Supporting Timing-Channel Free Computations in Multilevel Secure Object-Oriented Databases
Ravi S. Sandhu, Roshan K. Thomas, Sushil Jajodia · 1991
In an earlier paper #3#, Jajodia and Kogan proposed a message #lter approach to enforcing mandatory securityinmultilevel object-oriented databases. The key idea in the message #lter model is that all information exchange be permitted solely through messages and that security be enforced by a message #lter component that mediates these messages. In a recent paper #8# the authors proposed a kernelized architecture for implementing the message #lter model. A major complication in implementing this model arises due to timing channels intrinsic to the object-oriented model of computing. These channels arise because object-oriented #write-up" operations are abstract and arbitrarily complex #as opposed to primitive memory writes#. One approach to closing these timing channels is to execute a logically sequential computation as concurrent pieces. Our earlier paper presented an execution model for managing such concurrent computations as well asamultiversion synchronization protocol to guarante...