Digital preservation is considered as a vital process in order to have long-term information; it has a short history and a fairly coherent and justified fundament. In this article, a comparison of models and standards of digital preservation is developed, as well as the current situation of digital preservation and an analysis about the most outstanding projects that can serve as a basis for the application of an existing preservation model in a specific setting, or the proposal of a new one. A comparison of the existing models and their application in the specific environment of institutions of criminal investigation is performed by determining its applicability to the relevant aspects required in this environment. It is important to bear in mind that for every application domain and its reality, there is a very high probability of requiring a particular model which can be based on the existing ones.