Wireshark dissector for Socket.IO traffic
Windows: append this to C:\Program Files\Wireshark\init.lua
dofile("C:\\Users\\kevin\\Documents\\wireshark-socket.io\\socketio_proto.lua")
OSX: Put socketio_proto.lua in ~/.wireshark/plugins/
Select a Socket.IO packet. Extra information is displayed.
Optional: enter websocket in the Wireshark filter (and press enter).
Optional: customize the column display by adding Custom columns SocketIO.msgno and/or SocketIO.reply_duration.