1. A covert channel involving the direct or indirect writing to a storage location by one process and the direct or indirect reading of the storage location by another process. Covert storage channels typically involve a finite resource (e. G. , sectors on a disk) that is shared by two subjects at different security levels. 2. A covert channel that involves the direct or indirect writing of a storage location by one process and the direct or indirect reading of the storage location by another process. Covert storage channels typically involve a finite resource (e. G. , sectors on a disk) that is shared by two subjects at different security levels.