The Grenztruppen used a password system to identify other patrol members while conducting their security duties. The system was similar to the procedure used by US Army units with minor variations. Unlike the US system, the person being challenged was required to say the first word of the challenge. The password had to consist of two nouns that started with the same letter such as the words "Rostock" and Ruegen". Below is an example of how the password was exchanged:

 Guard: "Halt! Border post - Password!"

Other person: "Rostock!"

Guard:  "Ruegen - You may pass."

The password was in effect for 24 hours.