Virtual Infrastructure for collision-prone wireless networks

Abstract

Wireless ad hoc networks pose several significant challenges: devices are unreliable; deployments are unpredictable; and communication is erratic. One proposed solution is Virtual, Infrastructure, an abstraction in which unpredictable and unreliable devices are used to emulate reliable and predictable infrastructure. In this paper, we present a new protocol for emulating virtual infrastructure in collision-prone wireless networks. At the heart of our emulation is a convergent history agreement protocol that tolerates lost messages and crash failures. It is designed specifically for ad hoc deployments, for example, the set of participants is a priori unknown. The convergent history agreement protocol is quite efficient, as each agreement instance completes in a constant number of communication rounds, and the size of the messages is constant, independent of the length of the execution. Building on the convergent history agreement protocol, our virtual infrastructure emulation introduces only constant overhead per virtual round emulated. We believe that the techniques developed in this paper help to bring virtual infrastructure one step closer to a reality. Copyright 2008 ACM.