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MoreBC2

src/kernel/chainparams.cpp

CategoryDeveloper / Source AtlasStatusReviewed / Source-confirmed partialLast reviewed2026-09-12

Purpose

Section titled “Purpose”

src/kernel/chainparams.cpp defines BitcoinII chain-specific identity and consensus parameters. It is the primary release-pinned source for mainnet network identity, genesis data, deployment heights, proof-of-work parameters, checkpoints, address encodings, DNS seeds, minimum-chain-work, and assume-valid snapshots.

This page uses BitcoinII Core v31.1.0 as the current release baseline.

Mainnet identity

Section titled “Mainnet identity”

Current v31.1.0 mainnet source sets:

  • chain type: ChainType::MAIN;
  • message-start bytes: 0x42 0x49 0x49 0x21;
  • default P2P port: 8338;
  • prune-after height: 200000;
  • assumed blockchain size hint: 10;
  • assumed chain-state size hint: 10.

The September 11 Windows v31.1.0 node test directly observed the mainnet listener on 8338 and successful outbound peer discovery. That runtime result reinforces the chain-parameter value and also exposes why the generated example configuration’s inherited 8333 wording must not be treated as authoritative for current BC2 mainnet.

Genesis block

Section titled “Genesis block”
Field Value
Timestamp text BBC News 12/04/2024 French government collapses in no-confidence vote
Time 1734019071
Nonce 1597163478
Bits 0x1d00ffff
Version 1
Reward 50 * COIN
Genesis hash 0000000028f062b221c1a8a5cf0244b1627315f7aa5b775b931cfec46dc17ceb
Merkle root 80d1b4e9ca868f83b88b9301036205876072bdd3ded0ad4dc022e1f9266ddc49

Core consensus parameters

Section titled “Core consensus parameters”
Parameter Value
Subsidy halving interval 210000
BIP34 height 250
BIP65 height 260
BIP66 height 270
CSV height 280
SegWit height 290
Miner confirmation window 2016
Rule-change threshold 1815
Taproot deployment bit 2
Taproot minimum activation height 300

The 2016 miner-confirmation window is a deployment parameter. It must not be confused with the current post-activation difficulty-adjustment schedule.

BitcoinII-specific v31 activations

Section titled “BitcoinII-specific v31 activations”

Mainnet v31.1.0 sets:

Rule Height/value
Data restrictions 57750
ShockWave 57750
Replay protection 57750
Replay-protection fork/domain id 0x01324342

These three height-57750 changes are independent feature paths even though they share an activation height.

See Data restrictions, ShockWave, and Replay protection.

Proof-of-work parameters

Section titled “Proof-of-work parameters”
Parameter Value
powLimit 00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff
Historical/inherited target timespan 14 * 24 * 60 * 60 seconds
Target spacing 10 * 60 seconds
Allow minimum-difficulty blocks false
No retargeting false

The 14-day/2016-block values remain relevant to historical pre-ShockWave behavior and inherited helpers. Current mainnet difficulty at and after height 57750 is governed by ShockWave in src/pow.cpp.

Chain work and assume-valid

Section titled “Chain work and assume-valid”

These are release-specific snapshots and must always be labeled by source version.

For v31.1.0:

  • nMinimumChainWork = 0000000000000000000000000000000000000000000000959028194ff1139272
  • defaultAssumeValid = 00000000000000067e82c9cebc8b58e70f0be31908598d3240a4ecbaa527682e

The source comment associates the assume-valid hash with height 33000.

These values are startup/synchronization aids, not a replacement for BitcoinII’s accumulated-work chain-selection rule.

DNS seed

Section titled “DNS seed”

Current v31.1.0 mainnet source explicitly lists:

  • dnsseed.bitcoin-ii.org.

Older MoreBC2 material recorded bitcoinII.ddns.net. from an earlier source version. Treat that older seed as historical unless re-established by current release-pinned/project-controlled evidence.

Address encodings

Section titled “Address encodings”
Encoding Value
Base58 P2PKH prefix 0
Base58 P2SH prefix 5
Base58 secret-key prefix 128
Extended public key 04 88 B2 1E
Extended secret key 04 88 AD E4
Bech32 HRP bc

These Bitcoin-like encodings do not establish Bitcoin signing compatibility. From height 57750, BC2 signing/verification paths use the BC2 replay-protection domain where applicable.

Checkpoints

Section titled “Checkpoints”

The current v31.1.0 mainnet checkpoint table contains 23 entries and extends through:

  • height 57752;
  • hash 000000000000000013ceffe797280c57f75a5b9f1d9e70c3503584058c322576.

Checkpoint tables are release-specific snapshots, not dynamic finality rules. See Checkpoints.

Runtime boundary

Section titled “Runtime boundary”

The September 11 Windows runtime record directly confirmed a bounded subset of chain-parameter consequences, including:

  • chain main;
  • runtime version 310100 / /BitcoinII:31.1.0/;
  • protocol 70016;
  • P2P listener 8338;
  • successful outbound peer discovery;
  • current mainnet header acquisition.

It did not independently runtime-trigger the height-57750 replay/data-restriction/ShockWave activation transitions.

Section titled “Related pages”

Primary sources

Section titled “Primary sources”
  • v31.1.0/src/kernel/chainparams.cpp
  • v31.1.0/src/consensus/params.h
  • v31.1.0/src/pow.cpp
  • BitcoinII Core v31.1.0 release

Canonical tag: https://github.com/Bitcoin-II/BitcoinII-Core/tree/v31.1.0

Verification

Section titled “Verification”

Status: Reviewed / Source-confirmed partial
Primary evidence: BitcoinII Core v31.1.0 release-pinned chain parameters plus September 11 bounded Windows mainnet runtime evidence
Notes: Current mainnet identity, activation values, proof-of-work parameters, address encodings, DNS seed, chain snapshots, and the 23-entry checkpoint table are synchronized. Non-mainnet parameter sets and controlled activation-boundary vectors remain separate work.