Fieldbus-internet connectivity: the SNMP approach

Important reasons for connecting fieldbus systems to IP-based networks are the provision of remote access for monitoring and maintenance purposes, but also the inclusion of automation systems into an enterprise-wide management scope. Existing solutions are chiefly based on Web technology or require specialized, fieldbus-dependent tools. In this paper, the authors propose a different strategy using the standardized and widely used Simple Network Management Protocol. This approach is largely fieldbus-independent and, at the same time, interoperable with existing LAN technology. They discuss the architecture of a protocol conversion gateway and present a modular approach to cope with the variety of available fieldbus protocols. They further propose a structure for a management information base suitable to represent the fieldbus data objects. By means of prototype implementations for different fieldbus systems (Profibus, P-NET, and EIB), they study the influence of the underlying fieldbus communication principles on the gateway implementation and operation.