My guess is that the "UK Government Digital Service", who run most central government it services, use govuk.digital as a top level domain for all internal serv

My guess is that the "UK Government Digital Service", who run most central government it services, use govuk.digital as a top level domain for all internal services. I believe it's fairly common to have a TLD that is only used for internal addresses, it helps to ensure they are only routed internally and not accidentally exposed. Using a "real" TLD also ensures you own the namespace and it can't be accidentally used by a third party. If they were to use an *.gov.uk domain for internal services there is a higher chance that someone would inadvertently expose it to the internet. https://www.gov.uk/government/organisations/government-digital-service https://www.gov.uk/government/organisations/government-digit...