  Network virtualization and programmability allow operators to deploy a wide
range of services over a common physical infrastructure and elastically
allocate cloud and network resources according to changing requirements. While
the elastic reconfiguration of virtual resources enables dynamically scaling
capacity in order to support service demands with minimal operational cost,
reconfiguration operations make resources unavailable during a given time
period and may incur additional cost. In this paper, we address the dynamic
cloud network control problem under non-negligible reconfiguration delay and
cost. We show that while the capacity region remains unchanged regardless of
the reconfiguration delay/cost values, a reconfiguration-agnostic policy may
fail to guarantee throughput-optimality and minimum cost under nonzero
reconfiguration delay/cost. We then present an adaptive dynamic cloud network
control policy that allows network nodes to make local flow scheduling and
resource allocation decisions while controlling the frequency of
reconfiguration in order to support any input rate in the capacity region and
achieve arbitrarily close to minimum cost for any finite reconfiguration
delay/cost values.
