gap-protocol

Group Audio Protocol — audio sub-protocol of the Group Protocol Stack.

GAP carries Opus media frames on top of the GBP base layer with per-source replay protection and epoch-bound key material.

Profile

• Opus at 48 kHz REQUIRED.
• 20 ms packetisation RECOMMENDED.
• FEC RECOMMENDED.
• Reliable delivery NOT RECOMMENDED (use the O flag profile only).

What this crate provides

• GapPayload — the audio frame envelope; can be encoded as CBOR, Protobuf, or FlatBuffers (selected by PayloadCodec). Using PayloadCodec::FlatBuffers (pf=2) minimises decode latency for real-time audio paths.
• GapClient — stateful client that maintains a per-source rtp_sequence window and validates key_phase against the current group epoch; accepts any PayloadCodec echoed from the payload_received event.

License

Licensed under Apache License, Version 2.0.