  Virtualization enables multiple applications to share the same wireless
sensor and actuator network (WSAN). However, in heterogeneous environments,
virtualized wireless sensor and actuator networks (VWSAN) raise new challenges,
such as the need for on-the-fly, dynamic, elastic, and scalable provisioning of
gateways. Network Functions Virtualization (NFV) is a paradigm emerging to help
tackle these new challenges. It leverages standard virtualization technology to
consolidate special-purpose network elements on commodity hardware. This
article presents NFV architecture for VWSAN gateways, in which software
instances of gateway modules are hosted in NFV infrastructure operated and
managed by a VWSAN gateway provider. We consider several VWSAN providers, each
with its own brand or combination of brands of sensors and actuators/robots.
These sensors and actuators can be accessed by a variety of applications, each
may have different interface and QoS (i.e., latency, throughput, etc.)
requirements. The NFV infrastructure allows dynamic, elastic, and scalable
deployment of gateway modules in this heterogeneous VWSAN environment.
Furthermore, the proposed architecture is flexible enough to easily allow new
sensors and actuators integration and new application domains accommodation. We
present a prototype that is built using the OpenStack platform. Besides, the
performance results are discussed
