Table 1.

The comparison of related work on the security assumptions.

Schemes	The Underlying Mathematical Assumptions
[15]	Computational Diffie-Hellman (CDH)
[19]	Discrete Logarithm (DL)
[20]	RSA
[6]	Quadratic Residues
IBMSCR-1	Cubic Residues
IBMSCR-2	Cubic Residues