best design for an responsibility system

Question

I am trying to build a main system ( web application ) that contain different systems

that provide service for sales , packing and HR dept etc , so i have many users (about one thousand users ) with different page access permissions ( dynamic responsibility that may change at any time )

what is the best design for the responsibility system that can give them the permission to access for some page that developed for them

thx in advance

i have tried to give each system ,page and user an id ,

the store in DB for each user the system and page ids that can be accessed by this user