Each multicast group is identified by so-called @strong{area}. Area
consists of private/public Curve25519 keypairs for @ref{Encrypted area,
packets encryption}, identity (BLAKE2b-256 hash of the public key) and
-possible subscribers.
+possible subscribers. Areas are created with @ref{nncp-cfgnew} command.
You can make either file or exec transmissions to the areas. Those
ordinary file/exec packets are double wrapped in:
relay it to the @code{nodeA} also, that will silently remove it when
tossing, because it was already seen.
-@strong{TODO}: we must not relay packet to the node also presenting as
-the sender of the area's message. Obviously it has seen it.
-
@item
When @code{nodeC} sends message to the area, then @code{nodeA} will
receive it twice from @code{nodeB} and @code{nodeD}, ignoring one of