tag:blogger.com,1999:blog-6628169086519392271.post8535787723515109417..comments2023-12-08T01:18:33.083-08:00Comments on ImponderableThings (Scott Driscoll's Blog): How Bitcoin Works Under the HoodScott Driscollhttp://www.blogger.com/profile/07332816619406995078noreply@blogger.comBlogger84125tag:blogger.com,1999:blog-6628169086519392271.post-16273106739446691952018-03-06T08:09:34.728-08:002018-03-06T08:09:34.728-08:00Amazing video. Well done !Amazing video. Well done !Elmahttps://www.blogger.com/profile/07615014717728091558noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-48528897076552833542018-02-22T10:29:00.834-08:002018-02-22T10:29:00.834-08:00what are the effects or consequences when a bitcoi...what are the effects or consequences when a bitcoin is / will be backed by real assets like the Petro in Venezuela and the yuan in China. more stability !!!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-62228027746488645432017-11-27T05:29:11.726-08:002017-11-27T05:29:11.726-08:00Great explanation, thank you.Great explanation, thank you.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-59741848312561769132017-11-11T07:54:30.342-08:002017-11-11T07:54:30.342-08:00Within block order is determined by miner that cre...Within block order is determined by miner that creates block. Two transactions from valid one party are valid within one block as long as they don't break any rules. Blocks are checked for validity before being accepted by other miners, so it would be useless to create an invalid block. Winning the race to find the hash only pays out if your block is accepted.Scott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-48371737450755234412017-11-11T06:57:17.242-08:002017-11-11T06:57:17.242-08:00Hi Scott,
By far the best explanation I found. We...Hi Scott,<br /><br />By far the best explanation I found. Well written, Thanks.<br /><br />One question:<br />1) How the order in the block is determined? What if Alice makes one more transaction to another party and it goes into the same block and before Bob's transaction. <br />What is preventing this from happenning?Anonymoushttps://www.blogger.com/profile/00414459582375989213noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-69959328190528848172017-08-15T04:45:03.699-07:002017-08-15T04:45:03.699-07:00only miners / bookkeepers store the transactions. ...only miners / bookkeepers store the transactions. It is hundreds of GB and growing--it's a concern.Scott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-91869910745133853322017-08-15T00:08:44.732-07:002017-08-15T00:08:44.732-07:00How is it possible for every user to store that hu...How is it possible for every user to store that huge database of all the transactions ever made? It should be hundreds or even thousands Gb and growing.Anonymoushttps://www.blogger.com/profile/04055071592699167134noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-4612604406730012522017-08-10T02:04:45.687-07:002017-08-10T02:04:45.687-07:00Probably THE best explanation out there.
Wonderful...Probably THE best explanation out there.<br />Wonderful work. Keep it up.<br /><br />P.S: If interested in having it translated to Arabic, I would gladly do it. Just reply here :)<br /><br />Cheers, and thanks againAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-7314408132089450082017-05-09T05:32:06.063-07:002017-05-09T05:32:06.063-07:00Transactions don't confirm immediately, and it...Transactions don't confirm immediately, and it's in that window before they confirm that there's a risk of double spending.Scott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-6182044383817071072017-05-09T04:51:01.813-07:002017-05-09T04:51:01.813-07:00I have a problem understanding Double Spending in ...I have a problem understanding Double Spending in Bitcoin. As if i have 5BTC and i made a transaction of 5BTC to some other person my BTC will be now 0. Then how i could make another transaction thats not possible and also once the transaction is made there no way it can be cancelled please reply asap. <br />thankyouanubhavnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-24859762792192718552017-04-24T08:33:53.696-07:002017-04-24T08:33:53.696-07:00this video gives me a lot insight of Bitcoin. much...this video gives me a lot insight of Bitcoin. much thanks!<br /><br />few questions:<br />1. as block chain is a distributed ledger on each node, then how much data space does each node need? sounds enormous!<br />2. will there some 'digital discrimination' on Bitcoin, due to slow network connection and less computing power?<br />3. in your article, a new bitcoin user need to download Bitcoin wallet, and download every transaction ever made in history and ... if the new user found some transaction invalid, what will happen to him/her and to the whole Bitcoin users?<br />4. what's the back-end algorithm to keep the '10 minutes' verification time?<br />5. when a node finds another longer chain out there, then it will switch to it. how does a node compare its chain length with another? because there will be tremendous fork chains out there, how long will it take to cross compare all of them?<br />6. the last question, transaction confirmation. you say it's better to wait 1 up to 6 blocks to make the final confirmation. it seems unacceptable and the most weak point for bitcoin. let's say if there is no new transaction at the time, well the last transaction block can be manipulated arbitrarily by the most powerful person/machine?Anonymoushttps://www.blogger.com/profile/15067164097931510285noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-5340857385211129752017-04-24T07:56:57.222-07:002017-04-24T07:56:57.222-07:00no no no, this problem does not exist. in your cas...no no no, this problem does not exist. in your case, the number of small portion of people ( people in the country) is less than outside, once the connection restored, all of your transactions will be dismissed and put into unconfirmed transaction list to be verified again, and finally they will all be verified and put into the global block chain later.Anonymoushttps://www.blogger.com/profile/15067164097931510285noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-19105671493698264792017-03-25T19:24:17.436-07:002017-03-25T19:24:17.436-07:00Hi Scott, this is a great video. Do you have any o...Hi Scott, this is a great video. Do you have any other material to explain ethereum on same lines - how does smart contract work on blockchain?Anonymoushttps://www.blogger.com/profile/17480475510277432209noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-55720322425533163092017-01-09T11:02:11.614-08:002017-01-09T11:02:11.614-08:00ThanksThanksAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-68379537596677743362017-01-08T21:30:35.325-08:002017-01-08T21:30:35.325-08:00it's adjusted to maintain a 10 minute block ti...it's adjusted to maintain a 10 minute block time automatically. Find out all the gory details: https://bitcoin.org/en/developer-guideScott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-19509916368036462612017-01-08T21:11:12.374-08:002017-01-08T21:11:12.374-08:00Excellent Article. Very helpful. Thanks.
Question...Excellent Article. Very helpful. Thanks.<br /><br />Question - How does the target (or threshold) gets determined?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-11731824284557760222016-12-29T03:43:54.305-08:002016-12-29T03:43:54.305-08:00Maybe I can release a 2 second version in Dutch.. ...Maybe I can release a 2 second version in Dutch.. ;-) <br />No no just kidding... If you want to see in translated into Dutch (Belgium) just ask... It will be a good practise for me or my daughter who is studying for translator.. Gunter Meynenhttps://www.blogger.com/profile/06052305101869380492noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-34912126123207194742016-12-09T05:11:10.687-08:002016-12-09T05:11:10.687-08:00Hi Scott,
First of all the best article i found...Hi Scott,<br /> First of all the best article i found on Internet on Bitcoin. <br />I have few queries. <br />Request you to please throw some light on it:<br /><br />- Lets say Alice sends money to Bob. ( The transID is xxxxxx )<br />The value of PrevOut (Previous transaction from where Alice got the money) is say yyyy.<br /><br />- The transaction(xxxx) gets broadcasted and selected lets say in the latest block in the blockchain.<br /><br />- Now after few successive blocks (lets say 10 blocks) Alice creates a new transaction(zzzz) indicating payment to a different user called David and uses the same old transID as the value of PrevOut (yyyy) and broadcasts it.<br /><br />My questions are:<br />- How does the miner now that this transaction(yyyy) has already been used 10 blocks ago ? Of course he can use the transaction chain to identify that this transaction was present in a block which is 10 block behind the current block but since there will be so many transactions must have happened in those 10 blocks the miner will get to spend immense amount of time to validate it. In your blog you mentioned that it takes 24 hours to validate the complete block chain. So during a new block creation how much time it takes a miner to typically validate that a new trasaction's prevOut value is not present in all the previous blocks ?<br /><br /><br />Anonymoushttps://www.blogger.com/profile/05157215621602729653noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-13849320121628451952016-10-25T02:31:28.796-07:002016-10-25T02:31:28.796-07:00Unfortunately PS only has a subscription model rig...Unfortunately PS only has a subscription model right now. I'm pretty sure there's no "learning for free" suggested anywhere, except that you can get a free trial. Scott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-55069480216765077352016-10-06T00:56:22.721-07:002016-10-06T00:56:22.721-07:00Very nice. Putting the course on pluralsight is no...Very nice. Putting the course on pluralsight is not as nice though. Any site which promotes "learning for free" and asks your financial details on the second page is not to be trusted IMHO. <br />Would be happy to follow (and pay for) the course on a pay-per-use basis....Mario Alemihttps://www.blogger.com/profile/09704690113505168789noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-4057815996216606132016-07-25T12:05:44.998-07:002016-07-25T12:05:44.998-07:00Great article! It helped me a lot to understand ho...Great article! It helped me a lot to understand how Bitcoin works deeply. Thanks!Jéssica C.https://www.blogger.com/profile/13652090041363033051noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-9262463923765872542016-06-25T14:42:51.746-07:002016-06-25T14:42:51.746-07:00James
I don't know if this helps, but here yo...James<br /><br />I don't know if this helps, but here you go:<br /><br />In the simplest form, you start with a SEED. (For Bitcoin this is the account password, which you can create, or have the wallet create for you).<br /><br />The FUNCTION starts with the SEED and generates the RESULT. (For Bitcoin this is the Bitcoin account).<br /><br />Many functions are reversible, where you can start with the RESULT and get the SEED.<br />Example Reversible Function: RESULT = SEED + 3<br />So, if SEED=4, RESULT=7.<br />And to reverse, SEED = RESULT - 3 = 7 - 3 = 4.<br /><br />For Bitcoin the functions are irreversible. You create the account by applying 4 such functions in a row.<br /><br />To see them all together look here: https://www.bitaddress.org/<br /><br />Separated the 4 functions are:<br />Memorable Text=>SHA256Digest<br />SHA256Digest=>Bitcoin Password (aka private key)<br />Bitcoin Password=>Public Key<br />Public Key=>Bitcoin Account.<br /><br />To see these function separately coded as Excel functions in Visual Basic, you may review this: http://bitcoinspreadsheet.blogspot.com/p/wallet-programming-contest.html. Caveats: 1. Visual Basic is a very inefficient language for this, so it will take A VERY LONG TIME for the cells to refresh. It has been created for demonstration purposes only. 2. The contest prizes mentioned are no longer offered. 3. The spreadsheet should be usable as a wallet, but has not been vetted. (Despite the large prizes, programmers did not want to confirm it.)<br /><br />Hope this helps,<br />JohnAnonymoushttps://www.blogger.com/profile/12408650682915890075noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-71975049270129506982016-04-13T13:52:13.714-07:002016-04-13T13:52:13.714-07:00So BitCoin actually uses TWO blockchains? One for ...So BitCoin actually uses TWO blockchains? One for the transactions and one for the order of the Blocks? AND: When a signature gets validated, it's transaction will be added to the transaction blockchain? And later added to a block which is added to the chain?Anonymoushttps://www.blogger.com/profile/00911706504516838032noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-38314785736915213752016-03-06T07:14:54.651-08:002016-03-06T07:14:54.651-08:00Let me try to define terms a little more precisely...Let me try to define terms a little more precisely. By random number, I mean the nonce that goes into the hash function for the current block you're trying to solve along with the hash for the previous block and transactions. The full result of that hash needs to be smaller than the current target. So, h(last_block_hash, nonce, transactions) < t. The random number for the last block isn't involved. Scott Driscollhttps://www.blogger.com/profile/07332816619406995078noreply@blogger.comtag:blogger.com,1999:blog-6628169086519392271.post-17939887428110489622016-03-06T06:52:00.348-08:002016-03-06T06:52:00.348-08:00Hi Scott,
thanks for creating that good video. It ...Hi Scott,<br />thanks for creating that good video. It helped me to understand how Bitcoin works, but I still have one question.<br /><br />You said, that you need to find the correct random number of the current block to be allowed to add your block. But with adding your block you actually know the random number of the new last block. So you can easily "guess" it and add another and another... What did I get wrong?<br /><br />Thanks,<br />PeterAnonymousnoreply@blogger.com