Can a miner steal another one's block?

6

1

Say we have two miners, Alice (an honest miner), and Eve (an evil miner).

My understanding is that when Alice mines a block she advertises it to the network, and once it's part of the longest block chain Alice earns mining reward + eventual transactions fees.

But could Eve steal this block (and the associated reward + fees)? When Alice publishes the block to the network, what happens if Eve republishes it as its own block? What if Eve is able to propagate the news that she mined the block herself in the network than Alice can?

I'm pretty sure Bitcoin has some mechanism around this issue and I'm curious to see how it works.

user2813687

Posted 2013-11-25T01:25:04.273

Reputation: 163

Answers

6

No.

The block that Alice mined includes the mining rewards going to Alice's address. If Eve alters the block data to output the rewards to her own receiving address, then the nonce (and other variable values, I think "extranonce" and timestamp) that Alice used to solve the block will almost certainly no longer solve the block.

Highly Irregular

Posted 2013-11-25T01:25:04.273

Reputation: 10 514

2So if I understand correctly, the miner's address is part of the hash it has to compute? (so if Eve was to tamper with it then the nonce wouldn't work anymore, right?) – user2813687 – 2013-11-25T10:55:04.620

@user2813687, yup, you've got it. – Highly Irregular – 2013-11-26T00:55:29.523

Eve either publishes Alice's block or she doesn't. If she publishes Alice's block, she's helping Alice get her block out. If she doesn't, then she has no effect on Alice. – David Schwartz – 2017-11-03T20:17:28.520

Asked: 2013-11-25T01:25:04.273

Viewed: 673 times

Active: 2016-02-12T16:29:46.877