A Sieve Method for Consensus-type Network Tomography

In this note, we examine the problem of identifying the interaction geometry among a known number of agents, adopting a consensus-type algorithm for their coordination. The proposed identification process is 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. It is first noted that under the assumption of controllability and observability of corresponding steered-and-observed network, the proposed procedure identifies a number of important features of the network using the spectrum of the graph Laplacian. We then proceed to use degree-based graph reconstruction methods to propose a sieve method for further characterization of the underlying network. An example demonstrates the application of the proposed method.