Experimental Validation of a RDMA-based High Availability Concept over a deterministic IP-based network

Abstract

The edge computing paradigm continues to disrupt areas such as the automation domain where hardware-based implementations, i.e., programmable logic controllers (PLCs), have dominated for decades. The shift to virtualization and data center technologies offers both new opportunities and risks. By providing the first experimental validation of Remote Direct Memory Access (RDMA) over a deterministic IP-based network, we converge the IT and OT domains with a high availability approach for virtualized PLCs. Synchronizing the state of two PLC instances via RDMA provides fault tolerance across multiple data centers and exemplifies the potential of data center technologies for the automation industry. The experimental validation demonstrates the excellent match between the communication requirements of RDMA and the characteristics of the deterministic network. Finally, the need for deterministic acyclic communication in the pursuit of IT/OT convergence is illustrated.