2SC: An Efficient Code-Based Stream Cipher

  • Mohammed Meziani
  • Pierre-Louis Cayrel
  • Sidi Mohamed El Yousfi Alaoui
Part of the Communications in Computer and Information Science book series (CCIS, volume 200)


In this article, we present a new code-based stream cipher called 2SC, based on the sponge construction. The security of the keystream generation of 2SC is reducible to the conjectured intractability of the Syndrome Decoding (SD) problem, which is believed to be hard in the average case. Our stream cipher compares favorably with other provably secure stream ciphers such as QUAD and SYND in terms of efficiency and storage. In particular, 2SC is much faster than both these stream ciphers, requiring shorter keys and initial vectors (IVs) in order to attain comparable security levels (the runtime in terms of clock cycles is actually halved compared to SYND for around 170 bits of security, whereas the key size is about 50 bits smaller).


Stream ciphers Provable security Syndrome decoding 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Mohammed Meziani
    • 1
  • Pierre-Louis Cayrel
    • 1
  • Sidi Mohamed El Yousfi Alaoui
    • 1
  1. 1.CASED – Center for Advanced Security Research DarmstadtDarmstadtGermany

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