The mmmv_symsig_t1 wraps symmetric key encryption command line tools and implements a signing system, where parties, who have never met directly for a key exchange can probabilistically authenticate each other. 

It's worth to note here that if both of the keys of a public encryption algorithm are bundled together and the bundle is treated the same way as symmetric key encryption keys are treated, then public key encryption algorithms can be used as symmetric key encryption algorithms. That allows the "standard" tools like the GNU Privacy Guard to be used in the role of the symmetric key encryption algorithm implementation.

Overview