ECIP 1091: Fork identifier (`forkid`) protocol fork list specification v2

Author	Mr. Meows D. Bits
Discussions-To	https://github.com/ethereumclassic/ECIPs/issues/294
Status	Active
Type	Standards Track
Category	ECBP
Created	2020-06-03

Abstract

EIP-2124 (forkid) and EIP-2364 (eth/64) propose discovery protocol modifications which depend on lists of fork values. In case these changes are adopted and implemented on Ethereum Classic networks, this ECIP defines canonical lists of forks numbers for inclusion in the generation and validation steps of these “ForkID” schemes.

• https://eips.ethereum.org/EIPS/eip-2124
• https://eips.ethereum.org/EIPS/eip-2364

This specification describes a set of forks which exclude TheDAO fork event block(s) from forkid calculations, as well as excluding all forthcoming blockNumber % 5000000 == 0 blocks that, according to the algorithmdescribed in ECIP-1017 and enabled on ETC Mainnet and some testnets, will see reduced block reward values.

Motivation

Specify parameters for forkid generation and validation, so that in the case nodes on Ethereum Classic networks implement eth/64, they can do so in a consistent way.

As documented in EIP-2364, implementation for eth/64 does not demand consensus nor require any fork for node or network implementation.

Notwithstanding, it would be good for Ethereum Classic networks and clients to be able to implement the protocol change, if they want, according to a standard specification. Failure for clients to agree on forkid implementation could result in difficulty discovering each other.

Specification

Generally

Don’t include TheDAO fork blocks (eg. 1920000 on Mainnet, 1885000 on Morden) as a forkid parameter as specified in EIP-2124.

Don’t include any blocks subsequent and incidental to consensus-facing calculations according to accepted and implemented algorithms, eg. ECIP-1017.

Applied

The following data points are valid at time of last edit.

Ethereum Classic Mainnet (ETC)

• Genesis Hash: 0xd4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3

• • Forks: 1150000,2500000,3000000,5000000,5900000,8772000,9573000,10500839

• Head Block Number

  FORK_HASH

  FORK_NEXT

  RLP Encoded (Hex)

• | — | — | — | — |

• head=0

  FORK_HASH=fc64ec04

  FORK_NEXT=1150000

  c984fc64ec0483118c30

• head=1149999

  FORK_HASH=fc64ec04

  FORK_NEXT=1150000

  c984fc64ec0483118c30

• head=1150000

  FORK_HASH=97c2c34c

  FORK_NEXT=2500000

  c98497c2c34c832625a0

• head=1150001

  FORK_HASH=97c2c34c

  FORK_NEXT=2500000

  c98497c2c34c832625a0

• head=2499999

  FORK_HASH=97c2c34c

  FORK_NEXT=2500000

  c98497c2c34c832625a0

• head=2500000

  FORK_HASH=db06803f

  FORK_NEXT=3000000

  c984db06803f832dc6c0

• head=2500001

  FORK_HASH=db06803f

  FORK_NEXT=3000000

  c984db06803f832dc6c0

• head=2999999

  FORK_HASH=db06803f

  FORK_NEXT=3000000

  c984db06803f832dc6c0

• head=3000000

  FORK_HASH=aff4bed4

  FORK_NEXT=5000000

  c984aff4bed4834c4b40

• head=3000001

  FORK_HASH=aff4bed4

  FORK_NEXT=5000000

  c984aff4bed4834c4b40

• head=4999999

  FORK_HASH=aff4bed4

  FORK_NEXT=5000000

  c984aff4bed4834c4b40

• head=5000000

  FORK_HASH=f79a63c0

  FORK_NEXT=5900000

  c984f79a63c0835a06e0

• head=5000001

  FORK_HASH=f79a63c0

  FORK_NEXT=5900000

  c984f79a63c0835a06e0

• head=5899999

  FORK_HASH=f79a63c0

  FORK_NEXT=5900000

  c984f79a63c0835a06e0

• head=5900000

  FORK_HASH=744899d6

  FORK_NEXT=8772000

  c984744899d68385d9a0

• head=5900001

  FORK_HASH=744899d6

  FORK_NEXT=8772000

  c984744899d68385d9a0

• head=8771999

  FORK_HASH=744899d6

  FORK_NEXT=8772000

  c984744899d68385d9a0

• head=8772000

  FORK_HASH=518b59c6

  FORK_NEXT=9573000

  c984518b59c683921288

• head=8772001

  FORK_HASH=518b59c6

  FORK_NEXT=9573000

  c984518b59c683921288

• head=9572999

  FORK_HASH=518b59c6

  FORK_NEXT=9573000

  c984518b59c683921288

• head=9573000

  FORK_HASH=7ba22882

  FORK_NEXT=10500839

  c9847ba2288283a03ae7

• head=9573001

  FORK_HASH=7ba22882

  FORK_NEXT=10500839

  c9847ba2288283a03ae7

• head=10500838

  FORK_HASH=7ba22882

  FORK_NEXT=10500839

  c9847ba2288283a03ae7

• head=10500839

  FORK_HASH=9007bfcc

  FORK_NEXT=0

  c6849007bfcc80

• | head=10500840 | FORK_HASH=9007bfcc | FORK_NEXT=0 | c6849007bfcc80 |

  -

• Kotti

  -

• • Genesis Hash: 0x14c2283285a88fe5fce9bf5c573ab03d6616695d717b12a127188bcacfc743c4

• • Forks: 716617,1705549,2200013

• Head Block Number

  FORK_HASH

  FORK_NEXT

  RLP Encoded (Hex)

• | — | — | — | — |

• head=0

  FORK_HASH=0550152e

  FORK_NEXT=716617

  c9840550152e830aef49

• head=716616

  FORK_HASH=0550152e

  FORK_NEXT=716617

  c9840550152e830aef49

• head=716617

  FORK_HASH=a3270822

  FORK_NEXT=1705549

  c984a3270822831a064d

• head=716618

  FORK_HASH=a3270822

  FORK_NEXT=1705549

  c984a3270822831a064d

• head=1705548

  FORK_HASH=a3270822

  FORK_NEXT=1705549

  c984a3270822831a064d

• head=1705549

  FORK_HASH=8f3698e0

  FORK_NEXT=2200013

  c9848f3698e0832191cd

• head=1705550

  FORK_HASH=8f3698e0

  FORK_NEXT=2200013

  c9848f3698e0832191cd

• head=2200012

  FORK_HASH=8f3698e0

  FORK_NEXT=2200013

  c9848f3698e0832191cd

• head=2200013

  FORK_HASH=6f402821

  FORK_NEXT=0

  c6846f40282180

• | head=2200014 | FORK_HASH=6f402821 | FORK_NEXT=0 | c6846f40282180 |

  -

• Mordor

  -

• • Genesis Hash: 0xa68ebde7932eccb177d38d55dcc6461a019dd795a681e59b5a3e4f3a7259a3f1

• • Forks: 301243,999983

• Head Block Number

  FORK_HASH

  FORK_NEXT

  RLP Encoded (Hex)

• | — | — | — | — |

• head=0

  FORK_HASH=175782aa

  FORK_NEXT=301243

  c984175782aa830498bb

• head=301242

  FORK_HASH=175782aa

  FORK_NEXT=301243

  c984175782aa830498bb

• head=301243

  FORK_HASH=604f6ee1

  FORK_NEXT=999983

  c984604f6ee1830f422f

• head=301244

  FORK_HASH=604f6ee1

  FORK_NEXT=999983

  c984604f6ee1830f422f

• head=999982

  FORK_HASH=604f6ee1

  FORK_NEXT=999983

  c984604f6ee1830f422f

• head=999983

  FORK_HASH=f42f5539

  FORK_NEXT=0

  c684f42f553980

• | head=999984 | FORK_HASH=f42f5539 | FORK_NEXT=0 | c684f42f553980 |

  -

• Morden

  -

• • Genesis Hash: 0x0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303

• • Forks: 494000,1783000,1915000,2000000,2300000,4729274,5000381

• Head Block Number

  FORK_HASH

  FORK_NEXT

  RLP Encoded (Hex)

• | — | — | — | — |

• head=0

  FORK_HASH=417adbe7

  FORK_NEXT=494000

  c984417adbe7830789b0

• head=493999

  FORK_HASH=417adbe7

  FORK_NEXT=494000

  c984417adbe7830789b0

• head=494000

  FORK_HASH=aeb67dfb

  FORK_NEXT=1783000

  c984aeb67dfb831b34d8

• head=494001

  FORK_HASH=aeb67dfb

  FORK_NEXT=1783000

  c984aeb67dfb831b34d8

• head=1782999

  FORK_HASH=aeb67dfb

  FORK_NEXT=1783000

  c984aeb67dfb831b34d8

• head=1783000

  FORK_HASH=6a495281

  FORK_NEXT=1915000

  c9846a495281831d3878

• head=1783001

  FORK_HASH=6a495281

  FORK_NEXT=1915000

  c9846a495281831d3878

• head=1914999

  FORK_HASH=6a495281

  FORK_NEXT=1915000

  c9846a495281831d3878

• head=1915000

  FORK_HASH=e893e32d

  FORK_NEXT=2000000

  c984e893e32d831e8480

• head=1915001

  FORK_HASH=e893e32d

  FORK_NEXT=2000000

  c984e893e32d831e8480

• head=1999999

  FORK_HASH=e893e32d

  FORK_NEXT=2000000

  c984e893e32d831e8480

• head=2000000

  FORK_HASH=12a0ac82

  FORK_NEXT=2300000

  c98412a0ac8283231860

• head=2000001

  FORK_HASH=12a0ac82

  FORK_NEXT=2300000

  c98412a0ac8283231860

• head=2299999

  FORK_HASH=12a0ac82

  FORK_NEXT=2300000

  c98412a0ac8283231860

• head=2300000

  FORK_HASH=02a93060

  FORK_NEXT=4729274

  c98402a93060834829ba

• head=2300001

  FORK_HASH=02a93060

  FORK_NEXT=4729274

  c98402a93060834829ba

• head=4729273

  FORK_HASH=02a93060

  FORK_NEXT=4729274

  c98402a93060834829ba

• head=4729274

  FORK_HASH=4802d0c7

  FORK_NEXT=5000381

  c9844802d0c7834c4cbd

• head=4729275

  FORK_HASH=4802d0c7

  FORK_NEXT=5000381

  c9844802d0c7834c4cbd

• head=5000380

  FORK_HASH=4802d0c7

  FORK_NEXT=5000381

  c9844802d0c7834c4cbd

• head=5000381

  FORK_HASH=0b559b1d

  FORK_NEXT=0

  c6840b559b1d80

• | head=5000382 | FORK_HASH=0b559b1d | FORK_NEXT=0 | c6840b559b1d80 |

Rationale

The Ethereum Classic consensus protocol did not fork at block 1920000.

The Ethereum Classic disinflationary monetary policy is not considered a series of forks, it is the natural “stepping” behavior of a deterministic algorithm.

Implementation

Respective reference implementations for forkid generation are documented in EIP-2124 and EIP-2364.

At the time of last edit, client implementation tests may be found at:

• Core-Geth: https://github.com/etclabscore/core-geth/blob/master/core/forkid/forkid_test.go#L132, https://github.com/etclabscore/core-geth/blob/master/core/forkid/forkid_test.go#L322
• Multi-Geth: https://github.com/etclabscore/core-geth/blob/master/core/forkid/forkid_test.go#L132
• OpenEthereum: https://github.com/openethereum/openethereum/blob/master/ethcore/sync/src/chain/fork_filter.rs#L145

Change Log

• 2020-06-03
  • Modify Kotti eligible fork specs, removing blocks 2M and 5M. Prior specifications were generated using a faulty chain configuration, which wrongly included these blocks. Rel https://github.com/goerli/testnet/pull/71.
    • This modification is the first of its kind within this document, and is the sole modification against the superseded ECIP1082.