SegWit BIPs
Segregated Witness related. 8 proposals.
- BIP 141 (SegWit): Segregated Witness (Consensus layer): Deployed. Defines Segregated Witness (SegWit), which moves signatures into a separate "witness" section of each transaction while remaining compatible with older nodes. This fixed transaction malleability,…
- BIP 142: Address Format for Segregated Witness: Closed. Proposed an address format for native SegWit outputs so wallets could send directly to the new transaction types. It was later replaced by the Bech32 address format (BIP 173), which became the…
- BIP 143 (SegWit signature hashing): Transaction Signature Verification for Version 0 Witness Program: Deployed. Changes how signatures are calculated for SegWit transactions so that verifying them no longer requires re-hashing the same data many times. It also makes the signature commit to the amount being…
- BIP 144: Segregated Witness (Peer Services): Deployed. Specifies the network messages nodes use to pass SegWit transactions and blocks to one another, including the separate signature data. It lets upgraded nodes share full witness data while older…
- BIP 145: getblocktemplate Updates for Segregated Witness: Deployed. Updates getblocktemplate, the interface miners and mining pools use to request a block to work on, so it supports SegWit. Without this, miners could not build blocks that include SegWit transactions…
- BIP 147 (NULLDUMMY): Dealing with dummy stack element malleability: Deployed. Fixes a quirk in Bitcoin's multisignature opcode, which consumes an extra unused value that anyone could modify without invalidating the transaction. Requiring that value to be empty removes one…
- BIP 148 (UASF): Mandatory activation of segwit deployment: Deployed. Proposed a user-activated soft fork (UASF), where nodes would reject blocks that did not signal support for SegWit after a set date. It was a way for users, rather than miners alone, to push SegWit…
- BIP 173 (Bech32): Base32 address format for native v0-16 witness outputs: Deployed. Introduces Bech32, an address format for native SegWit outputs, recognizable by addresses starting with "bc1". It uses only lowercase letters and numbers and a strong checksum that catches typing…