Currently the mmmv_mail_protocol_t1 lacks any code.

• Hide metadata as much as one can think of, including who writes to whom and the message receiving time and the messaging frequency.
• Symmetric key encryption, where each encryption key has a unique ID and no user specific data fields.
• Cryptotext modifications should be detectable.  Crypto software will probably include that feature. The mmmv_crypt_t1(TODO: add it to the Fossil repository) already has that feture.

Users U_1 ...U_n form a complete graph G_u. Graph G_uu is like G_u, except that each G_u unidirected edge is replaced with 2 directed edges, one directed edge in each direction. Each of the G_uu directed edges, E_g_uu_k, k inSet(1 to (n*(n-1)/2) ), represents a virtual mail moving channel.