ethereum.forks.byzantium
The Byzantium fork (EIP-609) reduces the mining rewards, delays the difficulty bomb, enables contracts to make non-state-changing calls to other contracts, and adds cryptographic primitives for layer 2 scaling.
Changes
EIP-100: Change difficulty adjustment to target mean block time including uncles
EIP-197: Precompiled contracts for optimal ate pairing check on the elliptic curve alt_bn128
EIP-198: Precompiled contract for bigint modular exponentiation
Upgrade Schedule
| Network | Block | Expected Date | Fork Hash |
| Mainnet | 4,370,000 | October 16, 2017 | 0xa00bc324 |
Releases
FORK_CRITERIA
| 50 | FORK_CRITERIA = ByBlockNumber(4370000) |
|---|
ethereum.forks.constantinople
The Constantinople fork reduces mining rewards, delays the difficulty bomb, and introduces new EVM instructions for logical shifts, counterfactual contract deployment, and computing bytecode hashes.
Note that, on certain testnets, this fork is divided in two: Constantinople followed by Petersburg. On these testnets, Constantinople contains an additional change, EIP-1283, which was reverted in Petersburg. Because EIP-1283 was never present on mainnet, this specification omits the whole awkward situation and presents only a single fork without EIP-1283.
Changes
Upgrade Schedule
| Network | Block | Expected Date | Fork Hash |
| Mainnet | 7,280,000 | February 28, 2019 | 0x668db0af |
Releases
[Parity 2.2.10-stable][p]
FORK_CRITERIA
| 51 | FORK_CRITERIA = ByBlockNumber(7280000) |
|---|