For instance, shift operation unit, S-box substation unit, modular (2~n+1) add unit, modular (2~n+1) multiplication and bit permutation unit. This paper has realized extending ISA for dealing with symmetric-key cryptography.

• 基于FPGA方式研究了移位运算、S盒实现、模(2~n+1)加、模(2~n+1)乘、比特置换等运算的硬件实现原理，实现了扩展对称密码处理指令。