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proposals refer to an array of hex-encoded short transaction IDs that represent proposed transactions within a block or its uncle blocks. A transaction proposal ID is the first 10 bytes of the transaction hash. In CKB, the transaction proposal ID must be proposed before a transaction can be committed to the blockchain.

  • A transaction is considered proposed if its proposal ID is listed in the proposals field of a block or an uncle of that block.
  • A transaction is considered committed once it appears in a block‚Äôs transactions field.
Lifecycle of proposals

Two protocol parameters, close and far, specify the closest and farthest on-chain distances between a transaction's proposal and commitment. A non-cellbase transaction commit in block c must have been proposed in block p, where

close <= c - p <= far

In CKB's Mainnet, close is 2 and far is 10. Thus:

2 <= c - p <= 10

As shown above, when a transaction is committed in Block 23, it should have been proposed in the tx_proposal_window between Block 13 and Block 21.