Byzantium Hard Fork changes

Contents

• What changes are included in the Byzantium hard fork?

What changes are included in the Byzantium hard fork?

The following upgrades are included:

• Addition of ‘REVERT’ opcode, which permits error handling without consuming all gas (EIP 140)
• Transaction receipts now include a status field to indicate success or failure EIP 658)
• Elliptic curve addition and scalar multiplication on alt_bn128 (EIP 196) and pairing checks (EIP 197), permitting ZK-Snarks and other cryptographic mathemagic™
• Support for big integer modular exponentiation (EIP 198), enabling RSA signature verification and other cryptographic applications
• Support for variable length return values (EIP 211)
• Addition of the ‘STATICCALL’ opcode, permitting non-state-changing calls to other contracts (EIP 214)
• Changes to the difficulty adjustment formula to take uncles into account (EIP 100)
• Delay of the ice age / difficulty bomb by 1 year, and reduction of block reward from 5 to 3 ether (EIP 649)

Source: verbatim extract from this Ethereum blog post.