In the world of computing, an organizational unit (OU) provides the ability to classify objects in directories, or names in a digital certificate hierarchy, typically used to differentiate between objects with the same name (Example: Felicity Doe in OU “Sales” and Felicity Doe in OU “Customer service”). This functionality can be used to parcel out authority to create and manage objects such as giving rights for user-creation to local technicians instead of having to manage all user accounts from a single central group.

The Domain Name System (DNS) is arguably one of the most important components of a computer network and internet infrastructure. DNS unavailability presents all sorts of problems related to finding resources on an internal network as well as external internet resources, acting like a phone book to translate familiar names such as www.google.co.uk to the IP address 8.8.8.8 and vice versa.