  We provide a protection system making use of encapsulation, messages
communication, interface functions coming from an object oriented model
described in previous works. Each user represents himself to the system by the
mean of his "USER" object type. The recognition procedure is suitable to every
one's needs. Any user's objects and types are labeled with a personal
signature, exclusively provided and known by the system. Administrator's rights
are restricted to backup procedures. The system verify each messages access, it
is robust because partitioned, flexible, suitable and psychologically
acceptable.
