PeerConnectionTestSpecification.md

Overview

The purpose of the Peer Connection Test is verify that the WebRTC steps up to and including a DTLS handshake can be successfully completed between two peers: the Server Peer and the Client Peer.

View the Code

The descriptions in the following sections outline how the Server Peer and Client Peer work together. Often it can be easier to read the code. A number of implementations in different languages that can be reviewed:

• Python: aiortc Test Server
• Python: aiortc Test Client
• Go: Pion Test Server
• Go: Pion Test Client
• C#: SIPSorcery Test Server
• C#: SIPSorcery Test Client
• C++: libdatachannel Test Server
• C++: libdatachannel Test Client
• TypeScript: werift Test Server
• TypeScript: werift Test Client
• Rust: webrtc-rs Test Server
• Rust: webrtc-rs Test Client

Signaling

The single step signaling operation involved in the test is a HTTP POST request from the Client Peer to the Server Peer. The Client must send its SDP offer to the Server and the Server will respond with its SDP answer.

Note: Using this single-shot signaling approach means that at least one of the Client Peer or Server Peer must operate in non-trickle ICE mode and include their ICE candidates in the SDP. Ideally both peers should be configured to operate in non-trickle mode. This is a deliberate choice in order to reduce the signaling complexity.

Server Peer Operation

The required operation for a Server Peer is:

• Listen on TCP port 8080 for HTTP POST requests. The URL that the HTTP server must listen on for POST requests is:
  • http://*:8080/offer (if a wildcard IP address cannot be used any address that the client can reach is suitable).
• POST requests from the client will have a body that is a JSON encoded RTCSessionDescriptionInit object.
• When an SDP offer is received create a new Peer Connection and set the remote offer.
• Generate an SDP answer and return it as a JSON encoded RTCSessionDescriptionInit object in the HTTP POST response.
• Perform the Peer Connection initialisation.

Client Peer Operation

The required operation for a Client Peer is:

• Create a new Peer Connection and generate an SDP offer.
• Send the SDP offer as a JSON encoded RTCSessionDescriptionInit object to the Server Peer with an HTTP POST request to:
  • http://localhost:8080/offer (adjust the address if the server is not on localhost)
• The HTTP POST response will be an SDP answer as a JSON encoded RTCSessionDescriptionInit object.
• Set the remote offer on the Peer Connection.
• Perform the Peer Connection initialisation.
• If the DTLS handshake is successfully completed the client should Return 0. If the test fails or times out the client should Return 1. It's solely up to the Client Peer to decide if the test was successful or not.

In addition to the various implementations listed above a javascript application that functions as an Echo Test Client Peer is available here.