Medusa: the design and development of a TCP/IP communications nexus for the MOOS Portable Ocean Observatory Program

One of the key capabilities envisioned of MOOS (MBARI Ocean Observing System) is to provide both power and communications to oceanographic instrumentation in the benthic environment. With many technical elements, such as low-power instrument control 'nodes' and EOM (electro optical mechanical) cabling being proven at sea, the need to manage TCP/IP communications over a fiber optic link to the benthic environment became apparent. This requirement led to the construction of a custom network switch with fiber optic capability named Medusa. Medusa provides the foundation for MOOS undersea networks with managed L2 TCP/IP packet switching including fault tolerance and enhanced diagnostic capabilities for gauging the health of the undersea network. This paper describes the overall requirements, design, software capabilities, and features of the Medusa platform