A Fiber-Optic-Based Protocol for Manufacturing System Networks: Part I—Conceptual Development and Architecture

The goal of Computer Integrated Manufacturing (CIM) is to put together the diverse areas of engineering, design and production processes, material inventory, sales and purchasing, and accounting and administration into a single interactive closed loop control system [1]. Essential to this distributed total manufacturing system is the integrated communications network over which the information leading to process interactions, and plant management and control will flow. Such a network must be capable of handling heterogeneous real-time (e.g., data packets for inter-machine communications at the factory floor) and non-real-time (e.g., Computer Aided Design (CAD) drawings, design specifications, and administrative information) traffic. This sequence of papers in two parts presents the development and analysis of a novel fiber-optic-based medium access control (MAC) protocol for integrated factory and office communications. Its adaptation as the common MAC layer protocol in the fiber-optic-based version of Manufacturing Automation Protocol (MAP) [2] and Technical and Office Protocols (TOP) [3], will make their specifications identical up to the presentation layer; only the application layer which is user-specific could be different. This first part provides the necessary background for the reported work and details of the protocol which is represented by a finite-state-machine model. Part II [4] presents the performance analysis of the protocol using a statistical model, and a comparison of the simulation and analytical results.