I've been working with my PhD student, Domenico Amodeo, on understanding how infrastructure systems exhibit resilience. Briefly, when I first became involved in infrastructure resilience research, I was mostly focused on metrics and measurement of system level of service. This was in line with most researchers in infrastructure resilience. A conversation with Woody Epstein changed my mind considerably on this topic. Instead of focusing on metrics, we should focus on improvisation.
I'd been thinking along these lines already since I'd been reading a little bit in fault tolerant computing. I was wondering how infrastructure could exhibit similar flexibility if systems such as inland waterways and drinking water systems must be constructed as physical networks with considerable path dependency built in. Domenico began thinking about this with more insight from economics, management science, and the decision sciences, and he has begun formulating the ideas we describe in our invited commentary in IEAM (and other research under review) called protocol-driven resilience. Roughly, protocols are the informal and formal ways information flows through human networks in the infrastructure system. In normal operations, these networks have a given topology. However, in disrupted operations, these networks self-reorganize. This self-reorganization is largely what we believe provides the system with a resilient response.
We're just at the beginnings of understanding these patterns, but we look forward to sharing more with you about the protocol-driven resilience.