Genesis upgrade
Genesis is a major update to the BitcoinSV mining client which is used by the majority of miners on the BitcoinSV network.
The upgrade is seen as a return to the original Bitcoin protocol, and includes the removal of all limit based consensus rules, and their replacement with miner configurable settings that give node operators the autonomy needed to set their own limits as they determine are practical.
The full specification is available here.
A short summary of the specification is given here.
Genesis is scheduled to go into effect on or around the 4th of February 2019.
See also:
https://bitcoinsv.io/2020/01/15/changes-for-the-genesis-upgrade/
https://www.prnewswire.com/news-releases/bitcoin-svs-genesis-hard-fork-300989579.html
The four following areas of the protocol and specification contain the changes implemented by the Genesis upgrade.
Block Consensus Rules
These consensus rules apply to blocks that are produced after Genesis activation.
- Block Size - The size of a block in bytes of the serialized form of the block including the block header and all of the transactions confirmed by the block.
- Number of CheckSig Operations per MB of Block Space - The consensus rules that limits the number of checksig operations per megabyte of block space has been removed.
Transaction Consensus Rules
These consensus rules apply to transactions that are confirmed in blocks after Genesis activation.
- Maximum Transaction Size - The size of a transaction is the size in bytes of the serialized form of the transaction. The maximum size of a transaction is 1GB (1,000,000,000 bytes). This limitation is expected to be lifted in the future.
- Maximum Number of CheckSig Operations per Transaction
- nLockTime and nSequence - After Genesis activation, the functionality of the nLockTime field of a transaction and the nSequence fields of transaction inputs revert to their original purpose. The rules defined here only apply to transactions that are confirmed after Genesis activation.
Script Language Rules
Bitcoin Script is the programming language that is used to lock and unlock transaction outputs. This section contains changes to the Script Language Rules.
The rules defined here apply to locking and unlocking scripts for transaction outputs that are created after the Genesis activation. The previous rules apply to transaction outputs created prior to Genesis activation.
- P2SH sunset - The P2SH capability is being removed by the Genesis upgrade and the presence of a p2sh script template in an output will invalidate a transction.
- OP_RETURN functionality - the functionality of the OP_RETURN operation is being restored. OP_RETURN will cause termination of the script and the validity of the script is determined by the value of the top item on the stack.
Standard Local Policies
Policies are settings that are configured by software operators. These settings are generally required by software implementations. Policies control which transactions the software will propagate the P2P network are not Bitcoin Rules or Consensus Rules and are not used to determine the validity of blocks or the transactions confirmed by the block.
Standard Local Transaction Policies
- Maximum Acceptable Transaction Size Policy
- Transaction Evaluation Timeout
Standard Local Script Language Policies
- Numeric Value Length
- Stack Memory Usage
Standard Local P2P Network Policies
- Propagation of non-Standard Transactions