syntax = "proto2"; package webrtc.pb; message Message { enum Flag { // The sender will no longer send messages on the stream. FIN = 0; // The sender will no longer read messages on the stream. Incoming data is // being discarded on receipt. STOP_SENDING = 1; // The sender abruptly terminates the sending part of the stream. The // receiver can discard any data that it already received on that stream. RESET = 2; } optional Flag flag=1; optional bytes message = 2; }