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.