WebRTC
What is it and Why should you care?
PyWeb-IL #90
By: Benny Daon
About Me
- Been to PyWeb-IL #1
- 30 years of coding in the shell
- Inspected a lot of packets
- Last year working on a WebRTC based terminal
The Itch:
Touching the terminal
and nothing happens
The Solution
Why WebRTC
- Real time
- Secure
- Rate Controlled
- Supported by all browsers
- Open source projects to start from:
- aiortc
- janus
- pion/webrtc
- ...
WebRTC History
- 2010 - Google buys GIPS
- 2011 - W3C publishes first draft
- 2014 - Google hangouts uses WebRTC
- 2017 - WebRTC 1.0 becomes a candidate recommendation
- 2021 - WebRTC 1.0 becomes a recommendation
WebRTC is an incomplete API
A bulky API covering a mesh
of network protocols while
leaving signaling to magic
The Browser Parts
By: Princiya
The Protocol Monster
By: Sean Dubois
Batteries Included
-
PeerConnection
- addTrack/onTrack
- createDataChannel/onDataChannel
- getStats
- ...
Interactive Connectivity Establishments
By: Andrew Prokov
Initiator Code
pc = new RTCPeerConnection({
iceServers: [ { urls: iceServers }],
certificates: myCert
})
pc.addTrack(track, stream...)
pc.createDataChannel('label')
pc.createOffer(offerOptions)
.then(desc => pc.setLocalDescription(desc))
pc.onicecandidate = signalMagicTracking State
pc.onconnectionstatechanged(e => {
switch(pc.connectionState) {
case "connected":
// The connection has become fully
// connected
case "disconnected":
case "failed":
// One or more transports has terminated
// unexpectedly or in an error
case "closed":
// The connection has been closed
})Accepting Offers
onOffer(offer) {
let sd = new RTCSessionDescription(offer)
pc.setRemoteDescription(sd)
}The story of RTOMax
RFC 4960: Stream Control Transmission Protocol
The computation and management of RTO in SCTP follow closely how TCP manages its retransmission timer.
RFC 4960: Stream Control Transmission Protocol
C7) A maximum value may be placed on RTO provided it is at least RTO.max seconds.