texts: Are Bitcoin core devs contributing to ISO/TC 307 Blockchain and distributed ledger technologies

texts:
I was just being made aware of the standardization process about blockchain and distributed Leger technologies. https://www.iso.org/committee/6266604.html

In this picture from the talk that I am attending you can see that many institutions are part of the process:

However I did not see any institution close to Bitcoin development. I asked if the standard will be compatible with Bitcoin. The presenter said they are in contact with Bitcoin developers. Where could I find more information about this?


texts:
I've salvaged my old netbook with Windows XP and have been able to access a couple of Bitcoins that a friend sent me back in 2011 (!) when he was getting into this new cryptocurrency thing. BTC was beyond my skill set then and just out of reach now -- the wallet.dat is running on Bitcoin Qt v. 0.8.5 beta.

The coins have 155140 confirmations but Qt is running 162 weeks behind -- it takes forever to load, and will never catch up to the network on this ancient machine (have kept it running for days now) -- would like to move the BTC somewhere else -- have tried sending a test amount (0.01 BTC) to a new Mycelium account on my phone but each time get this error:

Runaway exception A fatal error occured. Bitcoin can no longer continue safely and will quit. St13 runtime_error CDB() can't open database file wallet.dat error -30974

Am at a loss what to do next -- any help or straightforward advice on what steps to take in order to move the wallet.dat to another machine for an inexperienced Bitcoin layperson would be most welcome...

Thanks much


texts: Cryptocompare Api - understanding API return values

texts:
I have come across the API from cryptocompare.com which fetches data from various exchanges.

I do not understand the some values returned from the API call

https://min-api.cryptocompare.com/data/pricemultifull?fsyms=BTC&tsyms=INR&e=Unocoin

Questions

Difference between LASTVOLUME and LASTVOLUMETO
Difference between VOLUME24HOUR and VOLUME24HOURTO
Difference between TOTALVOLUME24H and TOTALVOLUME24HTO

{
    "RAW": {
"BTC": {
    "INR": {
        "TYPE": "2",
        "MARKET": "Unocoin",
        "FROMSYMBOL": "BTC",
        "TOSYMBOL": "INR",
        "FLAGS": "2",
        "PRICE": 847591,
        "LASTUPDATE": 1512451304,
        "LASTVOLUME": 0.00139926,
        "LASTVOLUMETO": 1186.00018266,
        "LASTTRADEID": "478501",
        "VOLUME24HOUR": 75.19298754,
        "VOLUME24HOURTO": 61956574.46784429,
        "OPEN24HOUR": 837298,
        "HIGH24HOUR": 860506,
        "LOW24HOUR": 491500,
        "CHANGE24HOUR": 10293,
        "CHANGEPCT24HOUR": 1.2293114279503832,
        "CHANGEDAY": 0,
        "CHANGEPCTDAY": 0,
        "SUPPLY": 16720800,
        "MKTCAP": 14172399592800,
        "TOTALVOLUME24H": 319738.400426581,
        "TOTALVOLUME24HTO": 271005614230.93204
    }
}
    },
    "DISPLAY": {
"BTC": {
    "INR": {
        "FROMSYMBOL": "Ƀ",
        "TOSYMBOL": "₹",
        "MARKET": "Unocoin",
        "PRICE": "₹ 847,591.0",
        "LASTUPDATE": "Just now",
        "LASTVOLUME": "Ƀ 0.001399",
        "LASTVOLUMETO": "₹ 1,186.00",
        "LASTTRADEID": "478501",
        "VOLUME24HOUR": "Ƀ 75.19",
        "VOLUME24HOURTO": "₹ 61,956,574.5",
        "OPEN24HOUR": "₹ 837,298.0",
        "HIGH24HOUR": "₹ 860,506.0",
        "LOW24HOUR": "₹ 491,500.0",
        "CHANGE24HOUR": "₹ 10,293",
        "CHANGEPCT24HOUR": "1.23",
        "CHANGEDAY": "₹ 0",
        "CHANGEPCTDAY": "0",
        "SUPPLY": "Ƀ 16,720,800.0",
        "MKTCAP": "₹ 14,172.40 B",
        "TOTALVOLUME24H": "Ƀ 319.74 K",
        "TOTALVOLUME24HTO": "₹ 271.01 B"
    }
}
    }
}


texts: How can I get back my bitcoin from a backup folder

texts:
I want to restore my bitcoin wallet which backup in 2013, I have the backup folder and a password(not secure words).

Anyone know how to do?


texts: Unconfirmed txes disappeared in my own bitcoind's mempool

texts:
I had a unconfirmed tx which have not been confirmed for few days. Today, it was disappeared in my bitcoind's mempool (bitcoin core v0.12.1).

The following is the tx. blockchain.info shows the unconfirmed tx.

https://blockchain.info/ja/tx/60821723b93e2ae5ed729e93c22ca824e7e91fe5a16cba3468139657dc953abc

However search_raw_transaction command does not show the tx.

curl -X POST http://localhost:xxxx/api/ --user xxxxx -H 'Content-Type: application/json; charset=UTF-8' -H 'Accept: application/json, text/javascript' --data-binary '{"method": "search_raw_transactions", "params": {"address": "178gnsM1R5gXQgo13wJDMdQTYNJqfB5LJf", "unconfirmed": true}, "jsonrpc": "2.0", "id": 0}' | grep 60821723b93e2ae5ed729e93c22ca824e7e91fe5a16cba3468139657dc953abc

I'm sure search_raw_transactions showed it yesterday.

It seems that mempool size is very big. Is it affected?

https://blockchain.info/ja/charts/mempool-count?timespan=all

And is it possible to get back the tx into my own bitciond?

Updated 1

Does the mempool size equal roughly the unconfirmed transactions?

Murch say

  Every node owner can set their own policy for the mempool. The mempool is limited two-fold:
  With -maxmempool= you can set an explicit limit of MB that it will not exceed. The default is 300MB.

I don't set maxmempool so it might over 300MB.

Updated 2

I confirmed the usage size reached 300MB. I checked it by "bitcoin-cli getmempoolinfo".

I will set maxmempool option then restart bitcoind.

Update 3

I want to make sure about the maxmempool mechanism. I believe that old txes are deleted when the usage size exceed. Is my understanding correct? Or will not new txes add mempool after the limit? If the next one is correct, it does not make sence on my case.


texts: How to scan QR code with multibit wallet application?

texts: I downloaded the multibit application for windows and was wondering if there was a way to scan a QR code with my webcam? If so where do I click because I dont see an option and no way am I going to type out an address everytime.


texts: How to make a "Donate" function with bitcoins?

texts: I understand my bitcoin wallet generates a new receiving adress everytime i received a transaction. I would like to add an adress to my website for donations. How can i get an adress that doesnt change?


texts: this bitcoin address contains transactions which may be double spends. You should be extremely careful

texts:
i sent 0.4 btc to exchanger
and this transaction was sent 2 times from my wallet and spent to me 200$ (0.8 btc)
which i wanted only 0.4btc to send
transaction hash:
https://blockchain.info/address/15o8CfP4z8cWiZCp5euzNEqXjEFTyNF5Yb
funds are still missing from my blockchain wallet more than hour ago
and at this transaction at other place when clicking on "hash" i see:
" A conflicting transaction has been detected in our memory pool. The transaction hash displayed below may change. "
https://blockchain.info/tx/f3cf0d91fd678de0bbbf13aa69e87ab3c0e7c55c3aecb03c06ac78d5139fc2b6

so my funds are gone now? or will they come back


texts:
Please guide me if following is the actual math to drive public key from a private key then how would this apply to generate public key from private key 1 please guide me step by step
Private keys and public keys
With these formalities out of the way, we are now in a position to understand private and public keys and how they are related. Here it is in a nutshell: In ECDSA, the private key is an unpredictably chosen number between 1 and the order. The public key is derived from the private key by scalar multiplication of the base point a number of times equal to the value of the private key. Expressed as an equation:
public key = private key * base point
This shows that the maximum possible number of private keys (and thus bitcoin addresses) is equal to the order.
In a continuous field we could plot the tangent line and pinpoint the public key on the graph, but there are some equations that accomplish the same thing in the context of finite fields. Point addition of p + q to find r is defined component-wise as follows:
c = (qy – py) / (qx – px)
rx = c2 – px – qx
ry = c (px – rx) – py
And point doubling of p to find r is as follows:
c = (3px2 + a) / 2py
rx = c2 – 2px
ry = c (px – rx) – py
In practice, computation of the public key is broken down into a number of point doubling and point addition operations starting from the base point.
Let’s run a back of the envelope example using small numbers, to get an intuition about how the keys are constructed and used in signing and verifying. The parameters we will use are:
Equation: y2 = x3 + 7  (which is to say, a = 0 and b = 7)
Prime Modulo: 67
Base Point: (2, 22)
Order: 79
Private key:  2
First, let’s find the public key. Since we have selected the simplest possible private key with value = 2, it will require only a single point doubling operation from the base point. The calculation looks like this:
c = (3 * 22 + 0) / (2 * 22) mod 67
c = (3 * 4) / (44) mod 67
c = 12 / 44 mod 67
Here we have to pause for a bit of sleight-of-hand: how do we perform division in the context of a finite field, where the result must always be an integer? We have to multiply by the inverse, which space does not permit us to define here (we refer you to here and here if interested). In the case at hand, you will have to trust us for the moment that:
44-1 = 32
Moving right along:
c = 12 * 32 mod 67
c = 384 mod 67
c = 49
rx = (492 – 2 * 2) mod 67
rx = (2401 – 4) mod 67
rx = 2397 mod 67
rx = 52
ry = (49 * (2 – 52) – 22) mod 67
ry = (49 * (-50) – 22) mod 67
ry = (-2450 – 22) mod 67
ry = -2472 mod 67
ry = 7
Our public key thus corresponds to the point (52, 7). All that work for a private key of 2!


texts: Just sent bitcoin to my Bitcoin Cash Wallet on Trezor. How can I retrieve it? 12-06-2016


texts: Bitcoin core node not sending outbound connections only inbound traffic

texts: My bitcoin core is not sending outbound connections. It's only getting inbound connections. Iv deleted the whole node then reinstalled it. Still it was only getting inbound connections. Iv checked firewall settings and the node is set to receive inbound and outbound connections. Does anyone know what problem might be? Could I just sync blockchain with only inbound connections?


texts: What were 'high-priority' transactions in Bitcoin Core v0.9?

texts:
I came across these release notes for Bitcoin Core 0.9 and saw this quote under 'Transaction Fees'. Does this distinction between 'high-priority' and 'highest-fee' transactions still exist? What exactly were 'high-priority' transactions?

  Note that getting a transaction relayed across the network does NOT guarantee
  that the transaction will be accepted by a miner; by default, miners fill
  their blocks with 50 kilobytes of high-priority transactions, and then with
  700 kilobytes of the highest-fee-per-kilobyte transactions.


texts: How to run a full node: Am I already doing so?

texts:
I've succesfully installed bitcoind and bitcoin-cli. I got some questions about it:

I run bitcoind in the background by typing: bitcoind -daemon and the blockchain begins to download:

By typing getinfo  I can see how many blocks are known to my client on the line “blocks”… that´s ok for me.

But what happens at the end? I don´t see that bitcoind reports me anything back on the shell.

I see by typing getinfo that the blockchain is already on my computer. Then I turn off or hibernate computer for few hours.

I run bitcoind -daemon everytime I turn on my computer and it downloads the latest blocks that, of course, are missing because my computer was turned off.  Is that all?

Am I already running a full node?

Do I have to wait for the full download of blockchain for sending or receiving BTC with blitcoin-cli?

Does bitcoin-cli  work without this large file?


texts: I have heard that mining is for people with ready hardware and blah blah blah... But what exactly is it? Does it operate like real mining? I mean, people talk about it like you are physically mining.


texts: How does the node system understand which ledger is the latest before updating their own ledger?

texts:
I have two specific questions:

How does a new user realizes which is the correct copy of the ledger to be used when initially updating(downloading) the ledger, and why is it that a user cannot deceive it by broadcasting its ledgers manytimes. (there by giving the system a pseudo idea that that is indeed the majority ledger)

How does one understand if the two ledgers are the same? Does the hash function change with the last transaction? My specific doubt would be that considering that the hash will change with the guesses too even if the last block info is the same then how does the system realize that these are from the same block even if their final values are diff.


texts: Is there a way to determine the difference between a BTC prefix 3 address and a LTC prefix 3 address?

texts:
I am trying to determine if there is a way to tell the difference between a BTC prefix 3 address and a LTC prefix 3 address, for validation purpose.

Example if given this public key address:
3HpwVq6zSd3wxSrAypFYJGKE2JTm3fvuC9

Would there be a way to definitively say it is a BTC or LTC address?


texts: Blockchain (lack of backwards) compatibility in Bitcoincore 0.10.x

texts:
From Bitcoincore release notes:

  Because release 0.10.0 makes use of headers-first synchronization and
  parallel block download (see further), the block files and databases
  are not backwards-compatible with older versions of Bitcoin Core or
  other software:

  Blocks will be stored on disk out of order (in the order they are
  received, really), which makes it incompatible with some tools or
  other programs. Reindexing using earlier versions will also not work
  anymore as a result of this.
  The block index database will now hold headers for which no block is
  stored on disk, which earlier versions won't support.

How exactly does the new blockchain format effect blockchain parsing projects (of blkxxxx.dat files) which likely rely on the old format? Is there a work-around? Are there any other specifics worth mentioning?

Examples of specific projects:

John Ratcliff C++ Blockchain parser
Python code


texts: If miners switched to random pools every hour, would it help the network?

texts:
A Miner is using Pool A

After 1 hour the Miner closes the mining software and switches to another pool (Pool B) that is randomly selected.

Would this be beneficial for the network as the hash power is now randomly spread out?

Would this also benefit the miner as they now have an increased luck % on finding the next block with the random pool?

Assumption: List of pools contains at least 5 non-connected pools.


texts: How to dump all transaction from single bitcoin address?

texts:
How to get/dump/or download/curl request/ for all transaction from single address ??? I need info about txID's, scryptpubkeys, txinwitness and other deep info about transactions
Br.


texts:
If I put $50 into Mt. Gox in February 2013, made multiples trades from BTC to USD and back, always remaining in the Mt. Gox system, and then lost all of it in the March bankruptcy, how do I handle that for tax purposes?  Do I have to pay taxes on money I never had?

There's no record of transactions since the site has been shut down.


texts: What if a multibit classic private key is decrypted into garbled codes?

texts:
7 years ago I exported the multibit classic wallet and private key, both encrypted. Only remember the key password now. Problems occurred when I tried to decrypt the key in following ways:

installed MultiBit Classic 0.5.17 from web (might be dangerous).
Created a new wallet and tried "tools--import private key". Chose the old key, input the password and clicked "decrypt". The password seemed correct because there wasn't a fail note, which always appeared for other passwords.
Then, when I clicked "import private key", a fail note said "could not understand address in import file".
To compare I exported a new encrypted private key and followed steps above. It worked well. Though the new key had a wrong timestamp in 2014, it didn't hinder the import.

Used openssl in cmd to do direct decryption, found the only code:

openssl enc -d -p -aes-256-cbc -md md5 -a -in multibit.key  -out key.txt  -pass 'pass:myPassword'
that can decrypt the new key successfully. When decrypting the old key, it didn't show any error either, no "bad decryption". But the plain text was garbled like

?躠磱Q?39'ad"t鉼!?狡

_決[qp嗽雔紧鸘:?A濵彆r闞? &*绉i#唹B7鼞_z?

Tried lots of text-code-converter and they only gave different garbled text...
How would this happen? Was the old key exported incorrectly in 2013? Is there any hope?


texts: Bitcoin.text into Electrum issue with "0014" addresses

texts:
I am currently retrieving an old wallet. Which may have recieved btc from another wallet from around 2012/Be the old wallet.
While copying in to Electrum to create a new wallet using
Import bitcoin addresses and private keys
I found that almost half of my text file is filled with
0014xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 0 scrip
What is this?
Should i enter this, if so how?
The first part, After Extended private master key, is;
L3xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx etc
What should be the correct preface be to that line, when entered into Electrum.
One last question would be.
What exactly does "best block at time of backup" mean?


texts: As there are a couple endiannesses used by Bitcoin, what is the proper way to encode the data parameter for a getmemorypool JSON API call?


texts: How can I import the Mini Private Key of a physical coin?

texts:
I have a physical Litecoin based on a Casacius Bitcoin. I have the public key and see that the Litecoins are there.

Peeling back the seal/sticker revealed a Mini Private Key, but I'm having trouble importing it into Litecoin Core, importprivkey(…) gives me the error message Invalid private key encoding (code -5).

What do I need to do to import the Mini Private Key?


texts: How to set up a private bitcoin network with mining on a single machine?

texts: I created a testnet for mining using several ports in a single machine. However I see that the source codes [CAddrInfo, CAddr] are based on IP and not IP||port. Is there an easy change to make it do mining across ports [under same IP] or this is simply not possible?


texts: Which pooled mining scheme is better in terms of constant mining?

texts: I'm comparing gash.io with slush scheme. Say I mine 24x7 without pool hopping at 5GH/s. Will the BTC amount be the same if I mine at slush or gash.io. And what if I get disconnected from either of pools for say random one half hour duration or more a day, how would the reward be?


texts: Why is it insufficient funds when sending coins via datacoind when I have enough?

texts:
I'm trying to send my coins from my daemon I installed in my server. Its datacoind, but I'm guessing its the same as bitcoind. Is that a correct assumption?

http://prntscr.com/2h4eex

root@x:~# datacoind listaccounts
{
    "" : 11.43010363,
    "pat" : 0.00000000,
    "pats" : -0.45000000
}
root@x:~# datacoind sendtoaddress DJKrNvrnuuTsvuwThYfjP2Mo 7 "testing this out"
error: {"code":-4,"message":"Insufficient funds"}
root@x:~#


texts: Why is the Block Header txn_count field always zero?

texts: According to the Protocol Specification, the txn_count field of a Block Header is always set to 0, why is that? What are the intended future uses of this field?


texts:
I am using PHP cURL to generate new address from coinbase. As per this documentation we get notification on the callback url when any transaction is made on the generated address. But I am not getting any callback from coinbase when I receive any payment.

I want to achieve the following:

Generate a bitcoin address
Store the the generated address & the amount with it's user who paid it.

I am facing the problem in getting callback. I get payment in the coinbase & email saying that you received this amount etc., but no callbacks.

Also please suggest me that whether the coinbase is secure or not.
If not, what should I go for? I want to get the above things done.


texts: Are multibit HD (or other no web wallet) and Blockchain.info wallet words compatible?

texts:
Well the title says it. I tried to enter blockchain.info seed words into multibit, but it doesn't seem to be working.

So what I'm trying to do is to have multibit (or other) alternative of my blockchain.info wallet so I can send bitcoins when blockchain.info is down.


texts: I have a txt file labelled private key, inside is what i assume to be base64 string ending with =, is there any way I can access the wallet I assume this is the private key for?


texts: How to find a BTC/BCC mining node with modified software?

texts:
I want to confirm my non-standard transaction(s) in BTC/BCC network. To do it I have to find mining node with modified software. Is there pool admin who can switch off SCRIPT_VERIFY_CLEANSTACK flag on his node?

A special message to mods: this question is strong bitcoin-related. This is not looking for particular software :))

Update: one example is here: https://www.reddit.com/r/Bitcoin/comments/6f877c/ This trick will permit to spend funds from https://blockchain.info/address/3DkVqK1rUPZuj8EnPAbKmJ3A8xuZeTseeW in BTC-chain or http://blockdozer.com/insight/address/3DkVqK1rUPZuj8EnPAbKmJ3A8xuZeTseeW in BCC/BCH-chain

If you are interested in it I can publish the spending transaction.


texts: The only wallet I can find for Ripple is the standard web client. I don't like the idea of always having to trust a web client with my keys. Is there a local-only client for the Ripple network? If not, is there something preventing a local client from being developed or has it just not got enough interest yet?


texts:
Can you explain me in detail, what affect the price on BTC-e ? I understand the mechanic, like if there is strong demand and limited supply the price goes up. But how does it work on BTC-e? Because to me it looks like the website is setting the price itself. There are lowest and highest ask prices.

Thanks


texts: Bitcoin core does not have all unconfirmed transactions

texts:
I am running bitcoinqt and checking for new transaction for payments I made using getrawmempool. Payments were made NOT from/to the mentioned bitcoinqt wallet address.

As I see some my unconfirmed transactions never come to getrawmempool.

Is it expected result or I am doing something wrong?


texts:
I want to test Solo mining on OS X with Diablo Miner, so I pass options:

./DiabloMiner-OSX.sh -u my_user -p my_pass -r 8332

and I get:

[5/1/13 11:01:37 PM] Started
[5/1/13 11:01:37 PM] Connecting to: http://localhost:8332/
[5/1/13 11:01:37 PM] Using Apple OpenCL 1.1 (Aug 10 2012 19:59:48)
[5/1/13 11:01:38 PM] Added GeForce 9600M GT (#1) (4 CU, local work size of 512)
[5/1/13 11:01:38 PM] ERROR: Cannot connect to localhost: Connection refused
[5/1/13 11:01:38 PM] Added GeForce 9400M (#2) (2 CU, local work size of 512)
[5/1/13 11:01:38 PM] ERROR: Cannot connect to localhost: Connection refused
[5/1/13 11:01:38 PM] ERROR: Cannot connect to localhost: Connection refused
[5/1/13 11:01:39 PM] ERROR: Cannot connect to localhost: Connection refused

What could be the reason for this error?


texts: How do I claim bitcoin from an old wallet?

texts:
at my Blockchain "Bitcoin Address" page, it shows "Unspent Outputs":
Summary:
Address, Hash 160, Tools and
Transactions:
No. Transactions, Total Received and Final Balance. (I HAVE 0.4 FINAL BALANCE OF BITCOIN).

Then a REQUEST PAYMENT button.

I have some Bitcoins (0.4) in the Final Balance of "Unspent Outputs".
I used this back in 2016.
Today, 9th November, 2017 i opened a Blockchain Wallet for the first time.
It says i have a $0 balance.

My question is, how do i transfer this balance (0.4) to my Blockchain Wallet.

Any help would be greatly appreciated.

regards
Kel.


texts: Bandwidth required for Bitcoin going global?

texts:
Something that I feel might be the obstacle against Bitcoin going global -- but which I've never seen anyone mention -- is this:

If Bitcoin goes global, I think it's possible that the number of transactions per second will be so high that it will become impossible to download the block chain at typical internet speeds -- it will grow faster than it can be downloaded.

What I'm wondering is: is this a real possibility? If so, how might Bitcoin deal with it?


texts: Where to reliably buy Bitcoins via PaySafeCard?

texts:
Where to buy Bitcoins in a serious way via PaySafeCard? I do not like to name my account data or credit card data...

I want to use a method to buy safely and anonymously.


texts: Are there any services offering blockchain.info-like API for multiple currencies?

texts: I am wondering whether there are any services that offer some API like blockchain.info does but for multiple currencies at the same time. I know there are a lot of block explorers out there, but they appear to be disjointed and focused on one currency at a time.


texts: I've just recently started litecoin mining on a kind of old AMD GPU.  My motherboard has space for 2 additional cards.  I'd like to drop in a new card specifically for litecoin mining, but...  I'm not sure if the two cards need to be identical.  Crossfire stuff is confusing me.  If I drop in a second card can it be top of the line and still have my old card do some work?


texts: Why include the Segregated Witness Merkle Root in the input field of the coinbase transaction?

texts:
I just read this article to understand SegWit better: https://bitcoinmagazine.com/articles/segregated-witness-part-how-a-clever-hack-could-significantly-increase-bitcoin-s-potential-1450553618/ There's a part that doesn't quite make sense to me:

But there is one problem: If signatures have no effect on the makeup of the blockchain, the blockchain no longer serves as proof that the correct signatures were included in transactions.
To make sure that signatures are embedded in the blockchain regardless, a Segregated Witness-enabled miner adds a trick, too. Rather than creating only a Merkle Tree out of all of the transactions, it also creates a Merkle Tree out of all Segregated Witnesses, to mirror the transaction tree. The Segregated Witness Merkle Root, then, is included in the input field of the coinbase transaction. As such the Segregated Witness Merkle Root changes the transaction data of the coinbase transaction, its transaction ID, therefore influences the block header and, ultimately, the makeup of the blockchain.

Is this accurate? If so, what exactly does it achieve?
Including the merkle root of the transactions in the block header prevents tampering with the transaction list, but I don't see any value in tampering with the signatures.


texts: Theoretical minimum # of logic operations to perform double iterated SHA256?

texts: What is the theoretical minimum number of logical operations an ASIC needs to perform to compute double iterated SHA256, i.e., sha(sha(•))?


texts:
my litecoin wallet (shared 2 of 2) on electrum-ltc generated an address to receive LTC. I transfered some LTC to that address and tried to check in block explorer. Unfortunately got such message:
Sorry, 'ltc1qy4rwhdkujk35ga26774gqmng67kgggtqnsx9vp0xgzp3wz3yjkhqashszw' is not a valid LTC address, wallet name, transaction or block.

Is it something wrong with my LTC address? Electrum-ltc v 3.1.3.1. From what I know it is Bech32 Segwit address.


texts: What is the variable in a block that holds hash of found PoW?

texts:
Can anyone please tell me, which variable holds the hash of the solution of block's PoW in broadcasted block?
I know that a block consists of (I am pretty sure I am forgetting some variables here):

Magic no
Block size
Transactions (raw)
Transactions counter
Block header

version
hash of previous block
timestamp
bits
nnonce
hash(MerkleRoot)

So basically, my question is which variable holds the hash of solution of current block's PoW?
Thanks in advance.


texts: Has Apple stated its view on legality of apps using alternative electronic payment systems?

texts:
An article entitled "Why Apple is Afraid of Bitcoin" discusses Apple's interest in online payments. It also talks about the removal of 2 Bitcoin apps, Blockchain Wallet and BitPak, from the appstore.

  The explanation given by Apple was that “apps must comply with all
  legal requirements in any location where they are made available to
  users.” Apple further stated, “it is the developer’s obligation to
  understand and conform to all local laws” and the developer was
  referred to the legal department for an exact explanation of which law
  it violates. Clearly, they will not be able to cite a law as no laws
  prohibiting bitcoin currently exist in any jurisdiction.

Though the author of the article claims that no laws prohibit Bitcoin, Apple obviously disagrees but was very unhelpful in explaining which law it might be referring to. Has Apple discussed its stance regarding legality of apps using Bitcoin or other alternative payment systems?


texts: What is the difference between the two types of Blockchain.com wallet?

texts:
Really new to cryptocurency so bear with me.
I am currently using Bockchain to store the Bitcoin. But, what is the difference between "My Bitcoin Trading wallet" and "My Bitcoin Wallet"?
Also, what software do I use to start mining coins like Bitcoin or Ether?


texts:
I installed electrum a while back and noted down the 12 word seed. Haven't used it for a few months, but now when I go to view my seed (clicking on the seed icon on the bottom right of the GUI), it asks for my password, and then the dialogue says:

"Your wallet generation seed is:"

And the text box below is completely empty, underneath which it says:

"Please write down or memorize these 0 words (order is important)..."

A bit concerned my seed seems to have vanished. Any suggestions?


texts: I heard that the recommended waiting confirmation time for a bitcoin transaction is 6 blocks/ 1 hour. So a shop which lets its customer to pay in bitcoin without any waiting for confirmation would risk double spending from the side of the customer. Is this a big hindrance for bitcoin (cryptocurrency) real-life usage? If yes are there any solutions, improvements? Thank you.


texts: BitCoin API C# - can I create transaction, add IO, sign, get hex?

texts:
I am using this link as a demonstration of what I want to achieve (see code below).

I am not in a position to use node.js now - and I need to use C#.

I have looked at the bitcoin.info API

My Question: would the C# BitCoin API be able to do the same where I build up the transaction, add the inputs, add the output, sign the transaction and then get the hex?

Is there sample code that someone can refer me to please?

var bitcoin = require('bitcoinjs-lib')

var tx = new bitcoin.Transaction()

// Add the input (who is paying) of the form [previous transaction hash, index of the output to use]
tx.addInput("aa94ab02c182214f090e99a0d57021caffd0f195a81c24602b1028b130b63e31", 0)

// Add the output (who to pay to) of the form [payee's address, amount in satoshis]
tx.addOutput("THEADDRESS", 15000)

// Initialize a private key using WIF
key = bitcoin.ECKey.fromWIF("L1uyy5qTuGrVXrmrsvHWHgVzW9kKdrp27wBC7Vs6nZDTF2BRUVwy")

// Sign the first input with the new key
tx.sign(0, key)

// Print transaction serialized as hex
console.log(tx.toHex())
// => 0100000001313eb630b128102b60241ca895f1d0ffca2170d5a0990e094f2182c102ab94aa000000008a47304402200169f1f844936dc60df54e812345f5dd3e6681fea52e33c25154ad9cc23a330402204381ed8e73d74a95b15f312f33d5a0072c7a12dd6c3294df6e8efbe4aff27426014104e75628573696aed32d7656fb35e9c71ea08eb6492837e13d2662b9a36821d0fff992692fd14d74fdec20fae29128ba12653249cbeef521fc5eba84dde0689f27ffffffff01983a0000000000001976a914ad618cf4333b3b248f9744e8e81db2964d0ae39788ac00000000

// You could now push the transaction onto the Bitcoin network manually (see https://blockchain.info/pushtx)


texts: Why was my full node knocked off the network last night?

texts:
Any idea what happened last night that caused my full node to fail with messages like this:   (full log available upon request)

2017-09-25 21:15:59 Bitcoin version v0.15.0.1
...

2017-09-25 21:32:33 UpdateTip: new best=00000000000000000079fb649dd2c7e35978bd6d7922b8661c1e3ae597f24191 height=486858 version=0x20000002 log2_work=87.166038 tx=256852323 date='2017-09-25 03:51:56' progress=0.999233 cache=370.8MiB(2762033txo) warning='2 of last 100 blocks have unexpected version'
...
2017-09-26 13:32:19 receive version message: /bitcoin-seeder:0.01/: version 60000, blocks=350000, us=108.196.200.233:8333, peer=2183
2017-09-26 13:32:52 receive version message: /Bitcoin ABC:0.14.4(EB8.0)/: version 70015, blocks=489424, us=108.196.200.233:8333, peer=2184
2017-09-26 13:32:55 ERROR: AcceptBlockHeader: Consensus::ContextualCheckBlockHeader: 000000000000000000639be19a0123a1c99d9fef89f0b8ac055a77f4ef86ae3b, bad-diffbits, incorrect proof of work (code 16)
2017-09-26 13:32:55 Misbehaving: 10.32.0.1:55716 peer=2184 (0 -> 100) BAN THRESHOLD EXCEEDED
2017-09-26 13:32:55 ERROR: invalid header received
2017-09-26 13:32:55 ProcessMessages(headers, 162003 bytes) FAILED peer=2184
2017-09-26 13:32:55 connection from 10.32.0.1:46684 dropped (banned)
2017-09-26 13:32:59 connection from 10.32.0.1:47442 dropped (banned)
2017-09-26 13:33:00 connection from 10.32.0.1:50695 dropped (banned)
2017-09-26 13:33:00 connection from 10.32.0.1:49700 dropped (banned)
2017-09-26 13:33:02 connection from 10.32.0.1:15754 dropped (banned)
2017-09-26 13:33:03 connection from 10.32.0.1:47560 dropped (banned)
...
...

At this point my node was seen as "down" by https://bitnodes.21.co/
Today, it appears to be working normally again.


texts: I have Bitcoin on an old version on the Bitcoin app; more specifically Bitcoin.org version 0.3.22. I tried to transfer the Coins to a newer wallet, but they don't go through. has anyone had or worked around this issue before? Thank you!


texts: Is it possible to reverse a confirmed transaction?

texts: I have been scammed by a so-called "trading account manager", he kept stalling until he told me my account had a problem and needed to be "rectified". Then, he told me I had to pay $300 for that, so I'm seek help to regain my funds.


texts: Freebsd Bitcoind doesn't read config correctly

texts:
When I try to connect to my bitcoind server with the username and password in my bitcoin.conf I get a 401 error.
When I set an username and password in the bitcoind parameters(bitcoind -rpcuser=... -rpcpassword=... -daemon) it does work.

I also have prune in my config file. For some reason this does work.
Also the rpcallow works fine.
So it does read my config file?

When I add the -conf parameter with my config file I get this error:

Error reading configuration file: the options configuration file contains an invalid line '��
(I also can't read those last 2 characters)

I even get this error when the file is empty

Does someone know how I can fix this?


texts: Sending Bitcoin between paper wallet and hardware wallet offline

texts: Good morning, I'm just beginning this journey into crypto currencies. Right now, I've got my Bitcoin in a wallet at Coinbase.  I'd like to keep my Bitcoin in a paper wallet. I think from Coinbase to my paper wallet is pretty straight forward.  I need my paper wallet's public key and send the Bitcoin from Coinbase to the Paper Wallet. So now I go on line and buy something with my Bitcoin. I'd like to transfer just the amount of my purchase from the paper wallet to a hardware wallet while off line and then connect the hardware wallet to the internet to complete a purchase. I'm thinking this would be the way to keep my money safe from hackers. Am I able to do this?  Thank you so much in advance for any help.


texts: Properties of Bitcoin as an Electronic Cash System

texts:
I am studying the concept of Electronic Cash, and in several reference I found that the criteria describing the ideal electronic cash system are as follows:

Independence: The security of electronic cash cannot depend on
any physical condition. Then the cash can be transferred through
networks.
Security: The ability to copy (reuse) and forge the cash must be
prevented.
Privacy (Untraceability): The privacy of the user should be
protected. That is, the relationship between the user and his
purchases must be untraceable by anyone.
Off-line payment: When a user pay the electronic cash to a shop,
the procedure between the user and the shop should be executed in an
off-line manner. That is, the shop does not need to be linked to the
host in user’s payment procedure.
Transferability: The cash can be transfered to other users.
Dividability: One issued piece of cash worth value C (dollars)
can be subdivided into many pieces such that each subdivided piece
is worth any desired value less than C and the total value of all
pieces is equivalent to C.

Now, what of the above properties are achieved by the Bitcoin system? I guess 1, 2 and 5 are trivially achieved, and I think 3 and 6 are not fully achieved. I wonder if 4 is achieved, and I'm particularly interested in this off-line property.


texts: Would moving a transaction from an old block to a new one allow more pruning?

texts:
At Pruning the branches in Merkle Tree Nick ODell writes "A leaf (transaction) can be pruned when all of its outputs have been spent." So I was thinking that if a transaction is one of the last few in a block, a miner can copy the transaction into the new block being mined.  That way the miner (and the rest of the network) no longer needs that block for validation, and it can be release into the ether.

Nick also wrote that Bitcoin core won't prune that way anyway because it operates "on the assumption that you download and validate all blocks."  I am exploring the reasons for this to see if they can be addressed without keeping everything.

The idea behind downloading the entire blockchain before starting pruning mode is that you want to make sure what you start with is valid.  The only known way to do that is to get the whole thing.  Or is it?  It seems that the ubiquity of the blockchain itself is matched by the ubiquity of the valid UTXO set, so if you get a valid UTXO set and it matches what every other node says, you're good to go.  Except for Sybil attacks, right?  Would such a successful Sybil attack also allow the blockchain itself to be faked?

One difficulty with my move-a-transaction approach is that when a new node is downloading the blockchain (however much of it is still needed) it will want to verify each block, and if block X is missing, then all the blocks that contain inputs that were created in block X can't be validated, if that means validating that the transactions in it are valid.  However, the blockheader itself can still be validated.  Block X's header can't be validated because it's contents are missing.  But isn't the fact that the hash from block X is required in block X+1 enough to trust that block X was valid, and that, therefore, so are blocks X+1, X+2, X+3, etc., all the way up to and including whatever block-being-validated contains a transaction that uses an output (presumably) created in block X?

When a transaction finally shows up that does spend an unspent output from the moved transaction, it won't be possible to validate it because block X is missing.  However, if the index that identifies which block holds which transaction were updated by the miner who moves the transaction, then this is simple to solve.

Would that index-update have to address all the immediate-child transactions of the moved transactions as well so that existing, previously valid transactions could still be validated by finding the source transaction in the newly mined block?  I don't think it's necessary to re-validate transactions that are in blocks with validated headers, is it?


texts: Public Key VS Wallet Address - What is the difference?

texts:
I am seeing a lot of contradictory information on why we now use Wallet Addresses rather than Public Keys.

Some say that due to additional level of hashing (double hashing), Wallet addresses are harder to crack, making them virtually quantum computing resistant.

But then others are saying that public keys are always being added into the script of every transaction, making the additional layer of security irrelevant.

My question is, why are we using wallet addresses now, when transacting?


texts: Which cryptocurrency has the smallest block time?

texts:
What is the lowest block time of any cryptocurrency? I don't mean the time of an individual block, but the target time per block.

What is the shortest reasonable block interval?


texts: What is the easiest way (user experience wise) to get xpub?

texts:
I'v got monitoring app going for my hardware wallet and am planning to release it to public. Biggest pain point right now is asking users to enter their xpub key. It can be done, but there is no decent documentation online and every big hardware wallet company has their own explanation in FAQ.

I'm trying to figure out if there is an easier more unified way to access xpub address be it for ledger nano s, trezor, keep key or any other wallet?


texts: Fully synced bitcoind 0.18.1 on RPI4 using 100% cpu ( 1 core only ) , is it normal?

texts:
I started playing with bitcoind 0.18.1 on a RPI4 and i can see that even when fully synced it is still using 100% cpu so one full core.

Is this normal / expected ?

Looking at the threads is the bitcoin-msghand (ler?) thread that is doing the work

 5946 999       20   0  557016 410080   3392 R  98.8  10.2 226:58.92 bitcoin-msghand

could it be that my dbcache=100 is causing it to do much IO while relaying data to other peers ?
To be fair i don't see much IO at all

thanks!


texts:
Is the main network address version for zcash already known? Is it possible to generate a mainnet address already?

This could allow miners to start from minute 0 to mine on a anonymous pool. The addresses can exist without the network as they are just a cryptographic keypair.

I checked the chain params at the source repository.

It looks like t-type addresses start with t1, and multisig with t3.

// guarantees the first 2 characters, when base58 encoded, are "t1"
base58Prefixes[PUBKEY_ADDRESS]     = {0x1C,0xB8};
// guarantees the first 2 characters, when base58 encoded, are "t3"
base58Prefixes[SCRIPT_ADDRESS]     = {0x1C,0xBD};

And from the protocol:

  In Bitcoin a single byte is used for the version field identifying the address type. In Zcash two bytes are used. For addresses on the production network, this and the encoded length cause the first two characters of the Base58Check encoding to be fixed as “ t3 ” for P2SH addresses, and as “ t1 ” for P2PKH addresses. (This does not imply that a transparent Zcash address can be parsed identically to a Bitcoin address just by removing the “ t ”.)

But how to generate them? Never seen dual prefixes berfore. Also, what's the address version? My vanitygen is unable to cope.


texts: Is the current network difficulty algorithm appropriate for "Peak transaction-only mining"?

texts:
At some point in the future miners will depend more on the Tx fee than per-block payout.

Right now people turn on and off their equipment based on local trends such as price of electricity, etc.  On the whole I don't think these local decisions affect mining as a whole.   However, if a Global trend is identified and people turn off and turn off the rigs accordingly then that will weaken the network at certain times.

Suppose the most profitable Tx fees occur in a certain time of day, and people will turn on their mining rigs, and they shut it down for less efficient hours.

  I think that if done to a significant scale, "peak Tx mining" can cause issues in security and network security.

Question

If the purpose of difficulty is to make mining new blocks more consistent over time, is it equally effective in making Tx-based payouts fair with short intervals?

More detail

Suppose significant portion of the mining ecosystem determines that the most valuable transactions are mined between 4pm and 5pm EST where the most profit can be made.  Conversely it's not profitable at all to mine at 2am-5am EST, so shut the machine down and save on electricity.

This may result in several things

Difficulty for peak hashrate differs greatly from difficulty for non-peak hashrate (within a 24 hour period)
Certain times of day where the network is more likely to be overtaken by hostile compute power
Unfair /disproportionate distribution of fees among miners
Many more blocks are created at peak times due to the increased available hashpower

What safety nets are there to protect against this?

For what it's worth, the BitMinter client already has the ability to schedule the usage of mining resources.  The intention is for minimizing local electricity cost, I don't think that would have a negative impact since this is a global mining network and electricity price changes occur every hour and should even itself out.  Conversely if it is used to mine according to trends in the whole Bitcoin network... I think that could lead to negative consequences.


texts: Cannot do anything at all with Bitcoin in my Blockchain.info wallet

texts:
Blockchain support is useless, have had a couple of (small) transactions pending since November that will seemingly never get dropped or confirmed.

Whenever I try to send anything at all, from any device and with any fee, I get this:

× Close
BitcoindException(super=com.neemre.btcdcli4j.core.BitcoindException: Error #-26: 66: mempool min fee not met, code=-26)

Coinify sell orders don't work at all either so my "money" is literally irretrievable.


texts: Do full-nodes process all transactions before broadcasting the new block header?

texts:
If so, why not do it after (re)broadcast? I think it would cut down on lag time.

Since the node would still validate the PoW and the previousblockhash, it would not be possible to DoS the network with invalid headers
Miners could begin processing the candidate block from its header and the list of transaction hashes since they already likely have > 90% of those txs.
Miners and full-nodes would still only update their head once all the txs are validated.
Miners could determine how much time (=money) they are losing by comparing the time they receive the header and the last tx.


texts: Would an increased blocksize lower the stress of the stress tests?

texts:
I see that there are about 9000 unconfirmed transactions right now and that five of the last six blocks are under 1/2 Mb and 15 blocks in a row under 750 Kb.  This suggests to me that larger block sizes would not help alleviate the backlog of unconfirmed transactions.  For whatever reason (probably low transaction fees), miners are not including a lot available transactions.

Am I misinterpreting the data?


texts: How often do I need to backup my Copay wallet? Is a new backup after every transaction necessary?

texts:
Is it true that I need to make a backup after each time an amount was sent from a wallet by writing down the 12 words?

Unfortunately, I had Copay and saved only before the transaction was sent, and now I can not get back the remaining amount.


texts:
I keep hearing "buy the dip" constantly with Bitcoin people/comments.
I get that it means that you should buy Bitcoin while the price is temporarily low, but what do they mean by it? Do they assume that people have a bunch of money just sitting around waiting to be spent? If they have the ability to buy Bitcoin, and they have money, why would they not have already done so, and thus have no money to spare?
Am I just unique in that I don't have any massive streams of income constantly flowing into my bank account for me to "buy the dip"? For me to afford a single small purchase on Bisq, I'd need about $500, which translates to several full months of me saving all the money I don't absolutely need. To buy a little BTC once. And then my bank account is drained again, and I have to start over saving for months to make another such minor purchase.
What do they mean by "buying the dip"? Do people normally have enormous amounts of money piled up just "waiting for the right time to invest"? Are they deliberately acting arrogantly as to pretend that they are super rich and assume that everyone else also is? Do they genuinely not understand that others aren't as super-rich as they are? I don't understand it.


texts:
I want to fetch transactions for an address from the following api:

https://blockchain.info/address/$btc_address?format=json

The thing is understanding the json returned from the api, I don't understand which of them are the transaction and the time when that transaction took place and the confirmations of a transaction.

Can any one help?


texts: I don't have enough knowledge pertaining to the Bitcoin mechanism. Can Bitcoin help people commit money laundering?


texts: any website tracking history of circulating tokens of any coin?

texts:
Is there any website dedicated to tracking history of circulating tokens of any coin?

Ideally, for each time a crypto has tokens added or removed to its circulating amount, we'd want to know:

amount
exact date
sent to whom (even if burnt, we want the address)

I am currently writing an analysis about many different coins and found this information incredibly hard to get (in most cases).

Token distribution is the base so I would expect a website or sort of organization dedicated to this task, but maybe I'm wrong.


texts: Is there any open source implementation of Litecoin wallet integration in Java?

texts: I want to integrate Litecoin wallet.Is there any way to do it


texts: How to connect to several Bitcoin nodes using Bitcoin

texts:
I'm looking for a way to connect to several Bitcoin nodes using Python...
I've been looking in different Bitcoin-for-Python libraries, but I haven't found anything :(
What should I do?


texts: Why is the length of the transport messages on the lightning network encrypted?

texts:
From BOLT 08 we can see that every message is sent in the following way:

2 byte: length
16 byte: MAC
[length] byte: Encrypted message
16 byte: MAC

In reality these messages will be send over TCP/IP on the internet. The ip header specifies the length of the data package that is being sent. If we extract the length and subtract 34 byte for the header plus the two MACs we would know how long the message is.

Is the idea to always send a 2^16 byte ip package and fill the rest with junk data? If yes why isn't that specified in the BOLTs? If no: why encrypting the length anyway?

I assume that an attacker would be able track all tcp/ip packages on the lightning port and would at least be able to deduct which messages are being sent even though the messages themselves are safe.

Assume the message length can indeed be deduced can't that be used together with the MAC to reconstruct the session key for that message?


texts: multibit isnt showing my bitcoin as spendable

texts: I sent some btc to my multibit wallet a while back to try out the software.  multibit tells me that the transaction has only been seen by 4 peers since 21 may 2013. however blockchain.info tells me confirmed by 36840 peers. the part of my transaction shows unspent bitcoin. how do i get multibit to see my bitcoin as a valid transaction and allow me to spend some or recover it in a blockchain.info wallet?


texts: How is the Elements Project's pegged sidechains concept similar to and different from the Lightning Network's payment channels concept?


texts:
What is the difference between BFGMiner and CGMiner in Laymen's terms?

Also, the longterm outcome will be exactly the same if mining is done with or without a pool, correct?


texts: How to tell how many hashes/sec the bitcoin core app on osx is running?

texts:
I'm curious how many hashes per sec my cpu is able to perform, is there some way to check this?

This is a follow-up to this question.


texts: Is it possible to have complete cold storage in NXT?

texts:
BTC has capability to create new account on offline computer and send some coins to and from that account without ever going online.

Sending coins to that account is trivial.
Sending from that account is done by generating transaction on offline computer, saving it on flash drive or CD, inserting that media into online computer and feeding transaction to the network.

That way I can keep large chunk of my coins on my offline computer without worrying about keyloggers. Even if they got there during installation they won't be able to send anything because it's offline. The only thing they can do is corrupt my data, which is solved by backing keys up on another flash drive or CD.

Does such possibility exist in NXT ?

Unlike BTC, new NXT account has to send at least one outgoing transaction to become fully initialized by the network, otherwise collisions may spoil it. Sending money to that account is not sufficient for initialization.

Can I generate and save and feed transaction in NXT like in BTC ?

If not then how am I supposed to initialize my offline NXT account without giving my password to online computer that may have keyloggers, viruses, NSA bots and whatever else runs on it ?

Is it possible to initialize NXT account with authorization token generated offline ?

Is it possible to send money or message or buy alias or participate in distributed exchange using authorization token or some other way generated offline ?

Does NXT have that feature in it's plans ?


texts:
Suppose I buy 1 bitcoin on unocoin at 174,000.
Now I see that the selling price on unocoin is 160,000 and selling price on coinsecure is 170,100.
So can I sell my bitcoin on coinsecure directly?


texts: ncdns uses the wrong nameserver to resolve .bit domain

texts:
Basically, I'm setting up a .bit domain for my blog.  I have registered a domain using namecoin, and given it a nameserver entry on the blockchain:

$ namecoin-cli name_show d/aoeu2code
{
  "name": "d/aoeu2code",
  "value": "{\"ns\": [\"ns.aoeu2code.com\"]}",
  "txid": "a49ad527f36fc41c47b8d743d376c3b011c7999dbf4d9da64afbdb3ccbdd8934",
  "vout": 1,
  "address": "NHE7a7xJF2XMQzCwg5PLggeTdZ3yQDvqmS",
  "height": 370929,
  "expires_in": 35991,
  "expired": false
}

The nameserver itself appears to be set up correctly.  When I dig for my .bit domain, the IP shows up as expected:

$ dig aoeu2code.bit @ns.aoeu2code.com

; <<>> DiG 9.10.3-P4-Debian <<>> aoeu2code.bit @ns.aoeu2code.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17650
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;aoeu2code.bit.                 IN      A

;; ANSWER SECTION:
aoeu2code.bit.          604800  IN      A       69.180.151.171

;; AUTHORITY SECTION:
aoeu2code.bit.          604800  IN      NS      ns.aoeu2code.com.

;; Query time: 1 msec
;; SERVER: 69.180.151.171#53(69.180.151.171)
;; WHEN: Sat Nov 18 01:30:58 CST 2017
;; MSG SIZE  rcvd: 88

However, when I try to resolve my .bit domain via ncdns, it does not try to use my nameserver, it uses a different one, ns.mydomain.com.mydomain.bit instead of ns.mydomain.com:

$ dig aoeu2code.bit @localhost -p 5300

; <<>> DiG 9.10.3-P4-Debian <<>> aoeu2code.bit @localhost -p 5300
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25963
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;aoeu2code.bit.                 IN      A

;; AUTHORITY SECTION:
aoeu2code.bit.          600     IN      NS      ns.aoeu2code.com.aoeu2code.bit.

;; Query time: 0 msec
;; SERVER: ::1#5300(::1)
;; WHEN: Sat Nov 18 01:24:44 CST 2017
;; MSG SIZE  rcvd: 73

BTW, I'd also like to be able to give myself coins on the testnet chain and run tests there, since I have been having a little bit of trouble obtaining namecoins.  I can run namecoind -testnet and namecoin-cli -getinfo shows my balance is 0, but other than that I have no clue how to use the testnet chain.


texts: Gaming the "off-by-one" bug (difficulty re-target based on 2015 instead of 2016 block time span)?

texts:
In this forum post from Gavin Andresen he writes:

  Second: I've written 'discourage blocks' infrastructure:
    https://github.com/gavinandresen/bitcoin-git/tree/discourageblocks
    (code reviews welcome)

  ... which should give us the ability to nudge miners to Do The Right
  Thing.  Discouraging blocks that appear to be gaming the off-by-one
  bug should be enough incentive to prevent 50+% cartels from forming,
  without requiring a blockchain-splitting change.

I believe the off-by-one bug refers to the difficulty re-target being based on the time taken for the previous 2015 blocks instead of 2016 blocks - please correct me if I'm wrong.

What I want to know is how can this bug be gamed by miners? What can they do and what advantage does it give them?


texts:
Somewhat new to bitcoin, trying to understand the tech...
For my understanding all the transactions go into a block, every 10 minutes the block is mined and all transactions in it are confirmed. With every block confirmed (meaning every 10 minutes) the older blocks get harder to hack. The blockchain algorithm knows to adjust its own difficulty so that every 10 minutes a block is mined. Is the above correct?

If it is then how come the scaling problem is block size and not block frequency? If the network can adjust it self to the compute power why not resolve a block every minute while decreasing the amount of BTC to be produced with every block and keeping block size at 1MB?

Thanks


texts: Why does hashing public keys not actually provide any quantum resistance?

texts: In the discussions about taproot, it was mentioned that outputs will include the public key directly instead of hashing them. It is stated that, currently, hashing does not really provide quantum resistance. Why is that?


texts: How can the alert system be triggered? Who can do it?

texts:
Since we established the alert system is included in the official client, I would like to know who can trigger the alert system, and how?

Can this system be spammed (activated 1000s times per second) thus disabling any use of the client? (Because he would get annoying popups all the time)


texts: If I have a segwit UTXO  with for example 10 BTC , can I make some raw transactions ready to get broadcasted?


texts: Why cant i retreive my BTH coins from my blockchain wallet

texts:
I logged into my wallet on blockchain.com today. I followed the links through and saw that I had been credited with a equivalent number of bitcoin cash coins that I had been expecting.

I had a few other things to do whilst there so did those first then when I went back to deal with the BTH coins they were no longer showing. what can I do to reclaim my BTH?

btw the other things I did were to move BTC from addresses into my wallet  I also backed up my wallet and recorded a new 12 word phrase but these shouldn't has had any bearing on my entitlement to BTH


texts: How to retrieve all transactions from a public address?

texts:
I run a Bitcoin node with txindex=1 so I can retrieve any transaction from the txId.
My question: if I have any public address, how can I retrieve all transactions involving this address (inputs and outputs) with the Bitcoin Core commands ?


texts: When does a blockchain fork resolution happen?

texts: I understand that forks are resolved by largest proof-of-work etc. but when do the miners decide to resolve a fork? Is it a question of network consensus or does each individual miner resolve at their own pace?


texts: What is the Lightning Network proposal? What problem is it trying to solve?

texts:
We already have a few questions about technical details of Lightning network, however, …

What is the Lightning network proposal in the first place?
What problem is it aiming to solve?


texts:
I have registered on https://sandbox.coinbase.com before, two days ago. They are showing me that I have received 100,000 bits.

It's been 3 days that status is still in pending state. What am I supposed to do?


texts: When we can agree on mempool sorting order, we can just confirm first n-transactions that are at least 10 mins old. What's missing?

texts:
When we can agree on a mempool sorting order, we can just confirm first n-transactions (or 80% of transactions) that are at least 10 minutes old.  Then, we can transfer (broadcast) the block header and a hash to the set of all confirmed transactions.

Just consider this as an aggressive version of BIP152, compact blocks.

This kind of method will work for transactions of any size; both confirming 10 transactions and 1 million transactions are the same.

What's missing? Why are we not doing 'confirmation' like this?

For example, if we have 1000 transactions in a mempool (sorted), 900 transactions are at least 10 minutes old, and we're confirming the first 720 transactions.

This may not be a perfect or complete solution, but we just need to find,

Sort order; fee, size, etc.
Transaction age; say, 10 min
Confirm size; say, confirm first 80%

Note:
Sort order is based on f(trxn-meta-data; fee, input, output, etc.), transaction age is used as a filter. Another filter is first x% of the set.


texts: MultiBit: I clicked on Close Wallet and now i don't find a wallet

texts:
Yesterday, I installed a multibit in my computer and i put some bitcoin in multibit. Some bitcoin put in other site, but a majority of bitcoin it stayed in wallet..
Today, I wanted to put password in my wallet, but i clicked in close wallet.. I was sad with this situation.. So, i was finding, but it didn't appear...

After to experiment, i created other account and if i closed that wallet, it appeared in open wallet....
However, i don't understand where it stays a wallet that disappeared.. what can i do? my address was 17VxARsZCpLYcqxcaaeZQDm6gxY6e1tyXx and it's my last transaction of my wallet: http://blockchain.info/pt/address/17VxARsZCpLYcqxcaaeZQDm6gxY6e1tyXx?filter=0

how can i recover my btc or my wallet?

sorry my english.
thanks for help..


texts: GDAX deposit accounts - what happens to addresses that change?

texts:
I sent a LTC transfer into a GDAX deposit account. I have done this before without any issues.

The transfer appears processing from the exchange I sent it and it still hasn't appeared in the block explorer, however when I check on GDAX, the deposit address changed. I did a test sending a small amount, and after seeing it went through repeated the transfer to the same address with a larger amount.

I cannot stop or modify the transfer out and would like to know what happens to the old GDAX deposit account?

Will the deposit be recognized by GDAX? Has anybody sent litecoin or bitcoin to a deposit account that had changed before sending?


texts: bitcoind.service problem showing a error message

texts:
it is giving this message
The unit bitcoind.service has entered the 'failed' state with result 'exit-code'.


texts: In 2009, where were Bitcoin source codes stored?

texts:
Now I can see the Bitcoin Core source code in Github but I wonder where the original source code of Bitcoin were stored back in 2009? Was it managed under SVN? How did contributors or programmers work together back then?

Thanks,
Pil


texts:
Blockchain.info shows a graph of transactions excluding "long chains" of more than 10: https://blockchain.info/charts/n-transactions-excluding-chains-longer-than-10

This seems to indicate that ~68% of all transactions in bitcoin are part of long chains (which just means they changed hands more than 10 times in a day).

Tumbling is mentioned as one reason these chains are created, but I would like to explore this deeper. What other reasons might long chains be created?

Would gambling create long chains? (continuing to send to a service that pays out sporadically to you and others)
Are there other examples where two parties would legitimately want to transact between each other rapidly on blockchain?
How often does tumbling create long chains? I'm not familiar with which services are popular and how many rounds are recommended.

It would be interesting to understand what is causing the popularity of long chains in bitcoin right now. Thanks!


texts:
The amount of bitcoin-like crypto currencies overwhelms me.

Just few minutes ago I came across FeatherCoin

The problem is that the information on the official site is scarce and the only thing I was able to understand is that the difference from litecoin is the block reward and the total amount of coins.

What is the point of this?


texts: How could a decentralized network limit the amount of nodes to one per user

texts:
Proof of Elapsed Time seems like a great idea to me, but in fully decentralized and public networks (like one similar to bitcoin) this would bring problems with it as one could just put up as many nodes as they like to heavily increase their chance of mining a block.
Is there any way to limit the amount of nodes a 'user' could run to 1?
Are there any solutions to this problem?
But the first problem would probably be defining what one 'user' is


texts: What does the Sender of a Transaction include in the Input that allows the Recipient to Unlock/Redeem?

texts:
I have been struggling to grasp what exactly is included in the input of a Transaction that allows the intended recipient to then redeem/unlock that UTXO when they are ready to do so.

I understand that a transaction contains a Digital Signature created by the Senders Private Key on the message.

I become confused when trying to understand what data the sender includes in the Transaction that allows the recipient to unlock that UTXO and turn it into a subsequent input when they choose to do so. Is the Sender including the Recipients Public Key in the Transaction allowing them to use a scriptSig to unlock that UTXO?

Thanks for taking the time out help


texts:
How To Run Litecoin Node? I want to run my own litecoin node like bitcoin
  I know how to run bitcoin node but there is some issue when i am starting litecoin node

Any Idea? #Creating Litecoin Configuration File (litecoin.conf) and installing dependencies to run litecoin full node


texts: What are the difference between a segwit and legacy wallet

texts: I am installing a mobile wallet and it ask me what type of address I want to use, I want to try and use a segwit address but is there a risk that my coins will be lost if I try to transfer fund from an exchange if they dont support it, or if I want to transfer coins from my segwit address to a legacy one.


texts:
Of course, the function of mining is to secure the blockchain, but I'm looking for a more abstract summary of what the exact problem is that mining tries to solve? I believe its called the Byzantine Generals problem, but can it be described in a couple of sentences?

The network needs to select one random stranger out of a large group at a fixed schedule, and uses a 'hashing-lottery' as a reasonably fair method to do so. Is that a good definition of the reason why POW is needed?

In other words: Suppose I developed an alternative method to select a random p2p node every few minutes, who gets to publish the next block, could that replace cpu-based proof of work?


texts: Ledger: is the private key tied to the device or the wallet?

texts:
Context: I have a Nano S since before, with one recovery phrase and a wallet with some minor BTC on it. Bought a Nano X, set up with a new phrase, and a new wallet, and put some coins in that. Then I imported the old wallet to the new device as well via Ledger Live, so there's two wallets. But then I started wondering:
Is the recovery phrase per device or wallet, or how does it work? If someone gets my old phrase, can they unlock my new device as well, or can they only unlock the old wallet?
It seems it would be possible to unlock the old wallet with either the new or old phrases, but the new wallet only with the new phrase?
Been scouring through the docs but it doesn't really say how this works. I guess when I imported, it should have regenerated that same old wallet but with new keys? But would want to be sure.
Not too worried about the old wallet, but the new. So if someone still can recover only the old one, I would not care that much, but is my new wallet on both phrases somehow I guess is my question, or is it only on my new Nano X devices phrase?


texts: Is there a Bitcoin bank, which gives interest on my deposit?

texts: Is there any Bitcoin bank I can place my Bitcoins in that will give me a decent interest rate. It should be at least 1% for it to be worth it.


texts: What is the meaning and application of the apostrophes in derivation paths of BIP32 / BIP44?

texts:
Can we please clarify if there is any difference (because apparently some technical documentation explicitly requests to include apostrophes) between a derivation from extended private key (xprv) or public key (xpub) of a child subkey, where m = root (xprv or xpub).

m/44/0/0/0 and  m/44'/0'/0'/0

What are the meaning of the apostrophes and how / when should they be applied? Do they change anything in a derivation path -- will the derived child subkey be different with or without them?


texts: Turnkey Bitcoin test clone for demonstration purpose

texts:
So I'd like to demonstrate a blockchain based digital currency within my firm. For various reasons, I can't just use bitcoin (or of course I would).

I also can't distribute pc exes, hence the requirement for a web based wallet. Security does not need to be paramount. There does not need to be a competition for mining although mining does need to be a component (ie there will probably be just one miner running on one cpu / low priority).

Is there an open source web wallet and counterpart configurable mining system ? I took a quick look at coinpunk but I'm not sure that is still supported / running (last update almost a year ago, website offline?).

All suggestions gratefully received.


texts: I accidentally sent my BTC to a BCC address. Is there a way to recover them? Is there somebody that can help me with this matter? If there is a charge to recover my coins, I will pay for it.


texts: Is difficult hashing algorithm necessary?

texts: To avoid GPU/ASIC mining, difficult hashing functions, such as scrypt and scrypt-jane, are proposed as PoW algorithm (However, GPU and ASIC are also suitable for basic scrypt operation). Is it good for the cryptocurrency? Because a difficult algorithm also means CPU needs to spend much more time to find the solution. Although the "difficulty" of the cryptocurrency is dynamic and adjustable, maybe one day a very complicated algorithm scrypt-xXx is proposed, it might be hard to find the nonce even when the difficulty is very low. Will it create some problems to the cryptocurrency?


texts: Would appreciate some help getting datadir parameter to work in Linux Mint 19.2

texts:
I am trying to use Bitcoin Core 0.18.1 on Linux Mint 19.2. I have previously used an older version on Win7 with no problems.

I have moved my old data directory to a new ext4 partition on an internal hdd. Bitcoin is installed on internal ssd. Everything was fine using default /home/admin1/.var/app/org.bitcoincore.bitcoin-qt/data/.

I cannot get the datadir parameter to work (-datadir=/mnt/WDRED/BitcoinData/). It keeps saying the folder does not exist. I tried deleting the default data folder and replacing it with a symlink to the actual folder on hdd but it says the same thing that the symlink folder does not exist.

Somebody might tell me ultimately I have done something stupid or I should have been able to figure it out myself but I have tried what I could from reading up and I am frustrated now. Thank you.

EDIT----

I have now solved the problem hopefully. I installed bitcoin core from within the native software manager in Linux Mint originally. This installed via flatpak. I subsequently read about flatpak and saw that it was running the application in a sandbox (from what I gather?) so I don't think it could see any path on my system that was not within that sandbox.

I uninstalled bitcoin core and reinstalled via snapd. That installation was able to obey the parameter as I expected it to so it is now verifying the existing block files and my problem (it seems atm) is solved...


texts: difficulty value vs. computational power

texts:
Assume a miner has a computational power q while the rest of the network has a computational power p = q-1.

Based on Relationship between Hash-Rate and Difficulty: difficulty = hashrate / 7158388.055.

How are p and q related to that?

What I am trying to figure out is, assuming we have a miner that has 50% of computational power, will the difficulty value change so that miner still finds a block in 10 minutes?

If that is the case, won't that difficulty value be too high for the miners that have much smaller computational power?


texts: How to create an new account on a bitcoind server

texts: What is the correct rpc call to start a new account on a bitcoind server?


texts:
This is a question many people ask when they're introduced to Bitcoin.

Bitcoin sounds interesting, but if I want to use this system I will need to get some coins, otherwise, there's no way I can spend them! How can I start?


texts: Lost my old-Electrum 12-word mnemonic seed order

texts: I created my wallet some years ago, and wrote my seed phrase on paper, but unfortunately in a wrong order. Now I suddenly found my note and after some check I find it is in the old-Electrum wordlists. But still I couldn’t find the right order of it. So what can I do?


texts:
I am trying to write a ripple wallet. I want it to be HD wallet.
So I am generating 12 word mnemonics but I am not sure how to give this as a seed to ripple javascript api. See:
https://ripple.com/build/rippleapi/#generateaddress


texts: If two parties submit a conflicting transaction between each other, how does the network decide which one is correct?

texts:
Let's say parties A and B both submit a transaction to the blockchain with a different version of what happened. Party A submits a transaction saying Party B gave him 3 BTC and Party B submits a transaction saying he gave Party A only 1 BTC. How does the network decide which one to put in the next block?

Don't you have to trust a third party? A wallet or some kind of transaction application? How does that work?


texts: Cant start bitcoind - "Block files have previously been pruned"

texts:
I installed bitcoin, following this instructions.

I mostly used it with bitcoin-qt -testnet options, even made a few transactions in testnet. I am using the pruned mode.

Now I want to run the bitcoind and then connect bitcoin-cli to it.

But when I run the following command: bitcoind -testnet, I get the following output:

punnysher@punnysher ~ $ bitcoind -testnet

2018-11-16T09:16:40Z Bitcoin Core version v0.17.0.1 (release build)

2018-11-16T09:16:40Z InitParameterInteraction: parameter interaction: -whitelistforcerelay=1 -> setting -whitelistrelay=1

2018-11-16T09:16:40Z Assuming ancestors of block 0000000000000037a8cd3e06cd5edbfe9dd1dbcc5dacab279376ef7cfc2b4c75 have valid signatures.

2018-11-16T09:16:40Z Setting nMinimumChainWork=00000000000000000000000000000000000000000000007dbe94253893cbd463

2018-11-16T09:16:40Z Using the 'sse4(1way),sse41(4way),avx2(8way)' SHA256 implementation

2018-11-16T09:16:40Z Using RdRand as an additional entropy source

2018-11-16T09:16:40Z Default data directory /home/punnysher/.bitcoin

2018-11-16T09:16:40Z Using data directory /home/punnysher/.bitcoin/testnet3

2018-11-16T09:16:40Z Using config file /home/punnysher/.bitcoin/bitcoin.conf

2018-11-16T09:16:40Z Using at most 125 automatic connections (1024 file descriptors available)

2018-11-16T09:16:40Z Using 16 MiB out of 32/2 requested for signature cache, able to store 524288 elements

2018-11-16T09:16:40Z Using 16 MiB out of 32/2 requested for script execution cache, able to store 524288 elements

2018-11-16T09:16:40Z Using 4 threads for script verification

2018-11-16T09:16:40Z scheduler thread start

2018-11-16T09:16:40Z HTTP: creating work queue of depth 16

2018-11-16T09:16:40Z No rpcpassword set - using random cookie authentication.

2018-11-16T09:16:40Z Generated RPC authentication cookie /home/punnysher/.bitcoin/testnet3/.cookie

2018-11-16T09:16:40Z HTTP: starting 4 worker threads

2018-11-16T09:16:40Z Using wallet directory /home/punnysher/.bitcoin/testnet3/wallets

2018-11-16T09:16:40Z init message: Verifying wallet(s)...

2018-11-16T09:16:40Z Using BerkeleyDB version Berkeley DB 4.8.30: (April  9, 2010)

2018-11-16T09:16:40Z Using wallet wallet.dat

2018-11-16T09:16:40Z BerkeleyEnvironment::Open: LogDir=/home/punnysher/.bitcoin/testnet3/wallets/database ErrorFile=/home/punnysher/.bitcoin/testnet3/wallets/db.log

2018-11-16T09:16:40Z Cache configuration:

2018-11-16T09:16:40Z * Using 2.0MiB for block index database

2018-11-16T09:16:40Z * Using 8.0MiB for chain state database

2018-11-16T09:16:40Z * Using 440.0MiB for in-memory UTXO set (plus up to 286.1MiB of unused mempool space)

2018-11-16T09:16:40Z init message: Loading block index...

2018-11-16T09:16:40Z Opening LevelDB in /home/punnysher/.bitcoin/testnet3/blocks/index

2018-11-16T09:16:40Z Opened LevelDB successfully

2018-11-16T09:16:40Z Using obfuscation key for /home/punnysher/.bitcoin/testnet3/blocks/index: 0000000000000000

2018-11-16T09:16:48Z LoadBlockIndexDB: last block file = 154

2018-11-16T09:16:48Z LoadBlockIndexDB: last block file info: CBlockFileInfo(blocks=2233, size=44632870, heights=1441380...1443684, time=2018-10-31...2018-11-16)

2018-11-16T09:16:48Z Checking all blk files are present...

2018-11-16T09:16:48Z LoadBlockIndexDB(): Block files have previously been pruned

2018-11-16T09:16:48Z : You need to rebuild the database using -reindex to go back to unpruned mode.  This will redownload the entire blockchain.

Please restart with -reindex or -reindex-chainstate to recover.

: You need to rebuild the database using -reindex to go back to unpruned mode.  This will redownload the entire blockchain.

Please restart with -reindex or -reindex-chainstate to recover.

2018-11-16T09:16:48Z Aborted block database rebuild. Exiting.

2018-11-16T09:16:48Z Shutdown: In progress...

2018-11-16T09:16:48Z scheduler thread interrupt

2018-11-16T09:16:48Z Shutdown: done

punnysher@punnysher ~ $


texts: Armory cannot find bitcoin installation in Ubuntu 14.04

texts:
I installed Bitcoin Core version v0.11.2.0-g7e27892 (64-bit)
at /usr/bin/bitcoin-qt.

After that I installed armory 0.93.3-beta-e59e10d38c.

When I launch armory it says "cannot find bitcoin installation".
I go to File > Settings and set "Bitcoin install dir" to /usr/bin.

Yet armory keeps repeating that msg.
Is it a bug?

I’m running Ubuntu 14.04 64bit.


texts: How to tell when bitcoin has really stopped running

texts:
I would like to take bitcoin block data and send it use it to avoid having to go through the blockchain download again on other computers in my local network. To ensure that no db corruption occurs, I stop bitcoin before the transfer. Running the unix command bitcoind stop will return

Bitcoin has stopped running!

I notice that it does still run in top for a few moments after getting this message. This is not a problem right as it's never more than 15 seconds, however I am looking to automate this process using a simple php script.

Using bitcoin-rpc command such as $status = $bitcoin->stop() would yeild a result of "Bitcoin has stopped running" but it may still be running in top.

How do I make sure that bitcoin really stopped running? Or is it safe to preform data transfer as soon as I get this message (does bitcoin keep writing to db after it notifies you it has stopped)?


texts: What is the "Bitcoin Address" for standard multisig transaction?

texts:
Question

A standard multisig transaction is:

scriptPubkey = m <p1> ... <pn> n OP_CHECKMULTISIG
scriptSig = OP_0 <s1> ... <sm>

Where: 1 <= m <= n <= 3.

Note, that it is not P2SH transaction!

So, what is the Bitcoin Address for this transaction?
In case of escrow, what Bitcoin Address should be provided to the trading parties?

Short glossary

p = public key

pH = public key hash, RIPEMD(SHA(public key))

sH = hash of serialized script, RIPEMD(SHA(ser. script))

C = first 4-bytes of SHA256(SHA256(data), where data is

X = bitcoin address prefix (0x00 for P2PKH transaction, 0x05 for P2SH transaction)

0pHC = concatenation of bytes (0: 1-byte, pH: 32-bytes, C: 4-bytes)

Bitcoin Addresses

P2PK transaction

The "Bitcoin Address" for P2PK is Base58(XpC), where "X" (bitcoin address prefix) is not currently defined for P2PK transaction type. See https://en.bitcoin.it/wiki/List_of_address_prefixes.

Where:

X is the bitcoin address prefix (for example, 0x02)
p is the public key
C is the checksum (SHA^2(public key))
XpC is the concatenation of X byte, p string and C 4-bytes

P2PKH transaction

The "Bitcoin Address" for P2PKH transaction is Base58(0pHC).

P2SH transaction

The "Bitcoin Address" for P2SH transaction is Base58(5sHC).

So, again, what may be the Bitcoin Address for standard multisig transaction?

Thanks,
--- Kosta Z.


texts: How do I obtain exponential moving averages using the MtGox API?

texts: To calculate EMAs, do I need to be recording all of the data coming through MtGox's websocket firehose and manually calculating it myself, or are there static calls I can make to the HTTP API to obtain these figures on demand? How can I obtain an EMA for historical data before I begin recording websocket-streamed data?


texts: Why doesn't Multisig provide better security for hot wallets?

texts:
I've recently read somewhere (can't remember the source) that multisig often doesn't provide more security in hot wallets, but increases the size and thus the fee.

I can't seem to comprehend how this can be valid (multisig not providing better security for hot wallets), what could be the reason behind this statement?


texts: Correct syntax for Bitcoin URI: bitcoin://1xxx-etc or bitcoin:1xxx-etc?

texts:
To make clickable Bitcoin links, to let people easily pay from their wallet, I see two formats being used in various situations:

bitcoin:14bTZTm1uX2uVAqHr62oyGFEkwy2mNLbVb?amount=0.25
and
bitcoin://14bTZTm1uX2uVAqHr62oyGFEkwy2mNLbVb?amount=0.25

So that's with and without the two slashes. When testing on Android, they both seem to work. Which is correct?


texts: bitcoin's PoW, real time of creating one block

texts:
i learn that bitcoin is created every 10 minutes and if block is created faster than 10 minutes, Difficulty will increase.

and study deeper, mining process is finding nonce that start 0 to increase 1 until finding hash value same or small rather than  'Target'

now, 2019-02-14, Block #562968 's nonce is 3,534,700,356.

it mean according this answer, it calculate 3GHash to create new block.

according to newest Mining Hardware ASICs, it says ASIC miner is calculating 14~16 TH/s. that does not make sense. PoW hash value is calculated 0.001s with this ASIC.

what i missed?


texts:
I'm new to Bitcoin. I want to use PHP to create a bitcoin wallet on my own website. I came to here https://blockchain.info/api/create_wallet but I don't know how to apply it.

Would like to have good tutorials from some websites or videos.


texts: Which bitcoin wallets let you export to a universal .wallet format?

texts: Which bitcoin wallet applications for android, windows, and mac allow you to export .wallet files that are cross-compatible with each other? Currently there are so many wallet applications out there and I just want to use as few as possible that give a sense of security if one day the app developer just stops developing for their app.


texts: I have started bitcoind on my linux box. How can I ask it what its status is? I assume it is downloading the blockchain and will continue to do so for hours or days. How can I find out where it is in this process?


texts: Does a bitcoinj SPV node forward transactions for itself?

texts:
The bitcoinj library offers a rather convenient WalletAppKit class, which I'd like to accept payments from customers. In order to facilitate the payments I'd offer the customers to send the transaction directly to me, instead of sending it to the Bitcoin Network and eventually reaching me.

If the simple example from WalletAppKit receives a payment that transfers some coins to one of its own wallets, does it announce the transaction to its peers and provides them with the transaction, or does the SPV protocol dictate that the node is a mere consumer of information?

If it does not forward the transactions, what would be the required modifications to allow transaction forwarding?


texts: Is there a way to chain calls in Bitcoin core console?

texts:
Is there a way to chain calls in Bitcoin core client console window like this

validateaddress (getaccountaddress "")

instead of

getaccountaddress ""
validateaddress _address from previous call_


texts: Pros & Cons of Using the "Satoshi" Method to Track User Deposits

texts:
In this question user @lungj suggests using "satoshi" as a marker for user deposits.

Another method I’ve seen used on bitcoin is using satoshis as a
marker. For example, when paying for a one bitcoin item, an additional
7 satoshi could be added to the amount due to distinguish from another
user asked to add 6 satoshi. Payments must be in exact amounts for
this to work (but you can always refund an incorrect payment, less
fees, to a sender). This does not scale all that well if your IDs must
be permanent. This avoids the need for users to interact with a
contract to include metadata.

This method basically allows all users of a service to deposit funds to the same Bitcoin address while allowing us to keep track of who deposited which funds.
Off hand I can think of two potential issues with this method:

If we reserve 1 Bitcoin address to 100 users, we are adding a minuscule amount of $$$ to each payment (between 1 - 10 cents if Bitcoin exchange rate = $100,000)
It only works when we know in advance how much the user intends to deposit (otherwise there's no way of calculating how much extra "satoshi" was added to a payment (so it won't work for general deposits)

What are some of the other pros and cons of using this protocol to keep track of user deposits? Are the issues above solvable?
Thanks


texts: I know it's pointless. I just want to learn how to do it. Are there any guides out there?


texts: How do i retreive my bitcoins that I purchased but never receaved because of the dodgie bitcoin qt years ago?

texts: Hi guys I am seeking to retrieve my bitcoins I purchased years ago but my bitcoin qt never synced to receive them! I have now downloaded bitcoin core and I was advised that once I have done that it should automatically just transfer over but it hasn't! So what are my options to get hold of my bitcoins I purchased years ago????


texts: How to sign messages deterministically with bitcore?

texts: How do you sign messages deterministically with bitcore?


texts: How to calculate signature generation, signature verification, transaction verification speed?

texts:
I read this post on Bitcoin Scalability.
As far as I understand sequence of steps in Bitcoin, simplified version of performing transaction should be following:

On Sender's side:

Create transaction
Generate signature and sign
Broadcast the transaction to peers

On Peer's side:

Get the transaction
Verify signature
Verify transaction
Pass to the next peer. - ???

//if a peer is a miner

Collect transactions into block
Calculate PoW for the block
If found include it to his version of the blockchain
Broadcast the block (with nonce and targe)

Other peers:

Get the block
Verify that PoW for block is Valid
Include the block into their version of the blockchain

I would like to understand Bitcoin's performance speed at every step in general or given my specifications of the laptop if possible.
How I can calculate signature generation, signature verification, transaction verification, block PoW verification, **etc speed?**


texts: computational effort needed to mine a block given the number of leading zeros in the resulting hash?

texts: What is the computational effort to mine a block successfully given the number of leading zeros in a resulting hash?


texts: ecdsa - Create Private key and Bitcoin Address

texts:
I have the following code:

import binascii
import hashlib
from fastecdsa import keys, curve

# generate a private key for curve P256
priv_key = keys.gen_private_key(curve.secp256k1)
print (priv_key)
print ("______")

# get the public key corresponding to the private key we just generated
pub_key = keys.get_public_key(priv_key, curve.secp256k1)
print (pub_key)

Which returns this:

68553277193328358088381091283586955911631072878513122367770244549235879948867
______
(defdba7ac050b698bc63134bbc495064b5a99125b023d8ae92d21ca43be77961,
 68ed2abc9d36bae64947b94dd15864e3b2f7601b7009c5b9bae8a8775553fea0)

The first one is the private key, and the second one is the public key. How can I convert these numbers to Bitcoin format?

I've tried with this script: https://github.com/bitcoinbook/bitcoinbook/blob/second_edition/code/ec-math.py

But doesn't work in Python 3.5


texts: Single address wallets - no change addresses

texts:
Is it legal for Bitcoin transaction to spend output back to one of the input addresses? Namely, to create a single address wallet (paper wallet), so that change addresses do not need to be generated.

Looks like all popular wallets create change addresses for privacy reasons, but I'd like to know if this is also a limitation of protocol. Also asking this question separately from deterministic address generation.


texts: How do I get coin supply on Bitcoin core?

texts:
I've seen in other QT wallets I can get how many coins are in circulation typing a command like  getsupply, they also have this information in the output of the command getblock <hash>.
Is there a way to get this information using a RPC Command on Bitcoin Core?


texts: Is there some good example on how to process a basic tx's scriptsig and get the recipient's address from the raw transaction?


texts:
I have sent BTC to cryptopay wallet. It is still showing pending. It has been 8 hours up to now. Can you please tell me what could be the error or the problem and how I can solve the issue
Thank you


texts: Given the recent events and today's news about MtGox filing for bankruptcy, is my money on MtGox completely lost? and what are my options now?


texts: Is this "transaction malleability" really an issue?

texts:
The well-known Bitcoin exchange Mt.Gox last week suspended all Bitcoin withdrawals because of "technical issues", which today have been better described in this press release.

This looks like a serious problem, but is it actually true?
Has this issue been confirmed by third parties?
Has it really been known "for a while"?
What true impact can it have?


texts:
How can I buy or download the data of Kraken bitcoin trades 2015-2016 in cvs format. I need it for my trading strategy (time stamp, volumes, bid, ask)
can someone help me or make for me?


texts: How to get all income transactions of an address?

texts:
I want to get list of all address's income transactions since the genesis block

import requests, json

rpcPort = 8332
rpcUser = '[removed]'
rpcPassword = '[removed]'

#Accessing the RPC local server
serverURL = 'http://' + rpcUser + ':' + rpcPassword + '@localhost:' + str(rpcPort)

headers = {'content-type': 'application/json'}
payload = json.dumps({"method": 'listunspent', "params": [0, 999999, ['1KuWLoZuoJgz3N6sLoAwGth9XGm8YuFTGt']], "jsonrpc": "2.0"})
response = requests.post(serverURL, headers=headers, data=payload)
print(response.text)

it returns

{"result":[],"error":null,"id":null}

But according to https://blockchain.info/address/1KuWLoZuoJgz3N6sLoAwGth9XGm8YuFTGt there are a lot of transactions. How to get list of address-related transactions without private key? Can I add address not owned by me to local account to achieve transactions by getreceivedbyaddress command?


texts: Calculate Segwit address from public address

texts:
I would like to calculate the segwit address of a public address.

First step:
take the compressed public address:
1L88S26C5oyjL1gkXsBeYwHHjvGvCcidr9

do a sha256 on that address:
151de228f6bec7635097f7813786830505d04bf56806f11eb056441fdc917d41

do a ripemd160:
9bbfb2424372d687cf35fd7d1e978f85a11157ca

encode with Base58:
usT1ggHqtEAcGd4ZysWqtxaaQmT

There is something wrong since every segwit address should start with "3". Can someone help me which step it is?

My source of how a segwit address is calculated is: How to get legacy address and private key from Segwit P2SH address? Quote:

  You have the private key so you can just derive the address from there. Get the corresponding public key, hash it with SHA256 and then that result with RIPEMD160. Then perform Base58Check Encoding on it.


texts: Create a Double sha256 block and trandaction

texts:
I have same problem whit create a double sha256 of the transactions and blocks with C++.

The hash block it is created with the concatenation of these data,

version + previusBlock + merkleRoot + timeStamp + bit + nonce

In the hash block is not necessary to include the all data raw transaction because is are include in the merkleRoot, right?

For create, hash transaction is create whit the concatenation of these data,
versionRawTransaction + output of the transaction input + scriptSing + sequences transaction input + cAmmount transaction output + publicKeyScript + lockTime raw transaction

Or are include the data for saving the variable structure? in this method

numberRawTransactions + versionRawTransaction + numbarTransactionInput + output of the transaction input + scriptLenght + scriptSing + sequences transaction input + numbarTransactionOutput + cAmmount transaction output + publicKeyScriptLenght + publicKeyScript + lockTime raw transaction

Now I've tried to apply this theory in my C ++ program but can't get the desired hash. Can you help me?

This is the my test code

    TEST(hash_test, first_test_double_sha_bit_genesi_block_bitcoin_crypolibrary)
{
    //Init logger
    FLAGS_minloglevel = 0;
    FLAGS_logtostderr = true;
    google::SetLogDestination(google::GLOG_WARNING,  "/home/vincenzo/Github/SpyCblock/test/log/first_test_sha_not_on_bitcoin_protocolo.log");

    string version = "01000000";
    string previusBlock = "0000000000000000000000000000000000000000000000000000000000000000";
    string merkleRoot = "3ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a51323a9fb8aa4b1e5e4a";
    string timeStamp = "29ab5f49";
    string bit = "ffff001d";
    string nonce = "1dac2b7c";

    stringstream stream;

    stream  << version << previusBlock << merkleRoot << timeStamp << bit << nonce;

    Bytes byte = asciiBytes(stream.str().c_str());
    Sha256Hash shaHash = Sha256::getDoubleHash(byte.data(), byte.size());

    LOG(INFO) << "The hash genesi block converting with double sha256: " << shaHash.ToString();
    ASSERT_EQ(shaHash.ToString(), "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f");

}

but I get this result 46f4d3f53251d05ab58a3f8925ce7023f2115dc38468ec78521c7d0e1dc7bd19

Since I know practically nothing in cryptography in practice, I relied on this library where I use this type of data here that makes the double sha256 Find here

Sorry for my terrible English but I'm learning


texts:
I'm new to Bitcoin and I have recently purchased a few fractions of Bitcoin. My BTC are stored on what I understand is an online wallet (a website where I log in using two-factor authentication and where I can buy/sell BTC as well as send/receive BTC). The problem is that my BTC are stored online, which means that they could be potentially exposed to threats like hackers, viruses, technical problems, the website going down, fraud, etc. So, after having searched for other options, I decided that the most secure way of storing BTC would be on a paper wallet.

Creating a paper wallet at bitaddress.org doesn't seem to be that difficult, but of course one has to be sure that the public and private keys are being generated in a completely safe, malware-free environment. Many advanced users employ what are to me very complicated techniques for generating such keys, such as booting the operating system from a pendrive, using Ubuntu, Tails and many other programs and procedures I'm not at all familiar with. Other users just make sure the computer is clean, go to bitaddress.org and then turn off the internet connection before generating the keys. Others save bitaddress.org as an html file and then open that file offline to generate the keys, while others download a copy of bitaddress.org from github and open that copy offline to generate the keys.

Even after having read about BTC, the BTC world is still very complicated to me, so here come the questions:

1) What if I restore my wifi router to factory settings and set it up with a new wifi password and then buy a new computer, access the internet through wifi just for a few seconds just to go to bitaddress.org (and no other web) and then go offline to generate the keys? Would this be a completely safe environment to generate the keys? I can't think of anything cleaner than a recently bought computer. How could I make sure no sensitive information about the keys gets stored anywhere on the computer or web browser after having generated them? This is important because I'm planning to then use my computer for daily work, so I will generate many different wallets at once and then probably never use the same computer again to generate more wallets.

I have read somewhere that one can download a copy of bitaddress.org to a pendrive and then open that website on a computer that "has never touched the internet", but I think that opening bitaddress.org online for a few seconds on a recently bought computer should be a more secure way.

Also, would it be a good idea to connect my computer to the internet by using my cell phone as a router, that is to to say, by using the cell phone's cellular data connection instead of wifi? I think a cell phone's connection to the cellular network should be more difficult to hack than a wifi connection, but anyway cell phones may also have viruses, so I'm not 100% sure what I should do.

2) Why is it that some people prefer not to choose the first generated pair of keys (at bitaddress.org) but instead generate further pairs to choose from?

3) bitaddress.org generates a public key and a private key. Is this public key the same as the BTC address?

4) What are the differences between the different types of wallets offered at bitaddress.org?

5) How can I make sure I'm accessing a legitimate version of bitaddress.org. In other words, how can I make sure no hacker has modified something at bitaddress.org in order to be able to capture generated keys? (I have read somewhere something about computing the "hash" or something like that.)

6) Is there a limit to the number of BTC I can send to/store in a particular address? Can one send any fraction of BTC to a particular address?

Thanks in advance!!