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Explain extra nonce and timestamp to exceed 32 bit nonce #414

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Andreas M. Antonopoulos 2018-02-03 19:11:27 -06:00
parent 5b035b14db
commit 801374b344
1 changed files with 4 additions and 2 deletions
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@ -702,9 +702,11 @@ The difficulty of mining is closely related to the cost of electricity and the e
=== Successfully Mining the Block
((("mining and consensus", "mining the block", "successful completion")))((("use cases", "mining for bitcoin", id="jingtentwo")))As we saw earlier, Jing's node has constructed a candidate block and prepared it for mining. Jing has several hardware mining rigs with application-specific integrated circuits, where hundreds of thousands of integrated circuits run the SHA256 algorithm in parallel at incredible speeds. Many of these specialized machines are connected to his mining node over USB or a local area network. Next, the mining node running on Jing's desktop transmits the block header to his mining hardware, which starts testing trillions of nonces per second.
((("mining and consensus", "mining the block", "successful completion")))((("use cases", "mining for bitcoin", id="jingtentwo")))As we saw earlier, Jing's node has constructed a candidate block and prepared it for mining. Jing has several hardware mining rigs with application-specific integrated circuits, where hundreds of thousands of integrated circuits run the SHA256 algorithm in parallel at incredible speeds. Many of these specialized machines are connected to his mining node over USB or a local area network. Next, the mining node running on Jing's desktop transmits the block header to his mining hardware, which starts testing trillions of nonces per second. Because the nonce is only 32 bits, after exhausting all the nonce possibilities (about 4 billion), the mining hardware changes the block header (adjusting the coinbase extra nonce space or timestamp) and resets the nonce counter, testing new combinations.
Almost 11 minutes after starting to mine block 277,316, one of the hardware mining machines finds a solution and sends it back to the mining node. When inserted into the block header, the nonce 924,591,752 produces a block hash of:
Almost 11 minutes after starting to mine block 277,316, one of the hardware mining machines finds a solution and sends it back to the mining node.
When inserted into the block header, the nonce 924,591,752 produces a block hash of:
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0000000000000001b6b9a13b095e96db41c4a928b97ef2d944a9b31b2cc7bdc4