According to discussed with PTTGSP ( PTTPLC) customer , he have plan to upgrade PLC system (GSP5). For the point that I would to inform to you the exiting communication between GSP5 and GSP3 via " Profibus DP Fiber Optic". The further customer have been planning to upgrade GSP3 , that easier to cheer up Wifi product . I think this is the good time for you to present that with them for alternative solution.