How exactly was the web consultation (video calls) set up?

To set up a web consultation with video calls, WebRTC is usually used — a technology that allows establishing a direct P2P connection between browsers without the need for third-party plugins.

Main setup steps:

1. Signaling: A signaling server (for example, on WebSocket) is needed for exchanging metadata (SDP, ICE candidates) between participants. It does not transmit media but only helps establish the connection.

2. Access to camera and microphone: Access to audio and video is requested via navigator.mediaDevices.getUserMedia.

3. Creating RTCPeerConnection: Objects are created to manage the connection.

4. Exchanging SDP and ICE candidates: The signaling server facilitates the exchange of information to establish the connection.

5. Displaying video: Local and remote videos are displayed in <video> elements.

An example of simplified code to get video and audio:

navigator.mediaDevices.getUserMedia({ video: true, audio: true })
  .then(stream => {
    const localVideo = document.getElementById('localVideo');
    localVideo.srcObject = stream;
  })
  .catch(error => console.error('Error accessing camera/microphone:', error));

For full setup, a signaling server and message exchange logic between clients need to be implemented. Ready-made solutions or libraries (e.g., SimplePeer, PeerJS) are often used.