LP-0011: Chain Types - L1/L2/L3 Specification

Abstract

This LP defines the three chain types supported by the Lux Network: L1 (sovereign chains with independent validator sets), L2 (chains validated by the primary network), and L3 (application-specific chains built on L2s). Each type offers different tradeoffs between sovereignty, security inheritance, and operational complexity.

Motivation

Lux Network supports a flexible chain architecture where developers can choose the appropriate level of sovereignty and security for their use case:

• Maximum sovereignty: Run your own validator set (L1)
• Shared security: Inherit primary network security (L2)
• Application-specific: Build on existing L2 infrastructure (L3)

This specification provides the canonical definitions and CLI tooling for each chain type.

Specification

Chain Type Definitions

L1: Sovereign Chain

A fully independent blockchain with its own validator set.

type: L1
name: "Sovereign Chain"
validators: independent
security: self-provided
consensus: configurable
examples:
  - Hanzo (AI compute chain)
  - Custom enterprise chains

Characteristics:

• Own validator set (minimum 5 validators recommended)
• Full control over consensus parameters
• Independent staking economics
• Custom VM support
• Cross-chain communication via Warp messaging

CLI Creation:

lux chain create mychain --type l1 --validators 5 --vm evm
lux chain deploy mychain --mainnet

Genesis Configuration:

{
  "chainType": "L1",
  "validatorSet": {
    "type": "independent",
    "minValidators": 5,
    "stakingToken": "MYTOKEN"
  },
  "consensus": {
    "engine": "snowman",
    "parameters": {
      "k": 20,
      "alpha": 15,
      "betaVirtuous": 15,
      "betaRogue": 20
    }
  }
}

L2: Primary Network Validated Chain

A chain validated by the Lux primary network validators.

type: L2
name: "Primary Network Chain"
validators: primary-network
security: inherited
consensus: shared
examples:
  - Zoo (conservation/AI chain)
  - Partner ecosystem chains

Characteristics:

• Validated by primary network (no separate validator set needed)
• Inherits primary network security
• Lower operational overhead
• Shared LUX staking economics
• Faster time-to-launch

CLI Creation:

lux chain create mychain --type l2 --vm evm
lux chain deploy mychain --mainnet

Genesis Configuration:

{
  "chainType": "L2",
  "validatorSet": {
    "type": "primary-network",
    "inheritSecurity": true
  },
  "consensus": {
    "engine": "snowman",
    "parameters": "inherit"
  }
}

L3: Application Chain

An application-specific chain built on top of an L2.

type: L3
name: "Application Chain"
validators: l2-inherited
security: l2-inherited
consensus: l2-inherited
examples:
  - Gaming chains on Zoo
  - DeFi chains on partner L2s

Characteristics:

• Built on existing L2 infrastructure
• Inherits L2 security and validation
• Application-specific customization
• Minimal operational overhead
• Fastest deployment path

CLI Creation:

lux chain create myapp --type l3 --parent zoo --vm evm
lux chain deploy myapp --mainnet

Genesis Configuration:

{
  "chainType": "L3",
  "parentChain": "zoo",
  "validatorSet": {
    "type": "l2-inherited",
    "parentChainId": "200200"
  }
}

Comparison Matrix

Feature	L1 (Sovereign)	L2 (Primary Network)	L3 (Application)
Validators	Own set	Primary network	Parent L2
Security	Self-provided	Inherited	Double-inherited
Staking	Custom token	LUX	Parent token
Consensus	Configurable	Shared	Inherited
Launch Time	Weeks	Days	Hours
Operational Cost	High	Medium	Low
Sovereignty	Maximum	Medium	Limited
Use Case	Enterprise, AI compute	Ecosystem partners	Applications

CLI Commands

Chain Creation

# Create L1 sovereign chain
lux chain create <name> --type l1 [--validators N] [--vm <vm>]

# Create L2 primary network chain
lux chain create <name> --type l2 [--vm <vm>]

# Create L3 application chain
lux chain create <name> --type l3 --parent <l2-name> [--vm <vm>]

Chain Deployment

# Deploy to mainnet
lux chain deploy <name> --mainnet

# Deploy to testnet
lux chain deploy <name> --testnet

# Deploy locally
lux chain deploy <name> --local

Chain Management

# List chains
lux chain list [--type l1|l2|l3]

# Get chain info
lux chain info <name>

# Upgrade chain
lux chain upgrade <name> --config <config.json>

Cross-Chain Communication

All chain types support Warp messaging for cross-chain communication:

// WarpMessage structure (same for all chain types)
type WarpMessage struct {
    SourceChainID      ids.ID
    DestinationChainID ids.ID
    Payload            []byte
    Signature          []byte // BLS aggregate signature
}

L1 → L2 Communication:

# Send message from L1 to L2
lux warp send --from hanzo --to zoo --payload "0x..."

L2 → L3 Communication:

# Send message from L2 to child L3
lux warp send --from zoo --to zoo-gaming --payload "0x..."

Security Considerations

L1 Security

• Requires sufficient validator diversity
• Minimum 5 validators recommended
• Staking economics must incentivize honest behavior
• Slashing conditions must be defined

L2 Security

• Inherits primary network's 80%+ Byzantine fault tolerance
• No additional staking requirements
• Security scales with primary network

L3 Security

• Depends on parent L2 security
• Should verify parent L2 has sufficient security
• May add application-level security measures

Rationale

The three-tier chain architecture provides flexibility for different use cases:

1. L1 for sovereignty: Projects requiring full control (AI compute, enterprise) can run independent validator sets
2. L2 for ecosystem: Partner projects can launch quickly with inherited security
3. L3 for applications: Rapid deployment of application-specific chains

Backwards Compatibility

This LP introduces new chain type classifications. Existing chains are classified as:

• C-Chain, X-Chain, P-Chain: Primary network (special status)
• Existing custom chains: L1 by default (can opt into L2 model)

Reference Implementation

• CLI: github.com/luxfi/cli/cmd/chaincmd
• Node: github.com/luxfi/node/vms/platformvm/blocks
• Genesis: github.com/luxfi/genesis/pkg/genesis

Copyright

Copyright and related rights waived via CC0.