TheTgS-1 DUDEK (Polish:hoopoe) (Dalekopisowe Urządzenie Do Elektronicznego Kodowania --Teleprinter Device for Electronic Coding) was an on-line and off-line encryption system developed during theCold War in the 1960s in thePolish People's Republic by the Telkom Teletra company and the Ministry of Interior for use onteleprinter circuits. The units saw use in the PolishMinisterstwo Spraw Wewnętrznych networks serving the (Milicja Obywatelska), the (Służba Bezpieczeństwa), the Polish Ministry of National Defense (Ministerstwo Obrony Narodowej), the Ministry of Foreign Affairs (Ministerstwo Spraw Zagranicznych) and the National Bank of Poland (Narodowy Bank Polski). The Poles also pressedWarsaw Pact states to adopt the DUDEK sets for international traffic.
The DUDEK series used random symmetric keys provided on paper tapes, which wereXORed by the unit with the plaintext provided from the teleprinter or recorded on different paper tapes. The DUDEK sets were to be used in conjunction with teleprinters like the Siemens/Ceska Zbrojovka T-100 or the RFT T-51. The maximum transmission speed was at 50 or 75 Baud. The system was cleared up to thetop secret level by the Poles provided that it served within theTempested environment.
A newer and slightly improved model using theTTL technology instead of toroid cores logic was developed in the late 1970s and named theTgS-3 DUDEK.
The last DUDEK sets were retired by thePolicja as of January 1, 2011.
At least four basic versions are known to have existed:
Each version also had derivative models, which differed with regard to the type of punched paper readers and the associated ancillaries.
The T-352 and T-353 were theStasi adopted names of the TgS-1 and TgS-1M DUDEK sets respectively.
