For some computer to find another in a network, there is a routing mechanism which describes how information is transferred between network nodes. The route is understood as sequence of network nodes through which it is possible to transmit information from source node to destination node. One of perspective methods of a computer network reliability increase is ensuring fast restoration of routes after failure of the network device. When the data can not be transferred on the main route due to its damage the source node switches to the backup route. In this case, it does not take time on the calculation of a new route. In this paper we propose proactive backup scheme of routes for dynamic changes in the structure and configuration of the network, which allows to reduce the recalculation time of optimal routes, thus increasing the efficiency of the routing mechanism.