On the Relations Between Non-Interactive Key Distribution, Identity-Based Encryption and Trapdoor Discrete Log Groups.
Kenneth G. Paterson, Sriramkrishnan Srinivasan · IACR Cryptology ePrint Archive · 2007
This paper investigates the relationships between identity-based non-interactive key distribution (ID-NIKD) and identity-based encryption (IBE). It provides a new security model for ID-NIKD, and a generic construction that converts a secure ID-NIKD scheme into a secure IBE scheme. This conversion is used to explain the relationship between the ID-NIKD scheme of Sakai, Ohgishi and Kasahara and the IBE scheme of Boneh and Franklin. The paper then explores the construction of ID-NIKD and IBE schemes from general trapdoor discrete log groups. Two different concrete instantiations for such groups provide new, provably secure ID-NIKD and IBE schemes. These schemes are suited to applications in which the Trusted Authority is computationally well-resourced, but clients performing encryption/decryption are highly constrained.