Real Time Data Collection and Control in a Distributed Simulator System Using Ethernet TCP/IP

The purpose of this paper is to present the “Stealth Protocol” which is a real time communication protocol residing above the TCP/IP layer. This protocol operates within a Local Area Network (LAN) in an ethernet communication environment. The McDonnell Douglas Helicopter Company (MDHC) simulation system consists of a distributed multi-processor VME chassis driving four simulators and several auxiliary stations. The system is controlled by one or more system control stations (SCS), acting as central control points which are themselves distributed. This protocol provides a mechanism for the central control points to maintain an “open window” into the memory space of the real time system over ethernet and can access and modify memory, transparent to the real time applications. The “Stealth Protocol” uses the socket connection techniques of the Ethernet-TCP/IP.