DP-Ethernet: the Profibus DP Protocol Implemented on Ethernet

The use of Ethernet networks at the low level of factory automation systems, which is even more frequent, requires the adoption of real time protocols to implement the typical functions of this level. This paper investigates the possibility of using of a very popular fieldbus protocol, Profibus DP, as a real time protocol for Ethernet. The proposal, named DP-Ethernet, makes use of the IEEE 802.2 Logical Link Control to implement the Profibus DP functions on Ethernet. The paper shows how DP-Ethernet could be implemented maintaining the compatibility with already existing Profibus DP applications. Moreover, some DP-Ethernet performance figures, obtained with a software simulation package, are given.