Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [blockchain]

This tag should be used for questions pertaining to the blockchain. The blockchain is a list of all transactions that have occurred using the Bitcoin currency. It consists of blocks which are linked to each other, and each block consists of transactions. DON'T USE THIS FOR THE SERVICE NAMED 'blockchain.info'!

1
vote
1answer
146 views

Is PBFT a consensus algorithm?

Can we consider PBFT (Practical Byzantine Fault Tolerance) as a consensus algorithm ? And if yes, How does it work? And is it similar to other consensuses such as PoW, PoS or PoA ? Or it is totally ...
0
votes
1answer
35 views

Block Chain length/size may one day get unwieldy to compute

Is it possible that the length of the existing block chain will one day become unwieldy to compute? Would it make more sense that the chain would somehow be rolled up like normal bank ledgers do with ...
0
votes
1answer
37 views

IBM Blockchain platform specifications

So I saw an ad for IBM's blockchain platform, specifically the campaign they have to "turn plastic into money" by way of exchanging recyclable materials for digital tokens. I was just wondering if ...
0
votes
1answer
18 views

Why the block's order in blockxxxxx.dat is different from blockchain.info

I parsed the block00000.dat using python code: class BlockFile: def __init__(self, block_filename): self.block_filename = block_filename self.blockchain = open(block_filename, 'rb', ...
0
votes
1answer
23 views

How many nodes would one typically check to determine the longest chain?

Before posting a solved block to the longest chain, how many nodes would one need to check before making sure that the longest chain was found?
1
vote
1answer
255 views

how to validate testnet and mainnet bitcoin address via online api or offline for Android App?

I would like to know web api provider to validate Mainnet & Testet3 Bitcoin Address. How to validate a Bitcoin address is a real one? Validate bitcoin address from android application Gone ...
2
votes
2answers
130 views

Any idea how to download a small part of the chain for testing purposes?

I am experimenting with Python and Rust libraries on my laptop. I don't actually want to get a node going on it and download the full chain; I just need some blocks to play with. I want to keep my ...
0
votes
1answer
28 views

How to protect the latest block in block chain be tampered?

We know for each block in block chain, it has the previous block header hash which make the block be tampered become difficult. If the block is tampered, then all blocks after this tampered block need ...
1
vote
1answer
69 views

Does P2SH unlocking script only consist of operants?

I have a question about the P2SH unlocking script. Can I put common operants and operators in the P2SH unlocking script? And if yes, how can I create such script? e.g. unlocing script: <sig1> &...
1
vote
2answers
53 views

How much data does it take to prove a given transaction exists on the blockchain?

As I understand the SVP protocol, a client can be reasonably certain that a transaction has been accepted on the blockchain if they know it is a member of a certain block, via the Merkle path, and a ...
0
votes
2answers
46 views

Can you explain to me how this transaction work?

I was looking at bitcoin rich list and found binance cold wallet For this transaction in particular https://www.blockchain.com/btc/tx/afb6523e4f5f060a076dcc2f8e5eb7a1aa58a3831456c62da946e2b5a41c24f0 ...
1
vote
1answer
39 views

How come Merkle tree is more efficient when tree branches are not stored in blockchain?

Suppose we have 8 transactions in a block X as follows and we know every node's hash value of the whole Merkle tree (that is, including intermediary nodes such as 45). Then if someone claims ...
0
votes
2answers
87 views

How to convert Satoshi to bitcoin? [duplicate]

hi people just i am join on this site.can anyone Help by telling me how to convert Satoshi into bitcoin?
1
vote
1answer
205 views

January 19th, 2038: RIP Unix Timestamps

Is there a plan in place for when the inevitable 32-bit overflow of Unix timestamps occurs? How much will this impact existing blocks that are timestamped with Unix Epoch times?
1
vote
2answers
146 views

How to display a list of incoming bitcoin Transaction history in my own wallet?

I have gone through various references including How to get a history of incoming and outgoing transactions for a certain address? Fetch list of transaction where i have received the bitcoin? I am ...
0
votes
1answer
184 views

how to get block information using node js

I have used bitcoin-core package in node js to get the information about the block detail using rpc command. For example: var Client = require('bitcoin-core'); const client = new Client({ headers:'...
1
vote
1answer
57 views

Can a live feed of blockchain transactions be obtained from using bitcoin core wallet?

I am interested in both obtaining the entire blockchain transaction history data (for bitcoin) and a live feed of transactions for a data science project. BlockChain.com has a very useful websocket ...
0
votes
2answers
96 views

How does blockchain technology handle the actual transaction data?

My understanding of how a transaction is secured in blockchain, especially in bitcoin, is that the output of transaction data is locked to the recipient's address (a shorter version of his public key)....
1
vote
2answers
47 views

How to confirm that given bitcoin address is generated by given public key?

I have 10s of private and public keys associated with 10s of different addresses. Now I have a test-net btc address "mfoxBS2TpoiUWrEV3sZopoEB6Pi2d7TE9N". What operations can I perform to find the ...
1
vote
1answer
21 views

Log information from the Ardor installer

I'm running into problems when trying to install Ardor. How can I configure the Ardor installer to log diagnostic information?
3
votes
3answers
561 views

Lost my Bitcoin wallet and have only 11 out of 12 mnemonic seed phrase words. How can I get my Bitcoins?

I am new to the whole Bitcoin thing, and I am having my first attempt almost going sour. I lost where I created my wallet. I have my Bitcoin address and only 11 of my mnemonic seed phrase words (of 12)...
1
vote
1answer
160 views

Balance zero after recovering wallet from seed-phrase

I recently got help my some experts on how i can recover my wallet using my private key, so i went ahead and downloaded brd wallet and block chain, then proceeded to recover wallet in the first and ...
0
votes
2answers
35 views

Who gives the block to the miner [duplicate]

Im still making my way into the block-chain world. I have been reading a lot. I want to know who gives a block to the miners?, then they compete to get the challenge right, whoever gets the ...
1
vote
0answers
15 views

Btc unconfirmed in recievers block chain wallet from last 9 days [duplicate]

I sent btc to the address on 27 th august 1PnNad5w5LDFuUudVMnrb7tAVP4U7jUHyr But in his blockchain wallet it showing still pending. What to do now.suggest me please txid ...
0
votes
1answer
19 views

In the case, bitcoin transactions are becoming less frequent, will the blockchain become unsafe?

The security of the blockchain relies in the fact that new blocks are added faster than any attacker guy can add them (as long as <51%) In case the frequency of the bitcoin transactions becomes ...
1
vote
1answer
29 views

Does all miners in mining pool increase the nonce variable one by one starting from zero?

Let us consider we have n miners in our mining pool. Now the manager of the pool verified the transactions and packed into a block to be mined. Then it passed the block to all n miners in the pool. ...
0
votes
1answer
25 views

How to determine what's mine?

I for example own 10 BTC does that mean, in some Blocks in the valid part of the blockchain is written, that I received at some point in time a certain amount of BTC? How do I prove that the ...
0
votes
1answer
24 views

Bitcoin and Merkle Tree - is in Bitcoin the Merkle Tree actually a List (which of course is a special form of a tree)?

When I get it right, each block in Bitcoins block chain contains a prev hash and a new block hash that includes this prev hash. So the genesis block only has itself and from there on each hash of the ...
1
vote
0answers
17 views

I own a Blockchain wallet and wishest put mneyon it from my visa debt card how do I do that [duplicate]

I own a blockchain wallet how do I fund it using my credit card
0
votes
2answers
73 views

blockchain official documentation

I am developing a system of administrative management. The project is migrating from PHP to C ++. With the new requirements we want to work with blockchain. But when looking for more about it, ...
0
votes
1answer
66 views

Access funds on legacy address related to segwit address from which I have private key

The situation Hello. Our company running BTC pool. We've been mining BTC for a while and used segwit address 32Z3eXSPgxcHj2fnQy8d6dg66eVtZfxrBM as pool adress. But when we finally found a first ...
0
votes
0answers
87 views

Bitcoin/PIVX JSON-RPC and CURL just returns Unauthorized

No matter what I try, I cannot get a request to PIVX wallet / Blockchain Api. It works 100% in curl from CMD. curl --user user:pass --data-binary "{\"jsonrpc\": \"1.0\", \"id\": \"curltest\", \"...
0
votes
1answer
38 views

Can Bitcoin Tech be Used to Protect Journalists [closed]

Over eight Nigerian journalists are currently in police detention because they published investigative news stories that didn't sit well with the government of the day. How can the bitcoin ...
0
votes
2answers
81 views

Calculate the difficulty of Bitcoin network

Which variable among the components of the block header is computed (or rather obtained) to achieve the difficulty posed by the bitcoin network? Nonce or Previous block hash?
0
votes
1answer
25 views

Statement: for an attacker to change history, they must solve computational puzzles at a faster rate than the rest of the participants combined

I'm new to cryptocurrency and blockchain. I just started reading the textbook Bitcoin and Cryptocurrency Technologies by Narayananm, Bonneau, Felten, Miller and Goldfeder. The statement in the title ...
0
votes
3answers
68 views

Is blockchain always “public”?

Is the following definition of blockchain by its wikipwdia page correct? Where it is mentioned: A blockchain is a decentralized, distributed and public digital ledger ... Cannot we have a ...
1
vote
0answers
27 views

Exchange development good practices

Is there any guide or good practice rules to follow when developing a service that uses the Bitcoin and other cryptocurrencies protocols? For instance, how is the best way to know if a user deposited ...
0
votes
2answers
47 views

What is the main difference between “light/thin client” and “client” in sense of “functionality” and “capability”?

What is the main difference between "light/thin client" and "client" in sense of "functionality and capability" ? I mean, what can a client does that a light/thin client cannot ? (ex. sending ...
0
votes
1answer
24 views

Help me resolve few queries about bitcoin network ( regarding validation, mining and state of transactions…)

Q1. Suppose I make a transaction from node A to node B, it is gets validated by the nodes in the network, A new block hasn’t been mined yet, in the meantime miner is stashing up the transactions Miner ...
0
votes
0answers
25 views

What kind of micro processor / micro controller can run Blockchain light client?

Is there any kind of micro-processor / micro-controller that can run Blockchain light client? An example can be Samsung ARTIK: https://www.artik.io However, it's too big. Is there any other similar ...
0
votes
1answer
30 views

How to make data inside blockchain immutable [closed]

I want to do simple blockchain implementation on golang, i have mongodb database with user info (Name, cardID, etc.) i want to store several information inside blockchain, and to put it inside another ...
0
votes
1answer
19 views

bitcoin transfer without creating wallet

My question is about transferring bitcoin between two addresses without having a wallet. Here is my idea of transferring bitcoins in following way: Idea: I have my own Android Application. I am ...
2
votes
1answer
48 views

How many transactions per block on Ardor? Plans for scaling?

How many total transactions are there in each Ardor block? Out of the total transactions per block, how many are child chain transactions? What are the limits and what types of scaling solutions are ...
0
votes
0answers
10 views

What does “third party liquidity” mean in blockchain technology?

In this what paper, it's mentioned that one of the reasons to use blockchain technology for the energy trading is: Provide 3rd party liquidity. What does "third party liquidity" mean in blockchain ...
0
votes
1answer
35 views

“Centralized Relational Databases” vs. “Decentralized Blockchain ” : Which one is really more scalable?

There are many research papers on problem of scalability of blockchains: Just as an example : An Overview of Blockchain Technology: Architecture, Consensus, and Future Trends However, (usually by ...
0
votes
3answers
57 views

If I invest £2,000 in bitcoin and the price goes down, can I lose more than my investment. Could i Have to sell my house to pay back the losses?

If I invest in Bitcoin is it possible to lose more than my initial investment ? In other words if the price goes down substantially, to well below that of when I initially invested; is it possible ...
0
votes
0answers
99 views

how to avoid blockchain downloading in bitcoinj?

I have created a bitcoin wallet with bitcoinj. It works with transactions very concurrently but after downloading whole blockchain. There is any way to avoid this downloading or faster downloading of ...
0
votes
2answers
27 views

Why is mining an important part of a digital coin? [duplicate]

I have been playing with the blockchain lately and studying how Bitcoin works. I was wondering though, what is the functional reason for the mining process? I understand that you get a reward for ...
0
votes
2answers
34 views

Bitcoin: can transaction and its parent be in the same block [duplicate]

I'm trying to understand bitcoin transactions verification specified here. Item 10 states, that parent transaction (mentioned as input for current) should be searched not only in already confirmed ...
1
vote
1answer
67 views

How can you get a list of all addresses mentioned in the blockchain?

I'd like to parse the blockchain in order to produce a list of all addresses that are mentioned in the blockchain. I'd like to do this with a program, language agnostic.