• Permissions are assigned to each and every data,
• each data has an owner, group and others permissions
• Permissions are divided into
  • s … see, data will be displayed in the User Interface
  • r … read, data could be read
  • w … write, data could be modified
  • x … extended, specifies handling of data assigned to the current data element

Since the data is organized in a hierarchical tree structure (with simple parent-child relations), a user can see a specific data item only if she has the permissions to see all parent data nodes down to the root of the tree too.

BIM-and users could be assigned to groups and will therefore have access to data that referes to these groups. The user-group assignment is furthermore specified with a set of srwx permissions.