Latest posts of: darius2020

New hash stays for what ?

http://www.businessinsider.com/mtgox-statement-on-withdrawals-2014-2

"
We believe this can be addressed by using a different hash for transaction tracking purposes. While the network will continue to use the current hash for the purpose of inclusion in each block's Merkle Tree, the new hash's purpose will be to track a given transaction and can be computed and indexed by hashing the exact signed string via SHA256 (in the same way transactions are currently hashed).

Read more: http://www.businessinsider.com/mtgox-statement-on-withdrawals-2014-2#ixzz2svwR4ZkL

"

Quote

Everybody could make as much transactions as they like with as small amounts as they like.

Exactly the idea staying behind Bitcoin -
No limits on electronic payment transactions.

Quote

People can keep sending their bitcoin back and forth with no cost, and the whole network will be clogged.
Those "real" transactions can hardly be included in a block then...

Smart people don't have any need to send their bitcoin back and forth.

To your surprise, most real banks offers no-fee money transfers within the same bank,
so large banks make this offer available to multi-Ms of clients for free,
exactly as mobile telephony networks offer free calls within the network,
not making people to sit 24h/365 to talk and talk forever.

Nothing new under the Sun.

If your intention is to find the way to limit number of Bitcoin transactions,
so doubling the transaction fee every year you can easily freeze Bitcoin network.

Smart real bank systems can handle Bs of transactions
so please don't suggest Bitcoin network has no prospects to grow.

you said:

Quote

Transaction fees serve 2 purposes in the Bitcoin network. It rewards the miners for confirming transactions and also sets a priority on the inclusion of your transaction in the next block. ie, if you pay a higher transaction fee, chances are greater you will be included in the next block so that it can be verified and confirmed. For faster confirmations, spend more on the transaction fee.

Miners or (minters = money minting) are rewarded by default ( 25 BTC today)
so there is no need to set any priority on the inclusion of one's transaction into the next block.

Acting otherwise, miners or "minters" can demand higher and higher transaction fees to be offered
to have transaction hashed within a block, making Bitcoin payments to collapse
transaction fees to double and double on every strike by miners ( minters)
forcing those accepting Bitcoin payments to establish Bitcoin block hashing agency to
keep business sound.

Quote

chances are greater you will be included in the next block so that it can be verified and confirmed. For faster confirmations, spend more on the transaction fee.

How much in transaction fee makes you to include a specific transaction into the new block ?

And "faster confirmation" stays for what ?

5 min, 1 hour, 1 day , 1 month ?

It looks like
Bitcoin can collapse on transaction fee doubled from time to time
Bitcoin can collapse on no-fee transaction to be delayed or even never included into the new hashed block

So Bitcoin network turns into Easy Entry - Hard Exit Game

You can accept Bitcoin payments buy to have pay a large transaction fee to exit Bitcoin game.

First Class traditional banks offer clients no-fee transaction today
so the only business in accepting Bitcoin is deflanatory feature built-it into generation of Bitcoins.

If you can delay Bitcoin payment transaction so you can easily violate the trust in 1 BTC at $900
transactions, since why should we risk buying Bitcoins, accepting Bitcoins as payments
if you can stop us with spending Bitcoins, doubling transaction fee from time to time,
making small Bitcoin payments expensive, since transaction fee can make 50% or more of the sum transferred.

So my advise to miners ( minters) is to keep transaction fee as low-as-possible,
accept no-fee transactions, don't delay zero-fee transactions
and play fair, since otherwise interest in Bitcoin can easily dimnish.

Hi,

Can you help with Bitcoin block hashing algorithm in Javascript ?

I run block hashing application in plain Javascript
and there is a bug in the algorithm published
on
https://en.bitcoin.it/wiki/Block_hashing_algorithm

since I don't get the correct digest2 (there is no leading 0s)

Hi,

I need to download headers from all blocks.
Blockchain.info comes with API
to getJSON to get a single block header

are you aware how to make API call to download all block headers at once
or as a file ?

example, demo

Contacted blockchain.info , no reply.

If you know any other source for block headers, please let me know.

Hi,

how to contact developer of Bitcoin Javascript Miner Master (no contact details provided) ?

Application is alpha demo, not working yet.

Interested to modify it to read block headers from Blockchain.info via API
reading 6 input parameters via getJSON

to verify signed Blocks from the past.

Any help ?

Hi,

I am trying to download Bitcoin block headers from Blockchain.info via API
using
https://blockchain.info/block-index/100?format=json

and getJSON + Javascript
to parse json file from a remote web server
to get 6 block header input parameters into my Bitcoin miner in plain Javascript (under development)

Tell me how to modify this code to get remote json file and parse data

(just tested this demo on a web server)

Quote

<html>
<head>
<title>the title</title>
   <script type="text/javascript"
   src="/jquery/jquery-1.3.2.min.js"></script>
   <script type="text/javascript" language="javascript">
   $(document).ready(function() {
   $("#driver").click(function(event){
   $.getJSON('https://blockchain.info/block-index/100?format=json', function(jd) {
   $('#stage').html('<p> Hash: ' + jd.hash + '</p>');
   $('#stage').append('<p>Ver: ' + jd.ver+ '</p>');
   $('#stage').append('<p>Time: ' + jd.time+ '</p>');
   });
   });
   });
   </script>
</head>
<body>
   <p>Click on the button to load result.html file:</p>
   <div id="stage" style="background-color:blue;">
   STAGE
   </div>
   <input type="button" id="driver" value="Load Data" />
</body>
</html>

Do I have to loop API call
https://blockchain.info/api/blockchain_api

http://blockchain.info/rawblock/$block_index

to parse blocks i=1 to 10

http://blockchain.info/rawblock/i

or API can be modified to download file made of 10 block headers in JSON format in one pass ?

Just testing one another getJSON test to access Blockchain header via API

Quote

<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
$("button").click(function(){
$.getJSON("https://blockchain.info/block-index/100?format=json",function(result){
$.each(result, function(i, field){
$("div").append(field + " ");
});
});
});
});
</script>
</head>
<body>

<button>Get JSON data</button>
<div></div>

</body>
</html>

Ok, this Javascript code is run on local web server, accessing file from a remote web server
but exactly the case with Blockchain.info + API

Blockchain.info = remote server
My Javascript getJSON is run locally

previewed a large number of examples, demos and none worked for me.

Any help ?

Hi,

Tell me how to download Bitcoin block headers (6 input parameters) parsed as csv data file ?

I run Javascript Bitcoin block hashing demo application and plan to run it for every block hashed in the past
to verify nonce.

Any idea ?

What I need are 6 Bitcoin block header raw input parameters
as defined by
https://en.bitcoin.it/wiki/Block_hashing_algorithm

Quote

Field    Purpose    Updated when...    Size (Bytes)
Version    Block version number    You upgrade the software and it specifies a new version    4
hashPrevBlock    256-bit hash of the previous block header    A new block comes in    32
hashMerkleRoot    256-bit hash based on all of the transactions in the block    A transaction is accepted    32
Time    Current timestamp as seconds since 1970-01-01T00:00 UTC    Every few seconds    4
Bits    Current target in compact format    The difficulty is adjusted    4
Nonce    32-bit number (starts at 0)    A hash is tried (increments)    4

so data only parsed.

Tried Blockexplorer
http://blockexplorer.com/block/00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d

Unfortunately block header 6 parameters are not parsed, too much ASCII text.

any help ?

Thanks

you said:

Quote

SwapOrder operates on a set of bytes - just reverses their order.
LittleEndian takes a 32-bit integer and outputs 4 bytes in little-endian order.

In case of Bitcoin block header SwapOrder operates on a string of hex numbers, reversing their order
2 bytes-wise ( hex pairs)

example below

Quote

$rootHash = SwapOrder('2b12fcf1b09288fcaff797d71e950e71ae42b91e8bdb2304758dfcffc2b620e3');

The problem is with decimal number converted to little Endian
since
decimal value is converted to Hexadecimal value
1222 4C6
Epoch Unix time (decimal)
1305998791 4DD7F5C7 (even number of hex symbols

Now I need to convert hexadecimal value to a string of hex digits ( 0,1,2.... A,C...F) - hex (base 16) representation
and append "0" to "4C6" to get even number of hex digits and operate SwapOrder 2 bytes - wise

$time = littleEndian(1305998791);

from
https://en.bitcoin.it/wiki/Block_hashing_algorithm

Quote

The header is built from the six fields described above, concatenated together as little-endian values in hex notation:

(1305998791)10 = (4DD7F5C7)16

So in theory and practice, I am safe converting today Unix epoch time (decimal number) to hexadecimal value with even number of hex digits - hex (base 16) representation

Hex2String conversion is not the right tool, converting
4DD7F5C7
to
M×õÇ (ASCII string)

so the following code looks to work fine converting Unix epoch time value = 1305998791 to hex (base 16) string followed by SwapOrder(num.toString(16))

Quote

<!DOCTYPE html>
<html>
<body>

<p id="demo">Click the button to display the formatted number.</p>

<button onclick="myFunction()">Try it</button>

<script>
function myFunction()
{
var num = 1305998791;
var x = document.getElementById("demo");
x.innerHTML=num.toString(16);
}
</script>

</body>
</html>

if I am wrong, please correct me

Thank you.

Quote

SwapOrder is just converting big to little endian and you don't use it in the python code, because you already specify it as converted to little endian.

The issue is PHP code from example comes either with SwapOrder and LittleEndian

Quote

$rootHash = SwapOrder('2b12fcf1b09288fcaff797d71e950e71ae42b91e8bdb2304758dfcffc2b620e3');
$time = littleEndian(1305998791);

I have implemented SwapOrder (BytesSwap) in Javascript
Hex string 2 bits string
but I am not sure what makes the difference between SwapOrder and LittleEndian

since input data (6 parameters) for each example in Python, PHP is parsed from block header the other way
I don't need any parsing in example in plain C

http://pastebin.com/bW3fQA2a

Quote

Try google: https://www.google.com/search?q=sha256+javascript

You are exactly right, there is a number of sha256 implementations in Javascript
but what I was looking for was Bitcoin block header hash implementation in Javascript ( still missing)

I need the way (API, database, datafile (csv) as 6 input parameters to run Block header hash off-line
to verify every block (nonce) from the past.

How to download and parse Bitcoin block header 6 input parameters and save to file as csv , any source, web link to such file ?

Ok, Javascript is slow but is nice for education or presentation on how Bitcoin block header hash works
step-by-step.

I tried to download Bitcoin block header 6 input parameters from Blockchain.info
unfortunately format is not smart ( a lot of parsing required)
and time is not in Unix epoch format

btw
I don't see block header parsing (string made of 6 input parameters + BytesSwap, LittleEndian in plain C example from
http://pastebin.com/bW3fQA2a

I am really grateful for your help.

Looking for working Bitcoin block header hashing algorithm in Javascript

and exaplanation about LittleEndian and ByteSwap implementation in PHP

Quote

$version = littleEndian(1);
$prevBlockHash = SwapOrder('00000000000008a3a41b85b8b29ad444def299fee21793cd8b9e567eab02cd81');
$rootHash = SwapOrder('2b12fcf1b09288fcaff797d71e950e71ae42b91e8bdb2304758dfcffc2b620e3');
$time = littleEndian(1305998791);
$bits =littleEndian( 440711666);
$nonce = littleEndian(2504433986);

vs. no LittleEndian implementation in Python

Quote

>>> header_hex = ("01000000" +
"81cd02ab7e569e8bcd9317e2fe99f2de44d49ab2b8851ba4a308000000000000" +
"e320b6c2fffc8d750423db8b1eb942ae710e951ed797f7affc8892b0f1fc122b" +
"c7f5d74d" +
"f2b9441a" +
"42a14695")
>>> header_bin = header_hex.decode('hex')

from
http://shiplu.mokadd.im/95/convert-little-endian-to-big-endian-in-php-or-vice-versa/

Quote

In PHP you might have to convert the endianness of a number. PHP does not provide any function for this even though it has function for almost everything.

Hi,

I am looking for expert in Bitcoin block header hashing algorithms in PHP, C, Python, Javascript
to discuss Bitcoin hashing algorithms from bitcoin.it in PHP, Python, plain C,
developing Javascript
as below

https://en.bitcoin.it/wiki/Block_hashing_algorithm

Hi,

Looking for Javascript based block hashing algorithm to verify signed blocks and verify calculated nonce
for off-line presentation to students.

Could you help me ?

https://en.bitcoin.it/wiki/Block_hashing_algorithm

code in Python, plain C, PHP (see above)

implemented sha256 in Javascript, implemented Little Endian,
No support for hex2bin in JS, so
I use hex2decimal + decimal2binary
but what is generated is a number so number of bits is not correct < 640 bits

I need 80 bytes long header ( 640 bits number or string) as input into sha256

any idea or reference to plain Javascript implementation of Bitcoin clock hashing ?

What is s source for parsed block headers ( 6 input parameters) + Time in Unix Epoch format ?
I would prefer datafile storing 1-100 headers or another just another solution
to let me Javascript hashing to read input parameters and verify calculated nonce.

Any idea ?

Thanks

Quote

Sorry, I misunderstood. I thought you were trying to parse block headers from "the blockchain", not web pages from blockchain.info.

I need to parse block headers of the signed blocks to test my hashing algorithm.

Already implemented SwapOrder (BytesSwap) or Little Endian.

Implemented hex2decimal + decimal2binary

the issue is I get binary as a number, so number of bits is not correct.

Any idea for hex2bit in Javascript since
examples from the Internet failed to work (Firefox)

Should I add trailing 0s to hex2bin ?

done in Python

Quote

header_bin = header_hex.decode('hex')

from
https://en.bitcoin.it/wiki/Block_hashing_algorithm

btw

Javascript is not parsing

Time stamp from
http://blockchain.info/en/block-index/458660/00000000000000000fcea0d175785506f4681dc94d1fcf50deeda8082caf1543]http://blockchain.info/en/block-index/458660/00000000000000000fcea0d175785506f4681dc94d1fcf50deeda8082caf1543 [/url]

correctly

Quote

Date.parse("2014-01-15 15:33:34");

results in

Quote

NaN

ok

just tested
Date.parse("1970-01-01T00:00:00");

works fine

result

Quote

1332284400000

so I need to inject "T" character after first 10 characters in time stamp
from
http://blockchain.info

If you know other solution just let me know.

Quote from: DannyHamilton on January 15, 2014, 04:36:26 PM

The time in the block header is already stored in Unix Epoch Time.

Perhaps this reference will be helpfull:

http://james.lab6.com/2012/01/12/bitcoin-285-bytes-that-changed-the-world/

Time stamp in Blockchain from
http://blockchain.info/en/block-index/458660/00000000000000000fcea0d175785506f4681dc94d1fcf50deeda8082caf1543
is not in Unix Epoch Time.

Format is

Quote

Timestamp 2014-01-15 15:33:34
I need it converted into Unix epoch time

What is a source of block headers coming with Time Stamp in Unix time ?
Can you give www address ?

What I need more are the following functions implemented in Javascript

hex2bin
SwapOrder (for hex)
or LittleEndian

either in Javascript

got Hex2Bin function implementations in Javascript from
http://stackoverflow.com/questions/7695450/how-to-program-hex2bin-in-javascript

any better solutions suggested ?

none for hex swaporder Javascript yet

and finally I need to implement

Hex2Bin > Hash > Hex2Bin > Hash

to get Bitcoin Block header hashed

Still looking for Bitcoin Block Header hash implementation in Javascript ( no Java code)
to be run off-line.

Hi,

How to convert time from Block header to Unix time ?

Time stamp in block header ( past hashed blocks) is in the following format

http://blockchain.info/en/block-index/458660/00000000000000000fcea0d175785506f4681dc94d1fcf50deeda8082caf1543

Timestamp 2014-01-15 15:33:34
I need it converted into Unix epoch time

as declared by
Block hashing algorithm
Time Current timestamp as seconds since 1970-01-01T00:00 UTC Every few seconds 4

in PHP
$time = littleEndian(1305998791);

Quote

header_hex = ("01000000" +
"81cd02ab7e569e8bcd9317e2fe99f2de44d49ab2b8851ba4a308000000000000" +
"e320b6c2fffc8d750423db8b1eb942ae710e951ed797f7affc8892b0f1fc122b" +
"c7f5d74d" +
"f2b9441a" +
"42a14695")

fourth parameter in Python code

file:///E:/Block%20hashing%20algorithm%20-%20Bitcoin.htm

or in plain C
http://pastebin.com/bW3fQA2a

Quote

// we are going to supply the block header with the values from the generation block 0
header.version = 1;
hex2bin(header.prev_block, "0000000000000000000000000000000000000000000000000000000000000000");
hex2bin(header.merkle_root, "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b");
header.timestamp = 1231006505;
header.bits = 486604799;
header.nonce = 2083236893;

I plan to read input parameters ( block headers ) from blocks hashed in the past to verify nonce
as a presentation to students.

Can you help me ?

I am testing Block hashing algorithm from

https://en.bitcoin.it/wiki/Block_hashing_algorithm

code in Python and PHP + sha256 library

+ code in plain C from
http://pastebin.com/bW3fQA2a

unfortunately block header parameters from
http://blockexplorer.com/block/00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d

don't come in sha256 hashing format

since I need Unix time conversion for >>> Time?: 2011-05-21 17:26:31

http://blockchain.info/en/block-index/458660/00000000000000000fcea0d175785506f4681dc94d1fcf50deeda8082caf1543

the same problem with time parameter.
Any idea how to download block headers file
as 6 parameter input into my block hashing algorithm in Javascript ?

Hi,

Block hashing in Javascript - Could you help me with implementation ?

I am looking for block hashing in Javascript demo, reading input parameters from Blockchain ( 6 parameters)
saved to database and run off-line, as demo for students to verify the calculated nonces were correct from the first block.

Looking for hashing algorithm ( sha256 in Javascript already works fine)
and 6 input parameters as datafile.

Any idea ?

It looks like
Bitcoin idea by Satoshi has no future
since transactions can be easily disrupted by miners on strike, requesting more and more money
in transaction fees.

Let me know what is a chance to have Google to join Bitcoin as No.1 Miner
to process every dust, micro, nano Bitcoin transactions as intended by Satoshi.

Real bank money transfer, payment transactions are almost free
so if you are not a miner, there is no sense to buy Bitcoin, risk Bitcoin processing, storing, transaction
verification to buy goods since withy real money transactions are processed on-line at zero-award, fee-free if you have account with one of key banks.

Scott Li is exactly testing microtransactions in Bitcoin ( micro nano transactions) for us .
Name of his service is #TipperCoin on Twitter.

If Scott fails to succeed so the only chance for Bitcoin to survive is price of Bitcoin to rise on speculation by investment funds.

Overnight risk for traders to accept payments in Bitcoin is too high.

Two of my friends founded private banks 20 years ago
and any risk in banking system must be contained.

Since risk in price fluctuactions of Bitcoin v. Dollar cannot be contained
the only risk free business transacted is the business by Bitcoin miners, minting 25 Bitcoins
for sale.

Market is flooded with thousands of Th/s miners today
so it's now a time for major players like Google, IBM to join
Bitcoin mining markets with Ph/s miners,
reducing number of individual miners to Zero.

Miners are insiders within Bitcoin network.
Non-Miners are outsiders within Bitcoin network.

Outsiders are controlled by insiders (a small group of miners setting their own rules to make as much Bitcoins as possible).

So the only way for Bitcoin Network to survive is to accept zero-fee, no-award transactions (microBitcoin, nanoBitcoin, BitcoinTips since otherwise Bitcoin democracy is controlled by supremacy of few miners at no risk of Bitcoin vs. Dollar fluctuactions in exchange rate.