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quiz vs the machine

Platinum1860

Networking

WebTransport Overview

How WebTransport exposes QUIC streams and datagrams to web apps.

6 min read · advanced · beat Platinum to climb

A Modern Client To Server Channel

WebTransport gives web apps a flexible link to a server built on HTTP3 and QUIC. It aims to combine the strengths of WebSockets and raw datagram transport in one well defined interface.

Two Ways To Send

WebTransport exposes both reliable and unreliable delivery, letting an app pick per message.

  • Streams are reliable and ordered, like a WebSocket message, and a session can open many of them.
  • Datagrams are unreliable and unordered, ideal for the newest game or media state where stale data is worthless.

Because it rides on QUIC, streams are independent, so loss on one does not stall another.

How It Improves On WebSockets

A WebSocket gives one ordered stream, so a single lost packet blocks everything. WebTransport offers many independent streams plus datagrams over a single connection.

  • Connection migration from QUIC keeps a session alive across networks.
  • The integrated handshake trims setup round trips.
  • An app can mix reliable control and lossy fast paths together.

Where It Fits

WebTransport suits cloud gaming, live media, and real time apps that need both a reliable channel and a fire and forget channel without juggling several connections.

Key idea

WebTransport rides on HTTP3 and QUIC to give web apps both independent reliable streams and unreliable datagrams over one connection, surpassing the single ordered stream of WebSockets.

Check yourself

Answer to earn rating on the learn ladder.

1. What does WebTransport build on?

2. How does WebTransport improve on a WebSocket?

3. When are WebTransport datagrams a good fit?