mpc/deployments/bridge

Lux Bridge MPC Integration

This directory contains the bridge compatibility layer that allows the Lux Bridge to use Lux MPC (Go implementation) instead of the legacy Rust MPC implementation.

Overview

The Lux Bridge currently uses KZen's multi-party-ecdsa Rust library for threshold signatures. This integration provides a compatibility layer that allows the bridge to seamlessly migrate to Lux MPC, which uses Lux's threshold Go implementation.

Quick Start

1. Build and Start the Services

# Run the migration script
./migrate.sh

# Or manually:
docker-compose up -d

2. Update Bridge Configuration

In your bridge's mpc.ts file, update the MPC node endpoints:

const mpc_nodes = [
  "http://bridge-compat-0:6000",
  "http://bridge-compat-1:6000",
  "http://bridge-compat-2:6000"
]

3. Test the Integration

# Check if compatibility endpoints are responding
curl http://localhost:6000/
curl http://localhost:6001/
curl http://localhost:6002/

Architecture

┌─────────────┐     ┌──────────────────┐     ┌─────────────┐
│   Bridge    │────▶│ Compatibility    │────▶│  Lux MPC    │
│   (Node.js) │     │ Layer (Port 6000)│     │ (Port 8080) │
└─────────────┘     └──────────────────┘     └─────────────┘
                              │
                              ▼
                    ┌──────────────────┐
                    │   NATS + Consul  │
                    │ (Messaging + SD)  │
                    └──────────────────┘

Services

• lux-mpc-[0,1,2]: Core MPC nodes using threshold
• bridge-compat-[0,1,2]: Compatibility layers on port 6000
• nats: Message broker for MPC communication
• consul: Service discovery

Key Differences

Feature	Rust MPC (Current)	Lux MPC (New)
Protocol	GG18	CGG21
Storage	File-based	BadgerDB
Communication	Process spawning	NATS messaging
API	HTTP on port 6000	gRPC + HTTP

Migration Steps

1. Test in Parallel: Run both implementations side-by-side
2. Shadow Mode: Send requests to both, compare signatures
3. Canary Deployment: Route 10% traffic to new implementation
4. Full Migration: Switch all traffic to Lux MPC

Monitoring

# View logs
docker-compose logs -f bridge-compat-0

# Check MPC node health
curl http://localhost:8080/health

# Monitor NATS
curl http://localhost:8222/varz

Troubleshooting

Compatibility layer not responding

docker-compose restart bridge-compat-0

MPC node issues

# Check logs
docker-compose logs lux-mpc-0

# Restart node
docker-compose restart lux-mpc-0

Key generation needed

# Use lux-mpc-cli to trigger key generation
docker exec -it lux-mpc-0 lux-mpc-cli keygen

Security Considerations

1. Key Migration: Existing Rust keys need to be converted to threshold format
2. Signature Compatibility: Both implementations produce standard ECDSA signatures
3. Network Security: Ensure proper TLS configuration in production

Performance

Expected improvements with Lux MPC:

• 30% faster signature generation (CGG21 vs GG18)
• Better resource utilization (Go vs Rust process spawning)
• Improved monitoring and observability

Next Steps

1. Complete key migration tool implementation
2. Add comprehensive integration tests
3. Performance benchmarking
4. Security audit of the compatibility layer