Hello, I extend my LAN connection using powerline cable and I bought DHP-P309AV starter kit with pass-through socket. I plug the device in my working room and my bedroom. They both work normally but I want to know is it secure or not? How do I know that my connection secure or not? On side of the device have a button and I press it both device but nothing happen, it is just blinking shortly and back to normal. Thank you.