This function sorts out destinations registered in this machine from Level 0 to Level 5 in order of importance to set the upper limit of the access level (access allowed level) for each user.
For example, assume that Level 3 is set for a certain user as an access allowed level. In this case, that user can access destinations in Access Allowed Level 1 to 3, but cannot access destinations in Access Allowed Level 4 and 5.