IDEA derives much of its security by interleaving operations from different groups -- modular addition and multiplication , and bitwise eXclusive OR -LRB- XOR -RRB- -- which are algebraically `` incompatible '' in some sense .

IDEA derives much of its security by interleaving operations from different groups -- modular addition and multiplication , and bitwise eXclusive OR -LRB- XOR -RRB- -- which are chosen to be `` algebraically incompatible '' .
