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Author Topic: A simple bitcoin Q/A. Learn new and interesting stuff about bitcoin.  (Read 6216 times)
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buwaytress
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February 19, 2018, 07:35:31 PM
Merited by DannyHamilton (2), Indrawan77 (1), eddie13 (1), bill gator (1)
 #21


Question :

Did Satoshi write the Bitcoin Whitepaper or write the code for Bitcoin first?
Why did he choose the one he did to do first?


Just to say, I didn't know the answer to this. My first assumption was that he wrote the code first (as the whitepaper has some excerpts of coding) but now looking online I see that v0.1 was released on Jan 8 2009... meaning to say the whitepaper was published at least two months before the first version release...

My guess is that the whitepaper still had to be completed after he compiled his first coding, so would still believe it had to be written first. He had to solve the problems Bitcoin aimed to do (direct, trustless p2p payments)... the whitepaper was not so much a proposal for a way to find the solution, but a proposal to use his creation as the solution.

If I'm wrong, and the whitepaper was, indeed, published first... then he did it to gauge the cypherpunk community's interest to decide if the code was worth completing.

Note: I use third person "he" but only figuratively.

P.S. Thanks for this initiative guys! I'm sure I'll learn from the responses.

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bill gator
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February 19, 2018, 07:49:52 PM
Merited by buwaytress (1)
 #22

Just to say, I didn't know the answer to this. My first assumption was that he wrote the code first (as the whitepaper has some excerpts of coding) but now looking online I see that v0.1 was released on Jan 8 2009... meaning to say the whitepaper was published at least two months before the first version release...

My guess is that the whitepaper still had to be completed after he compiled his first coding, so would still believe it had to be written first. He had to solve the problems Bitcoin aimed to do (direct, trustless p2p payments)... the whitepaper was not so much a proposal for a way to find the solution, but a proposal to use his creation as the solution.

If I'm wrong, and the whitepaper was, indeed, published first... then he did it to gauge the cypherpunk community's interest to decide if the code was worth completing.

Note: I use third person "he" but only figuratively.

P.S. Thanks for this initiative guys! I'm sure I'll learn from the responses.

I would encourage you to research Satoshi's exact quotes on this sort of thing. Your answer is correct, they wrote the code for Bitcoin before releasing the whitepaper. I am unsure about all of the times of release, and which hit public eye first; but at least from their perspective and words this is what happened :

Quote
I actually did this kind of backwards. I had to
write all the code before I could convince myself that I could solve every
problem, then I wrote the paper. I think I will be able to release the code
sooner than I could write a detailed spec. -Satoshi

I would suggest anyone to read some of their original e-mail threads (most of my questions come from sources such as this) : http://satoshi.nakamotoinstitute.org/emails/cryptography/1/

It's funny that you worded it almost exactly the same as them, talking about solving problems, etc.



Question :

In Satoshi's old e-mails they imply that handling as many transactions as Visa should not be a problem.
What does this imply about the development of Bitcoin?
Specifically, what is one parameter that would need to be changed and to what value to accommodate such heavy transaction flow?


Hint: Controversial
Hint 2: Light Math

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February 19, 2018, 07:51:34 PM
 #23

Page 2 Updates :
Update 1 :

Snip
Now that's how you answer a question! Good job buwaytress.
Snip
Sorry but the question has already been answered  Embarrassed.

Update 2 :

-Snip-
This is entirely plagiarized. I think you have misunderstood from what I meant by research. Research≠Copy pasting.
-snip-
This has also been plagiarized. On top of that someone has merited you for that.
You are breaking the forum rules here.
Archive: http://archive.is/uSW73#selection-4709.1-5052.22
Sources used: https://hackernoon.com/blockchains-versus-traditional-databases-c1a728159f79n
https://www.coindesk.com/information/what-is-the-difference-blockchain-and-database/
https://en.wikipedia.org/wiki/Blockchain
You have only rephrased the sentences for the sake of it..

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February 19, 2018, 07:51:39 PM
 #24


Question :

Did Satoshi write the Bitcoin Whitepaper or write the code for Bitcoin first?
Honestly, I didn't know the right answer. I do some research in google and I found that he published his white paper in some day in 2008, and he already said that he still code for bitcoin. I also read that a legend that says "sometime in 2007" (I mean the time that he begin to write the code for Bitcoin. So, it seems that Satoshi writes the code for Bitcoin first.


Why did he choose the one he did to do first?
For this question, I didn't find any answer until now.

Edit : I got the answer, thanks a lot bill gator.
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February 20, 2018, 10:20:39 AM
 #25

I would encourage you to research Satoshi's exact quotes on this sort of thing. Your answer is correct, they wrote the code for Bitcoin before releasing the whitepaper. I am unsure about all of the times of release, and which hit public eye first; but at least from their perspective and words this is what happened :

Quote
I actually did this kind of backwards. I had to
write all the code before I could convince myself that I could solve every
problem, then I wrote the paper. I think I will be able to release the code
sooner than I could write a detailed spec. -Satoshi

I would suggest anyone to read some of their original e-mail threads (most of my questions come from sources such as this) : http://satoshi.nakamotoinstitute.org/emails/cryptography/1/

It's funny that you worded it almost exactly the same as them, talking about solving problems, etc.

Thanks for that, bill! I did spend some time much earlier on reading up on lore... and was fortunate to have been around last year when even more new emails resurfaced in August. I know a lot of people prefer these to be left alone, but history is always important for simple posterity and the giving of context, especially to those who were (and still are) new to Bitcoin.

If only half the projects that launch now put half the effort Satoshi did into Bitcoin... the idea of having a working solution before the white paper hardly exists these days.

Page 2 Updates :
Update 1 :

Snip
Now that's how you answer a question! Good job buwaytress.

Thank you pugman!

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February 21, 2018, 12:47:46 AM
Merited by bill gator (1)
 #26

In Satoshi's old e-mails they imply that handling as many transactions as Visa should not be a problem.
What does this imply about the development of Bitcoin?
Specifically, what is one parameter that would need to be changed and to what value to accommodate such heavy transaction flow?

Satoshi implies that handling the amount of transactions that Visa processes should not be a problem in time because it was expected that computing power would keep pace with network and transaction growth. There were concerns with blocksize limits at the time because the bigger they got the more power that would be required with both upload steams (to broadcast to the network) and computing power (to process the transactions). The blocklimit was set so that mining operations could not out-power single person operations.

Satoshi's emails re transaction processing imply that higher block limits were anticipated and were an expected development of bitcoin. This is controversial as a number of people see off chain scaling as a better method instead of increasing block size.
At 150,000,000 transactions a day that makes 1,041,667 per block (given it can be mined in 10m), and with a transcation size of around 1kb it would need to be just over 1gb. My understanding is that upload/download speeds should be able to keep pace with this size.
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February 21, 2018, 09:58:47 AM
 #27

Yes, Bitcoin does have a solution and it is called the proof-of-work algorithm. So to alter "the message" (a block of transactions in our case) as in the classic Byzantine Generals problem and to make it look authentic by guessing a new nonce, one would need to use more Hash Power than the entire network. Since the current Hash Rate is around 23 million TH/s, to achieve that they would need to buy 1.5 million of Antminer S9.


Btw my proposal remains in force in case you'll find it helpful.

I did not mean to ignore your proposal, but yes that would be excellent. Pugman replies to posts above (https://bitcointalk.org/index.php?topic=2968050.msg30525496#msg30525496), they even responded to you. I will run it by pugman, since it is their thread, but it should not be a problem for us to simply send you a PM when somebody needs a merit or I could keep a little list of people that need their Post # merited. This would help us keep this running without any concern, I appreciate it and accept.

That being said, yes your answer is also correct so I've given you a merit. This means do not attempt to answer the next question.

~
Update 4:
This is a great initiative!

I'm going to monitor this thread on a daily basis because I find it very interesting to read.

Please do not lock this thread on account of running out of sMerits. Since I have 100+ of them left I would be happy to give my merits to those who you find worthy.
I'm not sure I know how to do it the right way (I mean making people know that they were merited by you actually) but I think you guys can figure it out.
Keep up the great work!
Sure you can handout the merits to users who answer the questions correctly. We'll just announce that if we run out of merits,some one else is free to merit the users. Thanks for your feedback. Cheesy
~

Thank you for accepting my proposal, bill gator and pugman! I will be happy to help you with this great project. And thank you for the acknowledgement of my answer and rewarding it with a merit.

While researching the subject I was asking myself what would really happen if a "bad person", a saboteur, had managed to gain more Hash Power than the entire network? Would this be the end of Bitcoin? OR Would they be just able to delay a transaction by 10 minutes and that's all they can do? I would appreciate very much if someone could give me an explanation on this. Maybe you can even announce it as another question if you will. Thanks again for this great topic!

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February 22, 2018, 04:56:04 AM
 #28

A'right here's another question :
Question : What is the Difference Between a Blockchain and a Database?
This is yet another easy question but again people don't know about this. I am looking for some main points, basic explanation is not what I am looking for!

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February 22, 2018, 09:01:30 AM
Merited by Hannahanto (1)
 #29

A'right here's another question :
Question : What is the Difference Between a Blockchain and a Database?
This is yet another easy question but again people don't know about this. I am looking for some main points, basic explanation is not what I am looking for!
Blockchain
A digital ledger in which transactions made in bitcoin or another cryptocurrency are recorded chronologically and publicly and it is used to record transactions across many computers so that the record cannot be altered retroactively without the alteration of all subsequent blocks and the collusion of the network. Originally developed as the accounting method for the virtual currency Bitcoin.

Database
Is a collection of information that is organized so that it can be easily accessed, managed and updated. One of the example on this is spreadsheet. SO it seems Bitcoin has a transaction  Database will record on it.

Blockchain as a permanent database, each time a block gets completed, a new one is generated. There is a countless number of such blocks in the blockchain, connected to each other.
For a blockchain database, each participant maintains, calculates and updates new entries into the database. All nodes work together to ensure they are all coming to the same conclusions, providing in-built security for the network.

correct me if i'm wrong.. Grin Grin

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February 22, 2018, 09:24:55 AM
Merited by pugman (1)
 #30

Instead of rephrasing this link and talking about architecture:
https://www.coindesk.com/information/what-is-the-difference-blockchain-and-database/
I will tell you what I know.
A database is online, but it is kept there by a server computer, so it is centralized by definition. If I have a database, I control it and I can manipulate it as I see fit. It can be hacked or changed by others.
A blockchain is decentralized, and it is on hundreds or thousands of computers, based on the popularity of the blockchain. Some, such as bitcoin blockchain is very popular due to the high price, and some others are not so. Blockchain is an immutable public ledger and it cannot be hacked, modified, stolen or manipulated. If you own 51 percent of the blockchain though, then it could be a problem as they can all pool and do something nasty with that.
There you go, I hope you like what I wrote because I tried to write it as simple as possible.
Maybe there should be a guide like "Bitcoin for idiots" or something like that. Being too hard or technical is a wall in the way of the public.

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February 22, 2018, 10:22:41 AM
 #31

A'right here's another question :
Question : What is the Difference Between a Blockchain and a Database?
This is yet another easy question but again people don't know about this. I am looking for some main points, basic explanation is not what I am looking for!
In database everyone sends information into an intermediary, that has a single version of a truth, which helps to avoid disagreement between different parties while communicating through a centralized database. Blockchain has another way to solve the data coordination problem and make sure disagreements won't occur, as it is decentralized and there are multiple parties that share a single truth and none of those parties may be considered as central - the consensus has to be reached. So the individual transactions are put into blocks, and the chain of those blocks must ensure consensus.
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February 22, 2018, 11:27:03 PM
 #32

A'right here's another question :
Question : What is the Difference Between a Blockchain and a Database?
This is yet another easy question but again people don't know about this. I am looking for some main points, basic explanation is not what I am looking for!

       Blockchain is a continuously growing list of records that consist of several decentralize nodes. It is the worlds leading software platform for digital assets which is originally developed as the accounting method for virtual currency.
     While Database is an structured set of data held in a computer. It is an organized collection of information so that it can be easily accessed,managed and updated.
     Blockhain has a core characteristics of being decentralizes and trustless. Data can be shared accross the network without the need of an intermediary to validate or authorize it.

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February 24, 2018, 06:06:01 PM
 #33

Question : How exactly does a 51% attack work?
This might be a hard question to answer but take your time, as long as your answer is correct and you are the only one who has answered, you'd be declared winner. Get your things going.
I'll update the other posts in 24 hours.

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February 24, 2018, 06:26:00 PM
Merited by pugman (1)
 #34

Question : How exactly does a 51% attack work?

When I read your post I immediately thought about someone who has 51% mining power.
As stated  in Bitcoin whitepaper " The system   is   secure   as   long   as   honest   nodes   collectively   control   more   CPU   power   than   any
cooperating group of attacker nodes."

So I believe this is the case.
Well, from my understanding in this case the attackers could just make fake transfers in past blocks to their address. As they would mine faster than the network, this "alternative block" would became the real block, as it is the longest chain. Then the whole network would confirm it later on.

They could even decide which transactions get confirmed or not. And double spend their own coins too.

I made a few google searches, to post a better answer:
https://learncryptography.com/cryptocurrency/51-attack
" 51% attack doesn't give you full power over the bitcoin network. The farther back in the blockchain transactions are, the more secured they are against this kind of attack. Realistically, an attacker would only be able to modify transactions within the past few blocks. They would also not be able to make new coins out of thin air - except those received as block mining rewards as usual.

It is an interesting concept because it is theoretically possible; the network is free and open, so if someone were to have enough computational power (which would cost a huge amount by itself), there is no bitcoin authority to stop them from doing so. In the event that such an attack successfully takes place, it is likely confidence in the currency would be lost and it’s value as a currency would decline rapidly. "

Good info here too.
https://bitcointalk.org/index.php?topic=52388.0;all


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February 24, 2018, 07:01:51 PM
Merited by pugman (1)
 #35

What @bitmover has said is totally accurate. But I just want to give my answer too as I'm excited because I learnt this just now while searching for the answer of this, and have never been aware of anything like this before.

So, a more clear and simple answer to the question, "How exactly does a 51% attack work?" is that a person or a group of people having control over 51% or more hash power can easily manipulate the transactions, meaning they can prevent other miners from mining any blocks and do it themselves to earn all the block rewards and they can pretty easily double-spend a transaction done by themselves, or prevent other transactions to get confirmed.
However, they cannot do much with already mined blocks and transactions. The more the time distance of a transaction/block is, the less are the possibilities for the attackers to change or reverse it.
Such an attack can be done even with less hash power but the probability of success would be much less then.

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February 24, 2018, 08:19:35 PM
 #36

In Satoshi's old e-mails they imply that handling as many transactions as Visa should not be a problem.
What does this imply about the development of Bitcoin?
Specifically, what is one parameter that would need to be changed and to what value to accommodate such heavy transaction flow?

Satoshi implies that handling the amount of transactions that Visa processes should not be a problem in time because it was expected that computing power would keep pace with network and transaction growth. There were concerns with blocksize limits at the time because the bigger they got the more power that would be required with both upload steams (to broadcast to the network) and computing power (to process the transactions). The blocklimit was set so that mining operations could not out-power single person operations.

Satoshi's emails re transaction processing imply that higher block limits were anticipated and were an expected development of bitcoin. This is controversial as a number of people see off chain scaling as a better method instead of increasing block size.
At 150,000,000 transactions a day that makes 1,041,667 per block (given it can be mined in 10m), and with a transcation size of around 1kb it would need to be just over 1gb. My understanding is that upload/download speeds should be able to keep pace with this size.

I apologize for taking so long to reply and merit you. I've been running around like a chicken with their head cut-off, very busy trying to get a small bitcoin mining operation started among other things.

Your numbers are a little different from mine, but I was going off of the # of transactions that were happening back then, so I'll give it to you. Your reasoning, logic and everything else arrives you at the right conclusion. It seems like pugman has been running the questions for now, so I won't hop in the way; just wanted to give credit where it is due.

Correct, Merited I'll post another question when Pugman seems stumped, out of ideas or requests for me to do so.

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February 25, 2018, 09:24:13 PM
 #37

Question :A bitcoin transaction with 6 confirmations is usually considered to be secure. Why is it so?
I have 2 previous answers to update, I'll try my best to update it within 48-72 hours along with the answers for this question.

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February 25, 2018, 09:55:37 PM
 #38

Question :A bitcoin transaction with 6 confirmations is usually considered to be secure. Why is it so?
I have 2 previous answers to update, I'll try my best to update it within 48-72 hours along with the answers for this question.

After 6 confirmations it is safe from any attacker as the transactions won't be vulnerable to race or finney attacks and 6 confirmations is enough for large amount therefore it is usually considered to be secure.
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February 26, 2018, 01:41:03 AM
Merited by pugman (1)
 #39

Question :A bitcoin transaction with 6 confirmations is usually considered to be secure. Why is it so?
I have 2 previous answers to update, I'll try my best to update it within 48-72 hours along with the answers for this question.

As mentioned in bitcoin wiki, only 6 blocks or 1 hour is enough to make reversal computationally impractical. Generally when it reaches 6 confirmations, there will be far less possibility for the transaction to be reversed, thus it is secure. 10 minutes is the average time needed to find a block. It will be very very hard for attacker to overtake the blockchain from a fork six blocks prior.

Also, in Satoshi's paper (https://bitcoin.org/bitcoin.pdf), it shows:
Code:
P < 0.001
q=0.10   z=5
q=0.15   z=8
q=0.20   z=11
q=0.25   z=15
q=0.30   z=24
q=0.35   z=41
q=0.40   z=89
q=0.45   z=340

If the attacker has a small percentage of hashing power then 6 blocks will be enough to ensure the secure of the transaction.

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February 26, 2018, 04:05:10 AM
 #40

Question :A bitcoin transaction with 6 confirmations is usually considered to be secure. Why is it so?
I have 2 previous answers to update, I'll try my best to update it within 48-72 hours along with the answers for this question.

After 6 confirmations it is safe from any attacker as the transactions won't be vulnerable to race or finney attacks and 6 confirmations is enough for large amount therefore it is usually considered to be secure.

That is false. On July 4, 2015, there was a 6 block orphan chain, and those blocks were accepted by almost all wallet software. It was a result of SPV mining (mining based off of just the block header, without verification. Can give a small advantage in letting them find a block a bit faster) ontop of an invalid block that signaled a v2 block (the network had soft forked into v3 blocks). It's entirely possible that a transaction could have been put in the first orphan block, got to 6 confirmations, and then went back to 0. The mempool could have had more higher fee transactions in the process, making the earlier mentioned transaction have a slower confirmation time. This allows an attacker to theoretically double spend with a higher fee. It is an extremely rare scenario, but it is false to assume that it is entirely safe from any attacker. There were fortunately no double spends from July 4th.

More reading:

https://bitcoin.org/en/alert/2015-07-04-spv-mining
https://en.bitcoin.it/w/index.php?title=July_2015_chain_forks&redirect=no

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