Calculation of Unpredictable Time Deviation from Defined Enterprise Information System Recovery Effort in Emergency Situations

The present paper deals with creation of a model which estimates the negative impact of an unexpected factor on an enterprise information system recovery process, which is planned by the Business Continuity Management teams, towards a system outage caused by another foreseen crisis event. The core hypothesis of the contribution is the simultaneous occurrence of an unexpected factor during the information system restoration procedure, after a failover triggered by a crisis situation, for which the action steps are delineated in the Business Continuity Plan. In such case, the unexpected factor can negatively influence the estimated Recovery Time Effort (RTE) of the corresponding IT Business Process. Important part of the current work is the calculation of the approximate time deviation from the initially planned recovery time of the business function. The developed model is based on the Composite Risk Index theory of Risk Management.