  Network functions (e.g., firewalls, load balancers, etc.) have been
traditionally provided through proprietary hardware appliances. Often, hardware
appliances need to be hardwired back to back to form a service chain providing
chained network functions. Hardware appliances cannot be provisioned on demand
since they are statically embedded in the network topology, making creation,
insertion, modification, upgrade, and removal of service chains complex, and
also slowing down service innovation. Hence, network operators are starting to
deploy Virtual Network Functions (VNFs), which are virtualized over commodity
hardware. VNFs can be deployed in Data Centers (DCs) or in Network Function
Virtualization (NFV) capable network elements (nodes) such as routers and
switches. NFV capable nodes and DCs together form a Network enabled Cloud (NeC)
that helps to facilitate the dynamic service chaining required to support
evolving network traffic and its service demands. In this study, we focus on
the VNF service chain placement and traffic routing problem, and build a model
for placing a VNF service chain while minimizing network resource consumption.
Our results indicate that a NeC having a DC and NFV capable nodes can
significantly reduce network-resource consumption.
