Use of T-310 Encryption During German Reunification 1990


  • Winfried Stephan



T-310, ALPHA_Algorithm, Chiffrator, Encryption Unit, Long-Term Key, Short-Term Key, Keyspace, Periodicity German Reunification, FRG, GDR, BSI, government bunkers


One of the well-kept political secrets in the few months between the peaceful revolution in the GDR and the reunification of the two German states was the use of GDR cryptological equipment to secure communications between the western FRG and the eastern GDR. The T-310 cipher device, which was approved for state secrets, was selected for secure transmission on teletype links. During this transitional period the interior ministries of the two German states had to coordinate their interaction. The use of the GDR's T-310 cipher machine for the secure message connection of the teletype networks between the two interior ministries was prepared and carried out by intelligence units of the two German states. The secured connections were operated by the cipher services, which worked in the top-secret facilities of the two government bunkers. As part of the politically necessary cooperation, the best-kept secrets of the GDR's state cryptology were handed over to the former “class enemy” along with information about the T-310 cipher algorithm.The following statements are largely based on interviews with people acting at the time. Some of this information is summarized and published here for the first time.