On Sun, 28 Jun 2020 23:39:49 -0600, Grant Taylor
 declaimed the following:


>Yep.  This is some of what UUCP does.

 Except, from your examples, the source is still requesting a route to
the final destination -- which the OP seems insistent is not viable for
him. He wants both sides to only address the R-Pi in the middle, and they
must each initiate the connection /to/ the R-Pi.

 Which, even with UUCP, comes down to the source connecting/passing the
data to the R-Pi only, and the destination also using UUCP for
connecting/fetching the data from the R-Pi. So... again we have the R-Pi as
a file drop/mail box and UUCP/NFS/(s)FTP are essentially equivalent in
functionality. Files are transferred into some storage on the R-Pi -- there
is no real time packet transfer from one machine to the other (and
especially no ad-hoc protocols).

 What the OP wants is almost the reverse of a VPN where both sides are
treated as part of the same local/private network, with connections
tunneled through the unsecured public network to a VPN server.


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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