Supporting internet protocols in master-slave fieldbus networks'

In this paper we describe how to integrate Internet protocols (TCP/IP) into a typical hierarchical master-slave fieldbus network, supporting a logical ring token passing mechanism between master stations. The integration of TCP/IP in the fieldbus protocol rises a number of issues that must be addressed properly. In this paper we particularly address the issues related to the conveyance of IP Datagrams in fieldbus frames (fragmentation/de-fragmentation) and on how to support the symmetry inherent to the TCP/IP protocols in fieldbus slaves, which lack communication initiative. Copyright (C) 2001 IFAC.