Summary: Distributed Computing manuscript No.
(will be inserted by the editor)
Dana Angluin · James Aspnes · Zoše Diamadi · Michael J. Fischer · RenŽe Peralta
Computation in Networks of Passively Mobile Finite-State Sensors
October 17, 2005
Abstract The computational power of networks of small
resource-limited mobile agents is explored. Two new models
of computation based on pairwise interactions of finite-state
agents in populations of finite but unbounded size are de-
fined. With a fairness condition on interactions, the concept
of stable computation of a function or predicate is defined.
Protocols are given that stably compute any predicate in the
class definable by formulas of Presburger arithmetic, which
includes Boolean combinations of threshold-k, majority, and
equivalence modulo m. All stably computable predicates are
shown to be in NL. Assuming uniform random sampling of
interacting pairs yields the model of conjugating automata.
Any counter machine with O(1) counters of capacity O(n)
can be simulated with high probability by a conjugating au-
tomaton in a population of size n. All predicates computable