Hola amigos. Les comparto este tutorial que estoy creando en youtube para programar nuestra propia blockchain. Espero que sea de su agrado. https://youtu.be/x0rc90gHWKkExcelente tutorial, cabe destacar que esto es programación orientada a objetos y una lastima que la programación sea en código Go, creo que hubiera sido mucho mejor el ver la creación de una cadena de bloques con JavaScript. A mi me gustaria crear una moneda con las siguientes caracteristicas.
Limitada a 100 millones.
Minable con Raspberry
¿Por donde puedo empezar?
Para esto no tienes que crear un blockchain desde cero, para esto te conviene hacer un clon de la moneda que quieras y modificar el parámetro de el limite de la moneda. |
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This is a known issue and unfortunately it cannot be fixed without a fork. The issue lies with the format of a segwit transaction itself. A segwit transaction, under some circumstances, can be interpreted as either a 0 input, 1 output transaction, or as a witness transaction. Since getrawtransaction fetches transactions from blocks themselves or from the mempool, the transaction must be a valid network transaction and thus witness serialization can be attempted safely as a first step and only deserializing as non-witness if the witness deserialization fails.
However, decoderawtransaction behaves differently as it is intended to be used during the transaction creation steps. This means that it must be able to handle 0-input, 1 output transactions (which are inherently non-witness) as users may create a 0-input, 1 output transaction, decode it, and then pass it to fundrawtransaction to get inputs. But because some 0-input, 1 output transactions can be interpreted as witness transactions, and some witness transactions can be interpreted as 0-input, 1 output transactions, decoderawtransaction does not always succeed to decoding a transaction correctly. It uses some heuristics in order to decrease the number of false decodings, but sometimes, as you can clearly see, it's wrong.
Thanks, very informative. I didn't know decoderawtranscaction was intended to be used during transaction creation steps. Fortunately, if you know that a transaction is witness you can set the iswitness argument (added in 0.16) to true to tell it explicitly to decode the transaction as witness. You can set it to false for non-witness decoding. Not setting it uses the heuristics. So your command will be something like: bitcoin-cli decoderawtransaction <tx> true
Yes, this does indeed work! The documentation found at https://bitcoin.org/en/developer-reference#decoderawtransaction doesn't list the second parameter. According to the documentation decoderawtransaction only takes a single parameter. Guess the documentation isn't up to date here. One last question about the heuristic in this specific case: It's pretty clear the assumption made this was a transaction without witness data is wrong based on the fact it's reporting a negative value as an amount. So shouldn't the "heuristic algoritm" reassess itself when the output generated was clearly wrong: Input -> Trying as non witness -> Output is valid -> Done
Input -> Trying as non witness -> Output is invalid -> Trying as witness ->Output is valid -> Done
I might be oversimplifying things here but it seems to me this would lead to a lot less incorrect assumptions from heuristics.
Nice to see this get fixed, as you commented before, no one talk about that second parameter for decoderawtransaction, the true at end makes the difference. avoiding the problem. Maybe you can change the topic to Fixed and close the thread now.  |
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...so they are still part of the public blockchain.
Yes, they are part from the blockchain, and for sure explorers will have to upgrade their platforms to give information about the, Most likely they're too lazy to add Bech32 support unless many people request for it or have plan to commercialize their API.
And this feels weird, maybe explorers think that was just a inoffensive soft fork and now it feels like an invasion to the main chain. So lets hope block explorers upgrade their engines. |
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I can see two things in this scenario... 1.- An enormous blockchain... at that block rate after one year we will have a big number of blocks, that mean a heavy blockchain: 2.- A massive processing... blocks each second mean the miners have to solve them fast... and transmit the information about the new block onthe network each second is another important fact. At start could be simple, but with time could get really heavy. |
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Hi, I want to learn exact formula to get blocks hash where nonce is compatible for network's target requirements. For example, I want to see formula like this. SHA256 ("Previous Block Hash + Nonce + Merkel Root + Client Version") Thank you very much. Have a great day  This is what you are looking for: A block header contains these fields:
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 For example, this python code will calculate the hash of the block with the smallest hash as of June 2011, Block 125552. The header is built from the six fields described above, concatenated together as little-endian values in hex notation: >>> import hashlib
>>> header_hex = ("01000000" +
"81cd02ab7e569e8bcd9317e2fe99f2de44d49ab2b8851ba4a308000000000000" +
"e320b6c2fffc8d750423db8b1eb942ae710e951ed797f7affc8892b0f1fc122b" +
"c7f5d74d" +
"f2b9441a" +
"42a14695")
>>> header_bin = header_hex.decode('hex')
>>> hash = hashlib.sha256(hashlib.sha256(header_bin).digest()).digest()
>>> hash.encode('hex_codec')
'1dbd981fe6985776b644b173a4d0385ddc1aa2a829688d1e0000000000000000'
>>> hash[::-1].encode('hex_codec')
'00000000000000001e8d6829a8a21adc5d38d0a473b144b6765798e61f98bd1d' Source: https://en.bitcoin.it/wiki/Block_hashing_algorithm |
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Muchas de estas restricciones pueden ser elminadas con una membresía de cobre (Copper Membership). En particular, pueder poner una firma de nivel Miembro si tienes una membresía de cobre.
Creo que aquí es en donde está el truco, al final de cuentas si un usuario paga puede tener una cuenta con cero publicaciones pero la capacidad para hacer publicaciones como si fuera una cuenta member. Por $13 dolares: Te permite publicar imágenes aunque seas newbie, se reduce el limite de tiempo entre cada acción y te otorga algunos de los beneficios del rango Member. Es importante comentar que la membresía de cobre no te da impunidad, aun que se pague por la membresía se deben de seguir las reglas del foro. -Puedes ser suspendido si rompes las reglas. No recibirás un trato especial.
-Nada garantiza que la membresia dure para siempre o que te ofrezca los mismos beneficios a futuro.
-No hay reembolsos. Fuente: https://bitcointalk.org/index.php?action=credit;promote
..Pero si eres incapaz de publicar nada que valga la pena, entonces nunca debieras subir de rango y no lo harás: Este foro no es para ti.
Al final concuerdo totalmente contigo paxmao, da gusto ver publicaciones de calidad en ves de puro spam. Te llevas 1 merito y DdmrDdmr se lleva 2 por publicarlo primero, gracias por mantener a la comunidad de habla hispana informada  |
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Happens to all, looks like mods are making a great job here cleaning the forum, and that's great because this is a huge forum, and fill it with trash is not the right way for knowledge. Just remember, sometimes is your post what's get deleted, other times is the full thread. So, the best way to avoid this is to not post on the spam threads or threads who you think mods can delete, and to not get out from the thread topic. That's the right way to roll.
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"I'm sure that in 20 years there will either be very large transaction volume or no volume." -- Nakamato Satoshi
Is Nakamato Satoshi the same as Satoshi Nakamoto? I'd like to see the source of where he said that if you have it. It's an interesting quote. I've touched on something similar in a thread I made a while ago, in which I explained that we don't truly know which scenario is going to unfold in the future. Here's the original quote: Right. Otherwise we couldn't have a finite limit of 21 million coins, because there would always need to be some minimum reward for generating. In a few decades when the reward gets too small, the transaction fee will become the main compensation for nodes. I'm sure that in 20 years there will either be very large transaction volume or no volume.
People should really go back and read his old posts here on the forum. They provide a lot of insight into why Bitcoin was designed like it was. As it turned out, the block size limit Satoshi added is a very important mechanism for generating the fees required to compensate miners. Without some mechanism to disincentivize spam and drive fees up, we would have a tragedy of the commons situation, where everyone takes up block space without paying for it. That can't work where there is a limited supply of coins -- with each halving, miners get less and less subsidy. Eventually, they'll only get transaction fees. We need to incentivize miners to secure the network. Thanks to share the source from that satoshi's quote, but in that point he was talking about the mining rewards, lets remember the block reward get divided by half each X time, so, at end the block reward will be the transaction fees. Bitcoin is not only crypto,we have almost 1800+ crypto currencies at the moment some have better properties than bitcoin so we can handle all the world's transaction with cryptos but not only with the bitcoin so in future new cryptos will evolve and people will start uses the appropriate cryptos for their needs.
You have a good point here, maybe with bitcoin will be hard to compete with visa TPS, but with all the altcoins maybe is possible. Would be smart to develop an altcoin who allow 6Million of transaction/minute, that could be a nice competitor to banks, but can you imagine how huge would be that blockchain? 1Gb blocks  |
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I'm not sure if satoshi makes bitcoin as an alternative payment system, or with the intention to create the best and most used payment system, but this second option is impossible by the bitcoin nature and i will explain why.
if you are looking for something perfect without any downsides and 0 problems then don't look for it in this universe. what you are seeking is not found anywhere but in an alternate universe!... lol, maybe you are right, i'm searching perfection in the wrong place. But think about it, it could be perfect if the main focus of the coin where to be the main transactions system. But after read all your comments looks like that wasn't the focus. At end only time can tell us what was satoshi's vision. |
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I'm not sure if satoshi makes bitcoin as an alternative payment system, or with the intention to create the best and most used payment system, but this second option is impossible by the bitcoin nature and i will explain why. If bitcoin want to become the #1 transactions and payment system it would have to be really more powerfull. If we compare the daily transactions banks vs daily transactions bitcoins, then you will understand why i call satoshi visionless: TPS: Transactions Per Second. While bitcoin have blocks each 10 minutes with 2500 transactions aprox, that give us an averange of 4 TPS. We are far away to compete with banks, bitcoin by it self is not able to handle all the transactions the world have, so, maybe is good time to think about the next steps, and get some big goal like substitute banks with btc. But no one say it would be easy |
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THE PROBLEM WHEN I AM ENTERING THE BACKBUP PHRASE ITS SHOWING WRONG
Then you don't have a valid backup, no backup = no coins. On the description of your problem is the issue, if you don't have access to the privatekeys then you don't have access to the coins, easy as that. Just imagine what will happen if any one coud spend coins without having access to the privatekeys, lol, any one would be able to spend others coins. And that isn't a good deal at all for the coin. would be like the carding, some one spending money from your card using your name. That's a scam, so, the best thing you can do is to try to recover those privatekeys, find the right way to load your backup, that should be the way. |
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What are your practices to ensure a safe data keeping including all of your wallets (not talking about normal malware which can redirect your copy paste BTC address to another one) but I am talking in a situation where all your data is locked from a Ransomware. In case you did a backup every week of the entire image disk, the only thing you would lose is a week of data. Of course keep the image recovery in an external hard drive.
Any better security practices against Ransomware ?
The backups are important, not only to save your ass from a ransomware, there are one hundred ways your pc can get fucked up, Ransomware is just one of those ways. But i'm here with a solution for you. Use Linux and avoid Ransomware, you can have a pc with half disk on linux and half disk on windows, that way of you are doing some job stuff you can use windows, and if you want to navigate on the web or do something 'risky' then you can use linux. Good security practices are the way to avoid all kind of viruses... |
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Creo que faltaron algunos términos importantes para este mundo de las criptodivisas: Mining: Proceso de minado para obtener coins y confirmar bloques Block: Definicion de bloque Staking: Proceso de minado... Veo que ya tienes POS y POW, pero te falto PoC (Proof of Capacity. Proof of Capacity PoC) Ponzi: Los esquemas ponzi estaban muy de moda antes de que aparecieran los icos. Y pensare en el transcurso del dia en que mas se podría poner en la lista. Pero buen trabajo. |
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deberian de tomar muy encuenta la seguridad de la misma. alguna vulnerabilidad esta sucediendo con estos exchanges japones
La seguridad misma es algo que se tiene muy presente en el momento de desarrollar un proyecto como lo es un exchanger, el problema es el manejo de esta y el manejo de los fondos, como podemos aprender de este hackeo y de varios hackeos en el pasado, es riesgoso tener las monedas en el servidor ya que si este es vulnerado entonces tanto las monedas como la información de los clientes sera expuesta. Por eso lo que yo recomendaría es usar el sistema de hot y cold wallet. estos exchangers deberían tener un 80% del capital en cold wallet y el otro 20% en hot wallet, transacciones minimas que fluyan sin problemas mientras que las transacciones grandes tomen un proceso de 6 a 12h |
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Poloniex support: "Thanks for letting us know that the explorer is back up. We are currently undergoing unscheduled maintenance with the CLAM wallet. Our engineers are working to bring this back online as soon as possible."
I'm going to ask them if it is because of dust or not. And the problem isn't only poloniex, yesterday i take a look to shapeshift and they have blocked clam transactions too, any clue about what's happening with clam? I read the release notes from the new bitcoin core (0.16.3) and they say they fixed a bug who should affect all other coins (since alts comes from bitcoin code), so, looks like clam devs have some work to do, and some stuff to fix. |
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I would say BCH and Monero, those two coins for me have some nice future.
BCH have a nice future because is like bitcoin but with bigger blocks, and in future terms bitcoin will need bigger blocks to handle more transactions in the same time. And Monero have nice future too because the anonymity side of the coin. At end internet need that anonymous coin, and Monero is the solution for that issue, that's why i think those coins have nice future.
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Our exchange was founded in 2013, in the past 5 years, we did not pay much time or money in its promotion. The whole company were focusing on technology at that time.But now as you know,due to some known or unknown things, we are losing users everyday... Some loyal customers advised us to do some promotions to attract more new users. I am here to look for help, can anyone tell me how can I promote our exchange? Of course we will keep focusing on the technology at the same time.
Well, i think the best option is to promote it with a signature campaign on this forum, campaigns aren't cheap at all, but they are an efficient way to promotion any cryptos related business. Other way would be with Google and Facebook campaigns, you know those kind of campaigns where you pay each click you get, but those companies say each click is a potential client, so, sometimes worth it. |
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Buen día colegas argentinos, se que la andan pasando muy mal ahora con el tema del dolar, así que les traigo otra opción para comprar bitcoin desde argentina con la moneda nacional: https://localbitcoins.com/es/lugares/595859115/argentina/Ahí encontraran compradores y vendedores de BTC por moneda argentina, espero que les sea útil y animo argentina, son tiempos difíciles pero hay que ver para adelante! |
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