HIME(R) is the public-key cryptosystem and based on a modular squaring
(Rabin's public-key encryption scheme) over Z_N, where N=p^dq (p and q are
prime integers, and d>1), and utilizes the fast calculation method for
decryption. With HIME(R), security is additionally enhanced by the OAEP
converting method.

HIME(R) has the following exceptional features:

It is proven to be semantically secure against an adaptive
chosen-ciphertext attack(IND-CCA2) in the random oracle model under the
factoring assumption of N.

It has a very fast encryption speed.

The decryption speed (1536 bits) is about two-and-a-half times faster
than that of RSA-OAEP (1024 bits).

The plaintext space is sufficiently large.

The amount of computation for the encryption and decryption increases
only slightly compared with previous schemes, even if the size of N
increases in the future.