Establishing a key hierarchy for Conditional Access without encryption

  • J. Schwenk
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT)


Conditional Access systems use special key management schemes which ensure that encrypted broadcast services can only be accessed by those who are entitled to receive them. In many cases, a key hierarchy is used for this purpose. In this article, solutions are presented to improve existing Conditional Access systems by using deeper key hierarchies, and by establishing these hierarchies without the use of encryption techniques.


Conditional Access cryptographic key management encryption Pay-TV polynomials threshold schemes tree structure 


  1. EBU (1995) Technical Review No. 266 (Winter 1995/96).Google Scholar
  2. Fiat, A. and Naor, M. (1994) Broadcast Encryption. Advances in Cryptology–CRYPTO 93 Proceedings. Springer-Verlag, Berlin, 480–491.CrossRefGoogle Scholar
  3. McCormac, J. (1994) European Scrambling Systems (4th edition). Waterford University Press.Google Scholar
  4. Schwenk, J. (1994) Security of Pay-TV Systems. In: Deutsche Telekom 1994 Research Review, pp. 9–21.Google Scholar
  5. DIN EN 50 094, Zugriffskontrollsysteme für die MAC/Packet-Familie: Eurocrypt. Beuth Verlag, Burggrafenstr. 6, 1000 Berlin 30.Google Scholar
  6. DE 33 25 858 Al, Mehrebenen-Verschlüsselungssystem zum Senden verschlüsselter Informationen (cf. US 401258).Google Scholar

Copyright information

© IFIP International Federation for Information Processing 1996

Authors and Affiliations

  • J. Schwenk
    • 1
  1. 1.Technologiezentrum Am Kavalleriesand 3Deutsche Telekom AGDarmstadtGermany

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