Remote monitoring infrastructure for IEC 61499 based control software

In this paper, we present our work on monitoring of control software behavior for PLCs. In particular, we are looking at IEC 61499-based software specifications. Monitoring is done remotely, i.e., the interface behavior of function blocks is streamed to a cloud-based service. Specifications are realized using formal languages such as 1) regular expressions, 2) timed automata, 3) temporal logic. Monitors can be automatically generated from these languages. Using our specifications, we are able to detect abnormal behavior in control software such as timing changes that can, e.g., show the presence of memory leaks or a virus. We demonstrate our ideas using an example.