This software is supposed to work as a "reference implementation" of the
suggested "whoson" internet protocol.  The protocol is expected to be
employed on "spam relay protected" mail servers to allow traveling
customers still send their email via the protected server.  For this, a
realtime database of "temporarily trusted" IP addresses is maintained by
a special daemon program.  The database may be filled by, e.g. POP/IMAP
servers, and used by SMTP server.  Another possible use of the protocol
is to have the database filled by RADIUS/TACACS server for all dialup
clients, and SMTP server using it to put the user identity into the
"Received" header along with the source IP address.  The protocol itself
is defined in a separate document "whoson.txt".

WWW: http://whoson.sourceforge.net