  This paper studies regulated state synchronization of homogeneous networks of
non-introspective agents in presence of unknown nonuniform input delays. A
scale-free protocol is designed based on additional information exchange, which
does not need any knowledge of the directed network topology and the spectrum
of the associated Laplacian matrix. The proposed protocol is scalable and
achieves state synchronization for any arbitrary number of agents. Meanwhile,
an upper bound for the input delay tolerance is obtained, which explicitly
depends on the agent dynamics.
