• Journal of Korea Multimedia Society
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• v.14 no.6
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• pp.775-784
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• 2011

In this paper we introduce the notion of multi-receiver certificateless encryption that avoids the inherent key escrow problem of multi-receiver identity-based encryption, and also present a highly efficient multi-receiver certificateless encryption scheme which eliminates pairing computation to encrypt a message for multiple receivers, Moreover, the proposed scheme only needs one pairing computation to decrypt the ciphertext. Finally, we discuss how to properly transform our scheme into a new public key broadcast encryption scheme for stateless receivers based on the subset-cover framework, which enjoys the advantages of certificateless cryptography.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.1C
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• pp.14-21
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• 2011

Cryptographic protocols based on bilinear pairings provide excellent alternatives to conventional elliptic curve cryptosystems based on discrete logarithm problems. Through active research has been done toward fast computation of the bilinear pairings, it is still believed that the computational cost of one pairing computation is heavier than the cost of one ECC scalar multiplication. However, there have been many progresses in pairing computations over binary fields. In this paper, we compare the cost of BLS signature scheme with ECDSA with equvalent level of security parameters. Analysis shows that the cost of the pairing computation is quite comparable to the cost of ECC scalar multiplication for the case of binary fields.