Influence of network parameters on the recovery time of a ring topology PROFINET network

:This paper proposes a study on the use of ring topology to increase availability of PROFINET networks. It discusses the influence of Media Redundancy Protocol (MRP), watchdog time, and the computational power of the PROFINET Controller on the communication recovery time after a ring fracture. The paper proposes to consider two main contributions to the overall recovery time: the first is related to the low level (Ethernet layer 2) redundancy management, while the second is related to the software configuration of the entire network. Several different configurations of networks have been created in laboratory and many others have been analyzed in real industry plants. The collected results show how watchdog could influence recovery time since its violation could trigger higher level routines whose duration is basically set by PROFINET controller computational capability. On balance, relevant suggestions to increase the availability of PROFINET networks are pointed out.