Distributed anonymous computation of social distance

In a distributed social network, no single system holds information about all the individuals in the network, and no single system is trusted by all the individuals in the network. It is nonetheless desirable to reliably compute the social distance among individuals. This must be done anonymously, without giving away any identifying information about individuals in the social network, and reliably, without allowing anyone to pretend to be socially closer to someone else than they actually are. The Social Network Connectivity Algorithm, or SoNCA, accomplishes these goals in a distributed manner. This paper describes both the high-level algorithm and a concrete design that is intended for future use with a network, AllNet, designed to provide secure interpersonal communication utilizing all available means, including Internet, cellular communications, ad-hoc networking and delay-tolerant networking.