Is it permissible to know the identity of visitors to avoid meeting certain people?

It is permissible for you to know who will visit you at your home and to prevent them from visiting if you do not desire their visit. It is also permissible for you to turn them away when they arrive at your home, based on the Almighty's saying: "O you who have believed, do not enter houses other than your own houses until you ascertain welcome and greet their people. That is better for you that you may be reminded. And if you find no one therein, then do not enter them until permission has been given you. And if it is said to you, 'Go back,' then go back; it is purer for you. And Allah is Knowing of what you do."