The DNS server implementation must prevent the installation of organization-defined software and firmware components without verification that the component has been digitally signed using a certificate that is recognized and approved by the organization.

Software and firmware components prevented from installation unless signed with recognized and approved certificates include software and firmware version updates, patches, service packs, device drivers, and basic input/output system updates. Organizations can identify applicable software and firmware components by type, by specific items, or a combination of both. Digital signatures and organizational verification of such signatures is a method of code authentication.