Network Architecture

Arch Network operates as a distributed system with different types of nodes working together to provide secure and efficient program execution on Bitcoin. This document details the network's architecture and how different components interact.

Network Overview

flowchart TB
    subgraph Core["Core Components"]
        direction TB
        BN[Bitcoin Network]
        Boot[Bootnode]
    end

    subgraph Leader["Leader Node Services"]
        direction LR
        TC[Transaction\nCoordination]
        MS[MultiSig\nAggregation]
    end
    
    subgraph Validators["Validator Network"]
        direction TB
        V1[Validator 1]
        V2[Validator 2]
        V3[Validator 3]
        VN[Validator N]
    end

    BN --> LN[Leader Node]
    Boot --> LN
    
    LN --> TC
    LN --> MS
    
    LN --> V1
    LN --> V2
    LN --> V3
    LN --> VN

    %% Styling
    classDef core fill:#e1f5fe,stroke:#01579b
    classDef leader fill:#fff3e0,stroke:#e65100
    classDef validators fill:#f3e5f5,stroke:#4a148c
    
    class BN,Boot core
    class TC,MS leader
    class V1,V2,V3,VN validators

Node Types

1. Bootnode

The bootnode serves as the network's entry point, similar to DNS seeds in Bitcoin:

  • Handles initial network discovery
  • Maintains whitelist of valid validators
  • Coordinates peer connections
  • Manages network topology
flowchart LR
    subgraph Bootnode["Bootnode Services"]
        direction TB
        PR[Peer Registry]
        WL[Validator Whitelist]
    end

    NN[New Node]
    VN[Validator Network]

    %% Connections
    NN <--> PR
    PR <--> VN
    WL -.-> PR

    %% Styling
    classDef bootnode fill:#e1f5fe,stroke:#01579b
    classDef external fill:#f5f5f5,stroke:#333
    classDef connection stroke-width:2px
    
    class PR,WL bootnode
    class NN,VN external

Configuration:

cargo run -p bootnode -- \
    --network-mode localnet \
    --p2p-bind-port 19001 \
    --leader-peer-id "<LEADER_ID>" \
    --validator-whitelist "<VALIDATOR_IDS>"

2. Leader Node

The leader node coordinates transaction processing and Bitcoin integration:

flowchart TB
    %% Main Components
    BN[Bitcoin Network]
    LN[Leader Node]
    VN[Validator Network]
    PE[Program Execution]
    
    %% Leader Node Services
    subgraph Leader["Leader Node Services"]
        direction LR
        TC[Transaction\nCoordination]
        MS[Multi-sig\nAggregation]
    end
    
    %% Connections
    BN <--> LN
    LN --> Leader
    TC --> VN
    MS --> VN
    VN --> PE
    
    %% Styling
    classDef bitcoin fill:#f7931a,stroke:#c16c07,color:white
    classDef leader fill:#fff3e0,stroke:#e65100
    classDef validator fill:#f3e5f5,stroke:#4a148c
    classDef execution fill:#e8f5e9,stroke:#1b5e20
    
    class BN bitcoin
    class LN,TC,MS leader
    class VN validator
    class PE execution

Key responsibilities:

  • Transaction coordination
  • Multi-signature aggregation
  • Bitcoin transaction submission
  • Network state management

3. Validator Nodes

Validator nodes form the core of the network's computation and validation:

flowchart TB
    subgraph ValidatorNode["Validator Node"]
        direction TB
        
        subgraph Execution["Execution Layer"]
            direction LR
            VM["Arch VM\nExecution"]
            SV["State\nValidation"]
        end
        
        NP["Network Protocol"]
        P2P["P2P Network"]
        
        %% Connections within validator
        VM --> NP
        SV --> NP
        NP --> P2P
    end
    
    %% Styling
    classDef validator fill:#f3e5f5,stroke:#4a148c,stroke-width:2px
    classDef execution fill:#e8f5e9,stroke:#1b5e20,stroke-width:2px
    classDef network fill:#e3f2fd,stroke:#0d47a1,stroke-width:2px
    
    class ValidatorNode validator
    class VM,SV execution
    class NP,P2P network

Types:

  1. Full Validator

    • Participates in consensus
    • Executes programs
    • Maintains full state

  2. Lightweight Validator

    • Local development use
    • Single-node operation
    • Simulated environment

Network Communication

P2P Protocol

The network uses libp2p for peer-to-peer communication:

pub const ENABLED_PROTOCOLS: [&str; 2] = [
    ArchNetworkProtocol::STREAM_PROTOCOL,
    ArchNetworkProtocol::VALIDATOR_PROTOCOL,
];

// Protocol versions
pub const PROTOCOL_VERSION: &str = "/arch/1.0.0";
pub const VALIDATOR_VERSION: &str = "/arch/validator/1.0.0";

Message Types

  1. Network Messages

    pub enum NetworkMessage {
    Discovery(DiscoveryMessage),
    State(StateMessage),
    Transaction(TransactionMessage),
}

  2. ROAST Protocol Messages

    pub enum RoastMessage {
    KeyGeneration(KeyGenMessage),
    Signing(SigningMessage),
    Aggregation(AggregationMessage),
}

Network Modes

1. Devnet

  • Local development environment
  • Single validator setup
  • Simulated Bitcoin interactions
  • Fast block confirmation

2. Testnet

  • Test environment with multiple validators
  • Bitcoin testnet integration
  • Real network conditions
  • Test transaction processing

3. Mainnet

  • Production network
  • Full security model
  • Bitcoin mainnet integration
  • Live transaction processing

Security Model

1. Validator Selection

pub struct ValidatorInfo {
    pub peer_id: PeerId,
    pub pubkey: Pubkey,
    pub stake: u64,
}

pub struct ValidatorSet {
    pub validators: Vec<ValidatorInfo>,
    pub threshold: u32,
}

2. Transaction Security

  • Multi-signature validation using ROAST protocol
  • Threshold signing (t-of-n)
  • Bitcoin-based finality
  • Double-spend prevention

3. State Protection

pub struct StateUpdate {
    pub block_height: u64,
    pub state_root: Hash,
    pub bitcoin_height: u64,
    pub signatures: Vec<Signature>,
}

Monitoring and Telemetry

1. Node Metrics

pub struct NodeMetrics {
    pub peer_id: PeerId,
    pub network_mode: ArchNetworkMode,
    pub bitcoin_block_height: u64,
    pub arch_block_height: u64,
    pub peers_connected: u32,
    pub transactions_processed: u64,
    pub program_count: u32,
}

2. Network Health

pub struct NetworkHealth {
    pub validator_count: u32,
    pub active_validators: u32,
    pub network_tps: f64,
    pub average_block_time: Duration,
    pub fork_count: u32,
}

3. Monitoring Endpoints

  • /metrics - Prometheus metrics
  • /health - Node health check
  • /peers - Connected peers
  • /status - Network status

Best Practices

1. Node Operation

  • Secure key management
  • Regular state verification
  • Proper shutdown procedures
  • Log management

2. Network Participation

  • Maintain node availability
  • Monitor Bitcoin integration
  • Handle network upgrades
  • Backup critical data

3. Development Setup

  • Use lightweight validator for testing
  • Monitor resource usage
  • Handle network modes properly
  • Implement proper error handling