A. N. Pavlov

One of the main features of modern disaster tolerance information systems (DTIS) is that their parameters and structures at various stages of life cycle continuously change for various reasons. Under structural reconfiguration of DTIS we will understand process of DTIS structure change with a view to keeping, restoration (increase) of working ability level of DTIS, or providing of the minimum decrease in DTIS application efficiency level at degradation of her functions. On the one hand, DTIS, as a rule, represents nonmonotonic system. On the other hand, process of DTIS structure reconfiguring is directly connected with a set of possible variations of the structure representing operations with elements and links of structural model. Application of the specified operations of structural reconfiguration should not have mechanical nature that can lead to paralogism of functioning the processes and systems being described as a whole. The universal graphic tool offered by professor Mozhaev A.S. which he has named as the scheme of functional integrity, and also graphical-analytical method for solving the logic equations allows constructing the logical-probabilistic model (both with independent and incompatible events) of DTIS functioning considering the specified features. On the basis of logical-probabilistic model the monotonic or nonmonotonic system structure genome, representing vector which components are coefficients of a polynomial function of the minimum sections of refusals of the structure made of homogeneous elements. The problem of structural reconfiguration of DTIS is presented as an optimization problem of construction of structure degradation scenarios, at which changing over DTIS from the initial structural condition into required structural condition is accompanied by staying the system in the most reliable conditions. The basis of a formal statement of the problem is the concept of structure genome. A structure genome holds in storage topological properties of structure and allows determining the pessimistic, optimistic and average integrated evaluations of system reliability globally and partial the elements faults criticality connected with her structural generation. Features of the considered problem of structural reconfiguration of DTIS have been analyzed, and application of the search optimization methods for its solution has been proved.