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Questions tagged [public-key]

A public key is the public half of the public/private keypair. Anyone can use a public key check that a signature is correct, but they can't generate the signature themselves with the public key.

A public key is the public half of a public/private ECDSA keypair. It is meant to be shared and without revealing the private key. Public keys can be used to verify a digital signature and encrypt data that can only be decrypted by the private key.

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What is a compressed Bitcoin key?

The standard Bitcoin client in version 0.6 apparently introduces compressed keys. What are they? Are there any drawbacks to using them? Any incompatibilities with older software? Reductions in cryptographic strength?
Thilo
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What is relation between scriptSig and scriptPubKey?

Scenario: A is sending 1 BTC to B. scriptSig appears in the Input Script. scriptSig = Here, public key is the Public Key of the sender, A. (this is the public key corresponding to his Bitcoin Address which has some unspent…
Neon Flash
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How are public & private keys in an address created?

I understand the high level concept I am more interested specific details. How is a private key generated. How exactly is public key generated, how is address generated from public key.
DeathAndTaxes
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Why does hashing public keys not actually provide any quantum resistance?

In the discussions about taproot, it was mentioned that outputs will include the public key directly instead of hashing them. It is stated that, currently, hashing does not really provide quantum resistance. Why is that?
Andrew Chow
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Is it possible to get the public key of a bitcoin address I do not have the private keys for with the standard client?

It is possible to get it from here: https://blockchain.info/de/q/pubkeyaddr https://blockchain.info/q Is it possible with the standard client? How? I am aware that the blockchain only contains the pubkey after a tx from that address.
kermit
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How are public and private keys related to the wallet?

I understand that all the Bitcoin protocol is based on an asymmetric cryptography. A user gets 2 keys (public and private). How do these keys connect to the Bitcoins? How are the keys are related to the wallet? How can I decide how many Bitcoins to…
Sean Black
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Why do you use Bitcoin addresses instead of public keys?

Why do you hash the public key twice? Are there security benefits to abstracting away from the public key? Is it because the address can represent multiple things? I'm missing something. Could you theoretically send bitcoins directly to the public…
ihtkwot
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What is a private key and a public key?

What exactly is a private key and public key in relation to Bitcoin? What are they, how are they used, and how does one find out what their private and public keys are?
Sam Weinberg
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Why does the length of a bitcoin key vary?

Why does the length of a bitcoin key vary? Why aren't they all the same length?
shoeless joe
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Does a wallet containing multiple addresses have a single private key?

Title says it all. Would one private key enable you to recover all the addresses in your wallet? Or does a wallet just contain a series of key-pairs?
Leftover Salad
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Why is it not possible to get the private key out of the public key?

From how I understand it, the equation for the public key is defined as so: K = k * G With K being the public key, k the private key and G the generator point. Is G a constant? (as far as I read, it is a constant.) If it is, how is it not…
Purple Gang
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All Bitcoin Public Keys with non-zero balance

I want to get a database or otherwise retrieve a set off all bitcoin public keys (not addresses) that have non zero balances. What would be the easiest way to do that? Is there an API that could do such thing? Do I have to download and prune the…
Benedikt Bünz
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Can private keys remain offline for their entire life?

I am new to Bitcoin and this question is based on 3 assumptions that may be incorrect. Assumption 1: If I understand correctly, the Bitcoin address is generated algorithmically independent of the network, so I should be able to create a public…
Usman Mutawakil
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What are the potential attacks against ECDSA that would be possible if we used raw public keys as addresses?

According to this answer about why addresses are hashes rather than public keys there are potential attacks that are possible if you have the public key rather than the address, what are these attacks? If one was writing a cryptocurrency would you…
Leah Cornelius
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How would one "Encrypt" a message using a Bitcoin *public key* and use its private key to decrypt it?

I have the following text string: This is a test message. Using my bitcoin public key (bitcoin address?), how can I encrypt this message? How would I decrypt the message using a bitcoin private key?
Patoshi パトシ
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