New answers tagged

2

Perhaps you're confused by the phrasing "the wallet", as it's only the receiver's wallet who needs to know the public key, and he has it, because he created the address in the first place. In what follows, I'm going to assume a standard 1... address (pay to pubkey hash). That's not the only type of address, but similar ressonings apply to every type of ...


1

I was under the impression that addresses are just a encoded Yes, addresses are encoded (base58 or base32) to help human readability. They include a checksum to ensure protection against errors in address transcription and entry. A bitcoin address can represent the owner of a private/ public key pair, or it can represent any other script that can be ...


0

There are different kinds of ouputs a transaction can pay to. For simplicity I'll explain it with a Pay-to-PubkeyHash (P2PKH) output as an example. I think this is what your question is based on. With a P2PKH output you are right. An address is just an encoded and hashed public key with a prefix. You can remove the prefix and reverse the encoding, but you ...


2

They are very different. If you look at their byte values, you will notice that they are different lengths and have different formats. In essence, public keys are identifiers and signatures are cryptographic proofs. A signature is produced by taking a private key and a message and performing a signature algorithm with those two pieces of data as inputs. ...


2

What i missed? You are hashing sigHash (ie. the already hashed message) with SHA1 and then recover public key using that result which will give you 03519e33c6b146628b4010ae2b56aa9127ae9b795c82df021979436296daf4ccea as the recovered public key (can't re-calculate the second one with my c# code)! I believe that this is the source code of the ...


1

I was told that the minimum number is 0. That is correct. 0x3400000000000000000000000000000000000000000000000000000000000000 is a valid x-coordinate on secp256k1. My understanding is that the answer is supposed to be like this: '0434' + hex(n) + y_value. I am not sure how to approach this That is also correct. However, you will have two y-coordinates. ...


1

Speaking of bitcoin (other cryptocurrencies may do things a bit differently but the principles will likely be similar) and simplifying slightly (i.e. not discussing stuff like segwit). For ECDSA a private key is simply a large (psuedo)-random number. Depending on the particular wallet implementation the private key may be generated and stored, or it may be ...


2

Public key cryptography has nothing to do with 51% attacks. The only thing a miner can do with >50% hash power is double spend bitcoins for which he controls the private key or censor transactions by not including them in the blocks he creates. He cannot spend bitcoins for which he doesn't control the private keys.


Top 50 recent answers are included