ow, sorry for multiple comment,
after searching in internet, i got a little bit idea where and how to start,
yes, that's what I'm thinking too, your also right that what you've done before is different to what i want, because i would like to pass only those who are in the list, so that no intruder could open it.
The only thing I'm thinking is where to buy the ID-12 Innovation RFIF Card Reader and a RFID Tag, i found sites but i don't know if they can send my orders in my country,
i may get back here to ask another related question if i already purchased those things i needed.
by the way, thanks for your reply,