CCA-Secure Leakage-Resilient Identity-Based Key-Encapsulation from Simple (not q\mathtt{q}-type) Assumptions

In this paper, we propose a new leakage-resilient identity-based encryption (IBE) scheme that is secure against chosen-ciphertext attacks (CCA) in the bounded memory leakage model. It is the first CCA-secure leakage-resilient IBE scheme which does not depend on $\mathtt{q}$-type assumptions. More precisely, it is secure under the external k-Linear assumption. The leakage rate 1/10 is achieved under the XDLIN assumption