Integrating IP traffic into fieldbus networks

Fieldbus networks are traditionally used in order to interconnect devices at the field level e.g. sensors and actuators, so that real time or critical time requirements are met concerning data transfer. In addition to traditional fieldbus traffic, novel applications, such as industrial multimedia applications, require the integration of IP traffic into fieldbus networks as well. This integration should be done so that the usual control traffic is not inhibited in any way by IP traffic, while on the other hand specific Quality of Service requirements are met by IP traffic. This paper deals with the different problems that are relevant to the integration of IP traffic into fieldbus networks. It focuses especially on the IP Mapper layer that need to be incorporated between the TCP/IP Stack and the Fieldbus Data Link Layer and performs the appropriate conversion of IP datagrams into fieldbus datagrams as well as the integration of the TCP/IP and the fieldbus communication models. Finally, it presents the way that these problems have been addressed for the integration of IP traffic over a specific fieldbus network.