what if someday when bitcoin has become the main payment instruments in the world. and how when the Internet network paralyzed. it means that we all can not perform various financial transactions? , is there any solution ?
Use cash.
Indeed, if internet is totally dead everyone will find a other way like using a cash on their daily transaction. However, I think will never gonna happen because if it occur the bitcoin will die. We all know that the only way to use bitcoin is through internet connection.
Furthermore we were in the modern world they will never let that happen because it is the fastest way to communicate to others.