I am not sure where OP_number <push_some_data> fits in since it's not mentioned in the article I referenced at the start of my thread.
OP_number is any OP code that is followed by a number is is simply pushing an integer to the stack. anything except negative one is used in SegWit outputs that is OP_0, OP_1, OP_2,.... OP_16.
here are two examples:
0014ecd2c537b2222dc367110450e2526beef3f2d110
OP_0 <ecd2c537b2222dc367110450e2526beef3f2d110>
52207713dd0580bec75aa5e74f53b9f34657c4af0cd9bcedbae7cfd062afb3d16b15
OP_2 <7713dd0580bec75aa5e74f53b9f34657c4af0cd9bcedbae7cfd062afb3d16b15>
currently only version 0 (OP_0) is defined.
But I think this may be used to acquire the actual Witness data that is stored beyond the regular limits of a Non-Segwit Block?
if we see this pubkey script is being spent then it signals the mandatory existence of witness in that transaction and some other rules such as signature script being empty.
The Segwit Miners made scriptPubKey: Empty in the coinbase transaction.
no, an empty pubkey script means nothing special. a SegWit node verifies all transactions including those that have witnesses and constructs the block and its coinbase transaction as before with 2 additional steps:
- add a single witness reserved value in coinbase witness
- add the witness commitment as a new pubkey script using OP_Return
ax explained in BIP-141
So scriptPubKey: Empty indicates that this is a Segwit UTXO.
no, a pubkey script that is in the way i explained above (OP_0 to OP_16 followed by a single push of between 2 to 40 bytes) is indicating a SegWit UTXO.\
this is similar to P2SH softfork. a pubkey script that is OP_HASH160 <20 bytes> OP_EQUAL demands extra steps that only new nodes understand and old nodes (before P2SH upgrade) can not verify.
A non-Segwit node will ignore all UTXO where scriptPubKey: Empty but a Segwit node will know which Bitcoin Address this UTXO belongs to.
no. nodes don't ignore anything and they must know which UTXO they belong to. keep in mind UTXO is not fetched by the script but by using the hash and index inside tx_in outpoint. the old nodes don't see the witness.