With Audio and Video Bridging (AVB), the Institute of Electrical and Electronics Engineers (IEEE) AVB task group introduced Real-Time capabilities to Ethernet based on IEEE 802 Standards. As AVB was conceived with a focus on home and professional audio and video transmissions, some mandatory aspects for the application in industrial control networks are not covered. Under the name of Time-Sensitive Networking (TSN), second generation AVB standards are being developed to address the requirements of industrial automation and control networks, and automotive in-vehicle networks. One of the mandatory requirements addressed by TSN is a redundancy feature to achieve fault tolerance. This paper compares two methods for implementing fault-tolerant networks with the stream registration mechanisms that are planned for TSN.

No abstract

No abstract

No abstract

In the last decade, Ethernet technology has paved its way from the use in office environments into the world of mission-critical networks, e.g. in industrial automation and control in production environments. Recent advancements in power utility automation place Ethernet at the communication infrastructure of electrical substations. To fulfill the requirement of drop-out free fault-tolerance in this application field, new Ethernet redundancy mechanisms have been developed: HSR and PRP. These methods are usually implemented in hardware, e.g. FPGAs. Thus, several key performance characteristics of the protocol are implementationspecific and can be altered. This paper gives an overview of PRP and HSR, outlines the implications of the protocol design in hardware to physical topologies and describes how design decisions can influence protocol performance.