WebRTC DataChannel

Roland van Laar

Entrepreneur

Education IT / Consultancy

twitter: @rvanlaar github: rvanlaar roland@micite.net

Projects

FairlyValued

Slack GreetBot

Questions?

Javascript Level?

WebSockets?

Promises?

WebRTC: What it is

P2P: Browser to Browser

Audio

Video

DataChannel AKA P2P websockets

Usecase: Teacher and SmartBoard

Demo Time: WebSockets

WebRTC: What it's not

serverless: needs STUN/TURN

P2MultiPeer: unless using TURN

Easy to set up

Glossary

STUN: Session Traversal Utilities for NAT: external IP query

TURN: Traversals Using Relays around NAT: Media relay

ICE: Interactive Connectivity Establishment: IP-addresses

SDP: Session Description Protocol

Connection Establishment: Alice

create RTCPeerConnection object

create an offer (SDP session description) with RTCPeerConnection createOffer() method

calls setLocalDescription() offer

stringify the offer and pass it to Bob

Connection Establishment: Bob

call setRemoteDescription() with Alice's offer

call createAnswer(), and the success callback for this is passed a local session description: Bob's answer

Bob sets the answer as the local description by calling setLocalDescription()

Stringify the answer and pass it to Alice

Connection Establishment: Alice part 2

set Bob's answer with setRemoteDescription()

Was that everything?

Nope....

Demo Time: DataChannel

Thoughts

Spec is still in flux and getting better

Promise based

DataChannel setup changed

Hints

adapter.js for WebSockets

Usefull resources

• WebRTC Glossary
• WebRTC experiments
• WebRTC Infrastructure Explained
• Bistri: WebRTC-aaS