Switchy P2P

P2P communication abstraction system - enables direct device-to-device connections.

Features

Core Abstractions

• Trait-based P2P System: Generic abstractions over different P2P implementations
  • P2PSystem - Core system interface for connections and discovery
  • P2PConnection - Reliable message streaming between peers
  • P2PNodeId - 256-bit node identifiers with deterministic/random generation

Network Simulator

The package includes a complete P2P network simulator with realistic network conditions:

• Topology Simulation: Graph-based network with configurable links and nodes
• Network Conditions: Configurable latency, packet loss, and bandwidth limits
• Discovery System: DNS-like peer discovery with name registration
• Network Partitions: Support for simulating and healing network splits
• Async Message Passing: FIFO-ordered message delivery with realistic delays
• Environment Configuration: Tunable parameters via environment variables:
  • SIMULATOR_DEFAULT_LATENCY_MS (default: 50ms)
  • SIMULATOR_DEFAULT_PACKET_LOSS (default: 1%)
  • SIMULATOR_DISCOVERY_DELAY_MS (default: 100ms)
  • SIMULATOR_CONNECTION_TIMEOUT_SECS (default: 30s)
  • SIMULATOR_MAX_MESSAGE_SIZE (default: 1MB)

Usage Example

use switchy_p2p::simulator::SimulatorP2P;

// Create a P2P node with deterministic ID for testing
let node = SimulatorP2P::with_seed("alice");
let node_id = node.local_node_id().clone();

println!("Node ID: {}", node_id.fmt_short());

The simulator provides methods for peer discovery and connection:

• register_peer(name, node_id) - Register a name for discovery
• discover(name) - Look up a node ID by name
• connect(node_id) - Connect to a peer by node ID
• connect_by_name(name) - Discover and connect in one step

Connections support send() and recv() for async message passing.

Cargo Features

• default = ["simulator"] - Enables the network simulator
• simulator - Network simulation implementation
• fail-on-warnings - Treat warnings as errors (CI use)

Planned:

• iroh - Integration with Iroh for production P2P networking
• test-utils - Testing utilities and property-based tests

Dependencies

• switchy_random - Deterministic and random number generation
• switchy_async - Async runtime utilities (sync, time, tokio)
• async-trait - Async trait support
• thiserror - Error type definitions

Architecture

Module Structure

• types - Core error types (P2PError, P2PResult)
• traits - Generic P2P abstractions (P2PSystem, P2PConnection, P2PNodeId)
• simulator - Complete network simulation implementation

Future Roadmap

Planned features:

• Iroh integration for production use with real NAT traversal
• Connection listener support (P2PListener trait)
• Property-based testing with proptest
• Advanced routing algorithms beyond BFS
• Bandwidth throttling simulation

License

Licensed under the same terms as the parent project.