texts: Who is paying for the running costs of Bitcoin?

texts:
Bitcoin mining will consume around 70TWh for 2020 (~3 nuclear power plants).
As far as I know, electricity is paid using fiat money. If 1 kWh costs 0.1 $, without counting hardware costs, that means that 1 year of mining costs $7 Billion for electricity.
At the moment, the Bitcoin capitalization is around 357 B$.
It follows that 2% (7/357*100) of the capitalization is used by electricity every year!
Who is paying for that (and how can it be sustainable)?

people who invest in Bitcoin using fiat money?
by Bitcoin deflation comparatively to fiat money?
people who lose money when/if Bitcoin goes down?
more generally: Mafia (an expensive laundry is not a problem if it is good)?
or I don't understand enough how Bitcoin works, and that's something else :-) ?


texts:
I'm having an issue getting the local bitcoin client running on a Mac OS X machine.

When installing berkeley-db4, and running the following command (per the README):

brew install https://raw.github.com/mxcl/homebrew/master/Library/Formula/berkeley-db4.rb -–without-java

I then enter the console, and run cd .. and then:

db-4.8.30/dist/configure --prefix=/usr/local/Cellar/berkeley-db4/4.8.30 --mandir=/usr/local/Cellar/berkeley-db4/4.8.30/share/man --enable-cxx

Once that happens, I get a long trace ending in this error. Has anyone run into this?

checking for a BSD-compatible install... /usr/bin/install -c
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables...
checking whether we are cross compiling... configure: error: in `/private/tmp/berkeley-db420160220-8656-19l1688':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details.


texts: If bitcoin is decentralized then who keeps track of computers in network

texts:
I keep hearing that bitcoin is decentralized i.e. no single entity owns it. And each computer which is part of bitcoin network keeps the copy of ledger.

My question is who keeps track of all computers in bitcoin network? For e.g. if a transaction happens, who sends (or broadcasts it) to network so all can keep a copy of it?

Doesn't it make it centralized?


texts: If I were executing a 51% attack, would I be broadcasting my state of the network to nodes?

texts:
In the scenario where an entity has control of greater than 51% of the hash power and wishes to build a longer chain where they double-spend previously confirmed transactions, do they broadcast the chain to the network as they are working on it?

The alternative scenario I see is the entity working on the chain and only broadcasting it to full nodes at the point where it has overtaken what is believed to be the current longest chain. This second scenario would appear to me to be far more damaging to confidence in Bitcoin if it was pulled off. Technically, are both these scenarios possible?


texts: Should earnings in Bitcoin converter to a traditional currency be treated as trading-income or non-trading income for tax purposes?

texts:
Should earnings in Bitcoin converter to a traditional currency be treated as trading income or non-trading income for tax purposes (for example, in Ireland)? Reason for them being considered trading income is that the Bitcoins need to be sold at an exchange like a commodity. On the other hand, a business gains Bitcoin not necessarily through trading them for goods (say, SatoshiDice), so the other option appears viable.

Which approach should be taken into consideration when figuring out taxes?


texts:
I suspect the router in my network prevents the block chain from being sucked into my machine, using the classic way, i.e. bitcoin-qt or bitcoind.

Is there a way of dowloading the testnet block chain?


texts: When you buy bitcoin do you get the private key mailed to you?

texts: I'm very confused about how you get your private key and how you can transfer it.


texts:
Did somebody try to run the bitcoind full node on the Raspberry pi 3 and one or more lnd nodes on one or more Raspberry pi zeros?

My goal is to support multiple LN clients without having to run a full node for each client. Raspberry pi zeros are cheap, storage and bandwidth are not.


texts: Selling btc but avoiding bank payment reversals

texts:
If you sell some btc using a no-kyc p2p exchange, how do you avoid bank transfer payment reversals?

One of the best things about btc is that no one can reverse bitcoin transactions (unless some sort of smart contract is used I guess), however payment reversals are a problem with bank wire transfers.

Suggestions?

Note: Cash in person is not an option in this scenario.


texts: When mining, all my shares are rejected. Why am I not getting any accepted shares?

texts:
This applies for when I mine anything (Litecoins, Dogecoin, etc.) I have a Radeon HD 6670 (mining @ 100 Mh/s according to cgminer) and it isn't overclocked or anything. Kind of puzzled as to why this is happening.

Does anyone know why I am not able to mine successfully?


texts: Difference between "time" and "mediantime" in getblock?

texts:
For bitcoin-cli getblock, what's the difference between "time" and "mediantime"?

If i'm looking for a strictly increasing series of timestamps, is one better to choose than the other?


texts: How can I generate wallet files for multibit or armory?

texts:
I'm considering working on a bitcoin project that will need to generate wallet files.  I'm not looking to create receipt addresses that a customer can send funds to for an existing wallet.  Instead, I need to generate numerous wallet files, each with preferably only 1 payment address, that can be distributed across multiple locations.

Can this easily be done from a daemon command or with an existing API?  If there is an API for this, any language is fine, though I would prefer Python.


texts: Why does Base58 WIF-format of PK have '5' prefix (the standpoint of mathematics)

texts:
I'm trying create raw private keys using the steps:

Take a version of PK (0x80) and concatenate (as prefix)with my pseudo-random 32bytes-array.
Take a calculated checksum (4bytes) and push it to the end of the array.
Encode the result to Base58Check using the algorithm:

code_string = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
x = converted_arrayofbytes_to_big_integer;
output_string = "";
while(x > 0)
{
    (x, remainder) = divide(x, 58); //x becomes the integer part of dividing here
    output_string.append(code_string[remainder])
}
return  output_string.Reverse();

Ok, I have done it, but I can't understand when x  devided into 58 (through the loop) why the last remainder is 4  always (decimal: when the remainder is 4, it use as index of code_string: the last value of output_string is 5 (Base58) therefore)? I assume this's beacause of version's prefix but who can explain it from the standpoint of mathematics?


texts: In what way does Spectre have "weak" liveness?

texts:
In his article The Spectre Protocol, Aviv Zohar, one of Spectre's authors, mentions that Spectre has weak liveness.
Why does he mention that Spectre has "weak" liveness, and how would "strong liveness" differ from that?


texts: Are you considered a money transmitter if your end users sends you their private keys to send funds on their behalf?

texts:
I have a service where the end user sends me their bitcoin private keys and I send it back out to a new address when a condition happens (ex. if the weather is raining).

Is this still considered as a money transmitter in the US or NYC? And how is this different from a bitcoin wallet application like blockchain.info that also has your private keys but you also have it too?


texts: How can I conveniently generate new addresses for my public key?

texts:
I generated a private key using dice, then wrote a script to konvert that private key to its corresponding public key in its secp256k1 elliptic curve format (a 65-byte number beginning with 04).

Now, I read that there is a very large number of different addresses that one can generate from a single private key, so now I'd like to do exactly that: I would like to generate some random addresses, because I would like to use a different address for each transaction to my private key. Are thera already existing script that generate a certain number of addresses from a private/public key, or do any of you have instructions how I could write it myself?

Best regards


texts: How do I double spend using electrum for fix unconfirmed transaction

texts:
I have two Blockchain.com wallets.(Both of them are mine)
Some days ago i did a big mistake.
I sent 1100$ From wallet #1 to wallet #2. (10.0 sat/vB > As you see this is very very low) (TX LINK)
And i sent  that 1100$ to my friend from wallet #2 after the transaction upper immediately. (99.3 sat/vB) (TX LINK)
Because of low fee in first transaction, both transactions have n't confirmed yet.
I asked people to fix these unconfirmed transactions.
They told me use another wallet like Electrum wallet and double spend those unconfirmed transactions.
So i installed Electrum in my windows 7 os.
For double spend using electrum i found this link :
https://steemit.com/bitcoin/@profitgenerator/tutorial-how-to-fix-unconfirmed-transactions
But it seems it has deprecated.
I could n't understand one part of this tutorial :

Re-create the transaction, but this time put a higher fee.
Sign your transaction, and save it to a file, it should end with .txn extension

My questions :

As you know Blockchain.Com has no RBF option. So those two transactions have n't RBF flag.
In this situation can i use double spend with electrum?
How can i create a transaction in offline mode and sign and save it?
I tried it.But after setting fee and click send button electrum tried to broadcast.And i could n't find an option for sign or save transaction with .txn ex.
Would you please share a complete step by step tut about this.
If i double spend first transaction what happen to second unconfirmed one? (I am a bit confused about this)
Should i double spend two unconfirmed transactions with two temp wallets in electrum or double send of first one is enough?


texts: Will an approved Bitcoin-like system replace Bitcoin?

texts:
What is the chance of another Bitcoin-like currency system to replace Bitcoin? Will Bitcoin still coexist with such systems? Will it affect then-current Bitcoin exchange rate?

By Bitcoin-like, I mean, government and banks approved, more privacy, some other means of mining, special purpose (only to buy cars), with different benefits, etc.


texts: If a miner account is in active , possible to get payout in halving automatically? Bcoz my mining account is active, but cannot access. Possible to get my profit in halving ? My wallet is fused with mining. Please give details. Thanking you.


texts:
My wallet is two weeks behind in synchronizing with the net. It sais I have 8 connections with the net, however...
On top of my walletscreen it says: "Warning: Shown transactions are possible incorrect! You might need to upgrade, or other nodes need to upgrade."

How to solve this problem?


texts: Does a new nodes verify all transactions or only blocks

texts: When a node downloads the genesis and all blocks, does it verify all past transactions, or just the blocks (eg check the nonce/hash relation, thereby assuming the containing transactions must be right?)


texts: How to allow/setup crypto transfers/payments on my website?

texts:
I'd like to learn how to allow end users on my website to pay for goods using cryptocurrency.

Questions I have:

1 - How would I confirm the transaction has been received ?
2 - How would I confirm the value of the transaction is correct ?
3 - Are there any API's I could use to achieve what I'm looking for ?
4 - If I had to refund a user how would I do this ?


texts: What is the btc.to address shortening algorithm?

texts: How does the btc.to address shortening algorithm work? Is is a deterministic algorithm, that is, it can be reproduced on other websites with the same results, or are the results specific to the website and the order in which the addresses were inputted?


texts: c# BitcoinLib: GetRawTransaction verbose=1 does not work

texts:
I want to find out confirmation number for non-wallet transaction.

When I use
CoinService.DecodeRawTransaction(CoinService.GetRawTransaction("5bc89f4e7f7fe4bd6bd15b439038e2a50a88c158680814164d3428a73a84daef")) I got transaction details, but without confirmations field.

I assume I should use GetRawTransaction("..", 1) but got exception "There was a problem deserializing the response from the wallet".


texts: What is the longest time gap between blocks in 2010 - 2011?

texts:
I notice on blockexplorer that block 159531 was mined at 2011-12-28 10:53:53 and the next block was mined at 2011-12-28 11:24:58 - a gap of more than half an hour. I know the 10-minutes-per-block rule is just an average that the network tries to maintain, thus outliers are possible. So what's the longest we've had to wait for the next block to be mined, in the last year (2010 to 2011)?

Edit: clarifying that I'm interested in the longest gap between blocks in "recent history", which I arbitrarily define to be the last year.


texts: Why did the remaining money go to another address?

texts:
I'll try to be short.
I gifted 1 BTC to a friend several months ago. She is a completely non-technical person. She tried to send a small fraction of that 1 BTC to her brother, and either she seriously messed something up, or fell a victim to some attack.. I never had a reason to use the Blockchain Explorer, but now that I want to try and figure out what happened to her 1 BTC, this is what I see when looking up her Wallet's address in there:

1) A transaction where I send 1 BTC to her:

{transaction id xxxx}              ===>    16WE..<her address> (Spent)   1 BTC
1HHj..<my address> (N BTC Output)          1HHj.. <my address>(Unspent) N-1 BTC

That's what I've expected to see - I've started with N BTC, spent one, it's now in her wallet, and I got N-1 left.

And here's the 2nd transaction (of the only 2 associated with her wallet):

2)

{transaction id zzzz}               ===>    14vg..<her bro's address> (Unspent ???!)  0.0001 BTC
16WE..<her address> (1 BTC Output)          15Hn..<WTF? who's that?!> (Spent) 0.9999 BTC

Well, F&#@. Whatever they did (I should've looked over her shoulder...), the dude got the fraction of the 1BTC which was intended for him - but why the rest ended up in some wallet other than the originator's (as it happened in (1) above).

I don't she'd unknowingly did the "advanced send" stuff, which does allow multiple target wallets.. but anyway, she's not technical, but she ain't dumb to place some random wallet into the 'To:' box.. and being very new to the whole explorer business, being a little confused, but I want to know what happened. Why her bro's wallet has "Unspent" next to it, unlike in the first transaction, is just one of the questions. Where could the second wallet come from is another, obviously.

Thanks!


texts: Is the Bitcoin network slowly closing down?

texts:
Consider the following graph:

This chart shows the total number of hosts on the network that were connected in the previous 24 hour period. We collect this by listening to Address messages that are broadcast over the network and I got it from bitcoinstatus.rowit.co.uk. This graph and a number of other graphs on that site show significant reduction in the number of hosts on the network.

Does this mean that the Bitcoin network is slowly closing down? I can see that the graph seems to be quite level at the end, but the trend seems to be downwards.

Thank you jim618 for providing me with the link in this answer.


texts:
Is it possible to make block production difficulty not the same for every node, but automatically adjusting to the node's hardware speed?
For example, node A and node B are both trying to solve for their next blocks, node A's hardware speed is twice that of B's. Their client software detect their hardware speeds and adjust the difficulty in such a way that B's next block's difficulty is only half that of A's.
Is this possible?


texts:
Is there a way to configure cgminer to accept valid but nonstandard transactions for mining?

If not, where, theoretically, would be a good place to look if I was interested in mining nonstandard transactions into the blockchain, i.e. what must I modify in what node/client code?

Alternatively, would it be enough to modify a client to relay such transactions to cgminer without modifying the mining package itself? Does cgminer also verify that a transaction is standard?


texts:
Simple question about Mt Gox's terms for "unverified" "level 0" accounts:
See this URL: https://support.mtgox.com/entries/20919111-AML-Account-Statuses

It says that the daily limit for USD "or equivalent" is 1000USD.
And daily limit for bitcoin is 100BTC.

So my question: if current exchange rate is 100USD/BTC, I can withdraw 100BTC from MtGox to my personal wallet in one day, and then exchange the 100BTC in my wallet for 10,000USD at another exchange, potentially, assuming that another exchaneg will offer me 100USD/BTC?

On other words, is the daily limit of 1000USD only for withdrawing directly to USD?  Or does it mean that the equivalent of 1000USD (10BTC) is the limit no matter whether I'm withdrawing USD or coins?


texts: What is the algorithm to create a Bitcoin mining calculator?

texts: I want to know how I can calculate the profit of bitcoin mining in bitcoins. I am interested in the formula that is used by calculators. For example lets say I have 700mh/s hashrate, current difficulty is 908350862,437. The calculator says I will mine 0.00038755 BTC per day. What algorithm is used to calculate these figures?


texts: Wallets that support 40 byte message attachment via OP_RETURN? Desktop / Mobile?

texts:
I see that many new Bitcoin 2.0 apps are making use of the additional OP_RETURN parameter for attaching data. I see that max limit is 40 bytes or roughly 40 characters? My question now regarding OP_RETURN is:

So is it one OP_RETURN parameter for each bitcoin transaction or per each input/output address? If its each transaction, so its safe to say its about .0001 btc to send 40 byte message?
Which desktop / mobile wallets support adding a custom OP_RETURN message? (ex. attach a short url link)
Aside from OP_RETURN message attachment, what other methods are there to attach custom data?


texts: Unconfirmed transaction and expired address help

texts:
I have one unconfirmed transaction and now the expired address. I cannot abandon the transition because the writing is gray, +24h hours have passed (the arrival was expected in 8 hours...) and no command works.
How can i cancel the sending and resend the bitcoins?
Thanks for any help.


texts:
I was under the assumption that the bitcoind server allowed you to query the blockchain and run commands like bitcoind getbalance on any address. I'm finding out that you may query addresses in your wallet. Is this correct?

What is required to query the blockchain with commands like think locally without the need for external API's?

My intention is to use a Perl script to get account balances.


texts: Just received $50 worth of Bitcoin from someone?

texts:
I am not sure who has sent it to me and why but I just received $50 worth of BTC. How do I find out where it came from?

Accepting an anonymous payment may bite me in the behind later on. Is there an option to deny BTC payments?

Something to think about....


texts: Why does Coinjoin need multiple participants to increase privacy?

texts:
Coinjoin is a method that make a transaction with other transaction of
  other parties to hide the link between txin and txout.

In case of this, why we need others transaction? We have many bitcoin address since we are using HD Wallet(BIP32) so I think we don't need to wait other bitcoiner to participate into shuffling for making a transaction. we can just give our address set.

Is there a special reason that enforce to combine mine and others stuff?

Sorry for my English.


texts: Is bitcoin-qt as PPA really secure? How to proof?

texts:
With Bitcoins being that much worth currently, I came to the conclusion of using a unique old computer just for this "use case".

I would like to run Ubuntu with bitcoin-qt (from PPA), but now the paranoia kicks in: what if the client is corrupted? I know that I can check against the MD5/SHsomething, but who guarantees that the client itself is not corrupted due to an error/mistake or even intentionally?

It is said that with PPA, nobody guaratees that the software itself is not corrupted, so I am unsure about transfering quite a lot of money to some software I don't know anything about.


texts: Is it true the genesis block reward can't be spent forever?

texts: Is the genesis block reward forever unspendable?


texts: Does every full node verify every transaction TWO separate times?

texts:
I am building my Bitcoin expertise, and want to verify my understanding on a specific point: at what point(s) do all full nodes verifies a new transaction?

Here is my understanding in a nutshell, please confirm or correct:

[1] Upon receiving each new transaction, every full node fully verifies it before adding the transaction to the its own mempool

[2] Upon receiving each new block, every full node fully verifies each transaction in the block before accepting the block

If the above understanding is correct, then every full node verifies each new transaction TWO TIMES: once when the shiny-new transaction is unconfirmed, and again a few minutes later when the transaction is included in a block.

I recognize the above is somewhat of an abstraction ... is it an ACCURATE abstraction?

Thanks in advance.


texts: How much does an online store that sells in multiple currencies need to know about exchange rates?

texts:
Please take the title with a grain of salt. I couldn't make it short and also implying all that I am about to ask here.

Consider Yen devaluation. Forex traders constantly buy USD and sell JPY, or vice versa, based on news and events in politics and economy, or anticipation of the same.

Devaluation of Yen affects exporters and importers and, while it will have an effect on Japanese consumer, eventually, it is not that people in Japan today buy a sushi for 100 Yen and tomorrow for 102.1 yen, based on movements in USDJPY on Forex.

But what is an online store, that quotes goods both in Bitcoin and, say Ripple (but insert any alternative crypto currency here), to do in this situation? It has to have a fast and reliable access to some exchange current bid and ask and constantly update the prices of goods.

What are, if any, foreseeable solutions to this extra pressure on merchants who accept crypto-currencies?

How does it affect their customers who, implicitly, have to verify quotes in this or that currency in order to possibly get a better deal?


texts: I am wondering how the Bitcoin program makes profit if there are no advertisements or taxes?  How do the owners make money off of this?


texts:
I spent several hours looking for an API, or a documentation that wouldn't be too much complex but this single thing which I was thinking would be a natural question for anyone who wanted to get started with Bitcoin programming doesn't seem to be very documented.

I'm looking for a way to automatically create a Bitcoin wallet online, I want to create an experience similar to this : http://www.bitcoinbymobile.com/ ("Get Started" -> "I don't have a bitcoin Wallet"). They create a bitcoin wallet for the user directly online and give him a bitcoin address : that's exactly what I would like to achieve. However I can't find any documentation on it.

My ultimate goal is to create a wallet online for the user and to let him put money in this wallet using his local currency and his credit card. But considering what I've seen so far, bitcoin exchange automation seems to be a great deal at this time.

To clarify, my whole question is : do you know any good (and ideally easy) way to programmatically create a bitcoin wallet and generate an adresse on a website AND (I realize it's a different question) to fund this account with a credit card. I find that this is the part of using bitcoins that is really missing.

We can't expect people to use bitcoins for retail commerce if there is not an easy way to create a wallet and to fund it rapidly. For now, what I have understood is that people have to create a wallet either by downloading the program or by creating it on a website and then, they have to have to find an other good website to buy bitcoins. The actual system seems to be more oriented to financials who don't mind to do it than to the average customer who will very rarely complicate his life like this.


texts: Getting source address of a Tx message from it's signature script

texts:
I have a simple bitcoin packet which contains TX message.

in a TX message, one of it's Transaction input hex data was like this:

  8b3e6cc50fd114f8f40f4223dcf3150448ffc1dc5587f1ca5de6d65f1972f46101000000232200203fff89bc822618068e248c92163cd1f3d0c4f1c7e71f0baf172f4b31438fb423ffffffff

when i open this pcap file with wireshark, it show's previous output equal to:

  8b3e6cc50fd114f8f40f4223dcf3150448ffc1dc5587f1ca5de6d65f1972f46101000000

after that i see script length which is 0x23(35). so signature script of this packet is equal to:

  2200203fff89bc822618068e248c92163cd1f3d0c4f1c7e71f0baf172f4b31438fb423

.

can anybody explain to me how to extract source address which is generated from signature script in the above?


texts:
I am trying to compile oclvanitygen because I have an Nvidia GTX 1080 that would most likely be helpful for this. I'm using the Windows Subsystem for Linux with Ubuntu 18.04.

I tried this command: gcc oclvanitygen.o oclengine.o pattern.o util.o -o oclvanitygen -ggdb -O3 -Wall -L/usr/lib/x86_64-linux-gnu/ -lpcre -lcrypto -lm -lpthread -l:/usr/lib/x86_64-linux-gnu/libopencl.so.1

It basically says that libopencl.so.1 does not exist. However, I have libnvidia-opencl.so.1, so I try this command: gcc oclvanitygen.o oclengine.o pattern.o util.o -o oclvanitygen -ggdb -O3 -Wall -L/usr/lib/x86_64-linux-gnu/ -lpcre -lcrypto -lm -lpthread -l:/usr/lib/x86_64-linux-gnu/libnvidia-opencl.so.1

Then it says /usr/bin/ld: cannot find -l:/usr/lib/x86_64-linux-gnu/libnvidia-opencl.so.1

So I do a list of x86_64-linux-gnu, and there it is, clear as day. list of x86-64-linux-gnu

How can I compile this correctly? Here is a picture of what happens when I run the command: GCC Command

I have installed the ocl-icd-opencl-dev package, but it does not include libopencl.so.1.

Please tell me if I am doing something wrong. Thanks!


texts: Looking for JS/Node.js code example to sign a transaction (with multiple UTXOs) with only the extended private key

texts:
Is there any Javascript code out there or examples on how to sign a transaction by using the extended-private-key?

What I am essentially looking for is code that will help derive the private key, that I can then use to sign an individual UTXO with.

Thanks in advance!


texts: generating random pair key has standard?

texts: If a crypto wallet generates all pair key between small range for example between 1-100, the risk and possibility of creating the same key is an increase. Generating random pair keys for cryptocurrency has standard? If the answer is No what the solution cryptocurrency for it?


texts: What happens in a small scale blockchain network?

texts:
My main question here is, is this understanding correct or have I misunderstood something? If this question would be better for Reddit then I apologise in advance and I'll move to there. Thanks.

Scenario:

So technically I could download the bitcoin source code and run my own altcoin (let's call it pokercoin) on a network of 5 computers (for me and my 4 geeky friends who wanted to play poker without chips).

If I'm understanding correctly, we would each be running pokercoin source code/qt on our laptops and no other computers would be needed to keep the thing running (or maybe we would need to run something else to ensure the network works, because otherwise there is no other way of the network doing all the IP level stuff? Or do nodes do this and run something other than the bitcoin source code?).

When I make a payment, each of the other 4 computers receives a copy of that transaction, and they all add this to a block of 1 transaction which gets appended to our very short blockchain after 10 minutes (because hypothetically my computer is able to solve in 10 mins).

If 2 of us made a transaction, (the new block to be added has 2 transactions), but the other 3 computers wrote their own block which diverged in truth to my computer and my friend's computer, then this 51 percent attack would beat the previous block to be appended (or is it added only after ANOTHER block is added (because this is now the longest chain).

We all also get new pokercoin for being miners in our own system (or maybe it is only those running different code who get to be miners).

Finally, none of us actually argues over having any money, because we know that 'how much we own' is actually only made up of the network iterating over every transaction that happened in order to calculate our amounts (and this happens every time a new block is made).

We also don't argue over block sizes, because there are 5 of us.


texts: Cannot quickly move Tether out of the exchanges into my wallet compared to other pairs (why)?

texts:
Getting my feet wet trading on a few exchanges (takes forever to get verified BTW) and have persistent problems over the past few months getting Tether out of the exchanges.

My wallet is fine, the Tether website does not show any issues, nothing stated on the exchanges, but I noticed I cannot quickly / readily move my Tether out of the exchanges compared to everything else.

Is there a different mechanism for getting Tether out of the exchanges since it is tied to "real" money at 1-to-1 ratio?

Are the exchanges somehow "sandbagging" the Tether and / or other coin until it is more beneficial for them to complete the transaction?

I know the last part of the question sounds conspiratorial, but look at the price behaviour on each of the Tether-sided paired instruments (USDT-BTC, USDT-anything)...
   Thanks in advance,
                  Gette


texts: Blockchain data indexing: key-value or relational database?

texts: I'm building a hobby project with bitcoin-style data storage: I'm going to write block data into one large file. I need to decide how to represent the file in app's memory. Bitcoin uses key-value storage to associate entity hashes with places in data files where they are stored. If I want to do the same, are there any serious performance differences between key-value and relational databases for such a use-case?


texts: How do I reverse an unconfirmed transaction to the original wallet

texts: Is there an easy to understand step by step guide I can execute to create a double spend and get the unconfirmed transaction reversed back into the original wallet so I can resend it with a higher fee and get it delivered?


texts: Increase transaction fee with Bitcoin Core client fails because of no change output. Why?

texts:
Context

I created a transaction (using the full balance of an output) with the Bitcoin Core Wallet (running as full node). The transaction got into the mempool of major nodes, as expected. I set the fee to what the client recommended for a slow transaction (little more than 9 sat/B) , but these days this turns out to be very low. Given the current state of the mempool at hoenicke this may get confirmation in weeks, if at all.

Increasing the fee fails

I initially, deliberately, set the transaction to "Request Replace-By-Fee", and I want do increase the fee now. I expected to take some part of the "target amount" and use it as fee, leaving the total amount of the transaction the same (still spending the complete output in total)

However, this does not seem to be possible by design. I get a "Fee bump error" saying "Increasing the transaction fee failed (Transaction does not have a change output)".

What to do about it?

Why am I not able to change the target/fee balance of a transaction, and how am I expected to increase the fee at this point?

Transaction Details (as per Request)

Summary
Size    1xx (bytes)
Weight  7xx
Lock Time   Block: 49xxxx

Inputs and Outputs
Total Input 0.01xxxxxx BTC
Total Output    0.01xxxxxx BTC
Fees    0.00001xxx BTC
Fee per byte    9.xxx sat/B
Fee per weight unit 2.xxx sat/WU
Estimated BTC Transacted    0.019xxxxx BTC

Both input and output addresses start with "1"


texts: How will X509-validated payments request work? (AKA "The Payment Protocol")

texts:
I'm looking for an overview and requirements on how this will work... including

Root CA selection (across the platforms)
What does the request look like?
How does the payment "flow" look like?


texts: How will the Bitcoin scalability problem affect every-day users in the future?

texts: I get that this will cause transactions to take an extremely long time to process, but why is this a problem? Credit card transactions take about 1-3 days to process, yet many vendors still accept them. Will everyday stores and sellers not accept Bitcoin if transactions take too long?


texts:
Is there a way to get a list of the latest transactions IDs? I know I can watch incoming transaction almost live on http://blockchain.info, but is there a way to download the last 10.000 transaction IDs?

Thanks for any hints!


texts: Can one send one payment to two private keys through 1 QR code?

texts:
Is it possible to send via one QR code or bitcoin address one payment that can be divided or split by a percentage of my choice to two private key QR codes, individual users, a percentage of the amount deposited on one QR conventionally by only havin to scan one QR.
What I'm looking for is a platform where one QR code allows me as a shopkeeper to price my items and have them sold so as the payments go or are otherwised forwarded for no fee direct to the suppliers as well as myself in one function. So that I don't have to "do the books" at the end of each month, rather,  price my items with one QR code per item and receive the profit as a percentage split or assinged number, wholsale price, of our choice so as to be paid instantly along side the wholesaler plus as many other parties without any interference of our own...
Any ideas one how I can do this or programmers who could do such a thing and are willing to help?


texts:
After installing bitcoin on CentOS/AWS, an error occurs when connecting with cli.

$ bitcoind -daemon -conf=/.bitcoin/bitcoin.conf
Bitcoin server starting
$ bitcoin-cli getbalance
error: Authorization failed: Incorrect rpcuser or rpcpassword

The following is bitcoin.conf.

mainnet = 1
txindex = 1
server = 1
rest = 1
rpcuser = a
rpcpassword = a
rpcport = 8332


texts: How to get xpriv and xpub from keyPair with bitcoinjs-lib

texts:
I have this code:

const bitcoin = require('bitcoinjs-lib');
const keyPair = bitcoin.ECPair.makeRandom({ });

Question: how do I get xpriv and xpub from keyPair


texts: Bitcoin successfully deducted on sender wallet but did not reach receiver wallet

texts:
Here is the wallet address for receiver: 1Gouzjo9Jav1k4AmRoUJJMzidVfnMoSieS.
I had used the Blockchair site to see and track status. Based on the details, account had seen receiving last 21 hours. Also on the picture, there is no check icon on this transaction. I'm referring to 0.026 BTC. Thanks for those who will answer and help track this transaction.


texts: How do fees get processed in bitcoin? (protocol question)

texts: If the fee isn’t written into the ledger, and it’s just the difference between the input transaction amount and the output transaction amount, how does the miner prove he has access in his wallet to the fee amount?


texts: Is there an open source tool to publicly destroy bitcoins?

texts:
Several interesting applications of bitcoins involve a scenario where they are intentionally "destroyed".  Is there an open source tool that can be used to destroy bitcoins?

And if so, is it possible to programmatically verify (via the same tool or another) that the bitcoins have indeed been destroyed?


texts: What is the alternative of Bitcoin-RPC-Client?

texts: I am implementing Bitcoin-RPC-Client for web application but I found bitcoin-RPC-client is better than bitcoinj and what are the advantages and disadvanatges of Bitcoin-RPC-client.


texts:
I would like to scrap data from Bitcoin and mix of alternative cryptocurrencies which are fundamentally like Bitcoin. The data I am looking for are blocks and transactions.

I found a pretty awesome (very old and not maintained) project called MultiCoin: https://bitcointalk.org/index.php?topic=24209.0

I have noticed cool projects such as DNS Seeding which do things like connect to peer nodes simply to request more peer nodes (without transmitting data), but do not seem to transmit transactions or blocks or any other data.

Are there any more modern implementations of this? As the alternate cryptocurrency space grows I would like to get data from a lot of coins without having to consume more resources than strictly necessary.


texts:
I have a private key for a storage bitcoin wallet (there's not much in there I'm just testing methods) but it is in private key form and to import it to my main wallet I need to convert it into WIF.
My 2 questions are, what does the process to convert it involve? (Ie. Am I expected to use the BIP38 password when converting or is that a sign it's a scam?) And secondly are there any safe offline software I can use or shall I try and use Linux commands?
EDIT:
Thanks for the replies. In the end I found this website:
https://iancoleman.io/bitcoin-key-compression/
I saved the webpage and used it offline in a VM with the internet disconnected completely. Before I reconnected the internet I restored the VM to a previously saved state. The key it generated offline worked perfectly when typed into my wallet.
Further question: does that method sound okay regarding the information being available to the net and the fact I inserted my password into the offline page?


texts:
I'm trying to setup private mining pool, took some time to go around lots of stuff but eventually I got stuck.

I have: a miner (locally), pushpool (ext server #1), MPOS - frontend (ext server #2) and a wallet (locally).

The miner CAN see pushpool, pushpool CAN connect to the wallet however MPOS shows there's no miners whatsoever.

I'm not using that stratum-mining but as I heard, it's optional

cgminer was reporting that some block was found and as far as I understand it takes information about current block/diff from the wallet. If miner connects to pushpoold then the link between miner-pushpool-wallet must be appropriate, right?

Thus I have no idea why mpos reports no active miners, JSON result for current stats is {"pool_name":"","hashrate":0,"workers":0,"shares_this_round":0,"last_block":null,"network_hashrate":43631019858}


texts: How to make sure Electrum connects to my private Electrs server and to no other server?

texts:
I want to connect my Electrum wallet app to my private Electrs server in my local LAN which is also reachable via onion. I want to just use this one server, no other server. My ~/.electrum/config is
{
    "alias": "",
    "auto_connect": false,
    "blockchain_preferred_block": {
        "hash": "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f",
        "height": 0
    },
    "check_updates": true,
    "config_version": 3,
    "gui_last_wallet": "/Users/$USER/.electrum/wallets/default_wallet",
    "is_maximized": false,
    "oneserver": false,
    "proxy": "socks5:127.0.0.1:9050::",
    "recently_open": [
        "/Users/$USER/.electrum/wallets/default_wallet"
    ],
    "rpcpassword": "",
    "rpcuser": "",
    "server": "something.onion:50002:s",
    "show_channels_tab": true
}

This seems to work fine in the sense that I am connected. But I have a lot of nodes in my list under the "Network" settings in Electrum. And this is because the oneserver property is set to false. If I try to set it to true in the config manually, Electrum starts and works fine but the config file is reverted to its old state with false in it.
How can I make sure this works?


texts: Do I need to keep updating Armory version and more?

texts:
Do I need to keep updating version of Armory when it notifies me of new version. Just wondering if these are security patches or just some new bells and whistles in new armory versions. Seems like it took me forever to DL Armory and to install a new version every few months seems like a huge pain I run linux so that makes it even more difficult because I have manually uninstall and re-install and my newbie self doesnt' even know how to on linux as there is no automated uninstall or install like windows.

What gives?


texts: Is there a difference between OP_PUSHBYTES and OP_PUSHDATA

texts:
In some documentation about Script we sometimes have to use OP_PUSHBYTESx or OP_PUSHDATAx to indicate that some number of bytes will be an element to read.
They seem to do the same thing so is there a reason they have different names ?


texts: Can I force my wallet to only have news keys, post-encryption?

texts:
Now that v0.4 of the bitcoin client has encryption I've gone ahead and encrypted the keys in my wallet.  But I had previously made backups of my (unencrypted) wallet and those keys are the same keys that are now encrypted.

This gives me a false sense of security.

Is there any way after I've upgraded to v0.4 and encrypted to force all my existing keys to become invalid and then to spend to a new (encrypted) key so that even if an attacker gets ahold of my backup that my coins are safe?


texts: Bitcoin Transaction Generation: Signature Verification Error

texts:
I have the following raw transaction (basic P2PKH) which I am trying to send to the Bitcoin Testnet 3:
010000000147551ba3faa22b5c5ee1a063849f24af0e347dd9e7bcda849716539684beb8c8010000008a4730440220b7bfb52963d1ad6da2ac67f18d52c9d2cd6ac58283319a69dd76d3ee4d9bf7780220260f335d75cfdc95f7dc9eb3d404dde65f59e484fcedaeddd6dabe4ee58ac122014104157cb2fdf61362a10869604fb3db1841b424006d3fa4f52300eec9a7fecc3a615deabef656b081f64115ad91e6c780c68e20c0bfcd4aafdf9f52af685d7910deffffffff01c0c62d00000000001976a91435d263246f0c03b1f62aa814142d2f3a08421a1788ac00000000
Sending Address:
mm6chMVA1WuZBDwp49yXJK9HWBzx96qxZE
Sending Address Private Key:
82295637717710356959985575716131249482690360273799844241244085665208347300813
Receiving Address:
mkRY9Bh6Mt1n5UsEHda9yXmgCpJ4Z1BeXs
On the Blockcypher PushRawTx page (https://live.blockcypher.com/btc/pushtx/) I am getting the following error:
Error validating transaction: Error running script for input 0 referencing c8b8be849653169784dabce7d97d340eaf249f8463a0e15e5c2ba2faa31b5547 at 1: Script was NOT verified successfully..
On the Blockstream PushRawTx page (https://blockstream.info/testnet/tx/push) I am getting the following error:
sendrawtransaction RPC error: {"code":-26,"message":"non-mandatory-script-verify-flag (Non-canonical DER signature) (code 64)"}
It is unclear what is wrong in the transaction but the errors seem to indicate that it lies in the signature (scriptSig).
I have broken down the transaction as follows, it seems that everything is as specified in the standards.
Transaction:

version: 01000000
input count: 01
prev output hash: 47551ba3faa22b5c5ee1a063849f24af0e347dd9e7bcda849716539684beb8c8
prev output index: 01000000
script length: 8a
script sig: 4730440220b7bfb52963d1ad6da2ac67f18d52c9d2cd6ac58283319a69dd76d3ee4d9bf7780220260f335d75cfdc95f7dc9eb3d404dde65f59e484fcedaeddd6dabe4ee58ac122014104157cb2fdf61362a10869604fb3db1841b424006d3fa4f52300eec9a7fecc3a615deabef656b081f64115ad91e6c780c68e20c0bfcd4aafdf9f52af685d7910de
sequence: ffffffff
output count: 01
value: c0c62d0000000000
script length: 19
scriptPubKey: 76a91435d263246f0c03b1f62aa814142d2f3a08421a1788ac
lock time: 00000000

ScriptSig BreakDown:

signature length: 47
sequence: 30
length: 44
integer: 02
length: 20
R: b7bfb52963d1ad6da2ac67f18d52c9d2cd6ac58283319a69dd76d3ee4d9bf778
integer: 02
length: 20
S: 260f335d75cfdc95f7dc9eb3d404dde65f59e484fcedaeddd6dabe4ee58ac122
Sighash: 01
Length: 41
Type: 04
Pubkey X: 157cb2fdf61362a10869604fb3db1841b424006d3fa4f52300eec9a7fecc3a61
Pubkey Y: 5deabef656b081f64115ad91e6c780c68e20c0bfcd4aafdf9f52af685d7910de

scriptPubKey from previous transaction output:

76a9143d36696be89aef91cec3d54b4a1f5fe3a79ca08388ac

What is the error here? Are there any tools which may facilitate finding the root cause?


texts:
I forked bitocin and created a altcoin.

Now I am running a node of it. There are currently 0 blocks because there are no miners. How can I enable mining on bitcoind?

I tried adding gen=1 with config, but it's not mining.

I believe there was a setgenerate true command, but I am not sure how to use it. How can I make my node mine coins?


texts: Does Bitcoin have inherent value if you can fork the project and create a new cryptocurrency easily?

texts:
I like Bitcoin and I like the ideas to create a limited number of bitcoins. However, I see a lot of new crypto-currencies. It seems anyone could fork bitcoin, change something in the algorithm, and release a new crypto-currency.

So I'm afraid that one could create hundreds of new crypto-currencies each day without any value.

Is this a plausible scenario?


texts:
I am a complete noob to PHP. But I just wanted to know how can you use the BlockChain API to get your wallet balance. I tried but could get no result. I do not even know how to print it. Please help. This is my current code :-

    <?php

    $guid="xxxxxxxxx";
    $main_password="xxxxxxxxx";

    $json_url = "https://blockchain.info/merchant/$guid/balance?password=$main_password";

    $json_data = file_get_contents($json_url);

    $json_feed = json_decode($json_data);

    $message = $json_feed->message;

    ?>

And what exactly is the guid? Is it the wallet identifier?


texts: Needing a Private Key in order to receive profits in Blockchain Wallet

texts: I recently made an investment with Forexbitoptions and have made some profits. They have supposedly sent these profits to my Blockchain wallet but say it's not going through as I need a Private key for this. Question I have is do I need a private key for this and if so why would I have to pay for this private key in order to access my profits?


texts: How to get current BTC rate for BRL(real) using php cURL or javascript

texts:
Is there anyway to get current rate of BRL = BTC.

I saw the blockchiain ticker. But the value for BRL currency is not updated
As listed here in preev.
I want to get the

 current 1BTC= how much BRL

Thanks in advance!


texts: why do i lost my bitcoin on blockchain wallet without forgetting private key?

texts: This is the first time to use Blockchain and send my bitcoin into it. But i was sent into private key wallet address and store it. Next day, when i was login my wallet and say wrong password . So i was restarted my password and login private keys . I don't found my btc. I saw that they sent my btc to another address. Why it that?


texts: Possibility of validation of transaction TX id

texts:
I've readed numbers of thread here but non answer to my question. What I want to know if there is a way somehow to validate transactionID ( txID ).

I have a site which accepts bitcoins. In order to validate payments I ask customer to submit txID which I use to look up the transaction. The problem is that customers sometime submit wrong txID, not full txID .. etc.

Is there a way to validate transaction ID WHEN USER SUBMIT IT TO THE FORM and if is correct then save it and check it?


texts: Assuming I spent 1BTC, then waited a few months and then spent it again. How is this detected? Do the miners go through the entire blockchain to assure the coin was never spent before?


texts: How to manually sign a transaction with multiple inputs and multiple outputs?

texts:
I'm developing transaction constructor, but i faced several problems.  To some of which i found answer in How to sign a transaction with multiple inputs?, for the rest i'll try to explain:

When we have multiple inputs and multiple outputs and try to sign every input what do we fill in the output value section for each one of them: The total sum of the transaction inputs or the corresponding amount that every input that we sign has and we distribute between the outputs?

'version': 1,
'inputs': (2)
    {
    'output_tx_hash': 'aaaa',
    'output_position': 0,
    'script': the original script, like: '76a914' + hash + '88ac',
    'sequence': ffffffff,
    }, {
    'output_tx_hash': 'bbbb',
    'output_position': 1,
    'script': '', # Nothing
    'sequence': ffffffff,
    }
'outputs': (2)
    'value' : 100000
    'script' : '76a914' + hash of btc pub key + '88ac'
    'value' : 50000
    'script' : '76a914' + hash of btc pub key + '88ac'
'locktime': 0

In the section script in inputs, there is "Nothing", but what is the exact byte count of it - 1 byte, 4 bytes or something else?
Is there a step-by-step guide or tutorial for manual transaction building and signing that covers multiple inputs and multiple outputs transaction. I successfully send transactions to the blockchain but only the ones with one input.


texts: Different ways to encode Bitcoin Address

texts: What are the different ways to encode a Bitcoin Address (both private and public) and how are they calculated? I've heard of things like firstbits, mini private key format, and I`d like to know how does one convert one number into another.


texts: Private key to mnemonic words, is it safe?

texts:
Is it safe to do the following?

Suppose I do not want the HD wallet, but I do want the convenience of using mnemonic words to remember the private key. I know I can convert the private key's hex representation to byte format from which I can get binary format, from there I can follow BIP-39 to generate 24 words that are represented by that private key (because general addresses are used by randomly producing a 256 bit word which is equivalent to 24 words). Can I now use these "mnemonic" words to remember my private key, and completely disregard it (since I can always use these words to get back to the private key). I guess what I am wondering is whether there are cases where different private keys can produce the same collection of 24 words.


texts: Verifying a bitcoin Signature and what is the transaction data that is signed?

texts:
Given a bitcoin transaction where it is able to redeem it's UTXO's, how can I verify in Java if the signature is actually a valid signature or not. I was trying to use the Bouncy Castle library where I was trying to recreate the message that the private key signs over.

From what I know I need the following things -

1.The version number(4 bytes)
2.The number of Inputs(1 byte)
3.Transaction hash of the input being redeemed
4.Index of the output being redeemed (4 bytes)
5.ScriptPubKey of the output being redeemed prepended with the length of the script
6.Sequence Number(4 bytes)
7.No of outputs we are signing over(1 byte)
8.Total value of the output(8 bytes)
9.ScriptSig for the output prepended with the length
10.locktime field(4 bytes)
11.hashcode type(4 bytes)

I have tried to capture this information from the transaction data but when I try to verify the signature, it fails. Am I missing something?I want to be able to verify if a signature is correct. Thanks.

From what I have read, Step number 5 is a temporary step and the ScriptPubkey is replaced by some other value but I am unable to understand what that value should be.


texts: I'm trying to mine using my CPU and GPU. When the CPU is set to use all its cores, I have no problems, but when I use my GPU, my desktop gets way too slow because unity uses it too I think, so I need to find a way to be able to use my GPU for mining while using Intel graphics for unity and the rest, can anyone help? I have a Nvidia GTX 850M and Ubuntu 16.04, and I don't know where to begin.


texts:
When i run getblocktemplate, Bitcoind gives me in the version field a decimal number, when i convert it to Hex it's 20000000
I know it must be in little endian, but to build the blockheader must i put it like this 00000020 or 02000000  ?
I am asking this question because in version 1 the blockheaders are using 01000000 and not 00000010 so i am confused
Help is appreciated
Thanks to all of you


texts: Would nine 1MB transactions potentially create havoc on the BitcoinCash network

texts:
It appears that the BitcoinCash chain is still on its original BCH main chain, and non-upgraded mines/exchanges/wallets can still transact there.
What then would happen if nine (or more) 1MB transactions were created by padding the comments so each transaction was just under 1MB.  Assuming that these none-or-more transactions all had attractive Satoshi's per byte, is the following scenario possible?  If not why not?

Upgraded mines would try and fill a new block with nine (or more) 1MB
transactions while non-upgraded nodes would try and fill a new block
with exactly eight of them.
If an upgraded mine won the next block, then it would create a
physical 32MB consensus rule fork with an initial 9MB block off of
the main chain, and we would be able to see this >8MB block in a
BitcoinCash block explorer (at least for a while).
Subsequent blocks mined by non-upgraded nodes would extend original
8MB non-upgraded main chain, whereas subsequent blocks mined by
upgraded nodes would extend the upgraded now hard fork chain.
Meanwhile exchanges/wallets which have not been upgraded (possibly
some major players due to non-consensus seeking nature of this release)
would operate only on the original main chain, while those that have
upgraded would operate on the upgraded chain, assuming it is longer.
Periodically the chain with the largest cumulative work would
cause transactions on the other chain to be sent back back into the
mempool, potentially allowing this process to repeat assuming that
the new upgraded chain had less cumulative work and that the new
upgraded chain again won the next block race and wrote a new 9MB hard
fork block.
Should this work, the overall effect of this could be tantamount to
a temporary denial of service attack on the BitcoinCash network.


texts: how to get private key of old receiving address in blockchain.info. I have passphrase!

texts: I have mistakenly sent bitcoins to my old receiving address from Unocioin wallet and later i imported it into my wallet but it is not transferring it is asking private key. neither I' m able to send to any because it is asking me private key but i didn't know where it is? i have passphrase but how can i generate private key with passphrase?


texts:
I am hearing about a new crypto currency BTU with another block chain. If BTU comes up,

What will happen to our existing BTC? Can we still use those? Will those be of no use?
Will the price of BTC rise or fall?
Will the price of BTU be same as BTC?
Can we convert BTC into BTU?

Appreciate your quick response.


texts: At which point and how does the miner who successfully solved hash get coins?

texts:
When miner creates a valid block he broadcasts that to the network.

It can happen that someone else did the same. So we have half nodes think that chain+A is correct, and other half that it is chain+B. This gets resolved when next block is solved.

When are the coins given to the miner, or are they given to both miners?
How do the coins get sent to the miner?
Does the solved block contain the identity (public address) of the solver so the protocol can send him money?
https://en.bitcoin.it/wiki/Block_hashing_algorithm - can't find that address here

EDIT: Now it seems to me that both are rewarded, each inside his respective fork. Something like the reward transaction is put inside that chain-head. When one fork wins the respective reward stays as valid and the other fork is dropped by community. Am I correct?


texts: How can you find how many keys you wasted in bitcoinj?

texts:
Supposed you create a new wallet and pre-populate it with 100 keys (so you don't need to back it up after each transaction).

How do you know, given an instance of Wallet, which keys have been "used up"? Or, in other words, if you want to use a new key for every transaction, how do you which key to use, given only the wallet state?

Are you supposed to save this information elsewhere?


texts: What is the difference between inbound and outbound connections?

texts:
I have port 8333 open with 8 outbound and 2 inbound connections.

Is my node transmitting and receiving transactions and blocks from both types of connections? Or does the "inbound" flag mean I am just downloading from that peer, and not sending any information back?

If, for the sake of saving RAM, I set maxconnections to 8, will they all be outbound? Even if port 8333 is open? In this configuration, is my node still "helping" the network?


texts: bcchanger.com: why are bitcoins being sold at 1/3 market value?

texts:
Why are bitcoins being sold at 1/3 market value at bcchanger.com?

Are the lowball sellers trying to scam people or throw away money?


texts: Unconfirmed transaction for nearly 3 months

texts: Sorry but I am fairly new to this. I have qt wallet and have done quite a few transactions, but around Xmas time I placed a few payments that didn't go through. After  checking the web, many said just to wait and the coins will come back. But as it's now been 3 months, is there anything else I can do? Please be basic as I'm not that experienced.


texts: Is there a risk in entering my Bitcoin-Core wallet passphrase, if it's for sending all my available balance and never using that wallet again?

texts:
I have Bitcoin-Core wallet.dat with a single address and a small amount of bitcoins in it.
Say I want to send all the available bitcoins I have, and then never use that wallet again. Can I use an online computer for that, including entering the passphrase while connected to the internet? Will anybody be able to steal any bitcoins from me?
Thanks


texts: How can't a malicious attacker generate bitcoins on his private network?

texts:
I'm new to the cryptocurrencies world and I'm trying to understand how all this stuff works, so expect a really noob question.

Suppose there's a user which generates a number of addresses and sets up his private blockchain. One of this address will start illegal transactions moving money that doesn't really exist. Since the other nodes of the network are controlled by him, the transaction will be validated. Now this address is moved from his private blockchain to a public pool.

How does the blockchain knows/prevents the malicious node from spending money that are not really there?

Thank you!


texts: Bitcoin passphrase fail, restoring backup does not help

texts:
Bitcoin passphrase fail steps to reproduce:
I installed bitcoin-qt version 0.8.1 around March 22, 2013.
I let it sync for about 48 hours until it was completely up to date. No error messages.
I set my wallet passphrase with an 11 char mixed case alphanumeric. CapsLock was off.
I wrote down my passphrase on paper and stored it in two separate fire resistant vaults.
I created a receive address and received coin sent from mtGox.
I let the transaction verify by more than six hosts.
I created a new address for offline storage and sent the coin to it.
I waited for at least six verifications.
I created two backups of the wallet.
The two backups compare exactly via windows comp command.
I stored the backups on USB drives in two separate fire resistant metal vaults.
I exited bitcoin. It was not set to start automatically on system login.
I did not execute bitcoin for the next eight months. No block updates.
Windows Auto Update was on.

On November 19, 2013 I started Bitcoin again for the first time in eight months.
As Bitcoin attempted to sync it produced many identical error messages something like:
      “failure to read block”. After each error I stopped and restarted the program.
The errors occured at random intervals on average about an hour apart.
Trying to eliminate the error messages I upgraded to version 0.8.5 while
version 0.8.1 was running, and I saw no error messages. I restarted the computer.
Bitcoin continued to fully sync receiving blocks with no more error messages.
Next, for the first time I checked the box “Start Bitcoin on system login”.
I observed over the next 10 days that bitcoin 0.8.5 remained sync'd with no error messages.

On November 28, 2013 I attempted to change my passphrase and received the error:
      “The passphrase entered for the wallet decryption was incorrect.”
CapsLock was off. Same keyboard, same system (except for Windows Update).

I backed up my wallet and compared the new backup to the two previous backups.
The Windows “comp” command reports the new backup is different from the two previous backups as

follows:

  dir
  04/09/2013  12:40 PM            73,728 Long Term Savings Bitcoin Wallet.dat
  11/28/2013  04:48 PM            73,728 New Backup after passphrase fail msg.dat
  04/09/2013  12:40 PM            73,728 Wallet Backup 2013 04 09.dat

  comp
  Name of first file to compare: Long Term Savings Bitcoin Wallet.dat
  Name of second file to compare: Wallet Backup 2013 04 09.dat
  Option:
  Comparing Long Term Savings Bitcoin Wallet.dat and Wallet Backup 2013 04
  09.dat.
  ..
  Files compare OK

Compare more files (Y/N) ? y

Name of first file to compare: New Backup after passphrase fail msg.dat
Name of second file to compare: Long Term Savings Bitcoin Wallet.dat
Option:
Comparing New Backup after passphrase fail msg.dat and Long Term Savings
Bitcoin
 Wallet.dat...
Compare error at OFFSET 8014
file1 = 6
file2 = 4
Compare error at OFFSET 8016
file1 = 34
file2 = 0
Compare error at OFFSET 8017
file1 = 16
file2 = 1C
Compare error at OFFSET 801A
file1 = D4
file2 = 78
Compare error at OFFSET 801B
file1 = 1B
file2 = 1F
Compare error at OFFSET 801C
file1 = 34
file2 = 0
Compare error at OFFSET 801D
file1 = 16
file2 = 1C
Compare error at OFFSET 801E
file1 = 78
file2 = D4
Compare error at OFFSET 8020
file1 = FC
file2 = A0
Compare error at OFFSET 8021
file1 = 1B
file2 = 1F
10 mismatches - ending compare

Question 1.) Does bitcoin-qt version 0.8.5 intentionally produce a different .dat backup than 0.8.1?

So, I shutdown bitcoin-qt and replaced wallet.dat with the March 22, 2013 backup.
(in C:\Users\MyUserName\AppData\Roaming\Bitcoin) and restarted fully sync'd with no error messages.

Once again, I attempted to change my passphrase and received the error:
      “The passphrase entered for the wallet decryption was incorrect.”
CapsLock was off. Same keyboard, same system (except for Windows Update).

Question 2.) Any suggestions?


texts: Why different pages report different number of mempool transactions?

texts: I see different reports of transactions in mempool. From 35k (statoshi.info) over 170k (blockchain.info) to 215k (bitaps.com). All pages claim to report in realtime. Why is that? The difference is so big that it can not be caused by sync delays..


texts: Transaction confirmed by network but never showed up in bitcoin-qt

texts:
I've sent a large amount of coins to 1K7SzBTPGyyEtWsudwHpjg31LjrPf17qr4 but my bitcoin-qt client (V. 4.7.4) doesn't show any balance.

1) Under the "Receive coins" tab it shows the same address
2) The client is synced and up to date
3) Under the "Overview" tab it shows 0.00BTC for both "Balance" and "Unconfirmed"
4) Under the "Transactions" tab it shows no transactions
4) http://blockchain.info shows 278 Confirmations.

Any ideas? I am getting real worried now.


texts: How to recognize dependent transactions sitting in the mempool?

texts:
I am trying to find out the relation among dependent transactions in the mempool.
I have already used the "depends" field and tracked the transaction ids to go through.
But I still can not clearly figure out how and when this field is modified or updated to show the dependencies.
I am looking for a scenario for that as well.
Thanks


texts: OP_LSHIFT & OP_RSHIFT purpose & functionality

texts: What is the purpose & functionalities of the LSHIFT & RSHIFT Script OP codes ?


texts: Is there a way to set up proof-of-work systems so they would be even more useful?

texts:
One of the arguments made against Bitcoin's design choices is that it wastes resources authenticating transactions. In particular, finding small hashes is completely useless for the world.

Are there approaches (or other crypto-currencies) that use proof-of-work by working on some useful difficult problem? There are plenty of projects like SETI@home or Folding@home that distribute difficult but potentially useful calculations among different users, is there a way to use such useful calculations for building a proof-of-work system in a crypto-currency, or is there a fundamental reason (economic or computational) that a proof-of-work must involve useless work?


texts: How do thin-clients know in which blocks to look?

texts: Using SPV the client can assure that a transaction is inside a block, but how does it know in which blocks to look?


texts: How to start using signrawtransactionwithkey instead of signrawtransaction

texts:
I am following this tutorial, which says to use signrawtransaction. However, I get:

error code: -32
error message:
signrawtransaction was removed in v0.18.
Clients should transition to using signrawtransactionwithkey and signrawtransactionwithwallet

The API call in the tutorial shows this:

$ signedtx2=$(bitcoin-cli -named signrawtransaction hexstring=$rawtxhex2 | jq -r '.hex')

How do I do that same thing using the new signrawtransactionwithkey API? I started by generating a 256-bit private key:

https://gist.github.com/rietta/3640002

Now I'm not sure what to do. I guess I am to do something like this, but not sure exactly how to define it using CLI variables and such to make sure it's going to work.

signrawtransactionwithkey  "0200000001cfe62b9f1c52bc2998f9a0e6d6ee35430c93ec653d5691935178147a43090fee0000000000ffffffff01f0afd320766191d4c5c088ac00000000" "[\"cSXHtKRXWnCLWhuie8WC13cKF3qdnKL8vG3BiRpxgCXZkK2CHe9u\"]"  "[{\"txid\":\"ee0f09437a1478519391563d65ec930c4335eed6e6a0f99829bc521c9f2be6cf\",\"vout\":0,\"scriptPubKey\":\"a914111111111111111111111111111111111111111187\",\"redeemScript\":\"5221033d9aecbced8e776c03d283f6c0d64c6a301ad142d74d500fe8860c9b362fa4932102a4df3cb4e5286e180b7c68e323c778e32350a604d4f4a74c290d1c60c721687a52ae\"}]"

Looking further, I need to base58 encode the key.


texts: Real-time price data for cryptocurrencies

texts:
I need some source (preferably free) for real-time (or some reasonable time lag) for quotes of cryptocurrencies. Can you suggest anything?

What does Kraken or Poloniex use?


texts: Bitcoin full node - how to run a pruned node, explaining pruning?

texts:
can you explain please how I can run a "pruned" node instead of storing all 300GB of data? Is there a difference how you turn your btc client into "pruning" mode among the different clients, bitcoin core, bitcoin QT, electrum?

If i run one of those 3 mentioned btc clients, I would like to know how to turn that program into "pruned mode"?

Any security factors to keep in mind when using pruned node mode?

Thanks


texts: What's the distinction between BIP 157 and BIP 158? Are they supported by Bitcoin Core?

texts: BIP 157 and BIP 158 are both concerned with Compact Block filters. What is the distinction between them, and which of them does Bitcoin Core currently support?


texts: Electrum exchange rates. Where do they come from and why are they incorrect?

texts:
On the simple view on the Electrum client, the value of the bitcoins is displayed in USD, GBP and EUR (changeable by clicking on it).

Currently by clicking through, I am seeing exchange rates:

10.29GBP/BTC
10.40EUR/BTC
11.90USD/BTC

This is completely out of line with mtgox, and also completely out of line with international currency markets (currently 1.6usd/gbp and 1.24eur/gbp)

So could someone explain where these rates come from and why they are so incorrect?


texts: How much currency, on average, to expect from Bitcoin mining?

texts:
As mining difficulty continues to rise, I don't know if it is even worth trying.

My question to the users actively mining is, how many Bitcoins, on average, are most miners making? And any recent numbers you are willing to share from your mining operations would be appreciated, too.

This question may be impossible to answer without knowing what hardware and software most miners are using. So I ask a secondary question: what are the dominant hardware and software configurations used by the current players in the mining game?

Finally, who are the most successful miners, how many Bitcoins are they mining, and are they mining with incredibly advanced and expensive mining hardware?


texts: What exactly is the definition of a Bitcoin node?

texts:
This page claims there are about 11k nodes in the Bitcoin network. I wonder what exactly constitutes a "node" in the network. For example, if I connect to the network and do nothing, am I still considered in this 11k figure? Or do I have to have an "effect" on the network in some ways, e.g., broadcasting empty blocks or trying to mine honestly.
Another question is do mining pools, as a whole, count only as a single node in the network?

In general, what's the precise definition of a node in the context of Bitcoin network ?


texts: What's going to happen if someone has access to my Bip32 root key?

texts: Can my bitcoin get stolen if someone else has access to my Bip32 root key?


texts: I have bought bitcoin in the past but forgot which wallet it was. Anyway to find it with wallet address?

texts: Is there any possible way? I bought it back in March, 2017 and forgot about it and now I remember I bought it in the past with coinmama but forgot which wallet it was sent to.


texts: Does the Bitcoin client generate bitcoins automatically?

texts: I mean, you just need to install the software, and with the time, you will get lots of bitcoins?


texts: What has happened with the investigation of mtgox.com?

texts: Why hasn't there been any update since 9th of September 2015? What has happened since then?


texts:
Is there a difference between the multi-signature and Shamir's secret sharing?

Technology/algorithm-wise.


texts: New Blockchain.info wallet but where are my bitcoins? How to access them?

texts:
I have/had a wallet with Blockchain.info containing 2 bitcoin addresses. One address contained 0.33 BTC.

Yesterday when I wanted to access my wallet, for whatever reason, I couldn't remember my password, so I thought, no issue, I just can re-enter my wallet using my 12 words, so I did. I tried to recover my wallet with these 12 words and I was given another wallet (another wallet ID I mean).

The problem here is that I cannot see my funds and my known bitcoin address! I can import the bitcoin address (as I can for any address but then it is 'read only').

Can someone explain me / help me how I can recover my funds? These funds have always been in my old wallet (former wallet-ID).


texts:
Greg Maxwell noted that there are two ways to integrate Simplicity into Bitcoin. One is to make only a few select high-level constructs available (like SHA256, CheckSigHashAll), the other is to expose a full bit machine as specified in the Simplicity Technical Report.

Now that Simplicity is being integrated, presumably a decision must have been made on how it will work.

Which approach was chosen?


texts: How can I generate thousands of receiving addresses from a Bitcoin wallet?

texts: I want to generate thousands of receiving addresses without sending any BTC to another wallet. Is it possible and how?


texts: Is there a way I could set up my LTC mining pool so that my friends could join? I've been having really good luck lately!


texts: Please can anyone recover my coins from a dark wallet stealth address, how do i go about recovering the private key?? i have the seed but i don't know what derivation path the stealth addresses are stored, please help me


texts: Is it possible to calculate the transaction size from the transaction id ?


texts:
I'm relatively new to the world of Bitcoins and understand the basic principles of wallets and addresses etc, but was wondering how exchanges (like Coinbase) work exactly.

Is the entire exchange basically one large wallet with each user having their own address? That would mean that an exchange would hold a wallet containing all their users Bitcoins, no?

When you buy Bitcoins from an exchange using a bank transfer or credit card, where are the Bitcoins you're buying sourced from? It was my understanding that you have to buy Bitcoins from an individual who's actively selling their Bitcoins. Do they just buy a massive amount of coins all at once and slowly sell them off?


texts: Can you send bitcoins together from the same wallet if they have been received via various different addresses?

texts: What has been sent to your individual bitcoin addresses is supposedly recorded in the blockchain, but can you then send all of the combined bitcoins (that you received via various different addresses) at once with your public key? For example, if I received 1 bitcoin via address 1, 2 via address 2 and 5 via address 3, all of these addresses being derived from the same public key, and I wanted to send 6 btc to a friend, could I send all of them at once with my public key? Or would I have to send a combination of bitcoins from different addresses, i.e. by separate transactions? And if I could send them all together using the public key, how is it determined that I am in possession of all of these bitcoins if they were sent not directly to my public key, but to various irreversibly hashed addresses derived from my public key?


texts: How do you get a job in the Bitcoin/Blockchain industry?

texts:
I'm 18 and would like a job working in the Bitcoin/Blockchain industry but I wouldn't know where to start.  Economics degree?  Perhaps working for the fin-tech branch of a bank?

I'm interested to know about how people in this industry got there, what they think about it, and any advice.


texts: Is there a place or tool to monitor all addresses for unmoved coins?

texts: I've been looking for a way to easily monitor all address with a balance, that the balance has not moved/changed for a period of time (based on a criteria such as 1 year). Is there a site/tool already available? or do I need to build it myself? if I have to build it, where can I start to look for the relevant data? Thanks


texts: blockchain.info seems to source transaction money from an address not in my wallet

texts:
Today, I have send a transaction with too low a fee:

https://blockchain.info/tx/84eb8a6c6562a9cfedc0e82c7fbe3355615b8154e376db0a325b4ae4f26180b2

I have retrieved the twelve word pass phrase from my wallet on blockchain.info, and calculated the private keys for the addresses in my wallet. However, the address

1PUBmT2fzVMtNWg58K67knqoz58MmCJ8pn

is not amongst these, and it is also the only address that does not show up in my blockchain.info wallet. Therefore it I can only double-spend part of my first transaction (so to void it). What is happening here?


texts:
After a lot of reasearch on the net, I still can figure out if the following idea is relevant or not :

I know (or at least I think I know) that each transaction consume all the bitcoins present at the inputs addresses. So if a bitcoin address is in the inputs of a transaction, you don't have to look at all the transactions older than this one to know how much bitcoins there is for this address. That means that we could remove all these olders transactions from the blocks keeping only there hashes via the Merkle pruning trick. With time, the Merkle Trees in each old blocks will become smaller and smaller so that space can be spared.

I understand that it will erase forever a part of the transactions, but the number of bitcoins for each bitcoin address will remain correct and perhaps that's the price to pay to keep a managable blockchain.

Is there already some work in this direction ?
Is this a stupid idea ?

Thank you for your help


texts: Bitcoin animation from The Good Wife S03E13

texts: Is the Bitcoin-related animation that appeared in The Good Wife S03E13, quite similar to the one on WeUseCoins, available anywhere on the internet in full?


texts:
Lets say I open a lightning network channel and the other party goes offline. Lets say I haven't actually used the channel yet. What if I want my bitcoin back from that channel so I can use it.

I payed an on chain transaction fee to open the channel, I can close the channel again but will have to pay another on chain transaction fee to close the channel. Effectively I will have payed for two on chain transactions without actually transferring any bitcoin.

If I go to pay and the other end of my channel is down. It would take me two on chain transactions to be able to make the payment (one to close the channel and one to open a new one) my instant and almost free payment has now become extremely expensive and slow.

What steps do the lightning network implementations take to limit the impact of this kind of thing? When your lightning wallet choses a node to open a channel with, does it take into account how reliable that node is, IE how long it has been online for / how much down time it has had?


texts:
I have used bitaddress.org to create a brain wallet for my Bitcoin.
Now I would like to create a brain wallet for my Ethereum using Bitcoin Improvement Proposals (BIP) 32/39/44/49 technologies. Is there any reputable tool (preferably similar to bitaddress.org) or open source command line tools I can use to generate a brain address for Ethereum?

Thank you all


texts:
I have some server on hostinger.
there is any software or script with that I can mine for with one time setting....
I tried for php script search in Google but can't find
Sorry for my poor English
Pls give miner or script and pool's name link......


texts: Why should I keep my coins in an exchange?

texts:
If I have 1BTC in a wallet anywhere, which I bought at mtGOX for 20USD, and now that 1BTC is worth 130USD on mtGOX, I can simply send my 1BTC from the wallet to mtGOX and withdraw to a bank as USD and have netted over 500% profit after fees right?

So my question is: why would I keep my BTC in the "live" trading of an exchange rather than just keeping it in a Wallet?  There's no difference to me right?


texts: The COPAY app I have 2 wallet,BTC and BCH. I transferred Cash to Bitcoin address BITCOIN, money stuck so BTC WALLET does not accept BCH how to get the money back or transfer them to BCH WALLET


texts: So exactly what is the value of a Bitcoin in relation to the American dollar?

texts: Ok, if I want to buy something that is $8 in American dollars and use a Bitcoin that is worth an odd value in American dollars...like $17 for instance. Then what happens? I end up with a deciminal point version of a Bitcoin? How does an individual keep track of Bitcoin money when it translates into too many decimal point locations? Doesnt Bitcoin have 8 or 10 decimal places? What happens if you buy something from a country where money is worth very little? Could you have a bitcoin account with a long decimal point fractional value?


texts: Armory Wallet With 2BTC Gone After 3 Years! HELP!

texts:
I purchased 2 bitcoins with CoinBase online 3 years ago. I then sent them to an Armory wallet that I had on a server. Everything transferred successfully and I never thought twice about them disappearing. I have a paper back and an encrypted Armory backup of my wallet. I never made any further transactions.

I finally want to access my BTC in my Armory wallet. I started Armory and the program seemed to freeze many times without loading the block chain. I removed Armory and BitCoin-QT (now BitCoin Core). I installed the newest versions of both programs, downloaded the full block chain and restored my wallet using both the paper backup and the encrypted backup.

The balance of the wallet seems to be 0BTC no matter what backup I use. What happened to my 2BTC and how do I go about getting them back. I have full backup images of the server (c drive and d drive) before removing and reinstalling the software, if that helps.

I just can't seem to figure out where the heck my 2BTC went! Please help!

Here are all the details I could find.

My wallet after using my paper restore has the following two addresses.

Transaction #1 (small amount for testing)
Send to address:1CqmjgYj46vRqBxFvbt5WsqMudRShhGKmD
Transaction #: a821fac9e6216975fa8216045a3cd9ae500a82aa251988ca1f301c7287b74ab4

Transaction #2 (sent minutes after transaction 1)
Send to address: 16D1XkRHunUgSfuPDQZSPG42cAicTbSmzu
Transaction #: 5187441186fa834d8a27fb9302bbcb6d3993ff836e1918f8174d5b3266ffb21d

Transaction #3 (sent a month later)
Send to address: 1qjThyMzMrpy3m1esvXF32o3MHVixnxnA
Transaction #: 707e5f96d88134da5f5936b541df19faa9d7e5819d478bd5d533cbb2e9be62c9


texts: How to generate the public Nextcoin key (NXT)?

texts:
There doesnt seem to be an API call that returns the public key for my NXT account (with which I have not sent out any coins yet).

The NXT wallet does display the public key after I log in, but how do I calculate this public key programmatically?


texts: Now that my GPU mining rig will be made obsolete, where to turn?

texts:
With the return from GPU mining likely to be affected by ASICs, where can miners turn their machines? Should I become a pro gamer? Join a rendering farm for cash (do they exist?) and let Disney use my rig to make toystory 4? Donate it to SETI@HOME or FOLDING@HOME? Donate it to an Anonymous botnet? Join a spamming farm used to bombard Bitcoin dev's with requests to switch double-SHA256 for double-MD5 in the code?

In short, what serious alternatives are their for profit or just putting to good use mining rigs?


texts: How old do you need to be to buy bitcoins in a atm?

texts: I've read all the others Q&A and I haven't found the answer to my question or I haven't noticed. I live in Spain and is there an age restriction to use an btc atm (I'm 16)?


texts: How can market-based transaction fees scale?

texts:
Can someone please explain to me what I am missing?
I don't see how variable, market-based transaction fees can scale. I go to a merchant's website to buy, how do I select a mining peer to pay transaction fee to? Do I attach some bounty that any peer can earn if that peer wins the Proof-of-Work block? But what if my bounty isn't high enough to attract a peer given high transaction volume competing for priorities? Or not enough to cover any peer's mining overhead. How do I know how much to bid to be sure my transaction completed in a timely manner?
This sounds very complex and unreliable and not at all like something that can scale to customers. Customers want to click one button and be done with the purchase and not waiting unknown hours debugging their payment processing. Amazon's One Click.
I don't see how with different peers charging different fees (to match their market dynamics), the sender of a transaction can know the amount to bid to get in the next block? It is impossible because the tx fees are not uniform and the random selection of the next peer is not knowable in advance.


texts: Ripple paper wallaet from Rippley (https://ripply.eu/) code check / safe?

texts:
This question is about Ripple, but I hope it's still okay to ask this question on Bitcoin StackExchange:

I am eager to put my Ripple in a paper wallet, and from searching the web I found Rippley.eu (https://ripply.eu/).

I was wondering if anyone has done a code check of this website, and can verify that it's safe to use for generating paper wallets for Ripple storage?


texts: Do we need in-app billing for bitcoin-like app?

texts:
Apps that use bitcoin contains transactions e.g. deal with a real money. Google says that if we deal with a real money, it has to go over their in-app billing service.

I checked other bitcoin apps on the Google Play, but neither of them seem to have in-app billing implemented.

So do I have to implement in-app billing for bitcoin-like app or I can make transaction without it?

I don't want to build and publish the app which will be blocked as violating TOS.


texts: Can we determine which one of the referenced outputs corresponds to a cashback transaction in BTC transaction scripts?

texts:
let me quickly elaborate the question. The structure of a BTC transaction script looks somewhat like the following example

"01000000018190374a5a1feb54fab4417fac1a3d9185de06fd8dcac34822c7cd00083638b1000000006a4730440220237ef9d9a3908f163ee37cc65de642ba1d45e399cde840285cd1658292ee71f902201a2fa3959cf19e64308d64a052526b755e22f2efb941675bc35684de1d90e7dd012103c13dca192f1ba64265d8efca97d43b822ff24db357c13b0e6e0395cf91e9efaeffffffff0248ac0b00000000001976a9140964c6feb963ade6836e722670abbc0147ca5cec88ac08100b00000000001976a914977ae6e32349b99b72196cb62b5ef37329ed81b488ac00000000"

... where the part

"48ac0b00000000001976a9140964c6feb963ade6836e722670abbc0147ca5cec88ac08100b00000000001976a914977ae6e32349b99b72196cb62b5ef37329ed81b488ac"

... specifies the two output addresses that the money from the UTXO(s) is split and sent to.
Often, as the sum of one or several UTXO's does not perfectly equal the amount that the sender wants to transfer, as last (?) output address he references his own address, in order to receive back his remaining cash.

My question is, is it somehow ONLY from the transaction script structure as above determinable which of the referenced output addresses correspond to the(se) "cashback address(es)"?

I have a few thoughts on this myself:

Of course, the sender might have several addresses / accounts, anyways, then, we have no chance at figuring out whether he is sending money back to himself or not.

Furthermore, I suspect the answer to my question is no, as otherwise, it could be possible to identify one input address of the regarded transaction as the output address that corresponds to the cashback part. This, I guess is exactly intended not to happen, as we want to keep the anonymity of the sender.

Lastly, I am aware that it is possible to identify cashback transactions when you look at the entire history of the blockchain and keep track of which address "holds" what amount of BTC / UTXO's right now. However, in order to do so, you would need to store all the addresses named in previous transactions throughout time, which is quite computationally costly, as you proceed through time in the blockchain.
Thus, I am asking for a way to quickly identify such cashback transactions. (We can for instance always easily identify the coinbase transaction in a block from the structure of the code.)

That's about it. I am looking forward to your comments, hopefully someone can shed light on this :)
Thanks!

Best,
Jen


texts:
I have transferred 1 BTC from JAXX Wallet to Armory. But it is not showing up on Armory.

The transaction was confirmed so I know it was delivered to my Armory wallet but I can't see or access it on Armory.

Can anyone tell me what I should do?


texts: To run bitcoin core testnet on Ubuntu 16.04

texts: How can I run Bitcoin core testnet version on ubuntu 16.04 platform ? I am getting so many reference about how to run bitcoin core mainnet but it will take around 20 days to synchronize with the network as per my bandwidth and also will take my half of the HDD. So I opt for Testnet. Can someone explain me how to insatll bitcoin core testnet on Ubuntu 16.04? I would be grateful. Step by step explanation or reference would be much appreciated.


texts: Verifying transactions on a 2013 version of qt

texts: In 2013 i bought 25 bit coins and basically forgot about them. I stored my wallet on  external usb's or so i thought, when i went to upgrade block chain on a new computer the wallet on the usb was not there. So i found my old laptop and booted up bit coin, the coins are there but are unverified, i must not have completed the block chain. I have been running the old qt version for a couple days now also have an outdated warning and to upgrade. so my questions are how to verify my coins? on the old qt, do i keep it running or upgrade to new core without verification. thanks for your time.


texts: Transaction created, but txid not found on blockchain explorers

texts:
Transaction created as same others, but status - 0/unconfirmed
And txid nod found in block explorers
Transaction ID: e9c858f852a1de7c70e6f8377f2147f3def1d4b1d85a5947d028bb9c13450318

How to succefuly complete this?


texts: How do I securely store different CryptoCurrencies?

texts:
I may be seen as a newcomer and and a non-tech-savy person for asking this, but after serveral hours combing the internet, I now have to admit my defeat and ask the question instead of just finding the answer myself.

For long I have been wanting to invest in more "exotic" crypto currencies. What is the most secure way to do long-time investments in crypto currency?

I don't like the idea of having my currency lying at a broker, and ideally I would like to buy a currency, transfer it to a cold wallet, and then let the wallet and backups thereof sit offline until I believe it's time for selling the currency again.

Is this possible to do for anything else than BitCoins and Etherium?


texts: How do people using thin clients know the correct merkle path of transactions they've sent without knowing the full block?

texts:
User A send a transaction to user B. Those transactions are bundled together into a merkle tree. User A and B can both use the transaction plus the merkle root, plus the merkle path to prove the merkle root in the block header is correct.

I understand all that.. what I don't understand is how do A and B know the correct merkle path without needing the entire block?

Do they need a centralized provider that processes the blocks to calculate these for them? Is it possible to do in a decentralized way?


texts:
I need to make a transaction of 0.00744000 BTC using the site CoinPayments.net. However, when I click on "Add new deposit address" in my wallet, I can see a 34-character long code.
Next to it, there is a button "Deposit with Bitcoin client", but when I click on it, an empty tab opens in Chrome. In Chrome's address bar, I can see the 34-character long code and the prefix bitcoin:.

However, I don't understand how am I supposed to make the transfer then? I need to convert $50 from my bank account to BTC.


texts: Are there any bitcoin banks (online services) and what are the benefits and pitfalls of using them?

texts:
Possible Duplicate:
  Is there a solid "Bitcoin Bank" yet?

Say that I wish to control my bitcoins from a (for me) single point and I don't have the technical resources to have a single access point with a wallet amongst my own personal computers / devices.

Is there a bitcoin bank or similar service that hosts my bitcoin wallet for me and is there a benefit to such a service beyond likely better backup and being a single point to which I can manage my bitcoins without having to set up my own remote access to a home PC?  What are the reasons against using such a service?


texts:
I'm trying to sign (using secp256k1) a transaction as explained here. I'm using my own private key and an unsigned transaction as the input.

I'm able to sign it using the JSON-RPC client, but when I sign it with my own ruby script and try to submit it using blockchain.info/pushTx it returns "Invalid signature".

@secret = PRIVATE_KEY_IN_HEX
@keypair_array = Bitcoin::OpenSSL_EC.regenerate_key(@secret)
@pubkey =  @keypair_array[1]

@keypair = OpenSSL::PKey::EC.new("secp256k1")
@keypair.private_key = @keypair_array[0].hex
@keypair.public_key = ::OpenSSL::PKey::EC::Point.from_hex(@keypair.group, @pubkey)

sha_little_endian = SHA_256_HEX_STRING.rjust(64,"0").scan(/(..)/).reverse.join()
signature_binary = @keypair.dsa_sign_asn1([sha_little_endian].pack("H*"))

# Alternative (as in bitcoin-ruby)
# signature_binary = @keypair.dsa_sign_asn1([SHA_256_HEX_STRING].pack("H*"))

signature = signature_binary.unpack("H*").first

First I take the SHA hash, e.g. ABCD...001124 and convert it from big endian to little endian: 241100....CDAB. I do this because in the BitcoinQT client the hash is represented as an uint256 which is cast to a char array used as an input for signing. The result is just stored as a var so I assume I don't have to reverse it.

You'll need to download this OpenSSL_EC file and add the following code to reproduce the above steps.

require 'openssl'
require 'ffi'

module Bitcoin
  def self.require_dependency(dummy1, dummy2)
  end
autoload :OpenSSL_EC, "./openssl"
end

module ::OpenSSL
  class BN
    def self.from_hex(hex); new(hex, 16); end
    end
  class PKey::EC::Point
    def self.from_hex(group, hex)
      new(group, BN.from_hex(hex))
    end
  end
end

What am I missing?


texts: Manually create a transaction to spend the output of a P2SH tx

texts:
I want to manually create a transaction to spend the output of a P2SH tx, but I don't know where the redeem script should be placed in the new transaction?  I followed an online tutorial Building a Transaction By Hand

In order to sign the transaction, you need to build this tx message as the picture shows. But when there is a redeem script, where should i put this redeem script?


texts: Strict firewall & proxy, no stratum+tcp connectivity; what are my options?

texts:
I have access to a system for mining behind a squid proxy. No external connectivity except for HTTP & HTTPS. The access on my mining system is also fairly restrictive, but I have managed to build and compile *minerd for it.

  System specs:

  CentOS 6.5 x86_64, dual quadcore xeon, 16GB ram

This is for a project a group of us are working on; we are mining a private blockchain, not part of any *coin group (ours is based on DOGEcoin, I believe, but private).

The server only allows stratum+tcp to serverIP:3333. my minerd can't reach it due to the HTTP/HTTPS only outbound restriction.

I have looked at the Stratum Miner Proxy, but I have difficulty getting python to download what it requires to config and make/setup the proxy, when I run the setup.py

Is Stratum Miner Proxy still my best bet, or should I look into setting up a shell/relay outside the network that accepts HTTP from my miner and sends/receives stratum+tcp to the server? any other suggestions or thoughts?


texts: I sent BTC from Blockchain to a BTH wallet on Coinbase.. can I get it back?

texts: So not knowing Coinbase had just recently added BTH to their wallets I accidentally copied and pasted that address to transfer my bitcoin to. It's been confirmed on Blockchain & the coin is unspent. Is there anyway I can retrieve this coin?


texts:
How often? Is backing it up once enough?
Any best practices to storing the backup?


texts: What's the best way to get rid of 1 satoshi dust?

texts:
I recently noticed an old address of mine had 1 satoshi sent to it in some dust spam transaction. The thought of this satoshi bloating the UTXO set for everyone bothers me. I'd like to "destroy" it, but I don't want to combine it with other inputs in a separate transaction for privacy reasons. Ideally I can "spend" it in a transaction with no outputs so it just goes to the miners, but I've tried doing this on Electrum and it won't allow transactions without any outputs. I haven't tried it with bitcoind yet, but my node is pruned so I'm not sure importing the private key would work since I can't rescan far back enough.

Another good option would be to somehow sign this input and allow someone else to aggregate it with a bunch of other dust outputs and "donate" them all to the miners, but I figure this is not currently possible.

Any recommendations on a clean, simple way I can destroy this satoshi without compromising privacy?


texts:
I think this question is not only matter of bitcoin but also of every other crypto currency.

My question is if I lets say have an app or wallet or website. And I want to send money to certain address, lets say I will scan QR. Great I know the address but how to actually push the transaction to the blockchain? How I will release such info? Lets say that I would be able to see at https://www.blockchain.com ? Thanks for every answer. I am looking forward your responses.


texts: it's been a long time. I'm updating my udemy course on Bitcoin and I'm curious what educational content has been released since September of 2013 on Bitcoin. Specifically have you guys encountered an aggregated list or has someone taken up the mantle of BEP since I left?


texts: How do I calculate the sum of transaction inputs?

texts:
I am attempting to calculate the mining fee of a transaction, given it's unsigned transaction hex by taking difference between the sum of the inputs and outputs.

I also have access to an array of Txout and Txin blobs.

Taking the sum of the the Txout array is easy, as first eight bytes is the value of the output, but I do not know how to get the value of an input for a Txin.

The format of the Txin blobs is that which is described on the bitcoin.it wiki --

Previous Transaction hash   ||  32 bytes
Previous Txout-index        || 4 bytes
Txin-script                 || 1-9 bytes
Txin-script                 || arbitrary number of bytes
sequence_no                 ||  4 bytes

How can I get the value of each input?


texts: What are concrete uses of Bitcoin script?

texts:
I am looking at solutions to simplify the architecture of Bitcoin from a more theoretical perspective. I am thinking about removing Bitcoin script, however I am not sure what restrictions this introduces.
I find many vague arguments, that having script makes us more flexible, however I am looking for concrete examples.

I have the following things:

Payment channels
Gambling / distributed random generator
Storing data in the blockchain / Proof of publication

What else is out there?


texts: Asymmetric revocable commitment's revocation key

texts:
I am reading 'Mastering Bitcoin' to study for bitcoin and blockchain. At page 295-296, Author described that two parties should exchange their revocation key before signing new commitment transaction to punish when either party tries to cheat.

But, if we use this method, either party can redeem prior commitment transaction by using revocation key whenever it wants. This mechanism is being used by lightning network now. I wonder how this method prevents either party from cheating.