Powerful Naval Data Multiplex Systems: A Look into FODMS and GEDMS

Evolving Naval Data Multiplex Systems

The Rockwell International Autonetics Marine and Aircraft System Division (AM&ASD), now under Boeing, initiated the development of general-purpose digital data bus systems for naval applications in 1970. Among the pioneering systems is the Data Multiplex System (DMS) AN/USQ-82(V), which served as a catalyst for modern naval communication.

DMS: Pioneering Naval Data Communication (1970s)

DMS was a groundbreaking linear, coaxial, five-way redundant digital data bus engineered to accommodate various standard US Navy signal types, ranging from discrete and analog to digital protocols. Its primary objective was to seamlessly integrate data bus technology into Navy vessels while minimizing the need for equipment modifications.

DMS achieved this by offering a wide array of options for user device interfaces. Its terminals and interface modules could be configured to match various interface signal specifications and digital device protocols. Moreover, DMS incorporated features to enhance survivability, ensuring it could support critical shipboard systems. Built to military specifications, it passed rigorous tests for shock, vibration, humidity, electromagnetic compatibility, and more.

In 1984, DMS successfully completed its US Navy Operational Evaluation (OPEVAL) and found its way into the design of Ashleigh Burke (DDG 51) class destroyers and the Wasp (LHD 1) class amphibious assault ships. DDG 51 class destroyers, in particular, now rely on DMS for machinery control, damage control, navigation, steering, and communication within the AEGIS combat system.

FODMS: Transition to Fiber Optic (1988)

As technology advanced, the US Navy explored commercial data bus standards in the 1980s. This led to the inception of the Fiber Optic Data Multiplex System (FODMS) in 1988. FODMS aimed to meet the requirements of the Survivable Adaptable Fiber Optic Embedded Network (SAFENET) while ensuring compatibility with existing DMS applications.

FODMS is based on the American National Standards Institute (ANSI) X3T9.5 Fiber Distributed Data Interface (FDDI) token ring architecture. It operates as a transparent data bus, offering compatibility with current DMS applications. FODMS utilizes two redundant packet-switched FDDI networks, meeting SAFENET standards for durability and survivability.

Presently, FODMS serves on DDG 51 Flight IIA Class Destroyer ships, supporting functions such as navigation data distribution, machinery control, and interior communication. Its adoption has reduced costs, increased performance, and simplified shipboard installations.

GEDMS: Gigabit Ethernet Takes Over (Present and Future)

The Gigabit Ethernet Data Multiplex System (GEDMS) represents the latest evolution in naval data communication. Currently being installed on the Ashleigh Burke DDG51 Flight II Class of destroyer ships (DDG 79 – 110), GEDMS replaces the FDDI backbone of FODMS with a Gigabit Ethernet backbone, significantly boosting overall networking bandwidth.

GEDMS employs a Mesh Topology over two independent network backbones for enhanced survivability. Each backbone utilizes Backbone Switch Enclosures (BSEs) to connect network and user links via fiber optic cables. The mesh topology backbone and user links facilitate data transfer between various user source and user sink devices.

In summary, the evolution of naval Data Multiplex Systems, from the inception of DMS in the ’70s to the present-day GEDMS, underscores the ongoing commitment to enhancing naval communication, survivability, and operational efficiency. These systems play a pivotal role in ensuring seamless data transfer across critical shipboard systems, contributing to the effectiveness of naval operations.


Data Multiplex Systems