  Future communication networks are expected to feature autonomic (or
self-organizing) mechanisms to ease deployment (self-configuration), tune
parameters automatically (self-optimization) and repair the network
(self-healing). Self-organizing mechanisms have been designed as stand-alone
entities, even though multiple mechanisms will run in parallel in operational
networks. An efficient coordination mechanism will be the major enabler for
large scale deployment of self-organizing networks. We model self-organizing
mechanisms as control loops, and study the conditions for stability when
running control loops in parallel. Based on control theory and Lyapunov
stability, we propose a coordination mechanism to stabilize the system, which
can be implemented in a distributed fashion. The mechanism remains valid in the
presence of measurement noise via stochastic approximation. Instability and
coordination in the context of wireless networks are illustrated with two
examples and the influence of network geometry is investigated. We are
essentially concerned with linear systems, and the applicability of our results
for non-linear systems is discussed.
