I think if there is no export limitation about DES, DES is the best candidate
for MUST algorithm.
But in actual, DES is not exportable outside US and Canada.
On the other hand, DES can be implemented outside of US.
It would be possible to exchange encrypted messages by DES between US and
by using S/MIME compatible softwares in which DES are implemented in each
What should I think about such situation?
Mitsubishi Electoric Corp.
Info. Tech. R&D Center
Infomation Security Dept.