Universal Connectivity

Realtime highly decentralised chat app with extension protocol support.

🌐 Live Demo: https://dweb.link/ipfs/bafybeiesr6wwz5boxhw3fwn5pdj2bgccsikci2ssklwdp6lao23vfsafmm

Showcasing libp2p's superpowers in establishing ubiquitous peer-to-peer connectivity in modern programming languages (Go, Rust, TypeScript) and runtimes (Web, native binary).

On top of this strong foundation, it layers a GossipSub: A Secure PubSub Protocol for Unstructured Decentralised P2P Overlays. By analogy, an event broker with distributed brokering, or a distributed PubSub protocol.

This is the gossip event protocol that powers Filecoin and Post-Merge Ethereum.

Some of the cool and cutting-edge transport protocols used by this app are:

• WebTransport
• WebRTC
• WebRTC-direct
• QUIC
• TCP

Packages

Package	Description	WebTransport	WebRTC	WebRTC-direct	QUIC	TCP
js-peer	Browser Chat Peer in TypeScript	✅	✅	✅	❌	❌
node-js-peer	Node.js Chat Peer in TypeScript	✅	✅	✅	✅	✅
go-peer	Chat peer implemented in Go	✅	❌	✅	✅	✅
rust-peer	Chat peer implemented in Rust	❌	❌	✅	✅	✅
nim-peer	Chat peer implemented in Nim	❌	❌	❌	❌	✅

✅ - Protocol supported ❌ - Protocol not supported

• Uses the GossipSub PubSub protocol for decentralised messaging

UC Extension Protocol (UCEP)

The Universal Connectivity Extension Protocol enables peer-to-peer apps to discover and interact with extensions running on other peers. Apps can dynamically discover available functionality from connected peers and execute commands without knowing about extensions beforehand.

How it works

1. Discovery: Peers advertise extensions via libp2p identify protocol with custom protocol IDs: /uc/extension/{extensionId}/{version}
2. Manifest Exchange: Peers request extension manifests containing metadata, commands, and UI URLs
3. Command Execution: Execute commands on remote extensions via protobuf-encoded messages over direct streams
4. User Installation: Users can install extensions from peers and access their functionality through the chat interface

Demo Video

Watch the demo showing a collaborative spreadsheet extension in action

Reference Implementation

See the spreadsheet example for a complete implementation of UCEP. This example shows:

• Extension service setup with topology tracking
• Manifest and command request handling
• Integration with a Yjs collaborative spreadsheet
• Direct stream communication using pbStream

Build Your Own Extension

Any app can implement UCEP! Examples:

• Todo apps: Share and sync tasks across peers
• File sharing: Discover and request files from peers
• Games: Find and join multiplayer sessions
• Collaborative tools: Real-time document editing, whiteboards

The protocol is transport-agnostic and works over any libp2p connection (WebRTC, WebTransport, QUIC, TCP).

Connecting to a peer

There are two ways to connect to a peer:

• With a PeerID using peer routing (adds a step to resolve the multiaddr for the PeerID), using the IPFS/Libp2p DHT, e.g. 12D3KooWLMySi3eEWscUnKmMCYRSXL3obYJ4KNimpShJK6shUy2M
• With a multiaddr directly (skips the peer routing step), e.g. /ip4/127.0.0.1/udp/64434/webrtc/certhash/uEiA_tkndZQWf7jyFqgCiwH_CqsS7FTWFTb6Px8MPxxT9gQ/p2p/12D3KooWLMySi3eEWscUnKmMCYRSXL3obYJ4KNimpShJK6shUy2M

Using a multiaddr

Load the UI, and enter the multiaddr into the UI. Ensure that it includes the peerID, e.g./ip4/192.168.178.21/udp/61838/quic-v1/webtransport/certhash/uEiCQCALYac4V3LJ2ourLdauXOswIXpIuJ_JNT-8Wavmxyw/certhash/uEiCdYghq5FlXGkVONQXT07CteA16BDyMPI23-0GjA9Ej_w/p2p/12D3KooWF7ovRNBKPxERf6GtUbFdiqJsQviKUb7Z8a2Uuuo6MrDX

Getting started: Browser JS

1. Install dependencies

Run npm install:

cd js-peer
npm i

2. Start Next.js dev server

Start the dev server:

npm run dev

Getting started: Node.js

1. Install dependencies

cd node-js-peer
npm i

2. Start the app

npm start

Getting started: Rust

cd rust-peer
cargo run

To start the Rust Peer with an argument, you can use the following command:
cargo run -- --gossipsub-peer-discovery dev-dcontact._peer-discovery._p2p._pubsub

This will automatically connect you to the bootstrap nodes running on bootstrap.libp2p.io.

To explore more advanced configurations if you e.g. want to set up our own network, try:

cargo run -- --help

Getting started: Go

cd go-peer
go run .

Getting started: Nim

cd nim-peer
nimble build

# Wait for connections in tcp/9093
./nim_peer

# Connect to another node (e.g. in localhost tcp/9092)
./nim_peer --connect /ip4/127.0.0.1/tcp/9092/p2p/12D3KooSomePeerId