What is DOD communications architecture ?

A networking model developed by the U.S. Department of Defense (DoD).

The DoD model was developed in the1970s as the networking model for the Transmission Control Protocol/Internet Protocol (TCP/IP), which was first deployed by in the ARPANET project and is now the worldwide de facto standard for the Internet. The DoD model is older than the seven-layer Open Systems Interconnection (OSI) model, which was developed in the1980s by the International Organization for Standardization (ISO) to provide a more detailed framework for developing network protocols.

The DoD model consists of four layers. These layers map loosely to the seven-layer OSI model in the fashion described below. Describing the DoD layers from the top down, they are