There are many different levels on which we can examine security. Each one is different from others, all of them are dependent on the context. Hence the need to bear additional knowledge enabling efficient utilization of the knowledge by the computers. Such information can be provided by ontologies. The paper presents gathered requirements needed to be taken into account when creating an ontology. The method of ontology creation and the criteria for keywords selection are presented. Ontology created in such way should provide means for interoperability with other systems.