This is ser2net, a program for allowing network connections to serial
ports.  See the man page for information about using the program.

Note that ser2net supports RFC 2217 (remote control of serial port
parameters), but you must have a compliant client.  The only one I
know of is kermit (http://www.columbia.edu/kermit).

If you want the opposite of ser2net (you want to connect to a "local"
serial port device that is really remote) then Cyclades has provided
a tool for this at http://www.coker.com.au/cyclades.  It is capable
of connecting to ser2net using RFC2217.

If you check this out from git, you won't have all the configure
programs and files, because those are generated.  Do:
   autoreconf -i
to generate everything first.  Then you can run configure.