The Defense Message System and the U.S. Coast Guard

This thesis provides an overview of the Defense Message System (DMS) and the messaging related components of the Coast Guard Telecommunications System (CGTS) . Also addressed are the seven-layer Open Systems Interface (OSI) Reference Model, the Government Open System Interconnection Protocol, and various interface devices such as bridges, routers, and gateways. The DMS program is composed of a baseline architecture and three phases that will result in the transition from baseline systems and networks to a target architecture, with a goal for complete writer-to-reader messaging services. DMS baseline components, such as the Automatic Digital Network and components of the Defense Data Network, will either be phased out or transitioned into new architectures that will lead to the target architecture. The Coast Guard telecommunications organization is addressed as well as the broad aspects of the CGTS. A key issue of this thesis is to emphasize the importance of interoperability between the DMS and the CGTS through the use of approved standards and protocols.