Multi-recipient Public-Key Encryption with Shortened Ciphertext

  • Kaoru Kurosawa
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2274)


In the trivial n-recipient public-key encryption scheme, a ciphertext is a concatenation of independently encrypted messages for n recipients. In this paper, we say that an n-recipient scheme has a “shortened ciphertext” property if the length of the ciphertext is almost a half (or less) of the trivial scheme and the security is still almost the same as the underlying single-recipient scheme. We first present (multi-plaintext, multi-recipient) schemes with the “shortened ciphertext” property for ElGamal scheme and Cramer-Shoup scheme. We next show (single-plaintext, multi-recipient) hybrid encryption schemes with the “shortened ciphertext” property.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Kaoru Kurosawa
    • 1
  1. 1.Department of Computer and Information SciencesIbaraki UniversityIbarakiJapan

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