3. Reconciling historic and emerging models: a field-tested necessity

Over the last twenty years, IS architectures have evolved from so-called "historical" models, where information was hosted internally and the IS manager had the ability to control who could access it, and was solely responsible for its protection, to a more open, so-called "hybrid" model, where information is sometimes hosted internally and sometimes in a cloud, or even in several clouds. In this new model, the location of data becomes imprecise (when it is not completely unknown) and its protection is no longer the concern of a single player, but becomes a shared responsibility between the IS manager and cloud providers.

IS security models have evolved along with their architecture models, bringing new benefits rather than replacing existing ones. In this respect, the Zero Trust Network concept, which meets new security needs, does not eclipse the benefits of effective...