Network Identification via Node Knockout

This technical note examines the problem of identifying the interaction geometry among a known number of agents, adopting a (weighted) consensus-type algorithm for their coordination. Inspired by how biologists use gene knockouts for experimentally identifying genetic interaction networks in cellular organisms, we propose a node-knockout procedure for the complete characterization of the interaction geometry in consensus-type networks. In our context, the node knockout is essentially a grounding procedure- where the node broadcasts a zero state to its neighbors without being removed from the network. The proposed centralized identification process is also facilitated by introducing “ports” for stimulating a subset of network vertices via an appropriately defined interface and observing the network's response at another set of vertices. We then provide an example for the utility of such a network identification process in the context of fault detection for networked systems.