Keep a register of all your assets
The objective is to have up-to-date knowledge of all IT devices in use. This understanding helps you identify possible attack vectors and essential assets for your organization. In case of an incident it can help you to detect where the problem comes from and potentially which supplier you need to contact.
To achieve this you should keep an inventory of your IT assets, like network devices, internet connected servers, workstations, mobile devices and end-user devices. This inventory of IT assets allows you to understand the scope of your essential assets, to check your maintenance contracts, to identify those resources that are no longer used, but have not yet been decommissioned and to focus budget on the assets that matter to your organization. For the identification of essential assets it can be useful to link this IT inventory to key business activities and processes. It’s important to keep this inventory up-to-date.