Puzzle of the Day

In the last class, we discussed the Bell-LaPadula Model, and noted that subjects could read and write objects only if the subjects were in the same compartment as objects. This leads to a notion of confinement, and raises the issue of leaking information among compartments. Such leakage led one security expert to speculate that, as the need for secure computing continued to climb, people would gradually shift from multi-user computing systems to single-user computer systems, because then information could not leak among compartments (as there are no other processes on the system to leak information to).

1. How do single-user systems connected by a network (such as the Internet) differ from multi-user systems?
2. Do you agree or disagree with the expert?