Consensus is a fundamental problem for the development of reliable distributed systems deployed over dynamic networks, such as P2P, desktop grids, mobile ad-hoc networks, etc. Unlike classical networks, where the set of participants and their identities are known, in dynamic networks, the membership of the system and its cardinality are not known a priori. Recently, necessary and sufficient conditions have been identified to solve consensus in these environments, but for the message passing communication model. In this paper, we extend these recent results and present protocols able to solve consensus with unknown participants in the shared memory model.