1. A method of creating an IT-network representation including automatically discoverable active elements and passive elements, comprising: producing, by running a network auto-discovery tool, a logical discoverable-elements representation of the IT network which includes the automatically discoverable active elements and a discoverable-elements network topology; manually inserting, by a user by means of a network-element editor, representations of passive elements between automatically discovered elements into said discoverable-elements representation, thereby creating a combined logical representation which models the IT network with its automatically discoverable elements and passive elements.