Architecture Overview

Core Components

Arch VM

The Arch Virtual Machine (VM) executes Solana-style SBF/sBPF programs, providing a secure and efficient environment for deterministic program execution.

Key features:

• Manages program execution
• Handles state transitions
• Ensures deterministic computation
• Provides syscalls for Bitcoin UTXO operations
• Supports compute budget management
• Handles program upgrades and migrations

Bitcoin Integration

Arch Network interacts directly with Bitcoin through:

• Native UTXO management via bitcoin-internal crate
• Transaction validation and synchronization
• Multi-signature coordination
• State commitment to Bitcoin
• Real-time Bitcoin network monitoring
• UTXO graph processing and rollback support

Distributed Key Generation (DKG)

The DKG system enables secure multi-signature operations:

• Threshold signature schemes (t-of-n)
• Peer-to-peer key generation
• Dynamic participant management
• Malicious participant detection
• Network message routing and validation

Validator Network

The validator network consists of multiple node types that work together:

Node Types

Core Programs

Arch Network includes several built-in programs that provide essential functionality:

APL Token Program

• Fungible token creation and management
• Multi-signature support
• Account freezing and thawing
• Supply management and minting
• Authority management and delegation

Associated Token Account (ATA)

• Automatic token account creation
• Rent-exempt account management
• Deterministic address derivation
• Account lifecycle management

Compute Budget Program

• Transaction compute unit management
• Fee calculation and optimization
• Resource allocation control
• Performance monitoring

System Program

• Account creation and management
• Ownership transfers
• Lamport management
• UTXO anchoring

Transaction Flow

Security Model

Arch Network implements a robust multi-layered security model that directly leverages Bitcoin's security guarantees:

1. UTXO Security

• Ownership Verification

  • Public key cryptography using secp256k1
  • BIP322 message signing for secure ownership proofs
  • Double-spend prevention through UTXO consumption tracking

• State Management

  • State anchoring to Bitcoin transactions
  • Atomic state transitions with rollback capability
  • Cross-validator state consistency checks
  • Real-time UTXO graph validation

2. Transaction Security

pub struct SecurityParams {
    pub min_confirmations: u32,    // Required Bitcoin confirmations
    pub signature_threshold: u32,   // Multi-sig threshold
    pub timelock_blocks: u32,      // Timelock requirement
    pub max_witness_size: usize,   // Maximum witness data size
    pub dkg_timeout: Duration,     // DKG operation timeout
    pub malicious_threshold: u32,  // Malicious participant threshold
}

• Multi-signature Validation
  • ROAST protocol for distributed signing
  • Threshold signature scheme (t-of-n)
  • Malicious signer detection and removal
  • Binding factor verification for signature shares
  • Dynamic participant management

3. Network Security

• Peer Validation

  • Authenticated peer discovery
  • Message integrity verification
  • Rate limiting and DoS protection
  • Network topology validation

• State Synchronization

  • Consensus-driven state updates
  • Rollback capability for invalid states
  • Cross-validator state verification
  • Real-time conflict resolution

Performance Characteristics

Scalability

• Horizontal Scaling: Add more validators for increased throughput
• Parallel Processing: Multiple transactions processed simultaneously
• Efficient Storage: Optimized data structures for fast access
• Network Optimization: Efficient peer-to-peer communication

Throughput

• High TPS: Optimized for high transaction throughput
• Low Latency: Fast transaction confirmation
• Batch Processing: Efficient handling of multiple operations
• Resource Management: Compute budget optimization

Reliability

• Fault Tolerance: Continues operation despite node failures
• Recovery: Automatic recovery from network partitions
• Audit Trail: Complete transaction history and state changes
• Monitoring: Real-time performance and health monitoring

Development Workflow

Local Development

# Start complete local environment
arch-cli orchestrate start --local "$(pwd)"

# Use configuration profiles for different environments
arch-cli config create-profile dev --bitcoin-node-endpoint http://127.0.0.1:18443

# Deploy and test programs
arch-cli deploy target/deploy/

Testing and Validation

• Unit Testing: Individual component testing
• Integration Testing: End-to-end workflow validation
• Network Testing: Multi-node network simulation
• Performance Testing: Throughput and latency measurement

Deployment

• Staged Rollouts: Gradual feature deployment
• Rollback Capability: Quick reversion to previous versions
• Monitoring: Real-time performance and error tracking
• Debugging: Comprehensive logging and error reporting