Implementation of a secure gateway on Hughes Aircraft´s engineering design network

The implementation of a secure gateway on the Ethernet-based engineering design network (EDEN) at Hughes Aircraft Company is described. The philosophy and approach of the implementation are outlined along with some of the limitations of the design in terms of overall security. The implementation meets most of the primary objectives of the initial design. The design is simple and elegant and also is flexible enough to easily add functions to the gateway which was indeed the case in later enhancements to the gateway. Some limitations in security can be controlled by careful monitoring of all nodes on the network