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How to create coinbase? How to use witness?

BIP141 adds a new rule called "witness commitment". The document says: "The commitment is recorded in a scriptPubKey of the coinbase transaction." I didn't quite understand what ...
Jack Green's user avatar
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Are all transactions, whether SegWit or non-SegWit, part of the commitment in a coinbase transaction?

A merkle root in a block header is a way to commit all transactions in that block. However, since it does not cover transaction witness data, another commitment needs to be made in a coinbase ...
LeaBit's user avatar
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Is the "witness commitment" introduced in bip-0141 optional?

In BIP-0141, it states: a new block rule is added which requires a commitment to the wtxid. the coinbase's input's witness must consist of a single 32-byte array for the witness reserved value. ...
Simon L's user avatar
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How do I calculate the witness commitment hash for a given block?

From my understanding, every SegWit enabled block has an added output script which is used as a place to store the "Witness commitment" specified in BIP 141. One issue I've stumbled upon was ...
Mason Ticehurst's user avatar
1 vote
1 answer
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Why is the bytestring 0xaa21a9ed used as the witness commitment header in SegWit?

As per BIP 141, the witness Merkle root hash is stored in a scriptPubkey field of a coinbase transaction output with a header consisting of the 4-byte string 0xaa21a9ed. What is the reasoning behind ...
sarva's user avatar
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2 answers
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SegWit witness commitment merkle root location

BIP 141 defines the commitment structure here What i am unsure about is the location of this data. I know it will be in scriptPubKey. Does this mean Coinbase tx will have more than one output? Also is ...
Albert S's user avatar
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2 votes
1 answer
759 views

What is the "witness reserved value" for BIP-141?

BIP-141 defines a witness reserved value as part of a flexible commitment structure: Double-SHA256(witness root hash|witness reserved value) The purpose is to support commitments (i.e., data ...
Rich Apodaca's user avatar
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4 votes
1 answer
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If a block contains no SegWit transactions, does a miner send an (empty) witness?

Also, would that block's Coinbase contain some kind of empty witness commitment?
pinhead's user avatar
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