RTCPeerConnection

uses
  sgcP2P;

var
  Peer: TsgcRTCPeerConnection;
  Channel: TsgcRTCDataChannel;
begin
  Peer := TsgcRTCPeerConnection.Create(nil);
  Peer.IceServers.Add('stun:stun.l.google.com:19302');

  Peer.OnLocalDescription := procedure(Sender: TObject;
    const aSDP: string)
  begin
    SignalToPeer(aSDP); // over your WebSocket / WebRTC signalling
  end;

  Peer.OnDataChannel := procedure(Sender: TObject;
    aChannel: TsgcRTCDataChannel)
  begin
    Channel := aChannel;
    aChannel.OnMessage := procedure(Sender: TObject;
      const aText: string)
    begin
      Memo1.Lines.Add(aText);
    end;
  end;

  // outbound side
  Channel := Peer.CreateDataChannel('chat');
  Peer.CreateOffer;
end;