Compulsory Border Protection Service
The Compulsory Border Protection Service (German: Grenzschutzdienstpflicht) was enacted by the German parliament in the Federal Border Protection Act of 18 August 1972, based on Article 12a of the German Constitution. The remaining provisions of the Federal Border Protection Act were repealed in 1994.
Source: Wikipedia — Compulsory Border Protection Service (CC BY-SA 4.0)