Consider a sub-population of rebels that wish to initiate a revolution. In order to avoid initializing a failed revolution, rebels would first strive to estimate their relative "power", which is often correlated with their fraction in the population. However, and especially in non-democratic countries, rebels refrain from disclosing themselves. This poses a significant challenge for rebels: estimating their fraction in the population while minimizing the risk of being identified as rebels. This paper introduces a distributed computing framework aiming to study this question. Our main takeaway message is that the communication pattern has a crucial role in achieving such a task. Specifically, we show that relying on the inherent noise in the communication, public communication, characterized by the fact that each message announced by an individual can be viewed by all its neighbors, allows rebels to estimate their fraction in the population while keeping a negligible risk of each rebel being identified as such. The suggested estimation protocol, inspired by historical events, is extremely simple and can be executed covertly even under extreme conditions of surveillance.Conversely, we show that under peer-to-peer communication, protocols of similar simplicity are either inefficient or non-covert.
INTRODUCTIONLarge scale changeovers in a population, such as political overthrows of dictatorships by rebels, are often perceived as complex emergent phenomena [9,18,19,34]. In order to avoid conducting a failed rebellion, rebels would typically refrain from initiating a revolution until they manage to obtain a reliable indication that many others will join them [6,30]. In other words, rebels would first try to understand whether "we are the many and they are the few" [33].However, and especially under non-democratic regimes, obtaining such information may not be a trivial task, as rebels often refrain from disclosing themselves as such. In turn, with the lack of such information, the status quo may continue to hold even when the support for a revolution is effectively high. Nevertheless, in some cases, rebels successfully coordinate their actions even under severe conditions of surveillance.Drawing on distributed computing reasoning, we argue that the pattern of communication can play a key role in the ability of rebels to reach such a coordination safely. We distinguish between two extreme patterns in a network environment:• Private communication: Each message sent by an agent is heard by a single neighbor.• Public communication: Each message sent by an agent is heard by all its neighbors. Private communication aims to capture one-to-one interactions, which are executed either directly in person or via a digital private messaging platform. In contrast, public communication aims to model social media infrastructures, such as Facebook or Twitter, that played a significant role during the Arab spring revolutions [19], behavioral communication, such as the "slow-motion" day organized by the opponents of the Pinochet dictator...