Paper Info
Title
Efficient Identity-Based Encryption With Hierarchical Key-Insulation From Hibe
Abstract
Hierarchical key-insulated identity-based encryption (HKIBE) is identity-based encryption (IBE) that allows users to update their secret keys to achieve (hierarchical) key-exposure resilience, which is an important notion in practice. However, existing HKIBE constructions have limitations in efficiency: sizes of ciphertexts and secret keys depend on the hierarchical depth. In this paper, we first triumph over the barrier by proposing simple but effective design methodologies to construct efficient HKIBE schemes. First, we show a generic construction from any hierarchical IBE (HIBE) scheme that satisfies a special requirement, called MSK evaluatability introduced by Emura et al. (Des. Codes Cryptography 89(7):1535-1574, 2021). It provides several new and efficient instantiations since most pairing-based HIBE schemes satisfy the requirement. It is worth noting that it preserves all parameters' sizes of the underlying HIBE scheme, and hence we obtain several efficient HKIBE schemes under the k-linear assumption in the standard model. Since MSK evaluatability is dedicated to pairing-based HIBE schemes, the first construction restricts pairing-based instantiations. To realize efficient instantiation from various assumptions, we next propose a generic construction of an HKIBE scheme from any plain HIBE scheme. It is based on Hanaoka et al.'s HKIBE scheme (Asiacrypt 2005), and does not need any special properties. Therefore, we obtain new efficient instantiations from various assumptions other than pairing-oriented ones. Though the sizes of secret keys and ciphertexts are larger than those of the first construction, it is more efficient than Hanaoka et al.'s scheme in the sense of the sizes of master public/secret keys.
Year
DOI
Venue
2021
10.1007/s10623-021-00926-z
DESIGNS CODES AND CRYPTOGRAPHY
Keywords
DocType
Volume
Hierarchical identity-based encryption, Hierarchical key-insulated identity-based encryption, Generic constructions
Journal
89
Issue
ISSN
Citations 
10
0925-1022
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
Keita Emura131636.97
Atsushi Takayasu2368.90
Yohei Watanabe3136.64