From CUNY Academic Commons

Neptune (neptune.gc.cuny.edu) is a server running the PostgreSQL RDBMS.  Neptune can be accessed via SSH (secure shell) using port forwarding.  Port forwarding configures your local computer to forward all incoming TCP/IP requests on a particular port to a remote computer.  You are basically tricking the client application to think your local computer is a database server, when all it really is is a conduit to the real database server.