moq-rs

An implementation of the Media over QUIC Transport (MoQT) protocol for live media delivery over QUIC, as specified by the IETF MoQ working group.

This codebase was originally created by Luke Curley (@kixelated). Mike English (@englishm) contributed to early design and has maintained this IETF-aligned fork. The project is now maintained by Cloudflare. The implementation targets draft-ietf-moq-transport-18.

Protocol Support

This checkout targets draft-18 of the MoQT specification. Raw QUIC uses the moqt-18 ALPN; WebTransport uses HTTP/3 with moqt-18 application-protocol negotiation. Both peers must support the same draft. The DraftVersion enum also names later drafts, but this implementation enables only draft-18.

Until draft-18-dev merges into main, build draft-18 clients and relays from the same draft-18-dev revision. Package versions and crates.io documentation still reflect the published release baseline; they do not identify the wire draft of this checkout. For draft-07 compatibility, see the draft-ietf-moq-transport-07 branch.

What's Included

This repository provides:

• moq-transport: A MoQT protocol library
• moq-relay-ietf: A relay server with subscription deduplication and fan-out
• Sample clients: An fMP4 publisher (moq-pub) and a demonstration clock application (moq-clock-ietf)

Protocol Feature Support

Supported:

• SETUP
• PUBLISH_NAMESPACE
• SUBSCRIBE
• SUBSCRIBE_NAMESPACE
• SUBSCRIBE_TRACKS and TRACK_STATUS
• PUBLISH / REQUEST_OK / PUBLISH_DONE (publisher-initiated tracks)
• Dynamic groups: DYNAMIC_GROUPS advertisement and NEW_GROUP_REQUEST feedback, including subscription REQUEST_UPDATE for that parameter
• FETCH, standalone and joining (the relay forwards it to the track's origin)
• WebTransport and raw QUIC transport layers
• Both stream ("subgroup") and datagram delivery modes

Not Supported:

• REQUEST_UPDATE parameters other than NEW_GROUP_REQUEST, including FORWARD (so a Joining FETCH can only join a subscription whose Forward State was set by SUBSCRIBE)
• Joining FETCH for a subscription created by PUBLISH (answered with NOT_SUPPORTED)

Interoperability

Check the draft supported by an interop endpoint before connecting. For a local draft-18 relay, use https://localhost:4443 after starting ./dev/relay. Hosts under relay.example in the crate READMEs are placeholders, not deployed endpoints.

As an implementation targeting the IETF specification, this codebase should be compatible with other implementations targeting the same draft version. See the moq-wg/moq-transport wiki for a list of other implementations.

For streaming format compatibility:

• video-dev/moq-js: A TypeScript player implementation compatible with moq-pub's fMP4 output. Check draft version compatibility when selecting branches.
• gst-moq-pub: A GStreamer publisher plugin built on moq-pub, also compatible with moq-js.

Components

This repository contains several crates:

• moq-transport: A media-agnostic library implementing the core MoQT protocol.
  • moq-native-ietf: QUIC and TLS utilities for native transport.
• moq-relay-ietf: A relay server that forwards content from publishers to subscribers, with caching and deduplication.
  • moq-api: An HTTP API server for origin discovery and relay coordination, backed by Redis.
• moq-pub: A publisher client that broadcasts fMP4 streams over MoQT.
  • moq-catalog: Catalog format handling.
  • moq-sub: A subscriber client for consuming MoQT streams.
• moq-clock-ietf: A simple time publisher/subscriber demonstrating non-media use cases.
• moq-cat-mint: A CLI that mints Common Access Tokens (CAT) for testing relays that require them.

Development

Typical development workflow:

1. Start a local relay in one terminal:

   ./dev/relay

2. Start a publisher in another terminal:

   ./dev/pub

   Add --tls-disable-verify if you prefer not to install local certificates.

3. Play the published broadcast in another terminal (requires ffplay):

   ./dev/sub

   Use the same NAME and URL environment variables for ./dev/pub and ./dev/sub when overriding the defaults. Browser players also need a branch compatible with draft-18; matching the media format alone is insufficient.

For a smoke test without a media player or ffmpeg, start ./dev/clock --publish and ./dev/clock in separate terminals. Add --tls-disable-verify to native clients only when testing with an untrusted local certificate.

See the dev helper scripts for more options and workflows.

Usage

For detailed usage information, see the README in each crate directory:

• moq-transport - Protocol library documentation
• moq-relay-ietf - Relay server configuration
• moq-pub - Publisher client usage

The moq-transport crate is also published on crates.io with API documentation. To read the API for this checkout, run cargo doc -p moq-transport --no-deps --open.

License

Licensed under either:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)