Topic: ★☆ Get Help Here | The Ultimate Help Thread! | Free Giveaways ★☆ - page 4. (Read 7872 times)

Recently, during this year, we have seen a game, Watch dog being infiltrated by botnets, used for mining.

Then there was Ads on Yahoo, doing the same thing.

What, apart from AV programs, and 3rd party firewalls, can detect and stop these botnets? Monitoring tools etc.

Gah, I'll give that guy the 1 GHS if he promises to take his spamming down a level.
Acidyo, please PM me to claim this gift.  I'll send the CEX.io voucher code then.

Post your questions here (:

I'll be offering the same promotion for the next 50 questions.
I'll be giving away another WoodWallet.

We're not closing up shop anytime soon


Sounds good. Danny if you want to shoot me a public address and shipping addy when you get a chance it'd be appreciated.

Well I feel embarrassed now
Converting those hashes to decimal doesn't work for me
So I can't do the maths for my own bet.
On the upside, I know why checking the genisis block didn't work for me.
One of the reasons anyway.

Thanks for the thread devthedev,
Give the woodwallet to DannyHamilton.

Hey fantastic, I never win anything.
And I didn't really win this.
Tell you what DannyHamilton,
I'll flip you for it.
Next block/118:
I bet remainder is over 58.

It means extremely small amounts of bitcoins, such as 10 satoshis, etc.

Before you close shop - What is the "dust" everyone is talking about?

And congratulations on the winners. 

Just shot Monbux a PM. When he comes online he'll reply via the thread to arrange transfer of the GH/s. Congrats Acidyo!

Block: 305605
Hash: 00000000000000002e2b25627d27cbe11e664406f4d05cf2f00b8171d190110f
In decimal: 1132049287128551868613215852162935821461544770171095224591
Remainder when dividing by 109: 71

Someone check my work, but I think the winner is:
https://bitcointalksearch.org/topic/m.7256769

If so, then it appears that "Acidyo" is the winner.

Thanks for all your help up to this point DannyHamilton. JohnFromWIT, PM me your public address and your physical address and I'll get a Wood Wallet out to you. Congrats!

Block: 305604
Hash: 0000000000000000299e9634677e11a49a454173b11d5e06e7a79f7a546779e3
In decimal: 16328106664413917946375602345914260453145169397703949917744
Remainder when dividing by 109: 37

Someone check my work, but I think the winner is:
https://bitcointalksearch.org/topic/m.7238969

If so, then it appears that I'm the winner.  I appreciate it, but I have no need for the prize.  If possible, I'd like to donate my prize to the person I responded to in that post "JohnFromWIT".  If JohnFromWIT does not want it, then I'll accept it and give it to someone local as a gift.

That seems like the best way to do it. We'll use block 305604 and 305605 then. If I get drawn either time we'll use the next blocks.

You could make it provably fair by dividing the block hash of the next solved block (block 305601, or some later block if you don't see this message soon enough) by 109 and using the remainder as the "chosen random number".

This way everyone knows that you didn't just pick a favorite, since they can all repeat the calculation and see that the result is correct.

I assume you aren't giving the prizes to yourself?

If so, then you could wait for another block if the result is a post of your own.

If you decide to do this, it would be best to announce that is what you are going to do (and which block will start the process) ahead of time, so it doesn't look like you just waited for a block you liked.

I'd say that's about 50 questions asked. I'll be drawing two numbers, the first for the Wood Wallet and the second for the CEX.io voucher. I'll post the results in 20 minutes.
Your entry numbers are based on the post number that you can see to the top right of each post.

You use computer software to do it, because the math involved is tedious and time consuming. A computer can do such repetitive tasks quite quickly, but you wouldn't want to do it by hand with paper and pencil.

Specifically:

Start with identifying the curve being used and the base point of prime order on the curve.

In the case of Bitcoin, the curve is the Secp256k1 curve.
This is the curve described by the function:
y² = x³ + ax + b

Where:
a=0 and b=7

In the case of Bitcoin, the base point is the point on the curve with the (x,y) coordinates of:
(881060208356437498713259502322696549220009655260441506808002997766225867667840, 32670510020758816978083085130507043184471273380659243275938904335757337482424)

Next, perform elliptic curve point multiplication multiplying the base point by the private key scalar.

Elliptic curve multiplication in this case is the process of repeatedly adding the base point, so if your private key is 3, then your public key would be determined by adding the base point 3 times.  The process of point addition is defined as taking two points along the curve and computing where a line through them intersects the curve. The negative of the intersection point is used as the result of the addition

Obviously if you are adding a point to itself, then you only have 1 point on the line for the first calculation.  The process of adding a point to itself (point doubling) is defined as taking the tangent of the point on the curve and computing where the tangent line intersects the curve.

Since private keys are extremely large numbers, it would take a prohibitively long time to just add the base point repeatedly to the result of each calculation that many times.  Instead elliptic curve point multiplication has a shortcut.  You can repeatedly double, to get through many iterations very quickly, and then add to these larger results as needed to reach the appropriate number of iterations.  For example, if the private key was 100, you could do the find the public key in 8 operations (rather than 100 individual additions):

If the base point is G and the private key is 100...

double G to get 2 X G
add G to get 3 X G
double 3 X G to get 6 X G
double 6 X G to get 12 X G
double 12 X G to get 24 X G
add G to get 25 X G
double 25 X G to get 50 X G
double 50 X G to get 100 X G

The process for figuring out when to double and when to add can be described with the following process:

Start with the private key as the "number of remaining additions".

• If the number of remaining additions is even, then write down a "D" (to represent "Double").  If the number of remaining additions is odd, then write down "A" (to represent "Add")
• If the point was odd, (and you therefore wrote an "A") then subtract 1 from the number of remaining additions
• If the point was even, (and you therefore wrote a "D") then divide the number of remaining additions in half
• Repeat this process until the number of remaining additions is 1

Now, you can step through the list you wrote down in reverse, doubling or adding as indicated.  We can see this with our example of 100:

100 is even (D)
50 is even (D)
25 is odd (A)
24 is even (D)
12 is even (D)
6 is even (D)
3 is odd (A)
2 is even (D)

In reverse we get the instructions we saw earlier: Double, Add, Double, Double, Double, Add, Double, Double.

When you complete your elliptic curve point multiplication, the resulting point is your public key.

Next you need to calculate the SHA-256 hash of your public key.  I'm sorry, but I'm not going to try and walk you through that mathematics.  You can read about it here:
http://en.wikipedia.org/wiki/SHA-256

The result will be a 256 bit number.

Next you take a RIPEMD-160 hash of the result of the SHA-256 hash. I'm sorry, but I'm not going to try and walk you through that mathematics.  You can read about it here:
http://en.wikipedia.org/wiki/RIPEMD-160

The result will be a 160 bit number.

The result of this hash is what is actually used in the transactions and blockchain to represent where the bitcoins are "sent to".  Bitcoin addresses are we know them are not stored in the blockchain at all.  They are this 160 bit number with a checksum (to help wallets catch a typo so you don't accidentally send to the wrong RIPEMD-160 hash), and a version number and then converted from a 160 bit binary number to a form of base58 (so you only need to type, write, print, or display 34 alphanumeric characters instead of 160 ones and zeros).

To add the version number, just put 8 zeros on the front of the 160 bit binary number.

To calculate the checksum:

• Calculate a SHA-256 hash of the RIPEMD-160 hash result
• Calculate a SHA-256 hash of this SHA-256 hash result
• Take the first 32 ones and zeros from this SHA-256 hash result

Append these 32 ones and zeros to the end of the RIPEMD-160 160 bit binary number.

The leading character '1', which has a value of zero in base58, is reserved for representing an entire leading zero byte, as when it is in a leading position, has no value as a base-58 symbol. There can be one or more leading '1's when necessary to represent one or more leading zero bytes. Count the number of leading zero bytes. Each leading zero byte shall be represented by its own character '1' in the final result.

Now, to get the bitcoin address, convert the rest of the 200 bit binary number to base58 using the representation defined here:

Check this out, https://en.bitcoin.it/wiki/Technical_background_of_Bitcoin_addresses

Sure sure, so I went to bitaddress.org and gave them my super secret private key:
a6d72baa3db900b03e70df880e503e9164013b4d9a470853edc115776323a098

They did some magic and gave me this really nifty address:
1Nbm3JoDpwS4HRw9WmHaKGAzaeSKXoQ6Ej

What I want to know is:
How do I magic?

I would just use the source of Bitaddress https://github.com/pointbiz/bitaddress.org/archive/master.zip and enter it in the Wallet Details tab.

This is an awesome thread btw! I've been reading everything and even though I may know a medium amount about bitcoins I still learned quite a few new things.

Amazing!