This paper proposes a new broadcast encryption scheme for tiny IoT equipments (BESTIE), minimizing the private key size in each user. In the proposed scheme, the private key size is O(log n), the public key size is O(log n), the encryption time per subset is O(log n), the decryption time is O(log n), and the ciphertext text size is O(r), where n denotes the maximum number of users and r indicates the number of revoked users. The proposed scheme is the first subset difference based broadcast encryption scheme to reduce the private size O(log n) without sacrificing the other parameters. We prove that our proposed scheme is secure under q-Simplified Multi-Exponent Bilinear Diffie-Hellman (q-SMEBDH) in the standard model.
Category / Keywords: public-key cryptography / Broadcast encryption, public-key encryption, subset difference, short key Date: received 12 Nov 2019 Contact author: jiwonlee at hanyang ac kr, jihyek at kookmin ac kr, hoh at hanyang ac kr Available format(s): PDF | BibTeX Citation Version: 20191113:104012 (All versions of this report) Short URL: ia.cr/2019/1311