,
      "scriptPubKey": "OP_DUP OP_HASH160 ab68025513c3dbd2f7b92a94e0581f5d50f654e7 OP_EQUALVERIFY OP_CHECKSIG"
    },
    {
      "value": 0.08450000,
      "scriptPubKey": "OP_DUP OP_HASH160 7f9b1a7fb68d60c536c2fd8aeaa53a8f3cc025a8 OP_EQUALVERIFY OP_CHECKSIG",
    }
  ]
}

So here transaction fee is: 0.0005 ( 0.1(input) - 0.015(vout[0]) - 0.0845(vout[1]) ).

So what if node A that received this transaction altered the transaction like this:

{
      "version": 1,
      "locktime": 0,
      "vin": [
        {
          "txid": "7957a35fe64f80d234d76d83a2a8f1a0d8149a41d81de548f0a65a8a999f6f18",
          "vout": 0,
          "scriptSig" : "3045022100884d142d86652a3f47ba4746ec719bbfbd040a570b1deccbb6498c75c4ae24cb02204b9f039ff08df09cbe9f6addac960298cad530a863ea8f53982c09db8f6e3813[ALL] 0484ecc0d46f1918b30928fa0e4ed99f16a0fb4fde0735e7ade8416ab9fe423cc5412336376789d172787ec3457eee41c04f4938de5cc17b4a10fa336a8d752adf",
          "sequence": 4294967295
        }
      ],
      "vout": [
        {
          "value": 0.01500000,
          "scriptPubKey": "OP_DUP OP_HASH160 ab68025513c3dbd2f7b92a94e0581f5d50f654e7 OP_EQUALVERIFY OP_CHECKSIG"
        },
        {
          "value": 0.07450000,
          "scriptPubKey": "OP_DUP OP_HASH160 7f9b1a7fb68d60c536c2fd8aeaa53a8f3cc025a8 OP_EQUALVERIFY OP_CHECKSIG",
        }
      ]
}

Now the transaction fee is: 0.0105 ( 0.1(input) - 0.015(vout[0]) - 0.0745(vout[1]) )

What If node A after altering the transaction, able to find the nonce and submit the block to the other nodes.

Other nodes trying to validate this block will checks the UTXO set and signature by the owner found it's a valid block and accepts it to the chain.

Sender can't deny because that transaction has his signature.

In the book it's mentioned that transactions can happen in unsecured network, what if someone altered the transaction values in the middle going through this unsecured network like I mentioned above, now every node gets this altered transaction.

My Question, is this possible or there any further checks happen to ensure the transaction values are the valid ones sent by owner. So far what I learned (till Chapter 6) there is no hashing of values or whole transaction just owner signature.


texts: Isn't it safer to only encrypt the wallet, then back it up, and NOT save the seed?

texts:
If you use the seed, and it gets compromised, then you immediately lost all your coins.
But if you only save the password safely, and backup the wallet file in several locations, then you gain a form of multi-factor authentication, because if the password gets compromised - the wallet file is still needed, and vice versa.

The seed may be useful for portability of the wallet, but it's a major security risk compared to just using the password and wallet file.

Am I missing something here?


texts:
I just stared in the bitcoin world and my bitcoin pool says I have :

Bitcoins    0.00000277
Namecoins   0.00000864

What exactly that means Namecoins mean? Is there any extra effort to process those Namecoins?


texts: I know it is currently not possible to cancel transactions in the Bitcoin. However, say someone wants to implement such mechanism in an altcoin. Is it theoretically possible without damaging the open nature of cryptocurrencies ? Do we have the required primitives for it ?


texts: Are the huge transaction fees mostly mistakes or some other market indicator?

texts:
I am trying to understand why there are numerous days in Bitcoin's history that show huge transaction spikes.  See this blockchain.info chart.

The Jan 10th, 2012 spike is due to a mistake by this guy.  I can't explain the other spikes.

Are these spikes mostly or all due to human error? Or are they some other indicator, possibly market value, global usage or popularity?  Maybe some think that paying a high fee is supporting the network.

The number of transactions can obfuscate the actual worldwide usage due to things like mixing services, automated transactions, spam.  Maybe the fees spent can rule those out and show the global adoption rate assuming those types of transactions would avoid fees as much as possible.

Bonus points if you happen to know what specifically caused any one of these individual spikes.  Having a list would benefit Bitcoin history story telling.


texts: How does Bitcoin have an intrinsic value?

texts:
I have read several articles about how Bitcoin have an intrinsic value. Aside from the fact that some of those articles confuse "intrinsic value" with "benefits of adoption", I found that none of them could prove that Bitcoin is actually money and not a currency.

Take this example, if I take my Bitcoin from the US to Yemen, it would be the equivalent of taking absolutely nothing to Yemen. Why is that, you ask?

Because Yemen has no Bitcoin bank/supplier/merchants, no one cares about Bitcoin. Now, if I take Gold to anywhere on Earth, people will take that. In the case of Gold, the supply is limited but the demand is unlimited (everyone accepts it) for two reasons. One reason is that Gold is money in itself (if the country uses Gold standard, which I don't recall any that does), and two, is because even if Gold is not money in the country, it's still a commodity to be sold to get money!

So Gold indeed has a value just for being Gold! Bitcoin is a supply and demand currency, which Bitcoin.org clearly states ("The price of a bitcoin is determined by supply and demand"), yet they also say "Much of the trust in Bitcoin comes from the fact that it requires no trust at all", that's illogical as it's dependent on the demand of people which varies by location, i.e. you need to trust that that place has a Bitcoin bank!

If people of that country don't have Bitcoin bank, then that immediately means that Bitcoin value is almost 0 in that country. If Bitcoin's value is zero, no bank would want to spend money to build a branch there. So it's more like fiat currency!

I wouldn't go very far with a Dollar in the country that doesn't have its currency tied to Dollar (even though I don't recall any that doesn't, except the Islamic State, which recently announced Gold and Silver money). This proves several things, that Bitcoin is a currency, that it's dependent on the demand (specifically the location of the market), and thus, that, very much, takes the "universality" it's so much praised for when people talk about how you can make international transfers so easily. You really can; but the problem is that you probably wouldn't do so to most countries that actually need that capability; due to the nature of those countries and the lack of a Bitcoin bank. The only reason why one might want to get Bitcoin in countries where no Bitcoin bank exists, is to buy stuff online. But then again, this has never been the main problem. Credit Cards have solved this for a long time.

So I guess the question is, does Bitcoin have an intrinsic value (is it money) or does Bitcoin have "location value"/trust value (is it a currency)?


texts: High activity on exchanges vs. low transaction rate on blockchain

texts: I a bit puzzled to see high transaction rates on BTC exchanges yet read that the blockchain only confirms about 6 transactions per second. Given that every transaction on an exchange requires also a transaction on the blockchain, how does it work? Is my perception of the volume just wrong? Or are there quiet times at exchanges when the blockchain can catch up?


texts:
Definition of the word Experiment:

  A scientific procedure undertaken to make a discovery, test a
  hypothesis, or demonstrate a known fact.

If Bitcoin was/is an experiment, I don't think it's trying to make a discovery, it certainly isn't demonstrating a known fact.

It might be more closer to testing an hypothesis like "A digital decentralized form of money is viable". But what exactly is the hypothesis? Where does the test end? Who declares the end of the experiment? The bitcoin foundation? The governments? Forum folk?

As we're nearing the end of 2014 and getting closer to the fifth birthday of Bitcoin, is it still an experiment?

I know that this is a very broad and open ended question. And yet, the argument is popularly used by prominent people from the community. Like Gavin Andresen. Everytime he faces a tough question, this is his response. If we don't know where the experiment began and where it ended or where it will end, then maybe we should not use this as a wildcard answer.


texts: How to check if a program is mining crypto in the background

texts: I noticed a program I recently downloaded cause my CPU usage increase by 30 percent and 80% GPU usage increment in idle state. It is not a GPU intensive program at all. I am worried about it using my computer to mine crypto. Is there a way to check this or find more direct evidences? Thanks!