In many timesharing systems, the subsystems executed to perform a job are written by several different people. For example, the system I/O routines written by the system group are frequently invoked by other users. To provide security in this case, the operating system must provide confinement for subsystems in a job (senders) that might leak information through covert channels. One typical covert channel that is present in virtually all timesharing systems makes use of the CPU scheduling algorithm. The CPU scheduling covert channel to determine whether the amount of covert information leakage is significant, to explore the factors that influence the amount of leakage, and to determine the feasibility of partial confinement, which trades off leakage for computation cost is studied.
- Pub Date:
- Channels (Data Transmission);
- Computer Information Security;
- Time Sharing;
- Data Transmission;
- Systems Analysis;
- Communications and Radar