The availability of functioning IT systems is in many cases a prerequisite for government bodies to be able to maintain their daily operation. IT-dependence is therefore something that needs to be taken into account in all forms of contingency planning. If the government bodies' dependencies on IT systems and the IT systems' dependencies on external connections - most often to the Internet - are not mapped, this could lead to overestimation of operational capability during disruptions. In this report, we present a model for raising the level of knowledge about IT systems and their dependence on external connections. The overall aim of this report is to provide stakeholders with the knowledge to accurately identify and decide which processes that can be maintained in the absence of functioning external connections. Carrying out an analysis based on this model can help the reader identify which IT systems are used and the nature of dependencies on external connections. Such an analysis can, for example, form the basis for planning how organisations can scale down operations when cloud services cannot be accessed, to avoid large losses in productivity and to maintain communication with citizens when external connections malfunction.