The cascade vulnerability problem

Efficient heuristic algorithms for correcting the Cascade Vulnerability Problem for interconnected networks

“…As in [15,13,3,4], we assume that data security levels are totally ordered. Hence, the users cleared at a security level can read all data labeled with the same or a lower security level.…”

“…The notion of information flow graph is very useful in the study of Cascade Vulnerability Detection and Correction (e.g., [15,14]). In the following, we always use the terms node and link to refer to elements of the interconnection network and the term vertex and arc to refer to the elements of the information flow graph.…”

“…These schemes include: (a) The Nesting and Cascade Condition, (b) a Heuristic Procedure, (c) a Shortest Path Formulation approach, (d) the Horton et al algorithm [15], and (e) the Soft Constraints approach.…”

“…A problem with this algorithm, common to the algorithm by Horton et al [15], is that if there are multiple cascade paths between a pair of nodes, only one of the paths will be detected in the straightforward version of the algorithm. A possible solution would be to keep all known paths between any two nodes.…”

“…An efficient algorithm for the detection of cascade paths is presented in [15]. This algorithm uses the information flow graph to model the interconnection network of trusted computer systems, computes the shortest path from the vertex (u, h u ) to the vertex (v, s v ) for every pair of network nodes u, v 2 N, and checks whether this is a cascade path.…”